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茶儿茶素稳定血糖作用及机理研究进展

食品科学 2024年第10期45卷 330-341页

作者：汪凌辉许娜杨倩楠黄进宝王一君宛晓春安徽农业大学茶与食品科技学院安徽合肥230036 安徽农业大学茶树生物学与资源利用国家重点实验室安徽合肥230036

随着现代社会饮食结构的变化,糖尿病及其并发症已成为全球关注的公共卫生问题,中国患病总人数已位居世界第一。现代科学证明茶叶是降血糖天然多酚的重要来源,作为健康饮品在糖尿病膳食治疗中发挥重要作用。儿茶素是茶叶中关键功能物质,... 详细信息

随着现代社会饮食结构的变化,糖尿病及其并发症已成为全球关注的公共卫生问题,中国患病总人数已位居世界第一。现代科学证明茶叶是降血糖天然多酚的重要来源,作为健康饮品在糖尿病膳食治疗中发挥重要作用。儿茶素是茶叶中关键功能物质,能够通过抑制外源碳水化合物水解、调控葡萄糖转移、促进葡萄糖氧化分解、抑制糖异生过程、调控糖原合成及分解过程、促进胰岛素分泌、改善胰岛素抵抗、改善氧化应激状态等不同途径有效调节血糖水平。本文在总结国内外有关儿茶素对肥胖、糖尿病及代谢综合症作用研究的基础上,梳理了儿茶素稳定血糖生理机制的研究进展,旨在为儿茶素的精准化开发提供理论依据及应用参考。

关键词：茶儿茶素血糖糖代谢糖尿病胰岛素抵抗

Efficient iron plaque formation on tea(Camellia sinensis) roots contributes to acidic stress tolerance

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Journal of Integrative Plant Biology 2019年第2期61卷 155-167页

作者： Xianchen Zhang Honghong Wu Lingmu Chen Yeyun Li xiaochun wan State Key Laboratory of Tea Plant Biology and Utilization Anhui Agricultural University Department of Botany and Plant Sciences University of California

Tea plants grow in acidic soil, but to date, their intrinsic mechanisms of acidic stress tolerance have not been elucidated. Here, we assessed the tea plant response to growth on NHt4 nutrient media having different p H and iron levels. When grown in standard NHt4 nutrient solution(iron insufficient, 0.35 mg Là1 Fe2t), tea roots exhibited significantly lower nitrogen accumulation, plasma membrane Ht-ATPase activity, and protein levels; net Htefflux was lower at pH 4.0 and 5.0 than at pH 6.0. Addition of30 mg Là1 Fe2t(iron sufficient, mimicking normal soil Fe2tconcentrations) to the NHt4 nutrient solution led to more efficient iron plaque formation on roots and increased root plasma membrane Ht-ATPase levels and activities at p H 4.0 eland 5.0, compared to the p H 6.0 condition. Furthermore,plants grown at pH 4.0 and 5.0, with sufficient iron,exhibited significantly higher nitrogen accumulation than those grown at pH 6.0. Together, these results support the hypothesis that efficient iron plaque formation, on tea roots, is important for acidic stress tolerance. Furthermore,our findings establish that efficient iron plaque formation is linked to increased levels and activities of the tea root plasma membrane Ht-ATPase, under low pH conditions.

关键词： ATPase PM Efficient iron plaque formation on tea Figure Fe

Maintenance of mesophyll potassium and regulation of plasma membrane H^+-ATPase are associated with physiological responses of tea plants to drought and subsequent rehydration

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The Crop Journal 2018年第6期6卷 611-620页

作者： Xianchen Zhang Honghong Wu Linmu Chen Linlin Liu xiaochun wan State Key Laboratory of Tea Plant Biology and Utilization Anhui Agricultural University Department of Botany and Plant Sciences University of California

Drought stress is one of the main factors limiting yield in tea plants. The plant cell's ability to preserve K^+homeostasis is an important strategy for coping with drought stress. Plasma membrane H^+-ATPase in the mesophyll cell is important for maintaining membrane potential to regulate K^+transmembrane transport. However, no research to date has investigated the possible relationship between plasma membrane H^+-ATPase and mesophyll K^+retention in tea plants under drought and subsequent rehydration conditions. In our experiment, drought stress inhibited plasma membrane H^+-ATPase activities and induced net H^+influx, leading to membrane potential depolarization and inducing a massive K^+efflux in tea plant mesophyll cells. Subsequent rehydration increased plasma membrane H^+-ATPase activity and induced net H^+efflux, leading to membrane potential hyperpolarization and thus lowering K^+loss. A first downregulated and then upregulated plasma membrane H^+-ATPase protein expression level was also observed under drought and subsequent rehydration treatment, a finding in agreement with the change of measured plasma membrane H^+-ATPase activities. Taken together, our results suggest that maintenance of mesophyll K^+in tea plants under drought and rehydration is associated with regulation of plasma membrane H^+-ATPase activity.

