Antioxidant and anti-inflammatory roles of tea polyphenols in inflammatory bowel diseases

Polyphenols,including phenolic acids,flavonoids,and procyanidins,are abundant in food and beverage derived from plants.Tea(Camellia sinensis)is particularly rich in polyphenols(e.g.,catechins,theaflavins,thearubigins,gallic acid,and flavonols),which are thought to contribute to the health benefits of tea.High intake of tea polyphenols has been described to prevent and/or attenuate a variety of chronic pathological conditions like cardiovascular diseases,neurodegenerative diseases,diabetes,and cancer.This review focuses on established antioxidant and anti-inflammatory properties of tea polyphenols and underlying mechanisms of their involvement in inflammatory bowel diseases(IBD).Tea polyphenols act as efficient antioxidants by inducing an endogenous antioxidant defense system and maintaining intracellular redox homeostasis.Tea polyphenols also regulate signaling pathways such as nuclear factor-κB,activator protein 1,signal transducer and activator of transcriptions,and nuclear factor E2-related factor 2,which are associated with IBD development.Accumulating pieces of evidence have indicated that tea polyphenols enhance epithelial barrier function and improve gut microbial dysbiosis,contributing to the management of inflammatory colitis.Therefore,this study suggests that supplementation of tea polyphenols could prevent inflammatory conditions and improve the outcome of patients with IBD.

Effect of Tea Polyphenols and Vitamin E on Antioxidant Performance in Broilers

[ Objedlve] To investigate the effects of tea polyphenols （TP） and vitamin E （VE ） on growth performance and antioxidant performance of broilers in the routine breeding conditions. [ Method] A total of 270 broilers at 1 day old were fed on the basic diets supplemented with TP and VE at different proportions. The malondialdehyde （MDA） content, total antioxidant capacity （T-AOC） as well as activities of superoxide dismutase （SOD） and glutathione peroxidase （GSH-Px） were measured. The whole weight gain and feed conversion rate were also determined. [ Result] The broilers fed on TP and VE had remarkably higher serum activities of SOD and GSH-Px, stronger T-AOC and lower MDA content than the control ones. The best effects were achieved when the supplementary dosage of -rP and VE was respectively 60 and 80 mg/kg · Diet, because the experi- mental broilers had significantly higher antioxidant indices than the control ones （ P 〈 0.01 ）. Additionally, the boilers at the age of 21 or 42 days old had significantly higher body weight and lower feed conversion rate than the control ones （ P 〈 0.01 ）. [ Conclusion] The study provides a theoreti- cal basis for the applications of TP and VE in animal production.

Studies on Human Fetal Lens Crystallins Under Oxidative Stress and Protective Effects of Tea Polyphenols

Purpose: To investigate the oxidative modification of water-soluble crystallins of human fetal lens with H2O2 and fourteen metal ions with or without EDTA. Tea-polyphenols (TP) was added to above solutions in order to testing their antioxidative abilities. Methods: The experiments were performed at 37℃ with final concentration of 2.5mg/ml protein, 0.1 mM metal ions, 0.3 mM EDTA and 1.0 mM H2O2. Then the TP was added to the solution with CuSO4 and H2O2, after 5 or 24 hours, the crystallins were analysed with SDS-PAGE and IEF.Results : There were marked oxidative modifications of lens protein in H2O2 and copper without EDTA. In SDS-PAGE patterns, we found an increase in those species above of bands higher than 30 kD and some diffuse bands from 30 to 17 kD after 5 hours. In IEF patterns, there were a general increase on acidity with loss of the more basic species. When the TP was added, there was not any difference with control group.Conclusion: The results indicate that exposure of water-soluble

Changes in Polyphenols and Antioxidant Activities of Yingshan Yunwu Tea during Digestion in Vitro

[Objectives]To explore the change rule of polyphenol content and antioxidant activity of coarse old leaves of Yingshan Yunwu Tea in the process of human digestion.[Methods]The coarse and old leaves of Yunwu tea in Yingshan,Huanggang,Hubei Province were selected as the research object,and their digestion in vitro was simulated.The total polyphenol content was determined by Folin-phenol reagent colorimetric method,and the DPPH radical scavenging activity and total antioxidant activity were determined.[Results]After simulated gastrointestinal digestion in vitro,the polyphenol content and antioxidant activity of coarse old leaf tea soup showed a downward trend.After gastrointestinal digestion,the polyphenol content in tea infusion separately decreased by 31.8%and 8.5%;the scavenging rate of DPPH free radical was 97%before digestion,decreased to 92%after gastric digestion and 65%after intestinal digestion,which decreased by 5%and 27%,respectively;after gastrointestinal digestion,the total antioxidant capacity of tea soup decreased by 4.7%and 3.1%,respectively.[Conclusions]This study provided a reference for the development and application of coarse old leaves of Yingshan Yunwu tea,and provided a reference for the nutritional value evaluation and comprehensive utilization of coarse old leaves,so as to make the best use of coarse tea leaves and reduce the waste of resources.

Antioxidant mechanism of tea polyphenols and its impact on health benefits

Tea trees have a long history of cultivation and utilization.People in many countries have the habit of drinking tea and choosing green tea,oolong tea,or black tea according to different regions and personal tastes.Tea polyphe nols are a general term for polyphenol co mpounds in tea,and has been shown to have good effects on antioxidant,anti-inflammatory,cancer prevention and regulation of lipid metabolism.Tea polyphenols have been widely used as antioxidants in disease treatment and animal husbandry,but their specific mechanism of action needs to be further clarified and revealed.This review focuses on the definition,classification,antioxidant activity and the regulation of signaling pathways of tea polyphenols.This paper also aims to examine the application of tea polyphenols in human and animal health,providing a scientific basis for this application in addition to proposing future directions for the development of this resource.

