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beruecksichtige naturwissenschaftliche Journale:
Journal of Agricultural and Food Chemistry - published by
The American Chemical Society -
Chemistry and biochemistry of agriculture and food along with safety, composition and processing; including feeds, pesticides, veterinary drugs, plant growth regulators, fertilizers, and other agro-chemicals with their metabolism, toxicology, and environmental fate and the chemical processes involved in nutrition, phytonutrients, flavors, and aromas.
Molecular Nutrition & Food Research - published by
Wiley-Interscience -
... is a primary research journal devoted to health, safety and all aspects of molecular nutrition such as nutritional biochemistry, nutrigenomics and metabolomics
European Food Research and Technology - published by
Springer -
The journal's mission is the fast publication of high quality papers on front-line research, new and novel techniques and developing trends in such disciplines as chemistry and biochemistry; technology and molecular biotechnology; nutritional chemistry and toxicology; analytical and sensory methodologies and food physics.
Chemical Senses - published by
Oxford Journals -
... publishes original research and review papers on all aspects of chemoreception in both humans and animals.
Annals of Nutrition and Metabolism - published by
Karger -
The editors of this journal show their dedication to this search by carefully selecting basic and clinical reports offering new information relating to human nutrition and metabolic diseases including their molecular genetics
Aktuelle wissenschaftliche Fachartikel der
genannten Journale:
Plant sterols and stanols are natural food ingredients found in plants. It was already shown in 1950 that they lower serum low-density lipoprotein cholesterol (LDL-C) concentrations. Meta-analysis has reported that a daily intake of 2.5 g plant sterols/stanols reduced serum LDL-C concentrations up to 10%. Despite many studies, the underlying mechanism remains to be elucidated. Therefore, the proposed mechanisms that have been presented over the past decades will be described and discussed in the context of the current knowledge. In the early days, it was suggested that plant sterols/stanols compete with intestinal cholesterol for incorporation into mixed micelles as well as into chylomicrons. Next, the focus shifted toward cellular processes. In particular, a role for sterol transporters localized in the membranes of enterocytes was suggested. All these processes ultimately lowered intestinal cholesterol absorption. More recently, the existence of a direct secretion of cholesterol from the circulation into the intestinal lumen was described. First results in animal studies suggested that plant sterols/stanols activate this pathway, which also explains the increased fecal neutral sterol content and as such could explain the cholesterol-lowering activity of plant sterols/stanols.
Peripheral blood mononuclear cells (PBMCs) generally refer to monocytes and lymphocytes, representing cells of the innate and adaptive immune systems. PBMCs are a promising target tissue in the field of nutrigenomics because they seem to reflect the effects of dietary modifications at the level of gene expression. In this review, we describe and discuss the scientific literature concerning the use of gene expression at the mRNA level measured from PBMCs in dietary interventions studies conducted in humans. A search of literature was undertaken using PubMed (last assessed November 24, 2011) and 20 articles were selected for discussion. Currently, results from these studies showed that PBMCs seem to reflect liver environment and complement adipose tissue findings in transcriptomics. PBMC gene expression after dietary intervention studies can be used for studying the response of certain genes related to fatty acid and cholesterol metabolism, and to explore the response of dietary interventions in relation to inflammation. However, PBMC transcriptomics from dietary intervention studies have not resulted yet in clear confirmation of candidate genes related to disease risk. Use of microarray technology in larger well-designed dietary intervention studies is still needed for exploring PBMC potential in the field of nutrigenomics.
Cardiovascular disease is the major cause of death in the world. Low dietary folate, elevated homocysteine, and high circulating cholesterol are risk factors.
Methods and results
We investigated whether folate and/or B vitamin deficiency would change lipoprotein and fatty acid metabolism and lipid accumulation in the aorta adventitia of ApoE null mice. Mice (n = 10 per group) were fed a control (C; 4%) or high saturated fat (HF; 21%), and high cholesterol (0.15%) diet for 16 weeks. Folate (F-) or folate, B6 and B12 deficiency (F-B-) were imposed on these diets. Feeding a HF diet increased plasma and liver total cholesterol and HDL cholesterol (two- to threefold; p < 0.05). Total cholesterol increased (twofold; p < 0.05) in aorta adventitial lipid in response to HF. Feeding a diet depleted of folate and B vitamins (F-B-) significantly increased cholesterol accumulation in both liver and aorta adventitial lipid (approximately 50–70%; p < 0.05). Moreover, the proportions of fatty acids in hepatic and adventitial lipid was significantly changed by B vitamin depletion, measured as an increase in saturated fatty acids (approximately 15%) and a decrease (approximately 11%) in monounsaturated fatty acids (p < 0.05).
Conclusion
B vitamin deficiency perturbs lipid metabolism in ApoE null mice, causing accumulation of proatherogenic cholesterol and fatty acids in the aorta adventitia.
This study addresses whether early life arachidonic acid (ARA)/docosahexaenoic acid (DHA) supplementation or eicosapentaenoic acid (EPA)/DHA (Omacor) supplementation affects body weight gain, lipid metabolism, and adipose tissue quantity and quality in later life in ApoE*3Leiden-transgenic mice, a humanized model for hyperlipidemia and mild obesity.
Methods and results
Four-week-old male ApoE*3Leiden mice were fed chow diet with or without a mixture of ARA (0.129 wt%) and DHA (0.088 wt%) or Omacor (0.30 wt% EPA, 0.25 wt% DHA). At age 12 weeks, mice were fed high-fat/high-carbohydrate (HFHC) diet without above supplements until age 20 weeks. Control mice received chow diet throughout the study. Mice receiving ARA/DHA gained less body weight compared to control and this effect was sustained when fed HFHC. Omacor had no significant effect on body weight gain. Plasma cholesterol and triglycerides were significantly lowered by both supplementations. At 20 weeks, epididymal fat mass was less in ARA/DHA-supplemented mice, while Omacor had no significant effect on fat mass. Both ARA/DHA and Omacor reduced inguinal adipocyte cell size; only ARA/DHA significantly reduced epididymal macrophage infiltration.
Conclusion
This study shows that early life ARA/DHA, but not Omacor supplementation improves body weight gain later in life. ARA/DHA and to a lesser extent Omacor both improved adipose tissue quality.
As shown in most clinical studies dedicated to carotenoids, there is a huge interindividual variability in absorption, and blood and tissue responses, of dietary carotenoids. The recent discovery that several proteins are involved in carotenoid metabolism in humans has prompted a possible explanation for this phenomenon: genetic variants in genes encoding for these proteins may affect their expression or activity, and in turn carotenoid metabolism and carotenoid status. The proteins clearly identified so far are (i) the carotene oxygenases β,β-carotene-15,15′-monooxygenase (BCMO1) and β,β-carotene-9′,10′-oxygenase (BCDO2), which are involved in carotenoid cleavage, (ii) scavenger receptor class B type I (SR-BI), cluster determinant 36 (CD36), and Niemann Pick C1-like 1 (NPC1L1), which are involved in carotenoid uptake by cells, and (iii) glutathione S-transferase Pi 1 (GSTP1) and human retinal lutein-binding protein (HR-LBP), which are involved in the transport of xanthophylls in the retina. Other proteins, such as ATP-binding cassette subfamily G member 5 (ABCG5) and the fatty acid-binding proteins (FABPs) are also apparently involved although firmer evidence is still required. A genome-wide association study, as well as several candidate gene association studies, has shown that groups of subjects bearing different alleles in single nucleotide polymorphisms located in or near several of the above-mentioned genes display different blood and/or tissue concentrations of carotenoids. Further studies are needed to identify all the proteins involved in carotenoid metabolism and assess whether other types of genetic variation, e.g. copy number variants and epigenetic modifications, can modulate carotenoid status. One potential application of such research could be personalized dietary guidelines for carotenoids according to individual genetic characteristics.
Cardiovascular disease (CVD) is associated with vascular oxidative imbalance and inflammation. Increased reactive oxygen species (ROS) generation is associated with a functional inactivation of nitric oxide (NO) due to the reaction with O−2, leading to peroxynitrite (ONOO−) formation and subsequent reduction in the beneficial effect of vascular NO bioavailability. Carotenoids'-rich diets have been associated with decreased risk of CVD, but the underlying mechanism is still unknown.
Methods and results
In human umbilical vein endothelial cells (HUVECs), both β-carotene (BC) or lycopene (Lyc) significantly affected tumor necrosis factor-α (TNF-α)-induced inflammation, being associated with a significant decrease in the generation of ROS (spectrofluorometry) and nitrotyrosine (an index of ONOO− formation, cytofluorimetry), an increased NO/cGMP (cyclic guanosine monophosphate) levels (EIA), and a down-regulation of NF-κB-dependent adhesion molecule expression (Western blot and EMSA) and monocyte–HUVEC interaction (adhesion assay). Our results indicate that BC or Lyc treatment reduce the inflammatory response in TNF-α-treated HUVECs. This is due to the redox balance protection and to the maintenance of NO bioavailability.
Conclusion
Our observations provide background for a novel mechanism for carotenoids' anti-inflammatory activity in the vasculature and may contribute to a better understanding of the protective effects of carotenoid-rich diets against CVD risk.
Scope: Wheat gluten proteins such as gliadins constitute major food allergens. Gluten can be modified industrially by deamidation which increases its solubility and enhances its use as a food ingredient. Sensitization to deamidated gluten has been reported to cause severe allergic reactions with anaphylaxis. The aim of this study was therefore to compare the sensitization and elicitation potentials of native (NG) and deamidated (DG) gliadins. The reactivity pattern of mice IgE was also compared with that of DG-allergic patients.
Methods and results: The ability of DG to sensitize Balb/c mice using intra-peritoneal administration with aluminium hydroxide as an adjuvant, and to elicit an allergic response after a challenge, was tested in comparison with NG. Mice sensitized with DG secreted higher levels of total IgE, IL-4, gliadin-specific IgE and IgG1 than mice sensitized with NG. By contrast, mice sensitized with NG produced higher levels of gliadin-specific IgG2a and INFγ. After a challenge, histamine levels were higher in mice sensitised with DG.
Conclusions: DG can sensitize mice much more efficiently than NG. Moreover, this mouse model of allergy to DG revealed an IgE reactivity pattern against purified gliadins which was very similar to that of DG-allergic patients.
Scope: The aim of this study was to investigate the antihypertensive effect of a peptide fraction (PepC) obtained from a whey protein concentrate following hydrolysis by Cynara cardunculus, as well as of its fraction with MW below 3 kDa (PepCF). Both these concentrates encompassed peptides that exhibited potent in vitro inhibition of angiotensin-converting enzyme (ACE): two were released from α-lactalbumin – KGYGGVSLPEW and DKVGINYW, and one from β-lactoglobulin – DAQSAPLRVY.
Methods and results: Upon oral administration, by gastric intubation, of 400 mg/kg body weight (bw) of those peptide concentrates, or 5 mg/kg bw of the corresponding synthetic peptides, to 12 wk-old spontaneously hypertensive rats (SHR), the systolic and diastolic blood pressures were monitored by the tail-cuff method – before, and 2, 4, 6, 8 and 24 h afterwards. Water and zofenopril (5 mg/kg bw) – a known ACE-inhibitor, were used as negative and positive controls, respectively. Acute administration of PepC, PepCF, KGYGGVSLPEW, DKVGINYW and DAQSAPLRVY caused antihypertensive effects in SHR; the maximum effect occurred by 4 h and 6 h after administration of the peptide concentrates and the synthetic peptides, respectively. PepC and KGYGGVSLPEW also showed ACE-inhibitory activity in vivo: the pressor effect of angiotensin I was significantly lower, and the response to bradykinin increased when the rats were pre-treated with either product.
Conclusion: Our results strongly suggest that PepC will be effective as nutraceutical ingredient for the formulation of functional foods aimed at hypertension control.
Chlorogenic acid (CA), caffeine (CAFF), pyrogallol (PYR), catechol (CAT), βN-alkanoyl-hydroxytryptamides (C5HT) and N-methylpyridinium (N-MP) were evaluated for their influence on mechanisms of gastric acid secretion as single compounds and in biomimetic mixtures.
Methods and results
Compounds were tested in coffee representative concentrations. Human gastric cancer cells (HGT-1) were used to study the proton secretory activity by Ussing chamber experiments and FACS analysis. For activation of EGFr, Akt1, ERK1/2, ATF-2 and cAMP levels, we performed pathway screening assays. Time-dependent expression of related genes were determined by real-time PCR. Part of the data was used for neural network modeling to identify the most relevant compounds. N-MP increased the expression of the anti-secretory somatostatin receptor by 114%, whereas C5HT decreased its expression by 52%. N-MP down-regulated the pro-secretory CHRM3 receptor by 36% and the H+,K+-ATPase by 36%. CAFF stimulated the secretory activity in the functional assays, whereas N-MP and CA decreased proton secretion. After applying a pathway analysis, we were able to discriminate between CAFF, CA, CAT, C5HT, PYR and histamine-activating EGFr signaling and N-MP-associated ERK1/2 signaling.
Conclusion
By applying a multi-parametric approach, N-MP was shown to effectively down-regulate mechanisms of gastric acid secretion in human parietal gastric cells.
Several insulin receptor substrate-2 (IRS-2) polymorphisms have been studied in relation to insulin resistance and type 2 diabetes. To examine whether the genetic variability at the IRS-2 gene locus was associated with the degree of insulin resistance and plasma fatty acid levels in metabolic syndrome (MetS) subjects.
Methods and results
Insulin sensitivity, insulin secretion, glucose effectiveness, plasma fatty acid composition and three IRS-2 tag-single nucleotide polymorphisms (SNPs) were determined in 452 MetS subjects. Among subjects with the lowest level of monounsaturated (MUFA) (below the median), the rs2289046 A/A genotype was associated with lower glucose effectiveness (p<0.038), higher fasting insulin concentrations (p<0.028) and higher HOMA IR (p<0.038) as compared to subjects carrying the minor G-allele (A/G and G/G). In contrast, among subjects with the highest level of MUFA (above the median), the A/A genotype was associated with lower fasting insulin concentrations and HOMA-IR, whereas individuals carrying the G allele and with the highest level of ω-3 polyunsaturated fatty acids (above the median) showed lower fasting insulin (p<0.01) and HOMA-IR (p<0.02) as compared with A/A subjects.
Conclusion
The rs2289046 polymorphism at the IRS2 gene locus may influence insulin sensitivity by interacting with certain plasma fatty acids in MetS subjects.
In humans, varying amounts of absorbed β-carotene are oxidatively cleaved by the enzyme β,β-carotene 15,15′-monooxygenase 1 (BCMO1) into two molecules of all-trans-retinal. The other carotenoid cleavage enzyme β,β-carotene 9′,10′-dioxygenase (BCDO2) cleaves β-carotene at the 9′,10′ double bond forming β-apo-10′-carotenal and β-ionone. Although the contribution of BCDO2 to vitamin A formation has long been debated, BCMO1 is currently considered the key enzyme for retinoid metabolism. Furthermore, BCMO1 has limited enzyme activity towards carotenoids other than provitamin A carotenoids, whereas BCDO2 exhibits a broader specificity. Both enzymes are located at different sites within the cell, with BCMO1 being a cytosolic protein and BCDO2 being located in the mitochondria. Expression of BCMO1 in tissues other than the intestine has recently revealed its function for tissue-specific retinoid metabolism with importance in embryogenesis and lipid metabolism. On the other hand, biological activity of BCDO2 metabolites has been shown to be important in protecting against carotenoid-induced mitochondrial dysfunction. Single-nucleotide polymorphisms (SNPs) such as R267S and A379V in BCMO1 can partly explain inter-individual variations observed in carotenoid metabolism. Advancing knowledge about the physiological role of these two enzymes will contribute to understanding the importance of carotenoids in health and disease.
