The aim of this research was to explore the effect of fixation,rolling,and drying processing technology on the retention rate of green tea catechins components and tea polyphenol.Different fixation processes(rotary dr...The aim of this research was to explore the effect of fixation,rolling,and drying processing technology on the retention rate of green tea catechins components and tea polyphenol.Different fixation processes(rotary drumfiring,microwave,steam-blasting),rolling process(weight of rolling,gently press rolling and traditional rolling),drying process(stove drying,roasting dehydration,baked fried drying) were adopted.The effect of different tea processing technology on the retention rate of catechins component and tea polyphenol was analyzed.It showed that the microwave fixation process,gently press rolling process,baked fried dry process were beneficial to keep high levels of EGCG,C,EGC,EC,ECG.展开更多
Tea polyphenols is a natural antioxidant with a variety of biological activity.However,the weak liposolubility and low bioavailability limit their application.As a result,structural modification of tea polyphenols com...Tea polyphenols is a natural antioxidant with a variety of biological activity.However,the weak liposolubility and low bioavailability limit their application.As a result,structural modification of tea polyphenols comes into being.The prepared liposoluble tea polyphenols was suggested as a good candidate antioxidant for edible-oil and fats products.But,safety studies on liposoluble tea polyphenols are limited.The objective of the present study was conducted to synthesize liposoluble tea polyphenols and evaluate its toxicity in Sprague-Dawley rats on oral administration at dietary levels of 1,2 and 4% for 30 days.There were no adverse effects on general condition,growth,food intake,feed conversion efficiency,haematology parameters,clinical chemistry values and organ weights.High-dose males exhibited a higher haemoglobin concentration and a lower alanine aminotransferase levels,and high-dose females showed a lower albumin and globulin levels.These slight changes were considered of no toxicological significance.Necropsy and histopathology findings revealed no treatment-related changes in any of the organs.Thus,the results allowed us to conclude that the liposoluble tea polyphenols properly utilized in the oral administration could be devoid of any toxic risk.展开更多
Stability of tea catechins and the antioxidant properties of green tea extracts as affected by boiling-treatment from 1 to 5h were studied.Green tea catechins were partially epimerized from epi-form to nonepi-form und...Stability of tea catechins and the antioxidant properties of green tea extracts as affected by boiling-treatment from 1 to 5h were studied.Green tea catechins were partially epimerized from epi-form to nonepi-form under boiling-treatment.Total phenolic compounds of the samples under the boiling-treatment for 1 to 4h showed the same statistically significant(P > 0.05) comparing with the untreated samples and there was no significant reduction(P > 0.05) of total catechins when the green tea extracts were boiling-treated for 1h.There were no significant(P > 0.05) reduction of the antioxidant