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Effects of metal ions on formation of acrylamide and 5‐hydroxymethylfurfural in asparagine–glucose model system
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Chao Wen Xingbo Shi Zimeng Wang Wenli Gao Liwen Jiang Qian Xiao Xia Liu Fangming Deng 《International Journal of Food Science & Technology》2016,51(2):279-285
Undesirable substances of thermal food processing such as acrylamide (AA) and 5‐hydroxymethylfurfural (HMF) have been intensively studied in recent decades. The aim of this work was to investigate the evolution mechanism of AA and HMF contents in the presence of various valence metal cations at various concentrations in asparagine–glucose model system. Three interesting phenomena were found. Firstly, the AA contents first decreased and then increased, whereas the HMF contents first increased and then decreased, with increasing metal cations concentration; secondly, the concentration of cations for maximal HMF contents was lower than the concentration of cations for minimal AA contents; thirdly, the maximum AA‐inhibiting or HMF‐promoting efficiency was achieved more readily with trivalent, then divalent and lastly monovalent cations. These phenomena can be explained by that increasing the metal cations concentration can increase the protonated product contents, thus increasing the AA‐inhibiting efficiency and HMF‐promoting efficiency. With higher metal cations concentration in the model system, HMF as a reactant can react with the asparagine to form AA or directly decompose into furfural. These interesting results can provide a theoretical foundation to simultaneously control the formation of AA and HMF during food processing. 相似文献
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Hiroyuki Kataoka Mina Miyake Sachiko Nishioka Tomoko Matsumoto Keita Saito Kurie Mitani 《Molecular nutrition & food research》2010,54(7):1039-1048
Heterocyclic amines (HCAs) are mutagenic and carcinogenic compounds found in cooked meat and fish. Although HCAs are known to form adducts with protein after metabolic activation, adduct formation during cooking has not been elucidated. In this study, we showed that 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP) is released from high molecular weight compounds by acid or enzymatic hydrolysis of cooked foods. Formation of free and protein adduct forms of PhIP was dependent on cooking temperature and time, and PhIP–protein adducts were estimated to form after formation of free PhIP. We also demonstrated that PhIP–protein adduct is formed by heating of PhIP and albumin as a model protein. A new adduct peak including [M+H]+ (m/z=225) of PhIP as a fragment ion was detected in the high molecular weight fraction of heat‐treated protein by LC–MS analysis. From model experiments by heating of PhIP and amino acids, the adduct was estimated to be produced by condensation of the amino group of PhIP and the carboxyl group of protein. PhIP–protein adducts were detected in several cooked meat and fish at ng/g food level as PhIP content. These results suggest that food‐borne protein adducts of HCAs may influence human HCA exposure and carcinogenic risk. 相似文献
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The (1–3, 1–4)‐β‐Glucanases in Malting Barley: Enzyme Survival and Genetic and Environmental Effects
J.E. Georg‐Kraemer E. Caiero E. Minella J.F. Barbosa‐Neto S.S. Cavalli 《Journal of the Institute of Brewing》2004,110(4):303-308
Eighteen barley genotypes used in Brazilian malting barley breeding programs were characterized in relation to (1–3, 1–4)‐β‐glucanase activity in green and kilned malt. They were tested to determine the loss of enzyme activity during kilning in the malting process and the environmental effects on enzyme activity were measured. The genotypes analyzed showed great variation regarding the enzyme activity in both kinds of malt, in a range from 531.94 to 934.31 U/kg in green malt, and from 187.02 to 518.40 U/kg in dry malt. The mean enzyme activity loss during kilning was close to 60%, very similar to the results obtained in other studies. The loss among genotypes varied from 8.04% to 71.54%. The enzyme activity varied significantly under the different environments tested, showing existence of environmental effects on the genotypes analyzed. Embrapa 127 was the genotype that exhibited the highest enzyme activity in finished malt although it had shown a low activity in green malt, reflecting a negligible loss of activity during kilning. The data indicate promising results to malting barley breeding due to the wide variability exhibited by genotypes as to enzyme activity and levels of isoenzyme with high thermostability. 相似文献