There is a consensus that age-related macular degeneration (AMD) is the result of (photo)-oxidative-induced retinal injury and its inflammatory sequelae, the latter being influenced by genetic background. The dietary carotenoids, lutein (L), zeaxanthin (Z), and meso-zeaxanthin (meso-Z), accumulate at the macula, where they are collectively known as macular pigment (MP). The anatomic (central retinal), biochemical (anti-oxidant) and optical (short-wavelength-filtering) properties of this pigment have generated interest in the biologically plausible rationale that MP may confer protection against AMD. Level 1 evidence has shown that dietary supplementation with broad-spectrum anti-oxidants results in risk reduction for AMD progression. Studies have demonstrated that MP rises in response to supplementation with the macular carotenoids, although level 1 evidence that such supplementation results in risk reduction of AMD and/or its progression is still lacking. Although appropriately weighted attention should be accorded to higher levels of evidence, the totality of available data should be appraised in an attempt to inform professional practice. In this context, the literature demonstrates that supplementation with the macular carotenoids is probably the best means of fortifying the anti-oxidant defences of the macula, thus putatively reducing the risk of AMD and/or its progression.
The basis for the vivid color of carotenoids and their antioxidant activity is the multiple conjugated double bonds, which are characteristic for these phytonutrients. Moreover, the cleavage of these oxidation-prone double bonds leads to the formation of apocarotenoids. A large number of carbonyl-containing oxidation products are expected to be produced as a result of carotenoid oxidation and these can be further metabolized into the corresponding acids and alcohols. As discussed in this review, many, but not all, of these potential products have been detected and identified in plants as well as in human and animal plasma and tissues. Some of these compounds were found to be biologically active as anticancer agents. In addition to the inhibition of cancer cell proliferation, several carotenoid metabolites were shown to modulate the activity of various transcription systems. These include ligand-activated nuclear receptors, such as the retinoic acid receptor, retinoid X receptor, peroxisome proliferator-activated receptor and estrogen receptor, as well as other transcription systems that have an important role in cancer, such as the electrophile/antioxidant response element pathway and nuclear factor-κB. Therefore, apocarotenoids can be considered as natural compounds with multifunctional, rather than monofunctional, activity and, thus, can be useful in the prevention of cancer and other degenerative diseases.
Cardiovascular diseases (CVDs) are the leading causes of human morbidity and mortality in developed countries. Specific biomarkers in this context are markers of inflammation, lipid status, thrombosis and oxidative stress. One recommendation for CVD prevention is to increase consumption of fruits and vegetables as good sources of secondary plant products, e.g. carotenoids. This review aimed to show linkages between lycopene, one main carotenoid in the human diet, and prevention of heart diseases by looking for epidemiological data, results from in vitro experiments and results from in vivo studies (animal studies and human intervention trials). In addition, patents and products within the context of lycopene and CVD prevention will be discussed with a special emphasis on health claims. Epidemiological data, in vitro data and results from animal experiments partly showed promising preventive mechanisms of lycopene. In contrast, until now, human intervention studies mostly failed to show any CVD prevention. However, there is still an encouraging situation, giving hints for antioxidant as well as anti-inflammatory effects of lycopene. These mechanisms could be the background for cardio-protective effects of tomatoes and tomato products. In summary, there are a lot of investigations needed in the future to give reliable results to establish these CVD-preventive effects.
While the cardioprotective effect of moderate and regular wine consumption in primary prevention has been well documented, the goal of the present investigation was to explore the effect of wine intake on blood parameters (lipid, anti-oxidant capacity, and erythrocyte membrane potential and fluidity) in post myocardial infarct patients to evaluate perspectives in secondary prevention. A clinical intervention trial has been undertaken on a group of selected post myocardial infarct patients who gave written informed consent for participation in this study prior to enrolment. This two-week study has been conducted on hospitalized patients during a cardiac readaptation period. During this period, patients were submitted to a “Western prudent†diet (inspired by the Mediterranean diet) and two groups have been compared on a drawn basis: patients receiving red wine (250 mL daily) to patients receiving water. Physical, clinical, and blood parameters were evaluated on Days 1 and 14. The data show a positive effect of low wine consumption on blood parameters (decrease in total cholesterol and LDL; increase in erythrocyte membrane fluidity and antioxidant status). The results show that a moderate consumption of red wine even for a short period associated with a “Western prudent†diet improves various blood parameters in lipid and anti-oxidative status in patients with previous coronary ischemic accidents.
Crocus sativus L. (saffron) has been traditionally used for the treatment of insomnia and other diseases of the nervous systems. Two carotenoid pigments, crocin and crocetin, are the major components responsible for the various pharmacological activities of C. sativus L. In this study, we examined the sleep-promoting activity of crocin and crocetin by monitoring the locomotor activity and electroencephalogram after administration of these components to mice. Crocin (30 and 100 mg/kg) increased the total time of non-rapid eye movement (non-REM) sleep by 60 and 170%, respectively, during a 4-h period from 20:00 to 24:00 after its intraperitoneal administration at a lights-off time of 20:00. Crocetin (100 mg/kg) also increased the total time of non-REM sleep by 50% after the administration. These compounds did not change the amount of REM sleep or show any adverse effects, such as rebound insomnia, after the induction of sleep.
Populations that administer highly restrictive diets using a strong dietary regime, excluding certain types of food, might be at risk of vitamin A insufficiency, even in developed countries. Thus, provitamin A carotenoids from plants represent an additional major dietary source of vitamin A for most of the world's population. Our aim was to estimate the contribution of β-carotene to vitamin A supply in industrialized countries using available data from the literature. A total of 11 studies from 8 countries were used, representing data of 121 256 participants. Intakes of total vitamin A, provitamin A carotenoids, including β-carotene were retrieved and used to calculate the retinol activity equivalents (RAE) utilizing current conversion factors. Mean total daily dietary intake of RAE was 1083±175. The mean β-carotene intake was 3.9 mg/day. Preformed vitamin A accounts for nearly 65% of total vitamin A intake, carotenoids make up 35%. No statistical differences between men and women in total intake of retinol were observed. We conclude that a safe vitamin A intake in general cannot be reached by consuming only one component (vitamin A or β-carotene) alone, even in Western countries where animal products are commonly available.
Carotenoids are micronutrients present mainly in fruits and vegetables, and they are ingested from these sources with the diet. They exhibit specific antioxidant activity but also influence signaling and gene expression at the cellular level. β-Carotene and lycopene, the colorants of carrots and tomatoes, respectively, are among the most prominent members of this group of lipids, and they are usually the dominating carotenoids in human blood and tissues. Both compounds modulate skin properties when ingested as supplements or as dietary products. There is evidence that they protect the skin against sunburn (solar erythema) by increasing the basal defense against UV light-mediated damage. Their photoprotective efficacy, however, is not comparable to the use of a sunscreen. In vitro data show that also other carotenoids are efficient photoprotectors. Among them are lutein and structurally unusual phenolic polyenes like 3,3′-dihydroxyisorenieratene.
Molecular mechanisms associated with the anti-/pro-oxidative properties of carotenoids (CARs) are described in organic solvents, micro-heterogeneous environments and model lipid membranes and in cellular suspensions. Singlet oxygen is important in the skin and eye and CARs are efficient singlet oxygen (SO) quenchers with corresponding rate constants near diffusion controlled (typically app. 1010 M−1 s−1) with lycopene (LYC) exhibiting the most efficient quenching in organic solvents. However, in membrane environments there is little or no difference in the quenching efficiency between the dietary CARs. Furthermore, aggregation of CARs, particularly those in the macula (lutein and zeaxanthin), markedly reduces SO quenching efficiency. Free radical interactions with CARs leads to at least three processes, electron and hydrogen atom transfer and adduct formation. The most studied is electron transfer where the CAR loses an electron to become a radical cation. The reactivity/lifetime of such CAR radicals may lead to a switch from anti- to pro-oxidant behaviour of CARs. These reactions are related to CAR redox potentials with LYC being the lowest (most easily oxidised) allowing LYC to reduce/repair all other CAR radical cations and LYC ‘sacrificed’ where mixtures of CARs are present in oxidative environments. Such redox-controlled reactions may lead to deleterious as well as beneficial health effects.
The antioxidant activity and phenolic compound profiles of six fractions (I–VI) obtained from sunflower seed extract were
studied. HPLC–MS(ESI) analysis was applied for quantitative and qualitative determination of phenolic compounds of the fractions.
The antioxidant activity of the fractions was studied in terms of their ability to scavenge DPPH· and ABTS·+ and to reduce Fe3+/ferricyanide complex to the ferrous form and was expressed as EC50, TEAC and reducing power values, respectively. The results of all antioxidant activity tests showed good correlations among
each other and with the phenolic contents for the individual fractions. The fractions IV–VI were characterized by high antioxidant
activity. 5-O-Caffeoylquinic acid was a predominant compound of fractions IV and V, while dicaffeoylquinic acid isomers and caffeoyl-dimethoxycinnamoylquinic
acid isomers accounted for 76.6 % of phenolic compounds of fraction VI. Ferulic acid, p-coumaroylquinic acid isomers, ferulic acid dehydrotrimer isomers and some quercetin derivatives were also identified. The
highest content of those compounds was noted in fraction III.
Content Type Journal Article
Category Original Paper
Pages 1-10
DOI 10.1007/s00217-012-1751-6
Authors
Magdalena Karamać, Division of Food Sciences, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Tuwima 10, 10-748 Olsztyn, Poland
Agnieszka Kosińska, Division of Food Sciences, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Tuwima 10, 10-748 Olsztyn, Poland
Isabel Estrella, Instituto de Ciencia y TecnologÃa de Alimentos y Nutrición, CSIC, Juan de la Cierva 3, 28006 Madrid, Spain
Teresa Hernández, Instituto de Ciencia y TecnologÃa de Alimentos y Nutrición, CSIC, Juan de la Cierva 3, 28006 Madrid, Spain
Montserrat Dueñas, Polyphenols Research Group, Unidad de Nutrición y BromatologÃa, Facultad de Farmacia, Universidad de Salamanca, Campus Miguel de Unamuno, 37007 Salamanca, Spain
Biogenic amines (histamine, tyramine, putrescine, cadaverine, agmatine, spermidine and spermine) are nitrogenous compounds.
They occur naturally in living organisms and are involved in many biological processes. Nonetheless, high amounts in food
may be hazardous to human health. The diamines putrescine and cadaverine in food can potentiate the effects of simultaneously
ingested histamine. In protein-rich foods, high concentrations of these diamines are indicative for hygienic deficiencies
in the food chain. Even though being formed endogenously and being essential for some physiological metabolic pathways, both
diamines are known as precursors for carcinogenic nitrosamines. Putrescine also plays a certain role in tumour growth. Nevertheless,
no tolerable levels in foods have been established so far. The present study suggests tolerable levels in cheese, fermented
sausages, fish, sauerkraut and seasonings that are based on toxicological threshold levels, occurrence of diamines in foods
and food consumption in Austria. Average daily intake of putrescine via fermented food was calculated to be 6.8 (female adults)
and 8.8 (male adults) mg per person. Respective numbers for cadaverine were 9.8 and 11.6 mg per person and day. For putrescine,
proposed maximum tolerable levels for sauerkraut, fish, cheese, fermented sausages and seasonings are 140, 170, 180, 360 and
510 mg/kg, respectively. Likewise, for cadaverine, in sauerkraut, fish, cheese, fermented sausages and seasonings, maximum
tolerable levels are 430, 510, 540, 1,080 and 1,540 mg/kg, respectively. These limits can be met by current manufacturing
practices, as ascertained from the results of our own studies and from literature. Admittedly, only few data are published
on toxicological threshold levels of these diamines, which mean that these tolerable levels are associated with some uncertainty.
Content Type Journal Article
Category Original Paper
Pages 1-12
DOI 10.1007/s00217-012-1748-1
Authors
Elke Rauscher-Gabernig, Data, Statistics and Risk Assessment, Austrian Agency for Health and Food Safety, Spargelfeldstrasse 191, 1220 Vienna, Austria
Robert Gabernig, Institute for Food Safety Vienna, Austrian Agency for Health and Food Safety, Spargelfeldstrasse 191, 1220 Vienna, Austria
Werner Brueller, Data, Statistics and Risk Assessment, Austrian Agency for Health and Food Safety, Spargelfeldstrasse 191, 1220 Vienna, Austria
Roland Grossgut, Data, Statistics and Risk Assessment, Austrian Agency for Health and Food Safety, Spargelfeldstrasse 191, 1220 Vienna, Austria
Friedrich Bauer, Institute of Meat Hygiene, Meat Technology and Food Science in the Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210 Vienna, Austria
Peter Paulsen, Institute of Meat Hygiene, Meat Technology and Food Science in the Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210 Vienna, Austria
An analytical protocol was developed for investigating short-chain aliphatic amines occurrence in waxes for fruit coating
with the aim of controlling their commercialization in countries where the use of these carriers is forbidden. Six short-chain
aliphatic amines (morpholine, diethanolamine, triethylamine, 2-dimethylaminoethanol, triethanolamine and 3-metoxypropylamine)
were detected by LC/MS/MS operating in positive ion mode in fortified waxes after a two-step clean-up procedure. The analytical
method was statistically validated. The matrix-matched regression lines showed r2 > 0.97. Recoveries ranging from 92 to 114 % were obtained for the fortification level of 3.5 % w/w and the relative standard
deviations ranged from 2 to 8 % (n = 6). The limits of detection were below 0.2 % w/w, while the limits of quantification did not exceed 0.5 % w/w. The method
is currently applied in ICQRF Laboratory of Catania on samples of coating waxes collected in the Italian market in the frame
of MIPAAF institutional quality control activity.
Content Type Journal Article
Category Original Paper
Pages 1-8
DOI 10.1007/s00217-012-1749-0
Authors
Leonardo Sabatino, Ministero delle Politiche Agricole Alimentari e Forestali (MIPAAF), Dipartimento dell’Ispettorato centrale della tutela della qualità e della repressione frodi dei prodotti agroalimentari (ICQRF), Laboratorio di Catania, Via A. Volta 19, 95122 Catania, Italy
Monica Scordino, Ministero delle Politiche Agricole Alimentari e Forestali (MIPAAF), Dipartimento dell’Ispettorato centrale della tutela della qualità e della repressione frodi dei prodotti agroalimentari (ICQRF), Laboratorio di Catania, Via A. Volta 19, 95122 Catania, Italy
Rosario Caruso, Ministero delle Politiche Agricole Alimentari e Forestali (MIPAAF), Dipartimento dell’Ispettorato centrale della tutela della qualità e della repressione frodi dei prodotti agroalimentari (ICQRF), Laboratorio di Catania, Via A. Volta 19, 95122 Catania, Italy
Elena Chiappara, Ministero delle Politiche Agricole Alimentari e Forestali (MIPAAF), Dipartimento dell’Ispettorato centrale della tutela della qualità e della repressione frodi dei prodotti agroalimentari (ICQRF), Laboratorio di Catania, Via A. Volta 19, 95122 Catania, Italy
Pasqualino Traulo, Ministero delle Politiche Agricole Alimentari e Forestali (MIPAAF), Dipartimento dell’Ispettorato centrale della tutela della qualità e della repressione frodi dei prodotti agroalimentari (ICQRF), Laboratorio di Catania, Via A. Volta 19, 95122 Catania, Italy
Adalgisa Belligno, Dipartimento di Scienze delle Produzioni Agrarie e Alimentari (DISPA), Università degli Studi di Catania, Via S. Sofia 98, 95123 Catania, Italy
Giacomo Gagliano, Ministero delle Politiche Agricole Alimentari e Forestali (MIPAAF), Dipartimento dell’Ispettorato centrale della tutela della qualità e della repressione frodi dei prodotti agroalimentari (ICQRF), Laboratorio di Catania, Via A. Volta 19, 95122 Catania, Italy
Analytical methods for selenium (Se) speciation were developed using high-performance liquid chromatography (HPLC) coupled
to either inductively coupled plasma mass spectrometry (ICP–MS) or electrospray ionization tandem mass spectrometry (ESI–MS/MS).
