通讯机构：
[Yanyang Wu] H;Horticulture and Landscape College, Hunan Agricultural University, Changsha 410128, China<&wdkj&>Hunan Co-Innovation Center for Utilization of Botanical Functional Ingredients, Changsha 410128, China<&wdkj&>Key Laboratory for Food Science and Biotechnology of Hunan Province, College of Food Science and Technology, Hunan Agricultural University, Changsha 410128, China<&wdkj&>State Key Laboratory of Subhealth Intervention Technology, Changsha 410128, China<&wdkj&>Author to whom correspondence should be addressed.
关键词：
egg;diabetes;vitamin B6;islet beta cells
摘要：
Vitamin B6 may alleviate diabetes by regulating insulin secretion and increasing insulin sensitivity, but its mechanism remains to be explored. In this study, vitamin B6-mediated autophagy and high glucose-induced apoptosis were tested to investigate the mechanism by which vitamin B6 regulates insulin release. The results showed that 20 mM glucose increased the apoptosis rate from 10.39% to 22.44%. Vitamin B6 reduced the apoptosis rate of RIN-m5F cells from 22.44% to 11.31%. Our data also showed that the vitamin B6 content in processed eggs was decreased and that the hydrothermal process did not affect the bioactivity of vitamin B6. Vitamin B6 increased the number of autophagosomes and the ratio of autophagosome marker protein microtubule associated protein 1 light chain 3 beta to microtubule associated protein 1 light chain 3 alpha (LC3-II/LC3-I). It also decreased the amount of sequetosome 1 (SQSTM1/p62) and inhibited the phosphorylation of p70 ribosomal protein S6 kinase (p70S6K) under normal and high glucose stress. Another study showed that vitamin B6 inhibited the apoptosis rate, whereas the autophagy inhibitor 3-methyladenine (3-MA) blocked the protective effect of vitamin B6 against apoptosis induced by high glucose. The hydrothermal process decreased the vitamin B6 content in eggs but had no effect on the cytoprotective function of vitamin B6 in RIN-m5f cells. In conclusion, we demonstrated that vitamin B6-mediated autophagy protected RIN-m5f cells from high glucose-induced apoptosis might via the mTOR-dependent pathway. Our data also suggest that low temperatures and short-term hydrothermal processes are beneficial for dietary eggs.
关键词：
Chaling red sufu;Flavor compounds;Microbial community;Relationship
摘要：
Sufu, a traditional Chinese fermented soybean product, has a variety of flavors due to fermentation. However, the relationship between the formation of these flavors and microorganisms in the fermentation process is not clearly understood. In this study, the dynamic changes of the microbial diversity, free amino acids (FAAs), free fatty acids (FFAs) and volatile flavor compounds (VFCs) of Sufu during the post-fermentation process were investigated. The results indicated that a range of VFCs, including phenylacetaldehyde, linalool, 2-pentyl-furan were formed during the post-fermentation. The main FFAs found in these Sufu samples were linoleic acid, oleic acid and arachidic acid and the most predominant FAA was glutamic acid, which highly contributed to the taste characteristic of Sufu. The correlation analysis result discovered that Leuconostoc, Lactobacillus, Weissella, Debaryomyces, Tausonia and Pichia were the main microorganisms responsible for the flavor formation of Sufu. In addition, it was found for the first time that Chaling red Sufu could produce a cream milk aroma of nonanoic acid, which strongly positive correlated with Rhodotorula. It is expected that these findings will provide new insight into the flavor formation of conventionally fermented soybean foods.
作者机构：
[Rao, Zhenghua; Feng, Shengnan; Feng, Xiaohui; Meng, Qingshi; Li, Jing; Zhang, Longchao; Wang, Yujiao] Chinese Acad Agr Sci, Inst Anim Sci, State Key Lab Anim Nutr, Beijing 100193, Peoples R China.;[Li, Jing] Zhengzhou Univ, Sch Agr Sci, Zhengzhou 450001, Peoples R China.;[Wang, Yujiao] Hunan Agr Univ, Coll Food Sci & Technol, Changsha 410128, Peoples R China.;[Liu, Hai] Beijing Heiliu Anim Husb Technol Co Ltd, Beijing 102211, Peoples R China.
通讯机构：
[Qingshi Meng] A;A State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China<&wdkj&>Author to whom correspondence should be addressed.