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Study on microwave‐accelerated casein protein grafted with glucose and β‐cyclodextrin to improve the gel properties
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Weiwei Bi Weili Zhao Xiaodong Li Wei Ge Zafarullah Muhammad Haixia Wang Lingling Du 《International Journal of Food Science & Technology》2015,50(6):1429-1435
The effect of glycosylation treatment coupled with microwave heating (MH) on gel properties and structure change of casein were investigated. Conjugation was confirmed by electrophoresis. Protein disulphide bonds were broken by microwave irradiation to create an increase first and a decrease later in free sulfhydryl contents with time, thereby inducing subunit disaggregation. Also, the exposure of hydrophobic core residues was increased in MH‐treated casein, which brings about protein disaggregation and unfolding. It showed that graft reactions by MH had much faster than those by water bath heating (WH). The content of disulphide bonds is 7.2% and 6.0% in the casein–glucose and casein–β‐cyclodextrin, respectively, treated by MH which was reduced significantly than that of treated by WH. Moreover, MH can increase the hardness of the gel. Consequently, MH could improve the efficiency of the reaction and gel properties. 相似文献
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Screening of β‐Glucosidase and β‐Xylosidase Activities in Four Non‐Saccharomyces Yeast Isolates
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The finding of new isolates of non‐Saccharomyces yeasts, showing beneficial enzymes (such as β‐glucosidase and β‐xylosidase), can contribute to the production of quality wines. In a selection and characterization program, we have studied 114 isolates of non‐Saccharomyces yeasts. Four isolates were selected because of their both high β‐glucosidase and β‐xylosidase activities. The ribosomal D1/D2 regions were sequenced to identify them as Pichia membranifaciens Pm7, Hanseniaspora vineae Hv3, H. uvarum Hu8, and Wickerhamomyces anomalus Wa1. The induction process was optimized to be carried on YNB‐medium supplemented with 4% xylan, inoculated with 106 cfu/mL and incubated 48 h at 28 °C without agitation. Most of the strains had a pH optimum of 5.0 to 6.0 for both the β‐glucosidase and β‐xylosidase activities. The effect of sugars was different for each isolate and activity. Each isolate showed a characteristic set of inhibition, enhancement or null effect for β‐glucosidase and β‐xylosidase. The volatile compounds liberated from wine incubated with each of the 4 yeasts were also studied, showing an overall terpene increase (1.1 to 1.3‐folds) when wines were treated with non‐Saccharomyces isolates. In detail, terpineol, 4‐vinyl‐phenol and 2‐methoxy‐4‐vinylphenol increased after the addition of Hanseniaspora isolates. Wines treated with Hanseniaspora, Wickerhamomyces, or Pichia produced more 2‐phenyl ethanol than those inoculated with other yeasts. 相似文献
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Inhibition of 2‐Amino‐1‐methyl‐6‐phenylimidazo [4,5‐b]pyridine (PhIP) Formation by Alkoxy Radical Scavenging of Flavonoids and Their Quantitative Structure–Activity Relationship in a Model System
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The inhibitory effect of 10 flavonoids on the formation of 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP) in a creatinine–phenylalanine model system was investigated through electronic spin resonance and a quantitative structure–activity relationship. Alkoxy radicals were observed during the heating process, providing evidence for a radical pathway in the formation of PhIP. The alkoxy radical scavenging capability of the flavonoids was proportional to their inhibition of PhIP formation (IC50). We deduced that flavonoid inhibition of PhIP generation occurs via scavenging of alkoxy radicals during the heating process. Multiple linear regression and partial least squares models were used to elucidate the relationship between PhIP inhibition activity and structure characteristics of the flavonoids. The lipo–hydro partition coefficient and molecular fractional polar surface area of the flavonoids were found to be predictive of the inhibition effect. 相似文献