Separations of selenomethionine (Se-Met) and selenocysteine (Se-(Cys)2) with favorable peak shape and resolution were obtained by both HPLC-ICP-MS and HPLC–ESI–MS/MS. Both methods achieved low
limits of detection, high sensitivity and favorable stability. With HPLC–ESI–MS/MS, signal suppression was observed when complex
matrix was co-eluted, but excellent structural characterization was still achieved. Thus, HPLC-ICP-MS is better for the detection
of Se species, and HPLC–ESI–MS/MS is essential for molecular identification and confirmation. A water-soluble selenoprotein
from purified M. anguillicaudatus muscle tissue was analyzed by the two complementary systems (HPLC-ICP-MS and HPLC–ESI–MS/MS) with high sensitivity and accuracy.
The results demonstrated that Se-Met was the predominant selenoamino acid in the purified selenoprotein from M. anguillicaudatus muscle tissue, and the concentration of Se-Met in the selenoprotein was 6.280 mg/kg (dry mass). In addition, in HPLC-ICP-MS,
an unknown Se-containing compound with similar polarity to Se-(Cys)2 was discovered. Using complementary data from HPLC–ESI–MS/MS, it was determined that this unknown Se-containing compound
was not Se(Cys)2.
Content Type Journal Article
Category Original Paper
Pages 1-8
DOI 10.1007/s00217-012-1747-2
Authors
Like Gong, College of Food Science and Biotechnology, Zhejiang Gongshang University, 310035 Hangzhou, Zhejiang Province, China
Qingbing Xu, College of Food Science and Biotechnology, Zhejiang Gongshang University, 310035 Hangzhou, Zhejiang Province, China
Charles Lee, USDA-ARS, 800 Buchanan St., Albany, CA 94710, USA
Hong Zhang, College of Food Science and Biotechnology, Zhejiang Gongshang University, 310035 Hangzhou, Zhejiang Province, China
This paper reports the effect of high hydrostatic pressure (HHP) on wines contaminated with Dekkera/Brettanomyces populations of 104 and 106 cfu mL−1 growing at either pH 3.2 or 3.6 (both normal pHs for red wine) and at room temperature (25 °C). HHP (100 MPa for 24 h) was
highly effective at controlling the growth of all combinations of starting yeast population and pH, yet caused scant modification
of thermosensitive wine molecules such as pigments and volatile compounds (molecules that greatly influence wine quality).
The present results support the potential use of HHP as a means of cold-pasteurising wines to control Dekkera/Brettanomyces.
The influence of co-winemaking technique on the phenolic profiles, color and antioxidant capacity of wines made from red grape
varieties cultivated in La Mancha region (Spain) was investigated. Co-winemaking red wines were obtained by pre-fermentative
blend of grapes (1:1, w/w) from the predominant Cencibel (Tempranillo) variety in this region and the minor varieties Bobal,
Moravia Agria, Moravia Dulce, Tortosà and Rojal, together with a three varieties blend (1:1:1, w/w/w) of Cencibel, Bobal and
Moravia Agria grapes. The phenolic profiles obtained in co-winemaking wines showed more quantity of different compounds than
single-variety wine of Cencibel used as reference. The best results were obtained using Bobal, Moravia Agria and Moravia Dulce
varieties for co-winemaking, especially an improvement of color characteristics. All co-winemaking wines significantly increased
the total resveratrol content as compared to the Cencibel reference wine, although cis-isomers largely predominated in all wines. Moravia Agria and Rojal varieties produced co-winemaking wines with decreased
antioxidant capacity, whereas Bobal and Moravia Dulce varieties increased it, even when the co-winemaking wine from Moravia
Dulce contained less total polyphenols than Cencibel reference wine. Co-winemaking technique can be suggested as a way to
widen the offer of wines to consumers, incorporating characteristic properties of minor grape varieties. In addition, this
enological technique has the benefit of avoiding the disappearance of native species, thus improving the biodiversity of La
Mancha region.
The effect of structurally different bacterial homoexopolysaccharides on gluten-free bread quality and their properties to
act as hydrocolloids was investigated. Furthermore, exopolysaccharides (EPS) were analyzed structurally by asymmetrical flow
field flow fractionation and methylation analysis. Breads were made of buckwheat and rice flour with EPS of Lactobacillus (L.) curvatus TMW 1.624, L. reuteri TMW 1.106, L. animalis TMW 1.971, and L. sanfranciscensis TMW 1.392 or hydroxypropylmethylcellulose (HPMC) at 1 % w/w flour base. Water-holding capacity, specific volume, crumb analysis,
baking loss, moisture content, and crumb hardness were determined. Only HPMC and the glucan of L. curvatus TMW 1.624 retained water, and all supplements increased the specific volume. Furthermore, crumb hardness was decreased by
additives to different extents. The moisture content, baking loss, and crumb firmness were improved most by dextran of L. curvatus TMW 1.624. Structure analysis of EPS revealed that L. animalis TMW 1.971 produces a fructan and a glucan and that the dextran of L. curvatus TMW 1.624 had highest molecular weight of analyzed EPS, ranging from 118 to 242 MDa. A methylation analysis demonstrated
differences in branching. Dextran of L. reuteri TMW 1.106 is branched in position 4 (18–19 %), whereas dextran of L. curvatus TMW 1.624 is branched in position 3 (8–9 %). Overall, this study gives insight into structure function relations of different
EPS. A structure function relation is suggested in which high weight average molar mass (Mw) and branching at position 3 of
the glucose monomer foster a compact conformation of the molecule, which enables an increased water-binding capacity and promotes
superior (structural) effects in gluten-free breads. The dextran of L. curvatus TMW 1.624 was the most promising candidate for applications in gluten-free bread quality improvements as it retains its size
distribution and root mean square even with increasing Mw and forms an increasingly compact molecule.
The results of a joint European enforcement campaign are described. The two governmental food control laboratories in Stuttgart/Germany
and Zürich/Switzerland analyzed the migration of the plasticizers from the gaskets of lids into food in glass jars for 411
products collected by the authorities of 21 European countries. Of these products, 308 contained free edible oil in contact
with the gasket and were considered relevant for further evaluation. In 74 of the relevant products (24 %), either non-authorized
plasticizers had been used or the migration exceeded the legal limits, in some cases for several parameters and by up to more
than a factor of 10. Most of the products were 1–4 years from the end of their shelf life. Taking into account that migration
proceeds throughout storage, sometimes even accelerates, limits are likely to be exceeded for many more products by the end
of the shelf life. Polyadipate showed the lowest migration. Promising gaskets are either plasticized exclusively with a polyadipate
or with combinations of substances. Joint enforcement is cost-effective, particularly when chemical analysis is demanding;
accumulation of experience facilitates the evaluation of results, and joint measures are promising to be more effective.
Content Type Journal Article
Category Original Paper
Pages 1-9
DOI 10.1007/s00217-012-1739-2
Authors
Gregor McCombie, Official Food Control Authority of the Canton of Zürich, P.O. Box 1471, 8032 Zurich, Switzerland
This study presents the influence of calcium lactate treatment (0–6 %) and cellular composition on two mechanical attributes:
firmness and total acoustic emission (AE) events registered in the puncture test of apple tissue. The experiment was performed
on five apple cultivars stored for nine months in a normal or controlled atmosphere. The microstructure was characterized
quantitatively on control samples by confocal scanning laser microscope followed by image analysis. The mean area and perimeter
of detected objects, which were either cells or spaces, and estimated cell wall fraction were used for the characterization
of the tissue microstructure. Treatment with increased Ca2+ concentration caused a significant increase in firmness and total AE events. The increase was more pronounced in the case
of total AE events which better reflected an increase in brittleness of apple tissue than firmness parameter. The effect was
particularly positive in the case of very soft apples (stored in a normal atmosphere) due to greater extent of de-esterification
of homogalacturonan. Analysis of the results, together with a review of the literature, suggests that calcium importantly
changes the cracking mode of tissue, from intercellular debonding to cell wall rupturing. Firmness and the total AE events
significantly relate negatively to the object’s size and positively to estimated cell wall fraction. A rough accordance of
the number of split cells open across cell walls by puncture probe and the total AE events registered in the test, which was
saturated in high Ca2+ concentrations, was noticed.
Content Type Journal Article
Category Original Paper
Pages 1-10
DOI 10.1007/s00217-012-1743-6
Authors
Justyna Cybulska, Institute of Agrophysics, Polish Academy of Sciences, Doswiadczalna 4, 20-290 Lublin 27, Poland
Piotr Mariusz Pieczywek, Institute of Agrophysics, Polish Academy of Sciences, Doswiadczalna 4, 20-290 Lublin 27, Poland
Artur Zdunek, Institute of Agrophysics, Polish Academy of Sciences, Doswiadczalna 4, 20-290 Lublin 27, Poland
Numerous bread-like gluten-free products have been lately developed due to the rising demand on wheat-free foods. A range
of parameters has been used to describe these products, but there is no general agreement about the most suitable assessment
to characterize them. The objective of this research was to characterize diverse gluten-free like breads (GFB) in order to
discriminate them and to establish possible correlations among descriptive parameters of GFB features determined by instrumental
methods and sensory analysis. Statistical analysis showed that all physical, physicochemical characteristics (specific volume,
moisture content, water activity,
L*
,
a*
,
b*
, hue and chroma), hydration properties (swelling, water holding capacity and water binding capacity), texture profile analysis
parameters (hardness, springiness, chewiness, cohesiveness and resilience), and structural analysis of the crumbs (number
of cells and total area) significantly (p < 0.05) discriminated between the GFB types tested. Sensory analysis revealed great divergences in crumb appearance, odor,
springiness, crumbliness, and color of samples, but no significant differences (p < 0.05) in flavor, aftertaste, and hardness of them. Certain significant correlations were established within the parameters
determined by instrumental methods. Hydration properties of the crumb showed positive correlations with cohesiveness and resilience.
Significant correlations, but scientifically meaningless, were observed among the instrumental and sensory parameters, because
correlation coefficients were rather low, which represent very weak or low linear correlations (r ≤ 0.35). The principal component analysis showed that sensory parameters described in this study and also hydration properties
besides texture parameters would be suitable for characterizing bread-like gluten-free products.
Content Type Journal Article
Category Original Paper
Pages 1-11
DOI 10.1007/s00217-012-1736-5
Authors
MarÃa Estela Matos, Institute of Agrochemistry and Food Technology, CSIC, Av. Agustin Escardino, 7. Paterna, 46980 Valencia, Spain
Cristina M. Rosell, Institute of Agrochemistry and Food Technology, CSIC, Av. Agustin Escardino, 7. Paterna, 46980 Valencia, Spain
The Maillard reaction product 6-(2-formyl-1-pyrrolyl)-l-norleucine (formyline) was recently identified as a new pyrrole amino acid resulting from the reaction of free and protein-bound
lysine residues with the 1,2-dicarbonyl compound 3-deoxypentosone, pentose sugars, and degradation products of disaccharides.
In the present work, simultaneous analysis of formyline and its structural analog, pyrraline, in enzymatically hydrolyzed
food matrices was achieved on an RP-phenyl column by high-pressure liquid chromatography (HPLC) with UV detection. The presence
of formyline was for the first time unequivocally verified in the hydrolyzates and standard samples by HPLC coupled to triple
quad mass spectrometry due to identity of product ion spectra after targeted fragmentation of the molecular ion of formyline.
A total of 68 food samples were analyzed. Low concentrations of formyline were detected in milk and whey products. In breakfast
cereals, pasta, and bakery products, formyline was quantified in concentrations up to 34.8 mg/kg. In the outmost bread crust,
0.6 % of lysine residues can be modified to formyline. Moreover, it was shown by analysis of concentrated beer samples that
both formyline and pyrraline are constituents of beer proteins. From our data, we conclude that at least 2–3 mg of formyline
and 20–40 mg of pyrraline are ingested with the daily diet.
Content Type Journal Article
Category Original Paper
Pages 1-8
DOI 10.1007/s00217-012-1738-3
Authors
Michael Hellwig, Institute of Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany
Thomas Henle, Institute of Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany
The purpose of this study was to investigate and compare the physicochemical properties of fish protein isolate (FPI) produced
from silver carp (Hypophthalmichthys molitrix), which is a relatively cheap fish with low consumption in Fars (a state of Iran). In this research, proteins were isolated
using pH shifts method. Results showed that in terms of production efficiency, protein recovery, lipid reduction and functional
properties such as water-holding capacity, emulsifying capacity, foaming capacity and water absorption, FPI was better than
conventional surimi. The treated samples at pH = 2.5 represented better functional properties relative to other samples. The
electrophoretic patterns demonstrated that acidic pH led to vanish high molecular weight protein bands because these proteins
were converted to low molecular weight proteins, whereas basic pH caused the formation of high molecular weight proteins relative
to myosin heavy chain. It seems that in basic pH, the proteins were linked together after denaturation and then aggregated.
Overall, the results showed that physicochemical qualitative properties of FPI were better than those of conventional surimi.
Content Type Journal Article
Category Original Paper
Pages 1-8
DOI 10.1007/s00217-012-1721-z
Authors
Mohsen Azadian, Department of Food Science and Technology, Shiraz University, Shiraz, Iran
Marzieh Moosavi-Nasab, Department of Food Science and Technology, Shiraz University, Shiraz, Iran
Elahe Abedi, Department of Food Science and Technology, Shiraz University, Shiraz, Iran
Although whey protein hydrolysate (WPH) possesses good physiological functionality, its bitter taste and hygroscopic property
limit its direct utilization as food ingredient. The aim of this work was to encapsulate whey protein hydrolysate by spray
drying using maltodextrin or maltodextrin/β-cyclodextrin mixture as wall materials to attenuate the bitter taste and enhance the stability of whey protein hydrolysate.
Hygroscopicity, glass transition temperature, bitter taste, and morphology of non-encapsulated WPH and encapsulated WPH were
evaluated. Solubility, particle size, bulk density, and moisture content were also measured. Compared with the non-encapsulated
WPH, the encapsulated WPH exhibited significantly lower hygroscopicity and higher glass transition temperature. The bitterness
of both maltodextrin-encapsulated WPH and maltodextrin/β-cyclodextrin-encapsulated WPH was significantly lower than that of the original non-encapsulated WPH. Morphological analysis
by scanning electron microscopy showed that the microcapsules of the spray-dried encapsulated WPH were matrix-type with less
link bridge and had a continuous wall with many concavities. In addition, encapsulation process did not exert negative effect
on the solubility of whey protein hydrolysate. The results indicated that encapsulation with maltodextrin and β-cyclodextrin as carriers was helpful to attenuate the bitter taste and enhance the stability of whey protein hydrolysate.