capacity when the samples were boiling-treated for 1h,no significant(P> 0.05) reduction of the scavenging ability against DPPH and O-·2when treated for 2h,and no difference on scavenging ability against OH when treated even for 5h.The results indicated that boiling-treatment for 1h had limited effect on total catehins and phenols content in green tea extracts.Green tea extracts still remained excellent in antioxidant properties and free radical scavenging activity after boiling-treated for 1 h.展开更多
茶多酚是一类从茶叶中提取的多酚类物质的总称,在医药、食品和农业等领域具有广阔的应用前景。基于CNKI和WOS数据库,采用文献计量学方法,应用CiteSpace和VOSviewer软件对1953-2023年茶多酚研究论文进行数据挖掘和定量分析。结果表明:①7...茶多酚是一类从茶叶中提取的多酚类物质的总称,在医药、食品和农业等领域具有广阔的应用前景。基于CNKI和WOS数据库,采用文献计量学方法,应用CiteSpace和VOSviewer软件对1953-2023年茶多酚研究论文进行数据挖掘和定量分析。结果表明:①70年来,CNKI和WOS数据库中茶多酚研究论文数量均呈逐渐增长趋势。CNKI数据库中,论文主要发表在《福建茶叶》《食品工业科技》《食品科学》等期刊上,轻工业手工业学科的发文最多,基金资助以国家自然科学基金、国家科技支撑计划、国家重点研发计划等为主;WOS数据库中,论文主要发表在Journal of Agricultural and Food Chemistry、Food Chemistry、International Journal of Biological Macromolecules等期刊上,属于Food Science Technology学科的发文最多,基金资助以National Natural Science Foundation of China、United States Department of Health and Human Services、National Institutes of Health等为主;②从国家间的合作来看,中国发文量最大,同United States以及Philippines、Sri Lanka、Singapore等亚洲国家合作研究紧密,与India合作较少;③CNKI数据库中,浙江大学、江南大学、西南大学等是主要的研究机构,杨贤强、王岳飞、沈生荣等团队是国内主要的研究团队,国内研究涉及茶多酚的提取、抗氧化特性及其药理活性等方面;WOS数据库中,Rutgers University Systerm、Chinese Academy of Sciences、Zhejiang University等是主要的研究机构,Hara Y和Mukhtar H是主要的研究团队,国际研究更加关注茶多酚在医疗健康领域中的应用;④CNKI数据库中,“抗氧化”“壳聚糖”“保鲜”等是出现频率较高的关键词,茶多酚在食品领域中的应用是国内研究的前沿领域;WOS数据库中,关键词“catechins”“epigallocatechin gallate”“inhibition”等出现频率较高,国际研究前沿聚焦茶多酚与人体健康间的互作关系。通过文献综合分析可以帮助科研人员掌握该领域的研究现状和热点动态,明确未来研究方向。展开更多
旨在通过饲喂氧化鱼油(oxidized fish oil,OFO)饲粮在大鼠上建立动物营养性氧化应激模型,探讨灌服茶褐素(theabrownin,TB)能否改善氧化应激对大鼠肝的负面影响,并初步分析其可能机制;且以茶多酚(tea polyphenols,TP)为正对照。试验选取3...旨在通过饲喂氧化鱼油(oxidized fish oil,OFO)饲粮在大鼠上建立动物营养性氧化应激模型,探讨灌服茶褐素(theabrownin,TB)能否改善氧化应激对大鼠肝的负面影响,并初步分析其可能机制;且以茶多酚(tea polyphenols,TP)为正对照。试验选取32只健康的21日龄断奶的Wistar大鼠(雄性),平均体重(BW)为55.58 g,随机分为4个处理(n=8),即对照组、OFO组、OFO+TP组和OFO+TB组,TP和TB的灌服剂量均为200 mg·kg^(-1)BW,含OFO饲粮从试验第9天开始饲喂,整个试验持续23 d。结果显示:饲喂含OFO饲粮降低了大鼠的体重,诱导大鼠肝发生病理变化,显著提高了肝的脏器指数及血清丙氨酸氨基转移酶活性(P<0.05),显著降低了肝的总抗氧化能力及过氧化氢酶和谷胱甘肽过氧化物酶活性(P<0.05),显著提高了肝中脂质过氧化物、丙二醛、蛋白质羰基和8-羟基脱氧鸟苷含量(P<0.05),显著上调了Bax、Caspase3和Keap-1的mRNA表达水平(P<0.05),显著下调了Bcl-2、Nrf2、HO-1和NQO-1的mRNA表达水平(P<0.05);灌服TB或TP可以在不同程度上缓解OFO攻毒对大鼠的体重及肝的结构和功能的负面影响,提高了饲喂氧化鱼油饲粮大鼠肝的抗氧化能力(P<0.05),改善了饲喂氧化鱼油饲粮大鼠肝中细胞凋亡和Nrf2信号通路相关基因mRNA表达(P<0.05)。综上可知,灌服TB能改善OFO攻毒大鼠的肝损伤,这可能与其改善抗氧化功能和细胞凋亡有关,且TB的作用效果类似于TP。展开更多
文摘The aim of this research was to explore the effect of fixation,rolling,and drying processing technology on the retention rate of green tea catechins components and tea polyphenol.Different fixation processes(rotary drumfiring,microwave,steam-blasting),rolling process(weight of rolling,gently press rolling and traditional rolling),drying process(stove drying,roasting dehydration,baked fried drying) were adopted.The effect of different tea processing technology on the retention rate of catechins component and tea polyphenol was analyzed.It showed that the microwave fixation process,gently press rolling process,baked fried dry process were beneficial to keep high levels of EGCG,C,EGC,EC,ECG.