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Simultaneous Analysis of Nε‐(Carboxymethyl)Lysine and Nε‐(Carboxyethyl)Lysine in Foods by Ultra‐Performance Liquid Chromatography‐Mass Spectrometry with Derivatization by 9‐Fluorenylmethyl Chloroformate
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Yanqiong Zhou Qin Lin Cheng Jin Lu Cheng Xiaoyan Zheng Ming Dai Ying Zhang 《Journal of food science》2015,80(2):C207-C217
Isotope dilution ultra‐performance liquid chromatography–electrospray tandem mass spectrometry with derivatization by 9‐fluorenylmethyl chloroformate was successfully applied to quantify Nε‐(carboxymethyl)lysine (CML) and Nε‐(carboxyethyl)lysine (CEL) in processed foods. We demonstrate that this analytical method is well validated for the determination of CML and CEL contents in processed foods. Relative standard deviations (RSD) indicate repeatability (RSD < 6% for CML and CEL) and reproducibility (RSD < 6% for CML and < 7% for CEL) in this method. Percent recovery is also good. We obtain recoveries of 102% to 112% for CML and 86% to 114% for CEL. CML levels detected in the samples vary from 2.29 to 480 mg/kg food, whereas CEL is detected in significantly lower concentrations ranging from 0.56 to 107 mg/kg food. These data could help consumers make better food choices by monitoring intake of advanced glycation end‐products, which may pose a risk to human health. 相似文献
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Effects of oxidised linoleic acid on the formation of Nε‐carboxymethyl‐lysine and Nε‐carboxyethyl‐lysine in Maillard reaction system
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Ligang Yu Zhiyong He Maomao Zeng Zongping Zheng Jialiang He Mengle Wang Jie Chen 《International Journal of Food Science & Technology》2016,51(3):742-752
This study investigated the effects of oxidised linoleic acid (18:2) on Nε‐carboxymethyl‐lysine (CML) and Nε‐carboxyethyl‐lysine (CEL) formation in Maillard reaction systems. Model systems of lysine/glucose (L/G), lysine/18:2 (L/18:2), lysine/18:2/glucose (L/18:2/G), myofibrillar protein/glucose (MFP/G), MFP/18:2 and MFP/18:2/G were maintained at 37 °C for 6 weeks. The results showed that CML/CEL contents in L/G (6.99 and 0.96 mmol mol?1 lysine, respectively) were significantly higher than those in L/18:2/G (1.43 and 0.41 mmol mol?1 lysine, respectively), and there is a small amount of CML/CEL generation in L/18:2. However, the CML/CEL levels in MFP/G (197.2 and 83.8 ng mg?1 protein, respectively) were markedly lower than those in MFP/18:2/G (283.2 and 118.5 ng mg?1 protein, respectively). 18:2 favours the formation of CML/CEL in MFP/18:2/G, not in L/18:2/G. All these findings indicated that the role of 18:2 on CML/CEL formation in Maillard reaction system was complex, and depended on CML/CEL formation rate and substrate types (lysine or lysine residue in protein). 相似文献
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This study explored the dose‐dependent effect of oat cereal β‐glucan on improving metabolic indexes of obesity mice. C57‐Bl mice were randomized to chow diet (N) group and high fat diet group and other three doses of oat β‐glucan groups (low β‐glucan, medium β‐glucan, and high β‐glucan). Energy intake, glucose, lipids, and appetite related hormones were tested. Dose‐dependent relation was observed on oat β‐glucan doses and body weight change, average energy intake, total cholesterol, HDL cholesterol, plasma neural peptide Y, arcuate neural peptide Y mRNA, and arcuate neural peptide Y receptor 2 mRNA level. Oat β‐glucan helped to increase plasma peptide Y‐Y and intestine peptide Y‐Y expression in obesity mice. 相似文献
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Lack of β, β‐carotene‐9′, 10′‐oxygenase 2 leads to hepatic mitochondrial dysfunction and cellular oxidative stress in mice
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Lei Wu Xin Guo Steven D. Hartson Mary Abby Davis Hui He Denis M. Medeiros Weiqun Wang Stephen L. Clarke Edralin A. Lucas Brenda J. Smith Johannes von Lintig Dingbo Lin 《Molecular nutrition & food research》2017,61(5)
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Antônio Eduardo Miller Crotti Paul J. Gates João Luis Callegari Lopes Norberto Peporine Lopes 《Molecular nutrition & food research》2010,54(3):433-439