关键词：
lipidome;metabolome;lipid oxidation;pork;freezing process
摘要：
Frozen storage is an important strategy to maintain meat quality for long-term storage and transportation. Lipid oxidation is one of the predominant causes of the deterioration of meat quality during frozen storage. Untargeted lipidomic and targeted metabolomics were employed to comprehensively evaluate the effect of frozen duration on pork lipid profiles and lipid oxidative products including free fatty acids and fatty aldehydes. A total of 688 lipids, 40 fatty acids and 14 aldehydes were successfully screened in a pork sample. We found that ether-linked glycerophospholipids, the predominant type of lipids, gradually decreased during frozen storage. Of these ether-linked glycerophospholipids, ether-linked phosphatidylethanolamine and phosphatidylcholine containing more than one unsaturated bond were greatly influenced by frozen storage, resulting in an increase in free polyunsaturated fatty acids and fatty aldehydes. Among these lipid oxidative products, decanal, cis-11,14-eicosenoic acid and cis-5,8,11,14,17-dicosapentaenoic acid can be considered as potential indicators to calculate the freezing time of unknown frozen pork samples. Moreover, over the three-month frozen storage, the first month was a rapid oxidation stage while the other two months were a slow oxidation stage.
作者机构：
[Deng, Fangming; Wang, Zengguang; Ma, Ding; Zhao, Lingyan] Hunan Agr Univ, Coll Food Sci & Technol, Changsha 410000, Peoples R China.;[Li, Yong] Univ Hawaii Manoa, Dept Human Nutr, Food & Anim Sci, Honolulu, HI 96822 USA.;[Wu, Zhongkun; Kang, Wenli; Dai, Zhiyong; Wang, Jiaqi; Pan, Lina] Ausnutria Dairy China Co Ltd, Ausnutria Inst Food & Nutr, Changsha 410000, Peoples R China.;[Wu, Zhongkun; Kang, Wenli; Dai, Zhiyong; Wang, Jiaqi; Pan, Lina] Hunan Engn Res Ctr Human Microecol Prod, Changsha 410000, Peoples R China.
通讯机构：
[Lingyan Zhao; Fangming Deng] A;Authors to whom correspondence should be addressed.<&wdkj&>College of Food Science and Technology, Hunan Agricultural University, Changsha 410000, China
关键词：
Capsicum annuum L. Var. Dactylus M;fungal diversity;volatile favor compounds;correlation analysis
摘要：
Microbial diversity and dynamic changes play an important role in the production of fermented peppers. In this study, the relationship between fungal communities and the volatile flavor compounds of traditional Chinese fermented peppers was investigated by high-throughput sequencing technology. The results showed that Hanseniaspora was a dominant fungus during the whole fermentation course and accounted for 82.22% of the fungal community on average (ranging from 50.44% to 98.15%). Bidirectional orthogonal partial least squares (O2PLS) analysis between fungal community and volatile flavor compounds showed that Pichia, Hanseniaspora, Cryptococcus, Debarvomvces, and Trichosporon were closely correlated with the concentrations of the volatile flavor components such as alpha-terpineol, trans-3-tetradecene, 4-methylpentyl 3-methylbutanoate, and 11 other volatile flavor compounds. This study elucidated the dynamics of fungal communities and volatile flavor compounds during pepper fermentation and the correlation between them. Our analysis of the relationships between fungal communities and volatile flavor compounds advanced our understanding of the formation mechanism of volatile flavor compounds in fermented peppers.
摘要：
Liuyang Douchi is a kind of traditional fermented Aspergillus-type Douchi in China for excellent favor. However, studies on the microbial diversity and the characterization of predominate fungi of Liuyang Douchi are few. In present study, the Illumina HiSeq sequencing was performed to reveal the fluctuation characteristics of microbial diversity during fermentation. Results showed that Staphylococcus (33.86%), Staphylococcaceae_unclassified (27.39%) and Pediococcus (8.80%) were the dominated bacteria, while Petromyces (74.57%), Rhizopus (10.93%) and Penicillium (2.68%) were the most predominant fungi during entire fermentation period. Intriguingly, Petromyces was negatively correlated with Alternaria, Saccharomyces and Saccharomycetales_unclassified. Further, four non-aflatoxigenic Aspergillus flavus strains were first identified and isolated from Liuyang Douchi according to phylogenetic and macroscopic characteristics. These four Aspergillus flavus displayed high cellulase and protease activities, but weak lipase activity. This study could contribute to the quality control of Liuyang Douchi by providing an overview of the microbial diversity.
通讯机构：
[Liu, Shi Gang] L;Laboratory of Micro & Nano Biosensing Technology in Food Safety, Hunan Provincial Key Laboratory of Food Science and Biotechnology, College of Food Science and Technology, Hunan Agricultural University, Changsha, 410128, China.