关键词： Drought stress H^+-ATPase Membrane potential Potassium Rehydration

GOLDEN 2-LIKE transcription factors regulate chlorophyll biosynthesis and flavonoid accumulation in response to UV-B in tea plants

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Horticultural Plant Journal(园艺学报:英文版) 2023年第5期9卷 1055-1066页

作者： Xuyang Liu Xin Cheng Jingjie Cao Wenfeng Zhu xiaochun wan Linlin Liu State Key Laboratory of Tea Plant Biology and Utilization Key Laboratory of Tea Biology and Tea Processing of Ministry of AgricultureAnhui Provincial Laboratory of Tea Plant Biology and UtilizationAnhui Agricultural UniversityHefeiAnhui 230036China

Flavonoids are critical secondary metabolites that determine the health benefits and flavor of tea,while chlorophylls are important contributors to the appearance of ***,transcription factors(TFs)that can integrate both chlorophyll biosynthesis and flavonoid accumulation in response to specific light signals are rarely *** this study,we report that the GOLDEN 2-LIKE TF pair,CsGLK1 and CsGLK2,orchestrate UV-B-induced responses in the chlorophyll biosynthesis and flavonoid accumulation of tea *** absence of solar UV-B reduced the transcriptional expression of CsGLKs in the tea leaves and was highly correlated with a decrease in flavonoid levels(especially flavonol glycosides)and the expression of genes and TFs involved in chlorophyll biosynthesis and flavonoid *** vivo and in vitro molecular analyses showed that CsGLKs could be regulated by the UV-B signal mediator CsHY5,and could directly bind to the promoters of gene and TF involved in light-harvesting(CsLhcb),chlorophyll biosynthesis(CsCHLH,CsHEMA1,and CsPORA),and flavonoid accumulation(CsMYB12,CsFLSa,CsDFRa,and CsLARa),eventually leading to UV-B-induced responses in the chlorophylls and flavonoids of tea ***,UV-B exposure increased the levels of total flavonoids,CsGLK1 protein,and expression of CsGLKs and target genes in the tea *** results indicate that CsGLKs may modulate tea leaf characteristics by regulating chlorophyll biosynthesis and flavonoid accumulation in response to solar *** the first report on UV-B-induced changes in flavonoid and chlorophyll regulation mediated by CsGLKs,this study improves our understanding of the environmental regulations regarding tea quality and sheds new light on UV-B-induced flavonoid responses in higher plants.

关键词： Camellia sinensis GLK Flavonoid Chlorophyll UV-B

基于分子感官组学的不同产区茉莉花茶香气组成特征分析

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安徽农业大学学报 2024年第3期51卷 495-502页

作者：周丽伟史乐怡宁井铭宛晓春安徽农业大学茶树生物学与资源利用国家重点实验室合肥230036

为探明不同产区茉莉花茶香气特征的品质属性,采用顶空固相微萃取(HS-SPME)结合气相色谱-质谱(GC-MS)联用技术对四大主产区(福建、广西、云南和四川)茉莉花茶挥发性成分进行检测与分析。从4个产地茉莉花茶中共鉴定出145种挥发性化合物,... 详细信息

为探明不同产区茉莉花茶香气特征的品质属性,采用顶空固相微萃取(HS-SPME)结合气相色谱-质谱(GC-MS)联用技术对四大主产区(福建、广西、云南和四川)茉莉花茶挥发性成分进行检测与分析。从4个产地茉莉花茶中共鉴定出145种挥发性化合物,其中在119种共有挥发性物质中,芳樟醇、乙酸苄酯、苯甲酸甲酯、乙酸叶醇酯、顺-3-苯甲酸叶醇酯、水杨酸甲酯、吲哚、邻氨基苯甲酸甲酯、苯甲醇、(Z)-3-己烯-1-醇等10种化合物是四大主产区茉莉花茶主要挥发性成分,但不同产地间的茉莉花茶香气品质仍存在一定的差异。多元统计分析筛选出26种重要差异化合物,其中,1,1-二乙氧基己烷、(Z)-3-己烯-1-醇、1-辛烯-3-醇、戊醛、正己醛等11种青草气化合物在四川茉莉花茶中相对含量较高。苯甲酸苄酯、顺-茉莉酮、α-法呢稀、香叶醇等9种花香化合物在广西茉莉花茶中相对含量较高。结合相对香气活度值法(r OAV,relativearomaactivityvalue)、气相色谱-嗅觉测量法(GC-O,gas chromatography-olfactometry)和香气提取物稀释分析(AEDA,aroma extract dilution analysis)对茉莉花茶的特征香气物质分析,经过香气重组发现,芳樟醇、邻氨基苯甲酸甲酯、乙酸苄酯、吲哚、苯甲酸甲酯、(Z)-4-庚烯醛、水杨酸甲酯、β-紫罗酮和乙酸叶醇酯等9种香气活性物质被确定为茉莉花茶香气特征物质。该研究结果为茉莉花茶香气标准的制定提供参考依据。