The β‐carbolines 1‐methyl‐9H‐pyrido [3,4‐b]indole and 9H‐pyrido[3,4b]indole have been implicated as having causative roles in a number of human diseases, such as Parkinson's disease and cancer. As they can be formed during the heating of protein‐rich food, a number of analytical methodologies have been proposed for their detection and quantification in foodstuff. For this purpose, LC‐MS and LC‐MS/MS have emerged as the most specific analytical methods, and the quantification is based on the occurrence of unusual ions, such as [M+H‐(H?)]+ and [M+H‐2H]+. In this study, we have investigated the formation of these ions by accurate‐mass electrospray MS/MS and demonstrated that these ions are formed from gas‐phase ion‐molecule reactions between water vapor present in the collision cell and the protonated molecule of 1‐methyl‐9H‐pyrido [3,4‐b]indole and 9H‐pyrido[3,4b]indole. Although this reaction has been previously described for heterocyclic amine ions, it has been overlooked in the most of recent LC‐MS and LC‐MS/MS studies, and no complete data of the fragmentation are reported. Our results demonstrate that additional attention should be given with respect to eliminating water vapor residues in the mass spectrometer when analysis of β‐carbolines is performed, as this residue may affect the reliability in the results of quantification. 相似文献
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Characterization of the Supermolecular Structure of Polydatin/6‐O‐α‐Maltosyl‐β‐cyclodextrin Inclusion Complex
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Benguo Liu Yun Li Huizhi Xiao Yonglan Liu Haizhen Mo Hanjun Ma Guizhao Liang 《Journal of food science》2015,80(6):C1156-C1161
Polydatin is the main bioactive ingredient in many medicinal plants, such as Hu‐zhang (Polygonum cuspidatum), with many bioactivities. However, its poor aqueous solubility restricts its application in functional food. In this work, 6‐O‐α‐Maltosyl‐β‐cyclodextrin (Malt‐β‐CD), a new kind of β‐CD derivative was used to enhance the aqueous solubility and stability of polydatin by forming the inclusion complex. The phase solubility study showed that polydatin and Malt‐β‐CD could form the complex with the stoichiometric ratio of 1:1. The supermolecular structure of the polydatin/Malt‐β‐CD complex was characterized by ultraviolet–visible spectroscopy (UV), Fourier transform infrared spectroscopy (FT‐IR), X‐ray diffractometry (XRD), thermogravimetric/differential scanning calorimetry (TG/DSC), and proton nuclear magnetic resonance (1H‐NMR) spectroscopy. The changes of the characteristic spectral and thermal properties of polydatin suggested that polydatin could entrap inside the cavity of Malt‐β‐CD. Furthermore, to reasonably understand the complexation mode, the supermolecular structure of polydatin/Malt‐β‐CD inclusion complex was postulated by a molecular docking method based on Autodock 4.2.3. It was clearly observed that the ring B of polydatin oriented toward the narrow rim of Malt‐β‐CD with ring A and glucosyl group practically exposed to the wide rim by hydrogen bonding, which was in a good agreement with the spectral data. 相似文献
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The role of pulsed electric fields treatment in enhancing the stability of amino acid – sugar complexes:‐ interactions between L‐Phenylalanine and β‐Cyclodextrin
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Zhi‐Hong Zhang Lang‐Hong Wang Xin‐An Zeng Charles S. Brennan Margaret Brennan Zhong Han 《International Journal of Food Science & Technology》2016,51(9):1988-1996
In this work, the effect of pulsed electric fields (PEF) treatment on the interactions between amino acids (using L‐Phenylalanine: L‐Phe) and sugar (using β‐Cyclodextrin: β‐CD) complex was analysed by fluorescence spectroscopy, Raman spectroscopy and simultaneous thermal analyzer. Moreover, the molecular dynamics of β‐CD–L‐Phe inclusion complex treated by PEF was calculated by molecular modelling. The results indicated that β‐CD–L‐Phe complexes are formed by a molar ratio of 1:1, and the stability constant of such complexes increased from 147 to 614 M?1 by PEF treatment. Thermal characterisations of β‐CD–L‐Phe complexes indicated that the PEF treatment could increase the yield of complexes. The PEF treatment resulted in an increase in the reaction enthalpy of β‐CD–L‐Phe inclusion complexes by DSC curve. These results show that PEF treatment has the potential to promote the chemical processing, especially the small organic molecules participate in inclusion or cross‐linking reaction. 相似文献