通讯机构：
[Mingzhi Zhu; Zhonghua Liu] K;[Yuanliang Wang] C;Key Laboratory of Ministry of Education for Tea Science, College of Horticulture, Hunan Agricultural University, Changsha, 410128, China<&wdkj&>National Research Center of Engineering Technology for Utilization of Botanical Functional Ingredients, Hunan Agricultural University, Changsha, 410128, China<&wdkj&>College of Food Science and Technology, Hunan Agricultural University, Changsha, 410128, China<&wdkj&>Hunan Province Key Laboratory of Food Science and Biotechnology, Changsha, 410128, China<&wdkj&>Key Laboratory of Ministry of Education for Tea Science, College of Horticulture, Hunan Agricultural University, Changsha, 410128, China<&wdkj&>National Research Center of Engineering Technology for Utilization of Botanical Functional Ingredients, Hunan Agricultural University, Changsha, 410128, China
摘要：
Eurotium cristatum is the dominant fungus during Fu brick tea (FBT) manufacturing, however, its underlying effects in forming the distinct flavor characteristics of FBT remains unclear. In this work, effect of solid-stage fermentation (SSF) with E. cristatum on the volatile metabolites of dark teas was investigated by various tech-niques. A total of 54 and 93 volatile organic compounds (VOCs) were identified by HS-GC-IMS and HS-SPME-GC-MS, respectively, which are mainly composed of aldehydes, esters, alcohols and ketones. E. cristatum drastically affected the aroma characteristics of dark teas, and the middle fermentation stage showed the greatest influence. E. cristatum fermentation contributed to increasing the levels of VOCs with stale and flower aromas. Sensory evaluation revealed the intensities of green aroma greatly decreased, and replaced by flower, mint, woody and fungal flower aromas as fermentation progressed. Hydrolytic enzymes were secreted by E. cristatum that catalyze a series of biochemical reactions contributing to the formation of flavor metabolites. Thus, this study indicates that E. cristatum remarkably affected the VOCs of dark teas and improved the stale and flower aromas, which is crucial in forming characteristic volatile metabolites of FBT.
通讯机构：
[Shenghua Ding] L;[Rongrong Wang] C;Longping Branch, College of Biology, Hunan University, Changsha 410125, China<&wdkj&>Hunan Agricultural Product Processing Institute, Hunan Academy of Agricultural Sciences, Changsha 410125, China<&wdkj&>College of Food Science and Technology, Hunan Agricultural University, Changsha 410128, China
摘要：
The cuticle plays an important role for the quality of pepper fruit. However, the molecular mechanism of cuticle formation in pepper fruit remains unclear. Our results showed that the wax was continuously accumulated during pepper development, while the cutin monomer first increased and then decreased. Hexadecanoic acid and 10,16-hydroxyhexadecanoic acid were the main components of wax and cutin, respectively. Combined with transcriptome and proteome, the formation patterns of wax and cutin polyester network for pepper cuticle was proposed. The 18 pairs of consistent expression genes and proteins involved in cuticle formation were revealed. Meanwhile, 12 key genes were screened from fatty acid biosynthesis, biosynthesis of unsaturated fatty acids, fatty acid elongation, cutin, suberine, and wax biosynthesis, glycerolipid metabolism, and transport pathway. This study would provide important candidate genes and theoretical basis for the molecular mechanism of cuticle formation, which is essential for the breeding of peppers.
通讯机构：
[Jie Luo] K;Key Laboratory of Functional Dairy, Co-constructed by Ministry of Education and Beijing Government, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China<&wdkj&>College of Food Science and Technology, Hunan Agricultural University, Changsha 410114, China
摘要：
The regiodistribution of fatty acids (FAs) in triacylglycerols plays a critical role in the digestion and adsorption of milk lipids. However, the stereospecific location of FAs in yak milk triacylglycerols remains unknown. In this study, the intrapositional and interpositional distribution of FAs in the yak milk from different pastoral areas were compared with those of human milk and cow milk. When compared with human milk, the stereospecific locations of FAs were relatively similar between yak milk and cow milk. However, White yak milk and human milk contained similar interpositional proportions of linoleic, alinolenic acid and polyunsaturated FAs at the sn-3 position, significantly higher than those of cow milk. Moreover, the sn-3 interpositional proportion of a-linolenic acid in Maiwa yak milk was even higher than that in human milk. The study suggests that yak milk might provide better nutritional benefits as a source of essential FAs than cow milk. (C) 2021 Elsevier Ltd. All rights reserved.
