The study evaluated the stability of an oligopeptide(Lys-Arg-Gln-Lys-Tyr-Asp,KRQKYD)and its transport mechanism by simulating gastrointestinal digestion and a model of human intestinal Caco-2 monolayer cells in vitro....The study evaluated the stability of an oligopeptide(Lys-Arg-Gln-Lys-Tyr-Asp,KRQKYD)and its transport mechanism by simulating gastrointestinal digestion and a model of human intestinal Caco-2 monolayer cells in vitro.In this study,the effects of environmental factors(temperature,pH and NaCl concentration)and simulated gastrointestinal digestion on the stability of KRQKYD were evaluated by indicators of the levels of alanine transaminase(ALT),aspartate transaminase(AST)and malondialdehyde(MDA)in an alcoholinduced hepatocyte injury model.The results showed that KRQKYD still maintained satisfactory hepatocyteprotective activity after treatment with different temperatures(20-80℃),pH(3.0-9.0),NaCl concentration(1%-7%)and simulated gastrointestinal digestion,which indicated that KRQKYD showed good stability to environmental factors and simulated gastrointestinal digestion.Furthermore,the intact KRQKYD could be absorbed in a model of Caco-2 monolayer cells with a P_(app)value of(9.70±0.53)×10^(-7)cm/s.Pretreatment with an energy inhibitor(sodium azide),a competitive peptide transporter inhibitor(Gly-Pro)and a transcytosis inhibitor wortmannin did not decrease the level of transepithelial KRQKYD transport,indicating that the transport mechanism of KRQKYD was not associated with energy dependent,vector mediated and endocytosis.The tight junction disruptor cytochalasin D significantly increased the level of transepithelial KRQKYD transport(P<0.05),suggesting that intact KRQKYD was absorbed by paracellular transport.展开更多
To investigate the spoilage characteristics of Jinhua ham,sensory scores,volatile compounds,biogenic amine,physicochemical parameters and microbial counts were evaluated between normal and spoiled hams.The results sho...To investigate the spoilage characteristics of Jinhua ham,sensory scores,volatile compounds,biogenic amine,physicochemical parameters and microbial counts were evaluated between normal and spoiled hams.The results showed that off-odors of spoiled hams were dominated by rancid,sour,sulfide and ammonia odors derived from these compounds including butanoic acid,methanethiol and dimethyl disulfide.Total content of biogenic amine in spoiled hams was significantly higher(more than 10-fold)compared with normal hams,and putrescine,cadaverine and histamine were the key components of biogenic amine of spoiled hams.Lower salt content,and higher moisture,TVB-N and thiobarbituric acid reactive substances(TBARS)values were observed in spoiled hams compared with normal hams.The populations of Enterobacteriaceae and Enterococcus of spoiled hams were obviously higher than that of normal hams.High moisture and low salt content caused the abnormal growth of Enterobacteriaceae and Enterococcus in spoiled hams,which contributed to the spoilage of Jinhua ham.展开更多
本研究以现代加工工艺条件下生产制作的金华火腿为研究对象,评估了因单增李斯特菌而引起食物中毒的风险。通过调查生猪肉中单增李斯特菌的初始污染率及污染水平,金华火腿生产及销售过程中影响单增李斯特菌生长的参数,如pH、水分活度、...本研究以现代加工工艺条件下生产制作的金华火腿为研究对象,评估了因单增李斯特菌而引起食物中毒的风险。通过调查生猪肉中单增李斯特菌的初始污染率及污染水平,金华火腿生产及销售过程中影响单增李斯特菌生长的参数,如pH、水分活度、温度以及乳酸菌含量等,再结合单增李斯特菌生长模型,模拟其暴露水平,并评估了不同人群因食用即食金华火腿切片而患李斯特菌病的风险。结果显示:金华火腿零售时污染水平为-9.47~7.05 lg CFU/g(90%的置信区间);健康成年人食用即食金华火腿切片的平均患病概率小于10^(-15),易感人群的平均患病概率小于10^(-13)。食用即食金华火腿切片而患李斯特菌病的风险较低,金华火腿的现代加工工艺对于单增李斯特菌的控制水平可以与国际接轨。本研究首次定量模拟了金华火腿从生猪肉到腌制发酵至最终产品的全过程中单增李斯特菌的暴露情况,为发酵火腿中食源性致病菌的风险评估提供了参考模型。展开更多