关键词：茉莉花茶特征香气气相色谱-质谱联用技术气相色谱嗅闻仪相对香气活度值香气重组

Focusing on the recent progress of tea polyphenol chemistry and perspectives

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Food Science and Human Wellness 2022年第3期11卷 437-444页

作者： Shiming Li Liang Zhang xiaochun wan Jianfeng Zhan Chi-Tang Ho Hubei Key Laboratory of EFGIR Huanggang Normal UniversityHuanggang 438000China State Key Laboratory of Tea Plant Biology and Utilization School of Tea&Food ScienceAnhui Agricultural UniversityHefei 230036China Department of Food Science Rutgers UniversityNJ 08901USA

Myriad evidence attests to the health-promoting benefits of tea *** there are multiple factors of tea influencing the effective biological properties,tea polyphenols are the most significant and valuable *** chemical characterization and physical characteristics of tea polyphenols have been comprehensively studied over the previous *** the emergence of new chemistry in tea,particularly the property of scavenging reactive carbonyl species(RCS)and the newly discovered flavoalkaloid compounds,has drawn increasing *** this review,we summarize recent findings of a new class of compounds in tea-flavonoid alkaloids(flavoalkaloids),which exist in fresh tea leaves and can be generated during the process of post-harvesting,and also postulate the formation mechanism of flavoalkaloids between catechins and theanine-derived Strecker ***,we detail the up-to-date research results of tea polyphenols regarding their ability to trap RCS and their in vivo aminated metabolites to suppress advanced glycation ends products(AGEs).We further raise questions to be addressed in the near future,including the synthetic pathways for the generation of flavoalkaloids and AGEs in fresh tea leaves before processing and the concentrations of tea polyphenols that affect their RCS scavenging capability due to their pro-oxidant *** intensive research is warranted to elucidate the mechanisms of action underlying the biological activity of flavoalkaloids and the pharmacological application of tea polyphenols in scavenging RCS and impeding detrimental AGEs.

关键词： Tea chemistry Flavonoalkaloids RCS adducts Aminated tea polyphenols AGEs

UGT74AF3 enzymes specifically catalyze the glucosylation of 4-hydroxy-2,5-dimethylfuran-3(2H)-one,an important volatile compound in Camellia sinensis

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Horticulture Research 2020年第1期7卷 2433-2443页

作者： Yongxian Chen Xiangyang Guo Ting Gao Na Zhang xiaochun wan Wilfried Schwab Chuankui Song State Key Laboratory of Tea Plant Biology and Utilization International Joint Laboratory on Tea Chemistry and Health EffectsAnhui Agricultural University230036 HefeiAnhuiP.R.China Biotechnology of Natural Products Technische Universität MünchenLiesel-Beckmann-Str.185354 FreisingGermany

4-Hydroxy-2,5-dimethylfuran-3(2H)-one(HDMF)is an important odorant in some fruits,and is proposed to play a crucial role in the caramel-like notes of some ***,its biosynthesis and metabolism in tea plants are still ***,HDMF glucoside was unambiguously identified as a native metabolite in tea plants.A novel glucosyltransferase UGT74AF3a and its allelic protein UGT74AF3b specifically catalyzed the glucosylation of HDMF and the commercially important structural homologues 2(or 5)-ethyl-4-hydroxy-5(or 2)-methylfuran-3(2H)-one(EHMF)and 4-hydroxy-5-methylfuran-3(2H)-one(HMF)to their correspondingβ-***-directed mutagenesis of UGT74AF3b to introduce a single A456V mutation resulted in improved HDMF and EHMF glucosylation activity and affected the sugar donor preference compared with that of the wild-type control *** accumulation of HDMF glucoside was consistent with the transcript levels of UGT74AF3 in different tea *** addition,transient UGT74AF3a overexpression in tobacco significantly increased the HDMF glucoside contents,and downregulation of UGT74AF3 transcripts in tea leaves significantly reduced the concentration of HDMF glucoside compared with the levels in the *** identification of HDMF glucoside in the tea plant and the discovery of a novel-specific UDP-glucose:HDMF glucosyltransferase in tea plants provide the foundation for improvement of tea flavor and the biotechnological production of HDMF glucoside.