Content Type Journal Article
Category Original Paper
Pages 1-7
DOI 10.1007/s00217-012-1735-6
Authors
Shu Yang, College of Food Science and Nutritional Engineering, Key Laboratory of Functional Dairy, Ministry of Education, China Agricultural University, Beijing, 100083 People’s Republic of China
Xue-Ying Mao, College of Food Science and Nutritional Engineering, Key Laboratory of Functional Dairy, Ministry of Education, China Agricultural University, Beijing, 100083 People’s Republic of China
Fei-Fei Li, College of Food Science and Nutritional Engineering, Key Laboratory of Functional Dairy, Ministry of Education, China Agricultural University, Beijing, 100083 People’s Republic of China
Dan Zhang, College of Food Science and Nutritional Engineering, Key Laboratory of Functional Dairy, Ministry of Education, China Agricultural University, Beijing, 100083 People’s Republic of China
Xiao-Jing Leng, College of Food Science and Nutritional Engineering, Key Laboratory of Functional Dairy, Ministry of Education, China Agricultural University, Beijing, 100083 People’s Republic of China
Fa-Zheng Ren, College of Food Science and Nutritional Engineering, Key Laboratory of Functional Dairy, Ministry of Education, China Agricultural University, Beijing, 100083 People’s Republic of China
Guo-Xin Teng, Beijing Sanyuan Foods Co. LTD, Beijing, 102206 People’s Republic of China
The aim of this study was to investigate the activity of lipoxygenase extracted from Lupinus angustifolius seeds and its interactions with native lupin polyphenols. The examinated enzyme is active at pH 7.5 causing peroxidation
of linoleic acid. The main hydroperoxide produced in the presence of investigated lupin lipoxygenase was 13-hydroperoxy-octadecadienoic
acid (13-HPODE t-t). In the presence of the phenolic compounds extracted from L. angustifolius seeds, the changes of lipoxygenase activity were observed. A distinct antioxidant effect of lupin polyphenols observed at
their low concentration (0.58 μg/ml) was almost completely overcome at higher concentration of phenolic compounds (2.91 μg/ml).
It comes probably from oxidation of polyphenols in the presence of lupin lipoxygenase. In this mechanism, polyphenol radical
formation is possible. The formed radicals decrease the antioxidant efficiency of the phenolic compounds. Eventual phenoxyl
radical-mediated peroxidation may be inhibited by the presence of antioxidants able to regenerate flavonoids.
Content Type Journal Article
Category Original Paper
Pages 1-7
DOI 10.1007/s00217-012-1737-4
Authors
Jaroslaw Czubinski, Department of Food Biochemistry and Analysis, Poznan University of Life Sciences, Wojska Polskiego 28, 60-637 Poznan, Poland
Krzystof Dwiecki, Department of Food Biochemistry and Analysis, Poznan University of Life Sciences, Wojska Polskiego 28, 60-637 Poznan, Poland
Aleksander Siger, Department of Food Biochemistry and Analysis, Poznan University of Life Sciences, Wojska Polskiego 28, 60-637 Poznan, Poland
Eleonora Lampart-Szczapa, Department of Food Biochemistry and Analysis, Poznan University of Life Sciences, Wojska Polskiego 28, 60-637 Poznan, Poland
Malgorzata Nogala-Kalucka, Department of Food Biochemistry and Analysis, Poznan University of Life Sciences, Wojska Polskiego 28, 60-637 Poznan, Poland
The effect of different light conditions on the specificity and reliability of thermoluminescence (TL) analysis to detect
irradiated samples (potatoes and garlic) during 2 years of storage was investigated. The silicate minerals separated from
the nonirradiated samples provided a low-intensity TL glow curve with a maximum peak after 300 °C demonstrating the absence
of an irradiation history. The TL glow curve from the irradiated samples provided easy discrimination with TL glow curves
of high intensity and maximum peak in temperatures range of 160–185 °C. The results were also confirmed by calculating the
TL ratio (TL1/TL2) through normalization (re-irradiation) step. The key parameters of the TL analysis including the TL intensity, TL glow curve
shape, and the TL ratio exhibited a time-dependent change. The bleaching effect of different light conditions was also significant,
which was most prominent in the case of natural light with a prominent decrease in the TL intensity and ratio. The maximum
TL glow peak also showed a shift towards the higher temperature. However, all irradiated samples, irrespective of the storage
conditions and time, were easily discernable from the nonirradiated ones considering the shape and intensity of the TL glow
curve.
Content Type Journal Article
Category Original Paper
Pages 1-8
DOI 10.1007/s00217-012-1740-9
Authors
Jae-Jun Ahn, Department of Food Science and Technology, Kyungpook National University, Daegu, 702-701 Republic of Korea
Gui-Ran Kim, Department of Food Science and Technology, Kyungpook National University, Daegu, 702-701 Republic of Korea
Kashif Akram, Department of Food Science and Technology, Kyungpook National University, Daegu, 702-701 Republic of Korea
Jeong-Sook Kim, Department of Food Nutrition and Culinary, Keimyung College, Daegu, 704-703 Republic of Korea
Joong-Ho Kwon, Department of Food Science and Technology, Kyungpook National University, Daegu, 702-701 Republic of Korea
In the European Union, labelling of the 14 food allergens listed in Annex IIIa of Directive 2000/13/EC is mandatory. The implementation
of upper limits for these allergens is under discussion. Therefore, quantitative analytical methods will be needed to verify
compliance with regulatory requirements and to provide an improved basis for the legal assessment of allergen labelling. In
this study, the lupine flour content in wheat flours was determined using real-time PCR and statice seeds as internal standard
material. The method proved to be applicable to the quantification of lupine contents from 1 to 10 mg/kg, which is in the
range relevant for allergic consumers.
It is known that conjugated linoleic acid (CLA) isomers have different beneficial health effects, and it has been demonstrated
that the effects of CLA may be isomer dependent. For this reason, CLA isomer fractionation is a very important topic, and
recently, various enzymatic methods for the fractionation of CLA isomers have been studied. In this paper, a commercial CLA
standard including four isomers (c11,t13-, t10,c12-, c9,t11- and t8,c10-CLA) were subjected to enzymatic esterification with l-menthol in order to examine the ability of Candida rugosa lipase to discriminate among the isomers. The lipase was incubated at 30 °C for different reaction times, and subsequently,
the degree of enzymatic esterification was established by high-performance liquid chromatography (HPLC) with light scattering
detection. Moreover, in this study, a silver–ion HPLC analysis was developed to determine the isomer profile of l-menthyl-CLA. Since the t8,c10- and c11,t13-CLA isomers are not commercially available, they were obtained by sigmatropic rearrangement of c9,t11- and t10,c12-CLA, respectively. The highest selectivity for the c9,t11-CLA isomer was obtained when enzymatic esterification was carried out for 8 h. This study demonstrated that C. rugosa lipase has a higher selectivity for cis,trans isomers, than for trans,cis isomers; in particular, it has a higher selectivity for c9,t11- than for c11,t13-CLA.
Content Type Journal Article
Category Original Paper
Pages 1-7
DOI 10.1007/s00217-012-1731-x
Authors
Laura Giua, Department of Agricultural Economics and Food Sciences, Food Chemistry Section, University of Perugia, 06126 Perugia, Italy
Lina Cossignani, Department of Agricultural Economics and Food Sciences, Food Chemistry Section, University of Perugia, 06126 Perugia, Italy
Maria Stella Simonetti, Department of Agricultural Economics and Food Sciences, Food Chemistry Section, University of Perugia, 06126 Perugia, Italy
Germana Lombardi, Department of Agricultural Economics and Food Sciences, Food Chemistry Section, University of Perugia, 06126 Perugia, Italy
Francesca Blasi, Department of Agricultural Economics and Food Sciences, Food Chemistry Section, University of Perugia, 06126 Perugia, Italy
A real-time PCR allelic discrimination TaqMan assay based on the analysis of a single nucleotide polymorphism enabling the
differentiation of cow (Bos taurus) and donkey (Equus asinus) milk was developed. Specific primers and probes were designed on the mitochondrial cytochrome c oxidasesubunit I gene. The primers were designed upstream and downstream the chosen diagnosis site in a conserved region. Two probes were
designed to specifically hybridise to B. taurus and E. asinus sequences. The test allowed the discrimination of bovine and donkey DNA in all blood and pure milk samples giving an unambiguous
result plot of rapid and easy interpretation. The detection threshold was 2 % of cow milk in donkey milk. The applicability
of the method to matrices containing degraded DNA was demonstrated by analysing samples of raw donkey and cow milk autoclave-treated
(121 °C for 15 min). Finally, the assay when applied to milk samples collected from the retail trade has confirmed the species
indicated in the label. Furthermore, the assay represents a potentially valuable diagnostic tool for species identification
in dairy products for allergic people.
Content Type Journal Article
Category Original Paper
Pages 1-6
DOI 10.1007/s00217-012-1732-9
Authors
Alessandra Dalmasso, Department of Animal Pathology, University of Turin, via Leonardo da Vinci 44, 10095 Grugliasco, TO, Italy
Paola Sacchi, Department of Animal Production Epidemiology and Ecology, University of Turin, via Leonardo da Vinci 44, 10095 Grugliasco, TO, Italy
Maria Teresa Bottero, Department of Animal Pathology, University of Turin, via Leonardo da Vinci 44, 10095 Grugliasco, TO, Italy
The influence of ante-mortem hypoxia on physicochemical stability of white shrimp (Litopenaeus vannamei) muscle exposed to multiple freeze–thaw (F/T) cycles was evaluated. Results showed 5.7 and 10.8% decrements in water-holding
capacity and myofibrillar protein solubility, respectively, for stressed shrimp during the first F/T cycle compared to control.
Significant differences (P ≤ 0.05) on myosin Tmax were found comparing stressed and control fresh shrimp with a 1.4 °C increased on stressed fresh shrimp; however, no differences
were found on ΔH values. With regard to stressed fresh shrimp actin, Tmax increased (P ≤ 0.05) 0.8 °C, while ΔH decreased (P ≤ 0.05) by 0.12 J g−1, respectively. Regardless of the results found in fresh shrimp, no differences were found for myosin Tmax and ΔH between stressed and control during the F/T cycles. SDS-PAGE showed no relevant changes induced by autolysis during the experiment.
Histological analysis showed an increase of 257% in blank area of stressed fresh shrimp when comparing to control. Results
showed the influence of ante-mortem hypoxia on the stability of fresh shrimp myofibrillar proteins, affecting its physicochemical
properties. In contrast, for shrimp exposed to F/T cycles, the hypoxia effect was not relevant.
Content Type Journal Article
Category Original Paper
Pages 1-9
DOI 10.1007/s00217-012-1702-2
Authors
H. E. RamÃrez-Guerra, Laboratorio de BioquÃmica y Calidad de Productos Pesqueros, Centro de Investigación en Alimentación y Desarrollo A.C. (CIAD), Carretera a La Victoria km 0.6, P.O. Box 1735, 83000 Hermosillo, Sonora, Mexico
C. O. GarcÃa-Sifuentes, Laboratorio de BioquÃmica y Calidad de Productos Pesqueros, Centro de Investigación en Alimentación y Desarrollo A.C. (CIAD), Carretera a La Victoria km 0.6, P.O. Box 1735, 83000 Hermosillo, Sonora, Mexico
R. Pacheco-Aguilar, Laboratorio de BioquÃmica y Calidad de Productos Pesqueros, Centro de Investigación en Alimentación y Desarrollo A.C. (CIAD), Carretera a La Victoria km 0.6, P.O. Box 1735, 83000 Hermosillo, Sonora, Mexico
J. C. Ramirez-Suarez, Laboratorio de BioquÃmica y Calidad de Productos Pesqueros, Centro de Investigación en Alimentación y Desarrollo A.C. (CIAD), Carretera a La Victoria km 0.6, P.O. Box 1735, 83000 Hermosillo, Sonora, Mexico
M. E. Lugo-Sánchez, Laboratorio de BioquÃmica y Calidad de Productos Pesqueros, Centro de Investigación en Alimentación y Desarrollo A.C. (CIAD), Carretera a La Victoria km 0.6, P.O. Box 1735, 83000 Hermosillo, Sonora, Mexico
S. M. Scheuren-Acevedo, Laboratorio de BioquÃmica y Calidad de Productos Pesqueros, Centro de Investigación en Alimentación y Desarrollo A.C. (CIAD), Carretera a La Victoria km 0.6, P.O. Box 1735, 83000 Hermosillo, Sonora, Mexico
Nitrogen has a significant effect on the fermentation rate and the chemical composition of alcoholic beverages. Nitrogen deficiency
during fermentation of Agave juice for mescal production can lead to slow fermentations and end-products with low aromatic compound variety. In this study,
the effects of NH4Cl supplementation on volatile compound formation in Agaveduranguensis juice fermented at 28 °C with the native yeast strains Saccharomycescerevisiae ITD00185, Hanseniasporauvarum ITD00108, Torulasporadelbrueckii ITD00110 and Kluyveromycesmarxianus ITD00211 were analysed. Nitrogen content in the Agave juice unsupplemented with NH4Cl was low. In the control treatments, the four yeasts consumed nitrogen at approximately the same rate, almost completely
finishing by 24 h. Nitrogen supplementation increased biomass production with S.cerevisie, H.uvarum and T.delbrueckii but not with K.marxianus. K.marxianus consumed the total assimilable nitrogen more slowly than the other strains in the supplemented fermentations. In addition,
the volatile compound profile differed between the studied yeasts. Volatile compound production by S.cerevisiae, H.uvarum and K.marxianus was higher in the supplemented fermentations, compared to the unsupplemented ones. In T.delbrueckii, the initial volatile compound concentrations remained unchanged, or decreased for some compounds, with nitrogen supplementation.
The initial acetic acid and vanillin concentrations decreased with all strains tested and nitrogen supplementation. Furthermore,
the concentration of higher alcohols increased with S.cerevisiae and H.uvarum in the NH4Cl-supplemented fermentations, but they decreased with T.delbrueckii and K.marxianus. In conclusion, the addition of an inorganic nitrogen source promotes microorganism metabolism, increases biomass formation
and benefits the fermentation process.
Content Type Journal Article
Category Original Paper
Pages 1-7
DOI 10.1007/s00217-012-1729-4
Authors
O. Miriam Rutiaga-Quiñones, Departamento de IngenierÃas QuÃmica y BioquÃmica, Instituto Tecnológico de Durango, Durango, Mexico
Érica Córdova, Departamento de IngenierÃas QuÃmica y BioquÃmica, Instituto Tecnológico de Durango, Durango, Mexico
MarÃa A. Martell-Nevárez, Departamento de IngenierÃas QuÃmica y BioquÃmica, Instituto Tecnológico de Durango, Durango, Mexico
Jóse M. Guillamón, Departamento de BiotecnologÃa de los Alimentos, Instituto de AgroquÃmica y TecnologÃa de los Alimentos (CSIC), Valencia, Spain
Nicolas Rozès, Departamento de Bioquimica y Biotecnologia, Facultad de Enologia, Universitat Rovira i Virgili, Tarragona, Spain
Jesús Páez, Departamento de IngenierÃas QuÃmica y BioquÃmica, Instituto Tecnológico de Durango, Durango, Mexico
In the past, the transgenic soybean Roundup Ready was the predominantly cultivated transgenic soybean. With the announcement
of Monsanto Corp. that this trait will be replaced by Mon89788 and the release of other company’s transgenic soy crops, this
unique status of one trait has ended. Therefore, a multiplex quantitative real-time PCR system was developed and characterized
for three additional transgenic traits Mon89788, A2704-12 and A5547-127. It showed amplification efficiency, correlation and
sensitivity similar to the single PCR systems applied therein. This system allows relative multiplex quantification and/or
delta–delta Ct method and therefore an efficient control of products during production, trade and sale.