基金supported by the Major special project of Anhui Province (2021d06050001)the Major Science and Technology Project of Anhui Province (201903b06020004)+1 种基金the Natural Science Foundation of Anhui Province (2308085QC115)the Special Fund for Anhui Province Agricultural Products Processing Industry Technology System (340000211260001000420)。
文摘The study evaluated the stability of an oligopeptide(Lys-Arg-Gln-Lys-Tyr-Asp,KRQKYD)and its transport mechanism by simulating gastrointestinal digestion and a model of human intestinal Caco-2 monolayer cells in vitro.In this study,the effects of environmental factors(temperature,pH and NaCl concentration)and simulated gastrointestinal digestion on the stability of KRQKYD were evaluated by indicators of the levels of alanine transaminase(ALT),aspartate transaminase(AST)and malondialdehyde(MDA)in an alcoholinduced hepatocyte injury model.The results showed that KRQKYD still maintained satisfactory hepatocyteprotective activity after treatment with different temperatures(20-80℃),pH(3.0-9.0),NaCl concentration(1%-7%)and simulated gastrointestinal digestion,which indicated that KRQKYD showed good stability to environmental factors and simulated gastrointestinal digestion.Furthermore,the intact KRQKYD could be absorbed in a model of Caco-2 monolayer cells with a P_(app)value of(9.70±0.53)×10^(-7)cm/s.Pretreatment with an energy inhibitor(sodium azide),a competitive peptide transporter inhibitor(Gly-Pro)and a transcytosis inhibitor wortmannin did not decrease the level of transepithelial KRQKYD transport,indicating that the transport mechanism of KRQKYD was not associated with energy dependent,vector mediated and endocytosis.The tight junction disruptor cytochalasin D significantly increased the level of transepithelial KRQKYD transport(P<0.05),suggesting that intact KRQKYD was absorbed by paracellular transport.
基金supported by National Natural Science Foundation of China(3210197532022066+7 种基金31871825)National Key Research&Development Program of China(2021YFD2100104)Modern Agricultural Technical Foundation of China(CARS-42-25)Zhejiang Province Natural Science Foundation(LQ22C200017)China Postdoctoral Foundation(2020M6818062021T140348)Science and Technology Programs of Ningbo(202003N4130202002N3067)。
文摘To investigate the spoilage characteristics of Jinhua ham,sensory scores,volatile compounds,biogenic amine,physicochemical parameters and microbial counts were evaluated between normal and spoiled hams.The results showed that off-odors of spoiled hams were dominated by rancid,sour,sulfide and ammonia odors derived from these compounds including butanoic acid,methanethiol and dimethyl disulfide.Total content of biogenic amine in spoiled hams was significantly higher(more than 10-fold)compared with normal hams,and putrescine,cadaverine and histamine were the key components of biogenic amine of spoiled hams.Lower salt content,and higher moisture,TVB-N and thiobarbituric acid reactive substances(TBARS)values were observed in spoiled hams compared with normal hams.The populations of Enterobacteriaceae and Enterococcus of spoiled hams were obviously higher than that of normal hams.High moisture and low salt content caused the abnormal growth of Enterobacteriaceae and Enterococcus in spoiled hams,which contributed to the spoilage of Jinhua ham.
文摘本研究以现代加工工艺条件下生产制作的金华火腿为研究对象,评估了因单增李斯特菌而引起食物中毒的风险。通过调查生猪肉中单增李斯特菌的初始污染率及污染水平,金华火腿生产及销售过程中影响单增李斯特菌生长的参数,如pH、水分活度、温度以及乳酸菌含量等,再结合单增李斯特菌生长模型,模拟其暴露水平,并评估了不同人群因食用即食金华火腿切片而患李斯特菌病的风险。结果显示:金华火腿零售时污染水平为-9.47~7.05 lg CFU/g(90%的置信区间);健康成年人食用即食金华火腿切片的平均患病概率小于10^(-15),易感人群的平均患病概率小于10^(-13)。食用即食金华火腿切片而患李斯特菌病的风险较低,金华火腿的现代加工工艺对于单增李斯特菌的控制水平可以与国际接轨。本研究首次定量模拟了金华火腿从生猪肉到腌制发酵至最终产品的全过程中单增李斯特菌的暴露情况,为发酵火腿中食源性致病菌的风险评估提供了参考模型。