关键词： metabolism volatile sugar

COVID-19:immunopathogenesis and Immunotherapeutics

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Signal Transduction and Targeted Therapy 2020年第1期5卷 1327-1334页

作者： Li Yang Shasha Liu Jinyan Liu Zhixin Zhang xiaochun wan Bo Huang Youhai Chen Yi Zhang Biotherapy Center The First Affiliated Hospital of Zhengzhou University450052 ZhengzhouChina Institute of Health Management Health Management CenterSichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of China611731 ChengduChina Shenzhen Laboratory of Human Antibody Engineering Institute of Biomedicine and BiotechnologyShenzhen Institutes of Advanced TechnologyChinese Academy of Sciences518055 ShenzhenChina Department of Immunology&National Key Laboratory of Medical Molecular Biology Institute of Basic Medical SciencesChinese Academy of Medical Sciences(CAMS)&Peking Union Medical College100005 BeijingChina Department of Pathology and Laboratory Medicine School of MedicineUniversity of PennsylvaniaPhiladelphiaPA 19104USA

The recent novel coronavirus disease(COVID-19)outbreak,caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),is seeing a rapid increase in infected patients *** host immune response to SARS-CoV-2 appears to play a critical role in disease pathogenesis and clinical ***-CoV-2 not only activates antiviral immune responses,but can also cause uncontrolled inflammatory responses characterized by marked pro-inflammatory cytokine release in patients with severe COVID-19,leading to lymphopenia,lymphocyte dysfunction,and granulocyte and monocyte *** SARS-CoV-2-induced immune abnormalities may lead to infections by microorganisms,septic shock,and severe multiple organ ***,mechanisms underlying immune abnormalities in patients with COVID-19 must be elucidated to guide clinical management of the ***,rational management of the immune responses to SARSCoV-2,which includes enhancing anti-viral immunity while inhibiting systemic inflammation,may be key to successful *** this review,we discuss the immunopathology of COVID-19,its potential mechanisms,and clinical implications to aid the development of new therapeutic strategies against COVID-19.

关键词： pathogenesis immunity clinical

Haem Oxygenase 1 is a potential target for creating etiolated/albino tea plants (Camellia sinensis) with high theanine accumulation

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Horticulture Research 2023年第2期10卷 194-202页

作者： Ziping Chen Shijia Lin Tingting Chen Mengxue Han Tianyuan Yang Yan wang Shilai Bao Zhougao Shen xiaochun wan Zhaoliang Zhang State Key Laboratory of Tea Plant Biology and Utilization Anhui Agricultural UniversityHefei230036China Anhui Promotion Center for Technology Achievements Transfer Anhui Academy of Science and TechnologyHefei230031China State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing100101China School of Life Sciences University of Chinese Academy of SciencesBeijing100049China

Theanine content is highly correlated with sensory quality and health benefits of tea *** tender shoots of etiolated and albino tea plants contain higher theanine than the normal green tea plants and are valuable materials for high quality green tea ***,why these etiolated or albino tea plants can highly accumulate theanine is largely *** this study,we observed an Arabidopsis etiolated mutant hy1–100(mutation in Haem Oxygenase 1,HO1)that accumulated higher levels of glutamine(an analog of theanine).We therefore identified CsHO1 in tea plants and found CsHO1 is conserved in amino acid sequences and subcellular localization with its homologs in other ***,CsHO1 expression in the new shoots was much lower in an etiolated tea plants‘Huangkui’and an albino tea plant‘Huangshan Baicha’than that in normal green tea *** expression levels of CsHO1 were negatively correlated with theanine contents in these green,etiolated and albino ***,CsHO1 expression levels in various organs and different time points were also negatively correlated with theanine *** hy1–100 was hypersensitive to high levels of theanine and accumulated more theanine under theanine feeding,and these phenotypes were rescued by the expression of CsHO1 in this *** knockdown CsHO1 expression in the new shoots of tea plant using antisense oligonucleotides(asODN)increased theanine ***,these results demonstrated CsHO1 negatively regulates theanine accumulation in tea plants,and that low expression CsHO1 likely contributes to the theanine accumulation in etiolated/albino tea plants.

关键词： organs Oxygen high