The production of fructooligosaccharides (FOS) and β-fructofuranosidase (FFase) by immobilized cells of Penicillium expansum was evaluated. In an initial stage, different low-cost materials including synthetic fiber, polyurethane foam, stainless
steel sponge, loofah sponge, and cork oak were tested as carrier for the fungus immobilization. Additionally, the influence of the inoculum age (1 or
3 weeks) on cells immobilization, FOS and FFase production was also verified. Synthetic fiber and polyurethane foam were the
best materials for P. expansum immobilization (2.21 and 1.98 g/g carrier, respectively) and FOS production (120.3 and 104.8 g/l), and gave also high results
of FFase activity (23.01 and 32.42 U/ml). Then, the production of FOS and FFase by repeated batch fermentation with P. expansum immobilized on synthetic fiber was studied, aiming to improve the batch fermentation results. The results obtained in this
stage were very promising with FOS yields of 87, 72, and 44 %, in the 3 initial cycles (60 h), respectively; the FFase activity
was constant throughout the process (6 cycles, 96 h). Repeated batch fermentation with immobilized cells of P. expansum was found as being a technology with great potential for FOS and FFase production on industrial scale.
Content Type Journal Article
Category Original Paper
Pages 1-10
DOI 10.1007/s00217-012-1728-5
Authors
Solange I. Mussatto, Institute for Biotechnology and Bioengineering (IBB), Centre of Biological Engineering, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal
Margarida B. Prata, Institute for Biotechnology and Bioengineering (IBB), Centre of Biological Engineering, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal
LÃgia R. Rodrigues, Institute for Biotechnology and Bioengineering (IBB), Centre of Biological Engineering, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal
Aside from bacteria, yeasts and moulds, enzymes from animal, vegetal and microbial sources are increasingly utilized for milk
fermentation providing a broad spectrum of innovative product conceptions. In order to alter texture and flavour or to improve
the nutritional value of milk-based products from different animal milks, microbial and enzymatic fermentation procedures
are traditionally established worldwide. To date, genomic and proteomic approaches enable new selection strategies for precise
enzymes for modern product applications. Hereby, generating beneficial health ingredients from milk is a main aspect. New
insights into the biochemical mechanisms of enzymatic digestion and genetic engineering lead to enzymes with exact defined
functions for explicit ripening flavour development or the improvement of texture of fermented milk products. The ability
to synthesize complex exo-polysaccharides or to release bioactive peptides by accurate proteolytic activities of enzymes or
to enzymatically cross-link the protein matrix in order to modify the texture characteristics of fermented milk products is
a raising facet, especially for specific pharma- or nutraceutical applications. This review aimed at discussing the recent
research activities on milk fermentative enzymes, with focus on the broad spectrum of enzyme origins and current aspects of
genetic engineering. New approaches on proteolytic, lipolytic, glycolytic as well as milk clotting and protein cross-linking
enzymatic activities are examined and associated with possible product applications. From technical prospective, advantages
and disadvantages of immobilized enzymes within milk fermentation processes are critically discussed.
Content Type Journal Article
Category Review Paper
Pages 1-12
DOI 10.1007/s00217-012-1733-8
Authors
Christopher Beermann, Faculty of Food Technology, University of Applied Science Fulda, Marquardstrasse 35, Fulda, 36039 Germany
Julia Hartung, Faculty of Food Technology, University of Applied Science Fulda, Marquardstrasse 35, Fulda, 36039 Germany
Methamidophos (MAP) is a highly efficient and broad-spectrum organophosphate pesticide. In this study, a rapid method for
detecting MAP in vegetables using surface enhanced Raman scattering (SERS) spectroscopy has been established. Density functional
theory calculations were performed with Gaussian 03 at RB3LYP level and with the 6-311G (d) basis set. SERS, normal and theoretical
Raman spectroscopy were compared to investigate the mechanism of Raman scattering enhancement. The SERS signal of MAP was
improved in alkaline conditions with optimum scattering efficiency at pH of 13.46. Furthermore, MAP detection in vegetables
by SERS method had a good linear relationship between 0.01 and 1,000 μg/mL. The concentration of MAP in vegetables was detected
and chosen for recovery test with three levels: 4, 8, and 15 μg/mL. The results of three level tests were 86.7–96.6 % and
their relative standard deviations were between 1.2 and 2.5 %, which shows the good repeatability of this method.
Content Type Journal Article
Category Original Paper
Pages 1091-1098
DOI 10.1007/s00217-012-1724-9
Authors
Yunfei Xie, State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122 Jiangsu, China
Godelieve Mukamurezi, State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122 Jiangsu, China
Yingying Sun, State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122 Jiangsu, China
Heya Wang, State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122 Jiangsu, China
He Qian, State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122 Jiangsu, China
Weirong Yao, State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122 Jiangsu, China
Food-borne illness outbreaks are increasingly associated with fresh produce. Their high prevalence may reflect the lack of
methods to effectively remove pathogenic bacteria from the surface of fruits and vegetables. This study evaluated the effect
of antimicrobial gallotannins on attachment, growth, and survival of food-borne pathogens on green leafy vegetables. Spinach
leaves and interior leaves of lettuce harboring high and low cell counts of background microbiota, respectively, were washed
with tap water with and without added gallotannins. To account for the variability among organisms, green leafy vegetables
were inoculated with strain cocktails of Escherichia coli O157:H7 and Listeria monocytogenes. Cell counts of L. monocytogenes were significantly reduced by the gallotannin treatment. Lower cell counts after storage for 8 days at 4 °C demonstrated
antimicrobial effects of gallotannins retained on the surface of green leafy vegetables. Gallotannin treatments with 1 g/L
did not inhibit E. coli O157:H7 but hindered their attachment to filter paper by up to 94 %. The addition of gallotannin-containing extracts from
mango (Mangifera indica L.) kernels to the washing water did neither alter color nor texture of bagged fresh-cut products. In conclusion, gallotannin
treatment significantly reduced surface contamination of green leafy vegetables with L. monocytogenes and reduced the attachment of cells of E. coli O157:H7.
Content Type Journal Article
Category Original Paper
Pages 1081-1090
DOI 10.1007/s00217-012-1727-6
Authors
Christina Engels, Department of Agricultural, Food and Nutritional Science, University of Alberta, 4-10 Ag/For Centre, Edmonton, AB T6G 2P5, Canada
Agnes Weiss, Institute of Food Science and Biotechnology, Food Microbiology, Hohenheim University, Garbenstrasse 28, 70599 Stuttgart, Germany
Reinhold Carle, Institute of Food Science and Biotechnology, Plant Foodstuff Technology, Hohenheim University, Garbenstrasse 25, 70599 Stuttgart, Germany
Herbert Schmidt, Institute of Food Science and Biotechnology, Food Microbiology, Hohenheim University, Garbenstrasse 28, 70599 Stuttgart, Germany
Andreas Schieber, Department of Agricultural, Food and Nutritional Science, University of Alberta, 4-10 Ag/For Centre, Edmonton, AB T6G 2P5, Canada
Michael G. Gänzle, Department of Agricultural, Food and Nutritional Science, University of Alberta, 4-10 Ag/For Centre, Edmonton, AB T6G 2P5, Canada
There is a growing interest in the use of ultrasound (US) as an alternative to conventional processes. Although US has previously
been applied as a pretreatment of fruits and vegetables, no investigation has been done on the usefulness of US for carrot
blanching, paying special attention to its effect on enzyme inactivation and leaching losses. In the present paper, the influence
of US (in bath and with probe) on peroxidase (POD) and pectinmethylesterase (PME) inactivation and on the loss of total soluble
solids and carbohydrates by leaching has been evaluated. Results of this preliminary study have also been compared with those
obtained after conventional (hot water and steam) blanching of carrots. The highest enzyme inactivation was obtained with
the conventional treatments performed at high temperatures and with the US probe treatments with heat generation. Carrots
blanched by US probe for 10 min at a temperature up to 60 °C showed characteristics similar to those conventionally treated
at 60 °C for 40 min. Although the efficiency of US was limited for total inactivation of POD and PME, this treatment resulted
to be advantageous in terms of time for blanching at mild temperatures. US probe treatments could also be considered as an
advantageous alternative to low-temperature long-time (LTLT) conventional treatments for those applications in which partial
inactivation of PME is required for the better preservation of carrot structure.
Content Type Journal Article
Category Original Paper
Pages 1071-1079
DOI 10.1007/s00217-012-1726-7
Authors
Juliana Gamboa-Santos, Instituto de Investigación en Ciencias de la Alimentación (CIAL), CSIC-UAM, Nicolás Cabrera, 9, Campus de la Universidad Autónoma de Madrid, 28049 Madrid, Spain
Antonia Montilla, Instituto de Investigación en Ciencias de la Alimentación (CIAL), CSIC-UAM, Nicolás Cabrera, 9, Campus de la Universidad Autónoma de Madrid, 28049 Madrid, Spain
Ana C. Soria, Instituto de QuÃmica Orgánica General (IQOG), CSIC, Juan de la Cierva, 3, 28006 Madrid, Spain
Mar Villamiel, Instituto de Investigación en Ciencias de la Alimentación (CIAL), CSIC-UAM, Nicolás Cabrera, 9, Campus de la Universidad Autónoma de Madrid, 28049 Madrid, Spain
The present study was carried out to evaluate the effect of environmental factors (air and UV-C irradiation) on various common
fruits juices (lemon, orange, papaya and grape). Total phenolics, total ascorbic acid (AA) content and antioxidant capability
were determined in atmospheric air oxidation on fresh fruit juices, and the effect of UV-C irradiation on AA was investigated
in both fresh fruit juices and commercial AA using RP-HPLC. The total phenolics content was found to be 92.46 ± 1.5, 41.53 ± 2.1,
138.56 ± 2.3 and 110.54 ± 3.9 mg/100 ml of lemon, orange, papaya and grape juices, respectively. DPPH radical–scavenging activity
of the fresh juices was 94.53 ± 3.1, 82.36 ± 2.2, 94.65 ± 3.5 and 90.74 ± 2.6 percentage, whereas the 1-day-old fruit juices
showed reduced scavenging activity when compared to fresh juices. Total phenolic (TP) and DPPH-scavenging activity were significantly
decreased in the mean at P < 0.05 level. Ascorbic acid (vitamin C) content of fresh fruit juices was determined through RP-HPLC; fruit juices that were
kept in open container for 24 hrs and that were treated with UV irradiation have shown a decrease in AA content, when compared
with control fresh juice samples. AA degradation increased with high significant differences at P < 0.001 level, with the increase in oxidation time in atmospheric air and UV-C radiation.
Content Type Journal Article
Category Original Paper
Pages 1063-1070
DOI 10.1007/s00217-012-1711-1
Authors
A. Rameshkumar, Department of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli, 620 024 Tamilnadu, India
T. Sivasudha, Department of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli, 620 024 Tamilnadu, India
R. Jeyadevi, Department of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli, 620 024 Tamilnadu, India
D. Arul Ananth, Department of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli, 620 024 Tamilnadu, India
G. Pradeepha, Department of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli, 620 024 Tamilnadu, India
A loop-mediated isothermal amplification (LAMP) assay was developed and validated for the specific detection of Salmonella in food. The four primers required for LAMP were designed using a conserved region in the histidine transport protein-coding
region of Salmonella. Seventy-nine reference strains of 72 Salmonella serovars and 23 non-Salmonella strains were detected by LAMP. The detection limit of this assay is 16 CFU per reaction in pure culture, up to tenfold more
sensitive than that of the PCR assay with the same target gene. When applied in raw food samples, a sample pretreatment protocol
was performed that included a pre-enrichment step in 0.1 % buffered peptone water, followed by a selective enrichment in Rappaport–Vassiliadis
medium. Using this method, 200 assorted food samples were investigated for Salmonella, including fresh pork, whole chickens, and green vegetables. The sensitivity of LAMP for the detection of Salmonella in food samples was 93.55 %, versus 87.10 % that tested positive using conventional PCR. The results from this study showed
that the HisJ-based LAMP is an effective method for the detection of foodborne Salmonella.
Content Type Journal Article
Category Original Paper
Pages 1055-1062
DOI 10.1007/s00217-012-1725-8
Authors
Lei Zhang, Jiangsu Key Laboratory of Zoonosis, Yangzhou University, 12 East Wenhui Road, Yangzhou, Jiangsu 225009, People’s Republic of China
Zhi-ming Pan, Jiangsu Key Laboratory of Zoonosis, Yangzhou University, 12 East Wenhui Road, Yangzhou, Jiangsu 225009, People’s Republic of China
Shi-zhong Geng, Jiangsu Key Laboratory of Zoonosis, Yangzhou University, 12 East Wenhui Road, Yangzhou, Jiangsu 225009, People’s Republic of China
Xiang Chen, Jiangsu Key Laboratory of Zoonosis, Yangzhou University, 12 East Wenhui Road, Yangzhou, Jiangsu 225009, People’s Republic of China
Zhong-Yi Liu, Jiangsu Key Laboratory of Zoonosis, Yangzhou University, 12 East Wenhui Road, Yangzhou, Jiangsu 225009, People’s Republic of China
Fei Zhao, Jiangsu Key Laboratory of Zoonosis, Yangzhou University, 12 East Wenhui Road, Yangzhou, Jiangsu 225009, People’s Republic of China
Xin-an Jiao, Jiangsu Key Laboratory of Zoonosis, Yangzhou University, 12 East Wenhui Road, Yangzhou, Jiangsu 225009, People’s Republic of China
From ethyl acetate fraction of olive pomace, solid residue from olive oil extraction, a new compound was isolated and purified
through solid-phase extraction using silica Cartridge column chromatography. The structure of the new compound was established
as a deoxyloganic acid lauryl ester by spectroscopic data including one- and two-dimensional NMR, electrospray ionization
mass spectrometry, infrared analysis and UV spectra. The antioxidant activity of the purified compound was evaluated by measuring
the radical-scavenging effect on 2,2-diphenyl-1-picrylhydrazyl and by using the ferric reducing antioxidant power assays.
The pure compound has not been previously identified in the genus Olea and could be used as for studying the biosynthetic pathway of oleuropein aglycon.
To enhance the yield and productivity of milk-clotting enzyme (MCE) by Bacillus amyloliquefaciens, a two-stage oxygen supply control strategy was proposed and successfully applied in the MCE fermentation. During the first
16 h, KLa was controlled at 72.2 h−1 to obtain high cell growth rate (v) and MCE activity (MCA) productivity (rMCA). Subsequently, KLa was controlled at 33.9 h−1 to maintain high specific MCA productivity (qMCA). Using this strategy, MCA peaked at 36 h with the MCA of 6,590.41 SU ml−1, which was 18 h earlier than other investigated processes. The concept and results described represent the basis of an industrial
scale-up process to achieve high MCE yield, MCA productivity and MCA/proteolytic activity.
Content Type Journal Article
Category Original Paper
Pages 1043-1048
DOI 10.1007/s00217-012-1723-x
Authors
Zhongyang Ding, National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi, People’s Republic of China
Lianzhong Ai, State Key Laboratory of Dairy Biotechnology, Technology Center of Bright Dairy and Food Co. Ltd., 1518 West Jiangchang Road, Shanghai, 200436 People’s Republic of China
Anran Ouyang, National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi, People’s Republic of China
Mingliang Ding, National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi, People’s Republic of China
Wangfei Wang, National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi, People’s Republic of China
Boda Wang, National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi, People’s Republic of China
Shuangping Liu, National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi, People’s Republic of China
Zhenghua Gu, National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi, People’s Republic of China
Liang Zhang, National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi, People’s Republic of China
Guiyang Shi, National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi, People’s Republic of China
In this research, a rapid immunosensor targeting aflatoxigenic Aspergilli was developed based on impedimetric electrochemical
technology, involving the use of polyclonal antibody specific to extracellular antigen produced by Aspergillus parasiticus GIM 3.395. This sensor was fabricated by immobilization of antibody on gold nanoparticle/l-cysteine-coated electrode. All results showed that the immunosensor exhibited high sensitivity with a detection limit of
18 colony-forming unit (cfu/mL) (S/N = 3) and required simple sample treatment free of the pre-enrichment step. Moreover,
the whole detection time was only 30 min and more rapid as compared to conventional culture-based techniques or PCR methods.