基金Project of the National Twelfth-Five Year Research Program of China(2012BAD36B06)
文摘Tea polyphenols is a natural antioxidant with a variety of biological activity.However,the weak liposolubility and low bioavailability limit their application.As a result,structural modification of tea polyphenols comes into being.The prepared liposoluble tea polyphenols was suggested as a good candidate antioxidant for edible-oil and fats products.But,safety studies on liposoluble tea polyphenols are limited.The objective of the present study was conducted to synthesize liposoluble tea polyphenols and evaluate its toxicity in Sprague-Dawley rats on oral administration at dietary levels of 1,2 and 4% for 30 days.There were no adverse effects on general condition,growth,food intake,feed conversion efficiency,haematology parameters,clinical chemistry values and organ weights.High-dose males exhibited a higher haemoglobin concentration and a lower alanine aminotransferase levels,and high-dose females showed a lower albumin and globulin levels.These slight changes were considered of no toxicological significance.Necropsy and histopathology findings revealed no treatment-related changes in any of the organs.Thus,the results allowed us to conclude that the liposoluble tea polyphenols properly utilized in the oral administration could be devoid of any toxic risk.
文摘Stability of tea catechins and the antioxidant properties of green tea extracts as affected by boiling-treatment from 1 to 5h were studied.Green tea catechins were partially epimerized from epi-form to nonepi-form under boiling-treatment.Total phenolic compounds of the samples under the boiling-treatment for 1 to 4h showed the same statistically significant(P > 0.05) comparing with the untreated samples and there was no significant reduction(P > 0.05) of total catechins when the green tea extracts were boiling-treated for 1h.There were no significant(P > 0.05) reduction of the antioxidant capacity when the samples were boiling-treated for 1h,no significant(P> 0.05) reduction of the scavenging ability against DPPH and O-·2when treated for 2h,and no difference on scavenging ability against OH when treated even for 5h.The results indicated that boiling-treatment for 1h had limited effect on total catehins and phenols content in green tea extracts.Green tea extracts still remained excellent in antioxidant properties and free radical scavenging activity after boiling-treated for 1 h.
文摘茶多酚是一类从茶叶中提取的多酚类物质的总称,在医药、食品和农业等领域具有广阔的应用前景。基于CNKI和WOS数据库,采用文献计量学方法,应用CiteSpace和VOSviewer软件对1953-2023年茶多酚研究论文进行数据挖掘和定量分析。结果表明:①70年来,CNKI和WOS数据库中茶多酚研究论文数量均呈逐渐增长趋势。CNKI数据库中,论文主要发表在《福建茶叶》《食品工业科技》《食品科学》等期刊上,轻工业手工业学科的发文最多,基金资助以国家自然科学基金、国家科技支撑计划、国家重点研发计划等为主;WOS数据库中,论文主要发表在Journal of Agricultural and Food Chemistry、Food Chemistry、International Journal of Biological Macromolecules等期刊上,属于Food Science Technology学科的发文最多,基金资助以National Natural Science Foundation of China、United States Department of Health and Human Services、National Institutes of Health等为主;②从国家间的合作来看,中国发文量最大,同United States以及Philippines、Sri Lanka、Singapore等亚洲国家合作研究紧密,与India合作较少;③CNKI数据库中,浙江大学、江南大学、西南大学等是主要的研究机构,杨贤强、王岳飞、沈生荣等团队是国内主要的研究团队,国内研究涉及茶多酚的提取、抗氧化特性及其药理活性等方面;WOS数据库中,Rutgers University Systerm、Chinese Academy of Sciences、Zhejiang University等是主要的研究机构,Hara Y和Mukhtar H是主要的研究团队,国际研究更加关注茶多酚在医疗健康领域中的应用;④CNKI数据库中,“抗氧化”“壳聚糖”“保鲜”等是出现频率较高的关键词,茶多酚在食品领域中的应用是国内研究的前沿领域;WOS数据库中,关键词“catechins”“epigallocatechin gallate”“inhibition”等出现频率较高,国际研究前沿聚焦茶多酚与人体健康间的互作关系。通过文献综合分析可以帮助科研人员掌握该领域的研究现状和热点动态,明确未来研究方向。