Other 16 strains of Aspergilli were also used to determine the immunosensor specificity, and the results showed that the immunosensor
had high specificity. The immunosensor exhibited a long-term stability, and high reproducibility of the signal could be obtained
up to 100 times with an R.S.D. of 2.5 %. To assess the applicability of the immunosensor for pathogen detection in food process,
soybean paste of naturally fermentation with koji-making process was analyzed. The average recovery rate was ranged from 81.5
to 113.5 %. It was shown that the immunosensor provided a fast, sensitive and specific detection of aflatoxigenic Aspergilli
and could potentially be used as a real-time and early diagnosis tool for aflatoxin B1 in foods.
Content Type Journal Article
Category Original Paper
Pages 1013-1021
DOI 10.1007/s00217-012-1716-9
Authors
Xiulan Sun, State Key Laboratory of Food Science and Technology, School of Food Science of Jiangnan University, Wuxi, 214122 Jiangsu, China
Li Yan, State Key Laboratory of Food Science and Technology, School of Food Science of Jiangnan University, Wuxi, 214122 Jiangsu, China
Yanjie Tang, Department of Food Science of Purdue University, West Lafayette, IN 47907, USA
Yinzhi Zhang, State Key Laboratory of Food Science and Technology, School of Food Science of Jiangnan University, Wuxi, 214122 Jiangsu, China
To get a more comprehensive knowledge of oil contents and fatty acid pattern, seed oils from various Rosaceous plants belonging
to the subfamilies Maloideae and Rosoideae, respectively, were investigated. For this purpose, isolated seeds of 18 dessert
and cider apple (Malus domestica BORKH.) cultivars of different provenances, pear (Pyrus communis L.), rose hip (Rosa canina L.), quince (Cydonia oblonga Mill.), and red chokeberry (Aronia arbutifolia L.) were analyzed for their oil content and fatty acid composition. Oil contents varied significantly, not only among the
different genera, but also among cultivars of one species, ranging from 0.8 to 29.4 g/100 g dry matter. Qualitatively, the
fatty acid profiles of the investigated seed oils showed good agreement in all representatives of the Rosaceae. Their triacylglycerols
were uniformly composed of linoleic, oleic, palmitic, stearic, palmitoleic, α-linolenic, arachidic, gondoic, and behenic acids.
Quantitation of individual fatty acids revealed the oils to be rich in mono- and diunsaturated oleic acid and linoleic acid,
ranging from 15.1 to 33.3 g/100 g and from 32.5 to 49.7 g/100 g, respectively. As expected, contents of saturated fatty acids
were 6–10 times lower. Moreover, apple cultivars showed pronounced differences in yields, numbers, and weights of their seeds.
As demonstrated by the data obtained from this study, seeds resulting from the processing of apple, pear, quince, chokeberry
(Maloideae), and rose hip (Rosoideae) into juices, jellies, and jams may serve as a promising source for the recovery of nutritionally
valuable edible oils.
Content Type Journal Article
Category Original Paper
Pages 1033-1041
DOI 10.1007/s00217-012-1709-8
Authors
Matthias Fromm, Institute of Food Science and Biotechnology, Chair Plant Foodstuff Technology, Hohenheim University, Garbenstrasse 25, 70599 Stuttgart, Germany
Sandra Bayha, Institute of Food Science and Biotechnology, Chair Plant Foodstuff Technology, Hohenheim University, Garbenstrasse 25, 70599 Stuttgart, Germany
Reinhold Carle, Institute of Food Science and Biotechnology, Chair Plant Foodstuff Technology, Hohenheim University, Garbenstrasse 25, 70599 Stuttgart, Germany
Dietmar R. Kammerer, Institute of Food Science and Biotechnology, Chair Plant Foodstuff Technology, Hohenheim University, Garbenstrasse 25, 70599 Stuttgart, Germany
To investigate the possible mechanism of color degradation of green prickleyashes (Zanthoxylum schinifolium Zucc.) in slow drying, changes in their peel colors, enzyme activities, content of chlorophylls (Chls) and derivatives were evaluated.
The results showed the peel color changed from brilliant green to black-brown and Chls underwent a rapid degradation. Enzyme
activities changed as follows: chlorophyllase activity decreased; chlorophyll-degrading peroxidase (Chl-POD) activity as well
as pheophorbidase (Pheidase) exhibited a biphase trend displaying an inverted “V†phase, and the increase in Chl-POD resulted
in the accumulation of C132-hydroxy-chlorophyll a. Based on the study of enzyme activities and Chl degradation, conclusions were drawn that Chl-POD and
Pheidase were considered as the key enzymes to promote chlorophyll breakdown. Compared with slow drying, fast drying could
inhibit the two key enzyme activities and blockade the chlorophyll-degrading pathway, which was proposed to process green
prickleyashes.
Content Type Journal Article
Category Original Paper
Pages 1023-1031
DOI 10.1007/s00217-012-1718-7
Authors
Kewei Chen, College of Food Science, Southwest University, Chongqing, 400715 China
Fusheng Zhang, College of Food Science, Southwest University, Chongqing, 400715 China
Jianquan Kan, College of Food Science, Southwest University, Chongqing, 400715 China
Cultivation of soybean sprouts in abiotic stress conditions, resulted from the presence of 5–25 mM FeSO4 in the culture media, causes a strong overexpression of ferritin. Accumulation of ferritin iron in sprouted seeds germinated
in the 20 mM solution of FeSO4 was 67 times higher than in sprouts germinated in distilled water. The cultivation conditions also influence on another antioxidant
content—mainly β-carotene content, which increased 28 times (in sprouts cultured in 10 mM FeSO4 solution) in comparison to the content in dry seeds. Obtained in stress conditions sprouted seeds contain less tocochromanoles
than raw seeds. However, their total tocochromanol content was higher than in sprouted seeds cultured in distilled water in
every examined concentration of Fe2+. A total antioxidant activity is increased only during culturing in 0–10 mM media, and it is positively correlated to the
total phenolic compounds content (r = 0.8498). We concluded that germination in high abiotic stress also causes the increase in different antioxidants content,
not only in ferritin, which is directly involved in the process of iron detoxification.
Content Type Journal Article
Category Original Paper
Pages 1005-1012
DOI 10.1007/s00217-012-1706-y
Authors
Magdalena Zielińska-Dawidziak, Department of Biochemistry and Food Analysis, Poznan University of Life Sciences, Mazowiecka 48, 60-623 Poznan, Poland
Aleksander Siger, Department of Biochemistry and Food Analysis, Poznan University of Life Sciences, Mazowiecka 48, 60-623 Poznan, Poland
This paper investigates the possibility for iron fortification of food using protein gel particles in which iron is entrapped
using cold-set gelation. The aim is to optimize the iron encapsulation efficiency of whey protein by giving the whey protein
different heat treatment prior to gelation with iron. The effect of the heat treatment conditions (mild-intermediate-severe)
on the iron-induced cold-set gelation process was studied to optimize the gel strength in relation to the iron concentration.
Rheology was used to study the protein gel formation, and the stability of the gel particles and iron encapsulation efficiency
was determined by measuring the protein and iron content at different pH. Both the iron concentration and the heat treatment
conditions appear to affect the gel formation process and gel strength of the iron-induced cold-set gels. With the protein
gel particles being stable at a broad pH range, the release of iron from the particles was studied as a function of time.
The low release of iron at neutral pH indicated good encapsulation efficiency and capability of whey protein to keep iron
bound. At low pH the release of iron increased, as is desired for bio-accessibility. In addition to differences in gel strength,
the most relevant result caused by the pre-treatment of the whey protein is revealed in the amount of iron that can be entrapped
per protein. It is shown that the amount of iron can be increased going from mild to severe heat treatment conditions. This
suggests that the concept of using whey protein particles with iron can effectively be used to fortify food products with
iron for human consumption.
Content Type Journal Article
Category Original Paper
Pages 995-1003
DOI 10.1007/s00217-012-1717-8
Authors
A. H. Martin, TNO, Functional Ingredients, P.O. Box 360, 3700 AJ Zeist, The Netherlands
G. A. H. de Jong, TNO, Functional Ingredients, P.O. Box 360, 3700 AJ Zeist, The Netherlands
To standardize the rice-specific PCR detection methods, five previously reported rice (Oryza sativa) taxon-specific genes were compared and evaluated. The investigated genes included the rice root-specific gene (gos9), the ppiphosphofructokinase gene (ppi-PPF), the phospholipase D gene (PLD), the starch branching enzyme gene (RBE4) and the sucrose phosphate synthase gene (SPS). Sequencing analyses revealed that among the tested rice cultivars, single-nucleotide polymorphisms (SNPs) existed in the
gos9, PLD, ppi-PPF and SPS amplicons, though no statistically significant effect on their Ct values was found. The ppi-PPF and PLD systems were found to produce amplicons in non-rice species, such as sugarcane and broomcorn. The quantitative real-time
PCR results revealed that this cross-reaction led to an underestimate of the GM (genetically modified) rice content. With
the exception of the aforementioned shortcomings, these five endogenous reference genes all have acceptable amplification
efficiencies, which ranged from 98 to 108 %, and high sensitivity within the limit of detection (LOD) values, which ranged
from 5 to 10 copies of the haploid genome. In estimating the GM content in blinded rice samples, these five systems produce
relatively accurate quantitative results with deviations less than 15 %, but the RBE4 system produced the most accurate quantitative results. Therefore, we have determined that the RBE4 gene is the most suitable rice reference gene, and the gos9 and SPS genes can also be used as rice reference genes because they have good commutability with the RBE4 gene. Care should be taken when interpreting results based on the PLD and ppi-PPF genes owing to their cross-reaction with other species.
Content Type Journal Article
Category Original Paper
Pages 981-993
DOI 10.1007/s00217-012-1707-x
Authors
Li Zhang, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences; Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, No.2 Xudong Second Road, Wuhan, 430062 People’s Republic of China
Yinglong Cao, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences; Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, No.2 Xudong Second Road, Wuhan, 430062 People’s Republic of China
Xin Liu, Development Center of Science and Technology, Ministry of Agriculture, Beijing, 100122 People’s Republic of China
Gang Wu, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences; Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, No.2 Xudong Second Road, Wuhan, 430062 People’s Republic of China
Yuhua Wu, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences; Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, No.2 Xudong Second Road, Wuhan, 430062 People’s Republic of China
Changming Lu, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences; Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture, No.2 Xudong Second Road, Wuhan, 430062 People’s Republic of China
Combined effects of concentration of lactose (5 g/L), NaCl (20 g/L) and aero/anaerobiosis on production of tyramine by Enterococcus durans CCDM 53 were subjected to a study. The influence of the above factors and temperature of cultivation (10 ± 1 °C) was monitored
under conditions applied in real technological processes of cheese production; the enterococci act as non-starter lactic acid
bacteria. Production of tyramine by E. durans CCDM 53 was mainly influenced by both concentration of NaCl in cultivation medium and presence/absence of oxygen in the environment.
The highest production of tyramine occurred during cultivation under anaerobic conditions in the presence of the highest (20 g/L)
applied concentration of NaCl and lactose (5 g/L). In the media with equal concentrations of NaCl and lactose, the concentrations
of tyramine grew higher under anaerobic conditions than in aerobic environment. Regarding cultivation media with various levels
of NaCl and lactose, higher production of tyramine was always found in the anaerobic environment.
Content Type Journal Article
Category Original Paper
Pages 973-979
DOI 10.1007/s00217-012-1714-y
Authors
Leona Buňková, Department of Fat, Tenside and Cosmetics Technology, Faculty of Technology, Tomas Bata University in Zlin, Nam. T.G.Masaryka 275, 762 72 Zlin, Czech Republic
František Buňka, Department of Food Technology and Microbiology, Faculty of Technology, Tomas Bata University in Zlin, Nam. T.G.Masaryka 275, 762 72 Zlin, Czech Republic
VladimÃr Dráb, Dairy Research Institute, Ke Dvoru 12a, 160 00 Prague, Czech Republic
Stanislav KráÄmar, Department of Food Analysis and Chemistry, Faculty of Technology, Tomas Bata University in Zlin, Nam. T.G.Masaryka 275, 762 72 Zlin, Czech Republic
Vlastimil Kubáň, Department of Food Technology and Microbiology, Faculty of Technology, Tomas Bata University in Zlin, Nam. T.G.Masaryka 275, 762 72 Zlin, Czech Republic
Benzo (1, 2, 3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH) is a novel synthetic elicitor capable of inducing disease
resistance in many plants. Fruits were dipped in BTH at 100 mg/L for 10 min, and then stored at room temperature (22 ± 2 °C,
relative humidity 55–60 %). The results showed that BTH significantly (P < 0.05) reduced the lesion area of fruits inoculated with Trichothecium roseum and the natural disease incidence of fruits during storage at room temperature. The treatment effectively maintained cell
membrane integrity and decreased the production of lipid peroxidation and malondialdehyde. BTH treatment markedly enhanced
the accumulation of hydrogen peroxide, (H2O2) while decreased the rate of superoxide anion (O2·−) production. Furthermore, BTH observably increased the activities of NADPH oxidase (NOX, EC1.6.3.1), superoxide dismutase
(SOD, EC1.15.1.1), peroxidase (POD, EC1.11.1.7), ascorbate peroxidase (APX, EC1.11.1.11), and glutathione reductase (GR, EC1.6.4.2),
while inhibited the catalase (CAT, EC1.11.1.6) activity. These results indicated that BTH treatment increased the disease
resistance of muskmelon fruits by enhancing their antioxidant system activity after harvest, and suggested that postharvest
treatment with BTH could be promising in reducing decay and reducing or/and substituting chemical fungicides to control postharvest
diseases in fruits.
Content Type Journal Article
Category Original Paper
Pages 963-971
DOI 10.1007/s00217-012-1715-x
Authors
Yalin Ren, College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, 730070 China
Yunfei Wang, College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, 730070 China
Yang Bi, College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, 730070 China
Yonghong Ge, College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, 730070 China
Yi Wang, College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, 730070 China
Cunfei Fan, College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, 730070 China
Daqiang Li, College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, 730070 China
Huiwen Deng, College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, 730070 China
The phytanic acid content in milk correlates with the amount of green items in the cows’ feed. For this reason, the four-fold
methyl-branched fatty acid has been suggested as a potential marker for the authentication of organic milk. In this study,
we attempted to provide further support for this idea by studying the progression of the phytanic acid level and diastereomer
ratio in milk fat by transition of the diets from high proportions of concentrate (typical “conventional†feed) to hay (typical
“organic†feed in winter) and back to “conventional†feed. Milk samples taken from three cows were analyzed on both the phytanic
acid concentration and diastereomer distribution. The cows were initially fed with “conventional†feed (ground feed with high
portions (30–45 %) of concentrate), then the feed was changed within 1 week to 100 % hay (“organic†feed), and after ~6 weeks,
the feed of two cows was changed back to the initial feed with concentrate (phase Cb). During the “conventional†feeding at the beginning of the experiment, the phytanic acid concentration was low (100–130 mg/100 g
milk fat). When the feed was changed to hay (“organic†feed), the phytanic acid concentration immediately increased to a stable
level of about 160 mg/100 g lipids. Changing back the feed to “conventional†feed, the phytanic acid concentration dropped
immediately back below the value measured in the initial phase. Likewise, the SRR/RRR-diastereomer distribution of phytanic
acid in the milk was an excellent indicator for the changes in the cows’ feed. While the SRR/RRR-diastereomer ratio was >1.5
during “conventional†feeding, it immediately decreased to equal amounts of both diastereomers when hay was supplied as feed.
Abandonment of concentrate in conventional feeding increased the phytanic acid content but the SRR-diastereomer was still
dominant and thus the SRR/RRR-diastereomer ratio was different to organic milk. Our results indicate that both parameters,
i.e., the phytanic acid content and SRR/RRR-diastereomer ratio need to be measured for authentication of organic milk.
Content Type Journal Article
Category Original Paper
Pages 955-962
DOI 10.1007/s00217-012-1710-2
Authors
Markus Schröder, Institute of Food Chemistry (170b), University of Hohenheim, Garbenstr. 28, 70593 Stuttgart, Germany
Nina Larissa Lutz, Institute of Food Chemistry (170b), University of Hohenheim, Garbenstr. 28, 70593 Stuttgart, Germany
Ernest Chick Tangwan, Institute of Food Chemistry (170b), University of Hohenheim, Garbenstr. 28, 70593 Stuttgart, Germany
Ensieh Hajazimi, Institute of Food Chemistry (170b), University of Hohenheim, Garbenstr. 28, 70593 Stuttgart, Germany
Walter Vetter, Institute of Food Chemistry (170b), University of Hohenheim, Garbenstr. 28, 70593 Stuttgart, Germany
In this research, a protease from the compositae (Scorzonera hispanica L.) was extracted and purified through (NH4)2SO4 precipitation, CM-Sephadex and Sephacryl S200. At the end of purification by gel filtration on a Sephacryl S-200 column,
87.11-fold purification was achieved. It was shown that purified enzyme was homogeneous in terms of SDS-PAGE with molecular
mass estimate of 30 kDa. The enzyme named compositain depicted an optimal pH of 8.0 and was stable at pH 7.0–9.0, and its
optimal temperature was at 50 °C. While Tween 80 (0.2 %) was activated to the purified protease enzyme, it was partially inhibited
by 5 mM concentration of some metal salts and EDTA, PMSF, dithiothreitol, H2O2 and β-mercaptoethanol. The enzyme activity was stable even in the presence of detergents and organic solvents. In addition,
it was investigated whether the purified and characterized protease enzyme would cause to congeal milk. As a result, it was
determined that the compositain could congeal milk and it would be used for cheese production. The compositain had potential
application in food processing.
Content Type Journal Article
Category Original Paper
Pages 945-953
DOI 10.1007/s00217-012-1719-6
Authors
Hayrunnisa Nadaroglu, Department of Food Technology, Erzurum Vocational School, Ataturk University, 25240 Erzurum, Turkey
Nazan Demır, Department of Chemistry, Faculty of Science, Mugla University, Mugla, Turkey
The production of heat-induced gels from raw materials with poor gelling ability remains a technical challenge, for which
new solutions have been proposed. The addition to the gel batters of a cross-linking chemical agent, such as 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide
(EDC), may present a valuable tool for the improvement of gelling. Accordingly, a response surface methodology was used to
optimize the conditions of EDC application, the EDC concentration (0.0–0.5 %, w/w) and the batters’ pH (4.5–7.5). Results
showed that textural, colour, and water-binding properties of heat-induced hake gels were extremely sensitive to EDC content
and pH. It was possible to find an optimal EDC level-pH binary common to the various studied parameters, a pH between 4.0
and 5.0 and an EDC concentration of 0.5 %, w/w. Moreover, this experimental work proved to be feasible the achievement of
gel products of acceptable textural quality from frozen hake through EDC incorporation in optimal conditions.
Content Type Journal Article
Category Original Paper
Pages 935-943
DOI 10.1007/s00217-012-1713-z
Authors
Carlos Cardoso, Instituto Nacional dos Recursos Biológicos (INRB, I.P./L-IPIMAR), Avenida de BrasÃlia, 1449-006 Lisbon, Portugal
Bernardo Ribeiro, Instituto Nacional dos Recursos Biológicos (INRB, I.P./L-IPIMAR), Avenida de BrasÃlia, 1449-006 Lisbon, Portugal
The partial nucleotide sequences encoding elongation factor Tu (tuf gene), 60-kDa heat shock protein (hsp60 gene) and phenylalanyl-tRNA synthase (pheS gene) were determined to assess the suitability as phylogenetic markers for discriminating the closely related species in
Lactobacillusacidophilus group, L. casei group and L. plantarum group. A total of 234 lactobacilli were chosen from traditional fermented dairy products that were not exactly assigned to
species based on biochemical tests and 16S rRNA gene sequences. The sequencing of partial tuf, hsp60 and pheS gene of all strains was performed, and then, the phylogenetic trees were constructed by neighbor-joining method. Phylogenetic
tree revealed three genes provided better resolution of each Lactobacillus species than 16S rDNA, and all of strains were clearly identified as L. casei (63 strains), L. plantarum (58 strains) and L. helveticus (113 strains) by comparison of sequences with the type strains. From our results, the partial sequences of three genes had
a higher discriminatory power than 16S rRNA gene sequences and were an alternative molecular tool for the taxonomical analysis
of L. casei group, L. plantarum group and L. acidophilus group.
Content Type Journal Article
Category Original Paper
Pages 927-934
DOI 10.1007/s00217-012-1712-0
Authors
Jie Yu, Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Huhhot, Inner Mongolia, 010018 People’s Republic of China
Zhihong Sun, Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Huhhot, Inner Mongolia, 010018 People’s Republic of China
Wenjun Liu, Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Huhhot, Inner Mongolia, 010018 People’s Republic of China
Qiuhua Bao, Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Huhhot, Inner Mongolia, 010018 People’s Republic of China
Jiachao Zhang, Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Huhhot, Inner Mongolia, 010018 People’s Republic of China
Heping Zhang, Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Huhhot, Inner Mongolia, 010018 People’s Republic of China
Oligopeptides were prepared from the guts of sea cucumber Stichopus japonicus by autolysis method. Optimum autolysis conditions for preparing oligopeptides from the guts of sea cucumber were determined
by response surface methodology using a central composite rotatable design. The effects of two independent variables, namely
temperature and pH, on the response of trichloroacetic acid-soluble oligopeptides (mg/g on dry basis) were investigated. Regression
analysis indicated that more than 95 % of the variation could be explained by the fitted models. Temperature at 48.30 °C and
pH at 4.43 were found to be the optimal conditions to obtain oligopeptides from the guts of sea cucumber. The autolysis hydrolysates
prepared at the optimized conditions were further fractionated into four major fractions (I–IV) by size exclusion chromatography
on a Sephadex G-15 column. Fraction IV, which exhibited the highest DPPH radical scavenging capacity, Fe2+-chelating ability and protective effect against hydroxyl radical-induced DNA damage, was then analyzed by ESI–MS for molecular
mass determination and ESI–MS/MS for the characterization of peptides. Two tetrapeptides (Val-Thr-Pro-Tyr and Val-Leu-Leu-Tyr)
and a hexapeptide (Val-Gly-Thr-Val-Glu-Met) were found to exhibit protective effects against hydroxyl radical-induced DNA
damage. These results suggest that antioxidant oligopeptides derived from the guts of sea cucumber by autolysis method could
be utilized for functional foods.
Content Type Journal Article
Category Original Paper
Pages 895-904
DOI 10.1007/s00217-012-1708-9
Authors
Jie Zheng, School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013 People’s Republic of China
Hai-Tao Wu, School of Food Science and Technology, Dalian Polytechnic University, Dalian, 116034 People’s Republic of China
Bei-Wei Zhu, School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013 People’s Republic of China
Xiu-Ping Dong, School of Food Science and Technology, Dalian Polytechnic University, Dalian, 116034 People’s Republic of China
Mao-Mao Zhang, School of Food Science and Technology, Dalian Polytechnic University, Dalian, 116034 People’s Republic of China
Yue-Ling Li, School of Food Science and Technology, Dalian Polytechnic University, Dalian, 116034 People’s Republic of China
Fifteen meat samples collected from pigs (Neckar hybrid line) were selected from 75 animals on the basis of their technological
quality traits, and the samples were classified as normal, PSE, and acid meat. Sensory analysis was performed on the three
meat categories. Total meat protein and drip loss protein were analyzed by electrophoresis (SDS-PAGE), mass spectrometry,
and image analysis. From a sensory point of view, PSE meat was characterized by lower color intensity, and acid meat was characterized
by the lowest score of juiciness. Certain soluble proteins derived from the drip loss were associated with meat quality, especially
phosphoglucomutase and the B chain of hemoglobin in the case of PSE and acid meat. Low quantities of myofibrillar proteins
(myosin LC1, troponin T (TnT) and troponin C (TnC)) in meat with high glycogen levels and low pH levels resulted in a higher
rate of proteolysis of myofibrillar proteins due to higher enzymatic proteolysis activity in the meat. The results of this
study showed that the TnC/TnI ratio may be a pertinent marker of postmortem muscle metabolism and that this ratio is related to textural properties.
Content Type Journal Article
Category Original Paper
Pages 883-894
DOI 10.1007/s00217-012-1705-z
Authors
Elżbieta Żelechowska, Department of Catering Technology and Food Hygiene, Faculty of Human Nutrition and Consumer Sciences, Warsaw University of Life Sciences, SGGW, Nowoursynowska 159c, 02-776 Warsaw, Poland
Wiesław Przybylski, Department of Catering Technology and Food Hygiene, Faculty of Human Nutrition and Consumer Sciences, Warsaw University of Life Sciences, SGGW, Nowoursynowska 159c, 02-776 Warsaw, Poland
Danuta Jaworska, Department of Catering Technology and Food Hygiene, Faculty of Human Nutrition and Consumer Sciences, Warsaw University of Life Sciences, SGGW, Nowoursynowska 159c, 02-776 Warsaw, Poland
Rapid and specific detection of Cronobacter spp. in powdered infant formula milk (IFM) is of great importance for health and safety reasons. In the present study, two
rapid and specific methods, the immunochromatographic strip (ICT) and the matrix-assisted laser desorption ionization-time
of flight mass spectrometry (MALDI-TOF MS), were tested for the detection of Cronobacter spp. in IFM. IFM samples spiked by Cronobacter spp. were correctly detected as positive by both methods. These results were verified by the classical cultivation microbiological
method (ISO/TS 22964:2006). All three methods were used for the analyses of 13 IMF samples from a local market with identical
results. Only one IFM sample was found to be positive. Both tested methods considerably reduced the total detection time,
to 24 h (ICT) and 46 h (MALDI-TOF MS), whereas the reference ISO/TS 22964:2006 method needs 140 h.
Content Type Journal Article
Category Short Communication
Pages 1099-1104
DOI 10.1007/s00217-012-1704-0
Authors
Barbora Javůrková, Department of Biochemistry and Microbiology, Institute of Chemical Technology, Technická 5, 166 28 Prague, Czech Republic
Martina Blažková, Department of Biochemistry and Microbiology, Institute of Chemical Technology, Technická 5, 166 28 Prague, Czech Republic
Ladislav Fukal, Department of Biochemistry and Microbiology, Institute of Chemical Technology, Technická 5, 166 28 Prague, Czech Republic
Pavel Rauch, Department of Biochemistry and Microbiology, Institute of Chemical Technology, Technická 5, 166 28 Prague, Czech Republic
Previous studies have shown that hyperinsulinemia is not only a marker of insulin resistance, but also the causative factor
of peripheral tissue insulin resistance. It also has been suggested that prolonged high-dose insulin treatment can mimic the
effects of hyperinsulinemia and exacerbate insulin resistance in skeletal muscle cells. However, how to prevent or reverse
insulin resistance induced by hyperinsulinemia remains largely unclear. In the past few decades, the use of myricetin as an
anti-diabetic agent has gained much attention, but little information is available regarding the effects of myricetin on glucose
uptake and hyperinsulinemia-induced insulin resistance in skeletal muscle cells. The present study focuses on the effect of
myricetin on insulin signaling in skeletal muscle cell line C2C12 myotubes. Initially, the effect of myricetin under normal
condition was determined. We found that myricetin’s enhancement in glucose uptake coincided with both protein kinase B (Akt)
and AMP-activated protein kinase (AMPK) activities. After that, the role of hyperinsulinemia was investigated. It was showed
that prolonged high-dose insulin treatment inhibited both Akt and AMPK activities. As the results, the low-dose insulin stimulation
of glucose uptake was inhibited by hyperinsulinemia. However, the treatment of myricetin improved low-dose insulin-stimulated
glucose uptake in the hyperinsulinemic state, and this effect essentially depended on the AMPK signal pathway. Together, our
data suggest a putative link between hyperinsulinemia and insulin resistance in C2C12 myotubes, and the myricetin treatment
stimulates glucose uptake and attenuates insulin resistance.
Content Type Journal Article
Category Original Paper
Pages 873-881
DOI 10.1007/s00217-012-1701-3
Authors
Ye Ding, Department of Nutrition and Food Hygiene, School of Public Health, Peking University, Beijing, 100191 People’s Republic of China
Xiao-qian Dai, Department of Nutrition and Food Hygiene, School of Public Health, Peking University, Beijing, 100191 People’s Republic of China
Zhao-feng Zhang, Department of Nutrition and Food Hygiene, School of Public Health, Peking University, Beijing, 100191 People’s Republic of China
Yong Li, Department of Nutrition and Food Hygiene, School of Public Health, Peking University, Beijing, 100191 People’s Republic of China
Methyl eugenol (ME) is a naturally occurring carcinogenic compound found in a number of essential oils including rose oil
distilled from Rosa damascena Mill flowers. In the current study, we evaluate the effect of flower harvesting practices on the ME content in the produced rose
oil. The obtained results show nearly twice reduction in ME content in the rose oil distilled from petals of full-blown flowers.
At the same time, GC/MS analysis of rose oils distilled from stages 3 and 4 rose flower buds (flower buds prior opening of
petals) showed more than 5 times ME reduction and preservation of the relative content of the major rose oil compounds. Moreover,
the comparative study of rose flower yield and rose oil content of rose buds and full-blown flowers showed that harvesting
of rose flower buds results in above three times increase in the formed flower buds from the studied rose plants and more
than twice increase in the rose flower and rose oil yields for the same rose plantation areas. The overall results from this
study allow us to propose a change in the traditional full-blown rose flower harvesting to harvesting of rose flower buds
at stages 3 and 4 during the entire flowering period.
Gelation-like protein hydrolysates from scallop (Patinopecten yessoensis) male gonad (SMG) were obtained by enzymatic hydrolysis using neutrase. Functional properties of SMG hydrolysates (SMGHs)
with different degree of hydrolysis (DH: 4.94, 6.84, 7.53 and 11.86%, respectively) were evaluated with the objective to investigate
the relations between hydrolysis characteristics and functionalities. The results showed that hydrolysis with neutrase improved
the gelation property, solubility, water-holding capacity (WHC), oil-holding capacity (OHC), and surface hydrophobicity (SH),
but not foaming capacity (FC) of SMG. The SMGHs at high DH (11.86%) showed better gelation property and solubility than that
at low DH (4.94–7.53%). However, the maximum values of WHC, OHC, and SH of SMGHs were found at DH of 4.94%, significantly
higher than (p < 0.05) or equivalent to (p > 0.05) that of soy protein isolate (SPI) for WHC and OHC. Emulsifying capacity of SMGHs is independent of DH, but restricted
by pH environment. The emulsifying activity index of all SMGHs was significantly higher than that of SPI in pH 5 (p < 0.05) and slightly higher than or equivalent to that of SPI in pH 7. Meanwhile, SMG and SMGHs were abundant in glycine,
lysine, alanine, glutamic acid, and aspartic acid, containing all the essential amino acids (41.63–42.90% of the total amino
acids). These results imply that SMGHs might be utilized as multifunctional and nutritive ingredients in food industry.
Content Type Journal Article
Category Original Paper
Pages 863-872
DOI 10.1007/s00217-012-1700-4
Authors
Wen-Gang Jin, College of Food Science and Engineering, Northwest A&F University, Yangling Shaanxi, 712100 People’s Republic of China
Hai-Tao Wu, School of Food Science and Technology, Dalian Polytechnic University, Dalian, 116034 People’s Republic of China
Bei-Wei Zhu, College of Food Science and Engineering, Northwest A&F University, Yangling Shaanxi, 712100 People’s Republic of China
Xu-Qin Ran, School of Food Science and Technology, Dalian Polytechnic University, Dalian, 116034 People’s Republic of China
The combined effects of high-pressure homogenization (HPH) and inherent increase in temperature on the survival of Lactobacillus plantarum and Listeria innocua were studied in orange juice. L. innocua was found to be very sensitive to HPH processing, and combination of 110 MPa and 20 °C (48 °C outlet temperature) or 150 MPa
and 20 °C (57 °C outlet temperature) for 2 s was sufficient to achieve a reduction higher than 5 log cycles from the initial
bacterial count. L. plantarum appeared to be more HPH resistant, and no effects on the microbial counts were found up to 80 MPa. Inactivation higher than
5 log cycles of L. plantarum was achieved after HPH treatment at 150 MPa and 19 °C (56 °C outlet temperature) for 20 s or 21 °C (57.5 °C outlet temperature)
for 10 s. Inactivation kinetics of L. plantarum were fitted to a log-linear-tail equation, biphasic and Weibull models. Kinetic parameters increased with outlet temperature
indicating an increase in the inactivation rate. The survivors’ curve showed two subpopulations with different resistance
to HPH treatment. Weibull model was found to be the best candidate to characterize the microbial behavior after HPH processing
being the error in the prediction below 4%. This study shows a novel approach for pasteurization of fruit juices by using
the combined effect of pressure and inherent increase in temperature caused by HPH processing.
Content Type Journal Article
Category Review Paper
Pages 753-760
DOI 10.1007/s00217-012-1698-7
Authors
C. Belloch, Instituto de AgroquÃmica y TecnologÃa de Alimentos (IATA-CSIC), Avda. AgustÃn Escardino, 7, 46980 Paterna, Valencia, Spain
M. C. Gurrea, Instituto de AgroquÃmica y TecnologÃa de Alimentos (IATA-CSIC), Avda. AgustÃn Escardino, 7, 46980 Paterna, Valencia, Spain
A. Tárrega, Instituto de AgroquÃmica y TecnologÃa de Alimentos (IATA-CSIC), Avda. AgustÃn Escardino, 7, 46980 Paterna, Valencia, Spain
F. Sampedro, Center for Animal Health and Food Safety, College of Veterinary Medicine, University of Minnesota, 136G Andrew Boss, 1354 Eckles Avenue, St Paul, MN 55108, USA
J. V. Carbonell, Instituto de AgroquÃmica y TecnologÃa de Alimentos (IATA-CSIC), Avda. AgustÃn Escardino, 7, 46980 Paterna, Valencia, Spain
‘Lemon Myrtle’ is becoming increasingly popular in Europe both for use in cuisine and phytotherapy. However, this common name
covers two completely different species, Backhousia citriodora F. Muell. and Leptospermum citratum Challinor, Cheel & A.R.Penfold. These species differ with respect to secondary compounds and even can cause, if mixed up
and applied in high dose, toxic effects. We describe how the two species can be discriminated microscopically making use of
differences in the morphology of leaf pavement cells and the relative size of palisade parenchyma. Based on the large subunit
of ribulose-1,5-bisphosphate carboxylase oxygenase (rbcL) as molecular marker, the phylogenetic position of the two species
within the Myrtaceae could be clarified. This sequence information was used to develop a simple assay to discriminate the
two species even in dried and highly fragmented mixtures as typically occurring in commercial samples. This assay utilises
the occurrence of single-nucleotide exchanges between those species that produce different fragments when the rbcL amplificates
are restricted with Sac II.
Content Type Journal Article
Category Original Paper
Pages 853-861
DOI 10.1007/s00217-012-1688-9
Authors
Thomas Horn, Molecular Cell Biology, Botanical Institute, Karlsruhe Institute of Technology, Kaiserstr. 2, 76128 Karlsruhe, Germany
Anna Barth, Molecular Cell Biology, Botanical Institute, Karlsruhe Institute of Technology, Kaiserstr. 2, 76128 Karlsruhe, Germany
Michael Rühle, Molecular Cell Biology, Botanical Institute, Karlsruhe Institute of Technology, Kaiserstr. 2, 76128 Karlsruhe, Germany
Annette Häser, Molecular Cell Biology, Botanical Institute, Karlsruhe Institute of Technology, Kaiserstr. 2, 76128 Karlsruhe, Germany
Gabriele Jürges, Molecular Cell Biology, Botanical Institute, Karlsruhe Institute of Technology, Kaiserstr. 2, 76128 Karlsruhe, Germany
Peter Nick, Molecular Cell Biology, Botanical Institute, Karlsruhe Institute of Technology, Kaiserstr. 2, 76128 Karlsruhe, Germany
Animals can be innately attracted to certain odorants. Because these attractants are particularly salient, they might be expected to induce relatively strong responses throughout the olfactory pathway, helping animals detect the most relevant odors but limiting flexibility to respond to other odors. Alternatively, specific neural wiring might link innately preferred odors to appropriate behaviors without a need for intensity biases. How nonpheromonal attractants are processed by the general olfactory system remains largely unknown. In the moth Manduca sexta, we studied this with a set of innately preferred host plant odors and other, neutral odors. Electroantennogram recordings showed that, as a population, olfactory receptor neurons (ORNs) did not respond with greater intensity to host plant odors, and further local field potential recordings showed that no specific amplification of signals induced by host plant odors occurred between the first olfactory center and the second. Moreover, when odorants were mutually diluted to elicit equally intense output from the ORNs, moths were able to learn to associate all tested odorants equally well with food reward. Together, these results suggest that, although nonpheromonal host plant odors activate broadly distributed responses, they may be linked to attractive behaviors mainly through specific wiring in the brain.
Hyperphagia is a reported side effect of anxiolytic benzodiazepines such as chlordiazepoxide (CDP). Prior research has focused primarily on the ingestive responses to sweet or solid foods. We examined CDP effects on licking for normally accepted and avoided taste solutions across a range of concentrations. The effect of CDP (10 mg/kg) versus saline on the licking patterns of water-restricted rats for water and 3 concentrations of sucrose, saccharin, NaCl, monosodium glutamate (MSG), citric acid, and quinine (Q-HCl) solutions was evaluated during 1 h tests. CDP increased meal size for all tastants except citric acid. Analysis of licking microstructure revealed 3 dissociable effects of CDP. CDP affected oromotor coordination as indicated by a uniform increase in the modal interlick interval for all stimuli. CDP increased meal size as indicated by shorter pauses during consumption of water, MSG, and weaker saccharin concentrations, and by fewer long interlick intervals (250–2000 ms) for normally avoided tastants. CDP also increased meal size by increasing burst size, burst duration, and the initial rate of licking for most solutions, suggesting increased hedonic taste evaluation. CDP did not affect variables associated with postingestive feedback such as meal duration or number of bursts, and the results also suggest that CDP did not enhance the perceived taste intensity. We hypothesize that the reduction of pause duration is consistent with an increased motivation to sample the stimulus that synergizes with changes in taste-mediated responsiveness to some but not all stimuli to yield increases in the consumption of both normally accepted and avoided taste stimuli.
Chemesthetic sensations elicited by ibuprofen, extra-virgin olive oil, and capsaicin were compared to quantify perceptual differences between known agonists of TRPA1 and TRPV1. Extra virgin olive oil contains a phenolic compound, oleocanthal, which is thought to share unique chemesthetic qualities with the nonsteroidal anti-inflammatory drug, ibuprofen. Pilot work suggested participants had difficulty distinguishing between multiple chemesthetic subqualities (e.g., burn, sting, itch, tickle, etc.) in a multiattribute rating task. Here, we assessed overall irritation via direct scaling, and a check all that apply task was used to collect information about chemesthetic subqualities over time. Replicated ratings were collected at discrete intervals using the generalized labeled magnitude scale to generate time-intensity curves; maximum intensity (Imax) and area under the curve were extracted for each participant. Intensity responses varied substantially across participants, and within a participant, the relationship was strongest between ibuprofen and olive oil. However, there were also positive, albeit weaker, correlations between capsaicin and ibuprofen and capsaicin and olive oil. The correlation found between olive oil and capsaicin may suggest the presence of unknown TRPV1 agonists in olive oil. This view was also supported by the qualitative data: Capsaicin was described most often as burning and warm/hot, whereas ibuprofen was numbing and tickling. Olive oil shared characteristics with both capsaicin (warm/hot) and ibuprofen (tickle).
Olfactory receptor cells in insects are modulated by neurohormones. Recordings from cockroach olfactory sensilla showed that a subset of sensory neurons increase their responses to selected nonpheromone odorants after octopamine application. With octopamine application, recordings demonstrated increased firing rates by the short but not the long alcohol-sensitive sensilla to the nonpheromone volatile, hexan-1-ol. Within the same sensillum, individual receptor cells are shown to be modulated independently from each other, indicating that the octopamine receptors reside in the receptor not in the accessory cells. A uniform decrease in the amplitude of electroantennogram, which is odorant independent, is suggested to reflect the rise in octopamine concentration in the antennal hemolymph. Perception of general odorants measured as behavioral responses changed qualitatively under octopamine treatment: namely, repulsive hexan-1-ol became neutral, whereas neutral eucalyptol became attractive. Octopamine induced a change in male behavioral responses to general odors that were essentially the same as in the state of sexual arousal. Our findings suggest that sensitivity to odors having different biological significances is modulated selectively at the peripheral as well as other levels of olfactory processing.
Rats can be classified as either sucralose avoiders (SA) or sucralose preferrers (SP) based on their behavioral responses in 2-bottle preference, 1-bottle intake, and brief-access licking tests. The present study demonstrates that this robust phenotypic variation in the preference for sucralose predicts acceptance of saccharin, an artificial sweetener with a purported concentration-dependent "bitter" side taste and a 0.25 M sucrose solution adulterated with increasing concentrations of quinine hydrochloride (QHCl). Specifically, SA displayed decreased preference for and intakes of saccharin (≥41.5 mM) and sucrose–QHCl (>0.5 mM QHCl) solutions, relative to SP. In a second experiment involving brief-access (30-s) tests, SP and SA did not differ in their unconditioned licking responses across a range of sodium chloride or QHCl solutions (0.03–1 mM). However, the acceptability threshold for sucrose was lower in SA, relative to SP (0.06 and 0.13 M, respectively). Our findings suggest that phenotypic differences in sucralose preference are indicative of a more general difference in the hedonic processing of stimuli containing "bittersweet" or "sweet" taste qualities.
Previously, published studies have reported mixed results regarding the role of the TRPM5 cation channel in signaling sweet taste by taste sensory cells. Some studies have reported a complete loss of sweet taste preference in TRPM5 knockout (KO) mice, whereas others have reported only a partial loss of sweet taste preference. This study reports the results of conditioned aversion studies designed to motivate wild-type (WT) and KO mice to respond to sweet substances. In conditioned taste aversion experiments, WT mice showed nearly complete LiCl-induced response suppression to sucrose and SC45647. In contrast, TRPM5 KO mice showed a much smaller conditioned aversion to either sweet substance, suggesting a compromised, but not absent, ability to detect sweet taste. A subsequent conditioned flavor aversion experiment was conducted to determine if TRPM5 KO mice were impaired in their ability to learn a conditioned aversion. In this experiment, KO and WT mice were conditioned to a mixture of SC45647 and amyl acetate (an odor cue). Although WT mice avoided both components of the stimulus mixture, they avoided SC45647 more than the odor cue. The KO mice also avoided both stimuli, but they avoided the odor component more than SC45647, suggesting that while the KO mice are capable of learning an aversion, to them the odor cue was more salient than the taste cue. Collectively, these findings suggest the TRPM5 KO mice have some residual ability to detect SC45647 and sucrose, and, like bitter, there may be a TRPM5-independent transduction pathway for detecting these substances.
In this study, we have investigated how the function of native and recombinant nicotinic acetylcholine receptors (nAChRs) is modulated by the monoterpenoid alcohol from peppermint (–) menthol. In trigeminal neurons (TG), we found that nicotine (75 μM)-activated whole-cell currents through nAChRs were reversibly reduced by menthol in a concentration-dependent manner with an IC50 of 111 μM. To analyze the mechanism underlying menthol's action in more detail, we used single channel and whole-cell recordings from recombinant human α4β2 nAChR expressed in HEK tsA201 cells. Here, we found a shortening of channel open time and a prolongation of channel closed time, and an increase in single channel amplitude leading in summary to a reduction in single channel current. Furthermore, menthol did not affect nicotine's EC50 value for currents through recombinant human α4β2 nAChRs but caused a significant reduction in nicotine's efficacy. Taken together, these findings indicate that menthol is a negative allosteric modulator of nAChRs.
Physiological studies on olfaction frequently ignore the airborne quantities of stimuli reaching the sensory organ. We used a gas chromatography–calibrated photoionization detector to estimate quantities released from standard Pasteur pipette stimulus cartridges during repeated puffing of 27 compounds and verified how lack of quantification could obscure olfactory sensory neuron (OSN) affinities. Chemical structure of the stimulus, solvent, dose, storage condition, puff interval, and puff number all influenced airborne quantities. A model including boiling point and lipophilicity, but excluding vapor pressure, predicted airborne quantities from stimuli in paraffin oil on filter paper. We recorded OSN responses of Drosophila melanogaster, Ips typographus, and Culex quinquefasciatus, to known quantities of airborne stimuli. These demonstrate that inferred OSN tuning width, ligand affinity, and classification can be confounded and require stimulus quantification. Additionally, proper dose–response analysis shows that Drosophila AB3A OSNs are not promiscuous, but highly specific for ethyl hexanoate, with other earlier proposed ligands 10- to 10 000-fold less potent. Finally, we reanalyzed published Drosophila OSN data (DoOR) and demonstrate substantial shifts in affinities after compensation for quantity and puff number. We conclude that consistent experimental protocols are necessary for correct OSN classification and present some simple rules that make calibration, even retroactively, readily possible.
The capacity of the mammalian olfactory system to detect an enormous collection of different chemical compounds is based on a large repertoire of odorant receptors (ORs). A small group of these ORs, the OR37 family, is unique due to a variety of special features. Members of this subfamily are exclusively found in mammals, they share a high degree of sequence homology and are highly conserved during evolution. It is still elusive which odorants may activate these atypical receptors. We have reasoned that compounds from skin, hairs, or skin glands might be potential candidates. We have exposed mice to such compounds and monitored activation of glomeruli through the expression of the activity marker c-fos in juxtaglomerular cells surrounding ventrally positioned glomeruli in the olfactory bulb (OB). Employing this methodology it was found that stimulation with long-chain alkanes elicits activation in the ventral part of the OB, however, none of the OR37 glomeruli. Analyses of long-chain hydrocarbon compounds with different functional groups revealed that long-chain aliphatic aldehydes elicited an activation of defined OR37 glomeruli, each of them responding preferentially to an aldehyde with different chain lengths. These results indicate that OR37 receptors may be tuned to distinct fatty aldehydes with a significant degree of ligand specificity.