Inhibition of free radical induced oxidative hemolysis of red blood cells by green tea polyphenols

The in vitro oxidative hemolysis of human red blood cells (RBC) was used as a model to study the free radical induced damage of biological membranes and the inhibitory effect of natural antioxidants. The hemolysis was induced by a water-soluble free radical initiator 2,2’-azo(2-asmidinopropane)dihydrochloride (AAPH) and inhibited by the principal polyphenolic components extracted from green tea leaves, i.e. (-)-epicatechin (EC), (-)-epigallocatechin (EGC), (-)-epicat-echin gallate (ECG), (-)-epigallocatechin gallate (EGCG) and gallic acid (GA). Addition of AAPH at 37℃ caused fast hemolysis after a short period of inhibition period, while addition of the green tea polyphenols efficiently suppressed the hemolysis in the activity sequence of EGCG 】 EGC】 ECG ≈EC】GA, demonstrating that these green tea polyphenols are effective antioxidants which could protect biological membranes from free radical induced oxidative damage.

Tea polyphenols increase the antioxidant status of laying hens fed diets with different levels of ageing corn

This study was conducted to evaluate the effects of ageing corn levels(stored for 4 years)with or without the supplementation of tea polyphenols(TPP)on the performance,egg quality and antioxidant status of laying hens.A total of 288 Lohmann commercial laying hens(63-week-old)were used under a 2×4 factorial arrangement with 4 levels of dietary ageing corn(0%,25%,50%,or 100%)and 2 levels of TPP(0 and 600 mg/kg)for 8 wk.Dietary ageing corn linearly decreased(P<0.05)the egg production,serum total antioxidant capacity(T-AOC),liver glutathione peroxidase(GSH-Px)of laying hens,yolk index,yolk colour,1,1-diphenyl-2-picrylhydrazyl(DPPH)value and the reducing power value of egg yolk,but it linearly increased(P<0.05)the feed conversion rate,ovary malondialdehyde(MDA)content of laying hens,and the protein carbonyl content of egg yolk.Tea polyphenol supplementation increased(P<0.05)the serum T-AOC,serum superoxide dismutase(SOD),liver SOD,liver GSH-Px,ovary SOD,GSH-Px,the expression of antioxidant-related genes of laying hens,albumen height,Haugh unit,DPPH value and the majority free amino acids of egg yolk,but it decreased(P<0.05)the serum MDA content of laying hens,MDA and protein carbonyl of egg yolk.In conclusion,the ageing corn significantly reduced the perfor-mance,egg quality,antioxidant status and egg antioxidant capacity of laying hens,while TPP supple-mentation partially counteracted the adverse effects,especially antioxidant status and egg antioxidant capacity of laying hens.

茶多酚的生物学功能及其在动物生产中的应用

茶多酚是茶叶中的主要成分。茶多酚是一类含有酚羟基结构的多元酚类混合物的总称,主要由黄酮类、花青素、酚酸及儿茶素类等物质组成,具有抗氧化、抗病毒、抗菌抑菌、调节糖脂代谢等生物学功能。茶多酚作为饲料添加剂,能够改善动物机体的免疫力、抗氧化功能,提高机体的抗病力,调节体内多种生理代谢功能,进而改善动物的生产性能,增加养殖利润。文章综述了茶多酚的理化性质、主要成分、生物学功能及其在动物生产中应用研究进展,为茶多酚在动物养殖生产中的高效利用提供参考。

茶多酚对0~18周龄狮头鹅生长性能、屠宰性能及肌肉品质的影响

本试验旨在探究饲粮中添加茶多酚对0~18周龄狮头鹅生长性能、屠宰性能、肌肉品质及抗氧化能力的影响。试验采用单因素完全随机试验设计,选取1日龄体重相近的健康雄性狮头鹅360只,随机分为3组,每组6个重复,每个重复20只鹅。对照组饲喂基础饲粮,试验Ⅰ和Ⅱ组分别在基础饲粮中添加500和1000 mg/kg茶多酚,试验期18周。结果表明:1)与对照组相比,各试验组13~18周龄料重比均显著降低(P<0.05)。2)与对照组相比,各试验组腹脂率均显著降低(P<0.05)。3)与对照组相比,各试验组胸肌24 h红度(a*)值、腿肌45 min a*值均显著提高(P<0.05),胸肌剪切力显著降低(P<0.05);试验Ⅱ组腿肌pH 45 min和pH 24 h显著提高(P<0.05),腿肌24 h亮度(L*)值和胸肌滴水损失显著降低(P<0.05)。4)与对照组相比,各试验组胸肌和腿肌粗灰分含量均显著降低(P<0.05),试验Ⅱ组胸肌水分含量显著降低(P<0.05)。5)与对照组相比,各试验组胸肌和腿肌中总超氧化物歧化酶(T-SOD)活性均显著提高(P<0.05),腿肌谷胱甘肽过氧化酶(GSH-Px)活性显著提高(P<0.05),胸肌丙二醛(MDA)含量显著降低(P<0.05);试验Ⅰ组胸肌总抗氧化能力(T-AOC)显著提高(P<0.05),试验Ⅱ组腿肌T-AOC显著提高(P<0.05)。综上所述,饲粮中添加茶多酚可提高狮头鹅饲料报酬,改善肉品质,降低腹脂率,并提高肌肉抗氧化能力。在本试验条件下,在0~18周龄狮头鹅饲粮中添加1000 mg/kg茶多酚的应用效果相对较优。

干燥方式对绿碎茶多酚提取物体外抗氧化和抗糖尿病及乙酰胆碱酯酶抑制活性的影响

研究不同干燥方式处理的绿碎茶多酚提取物体外抗氧化和抗糖尿病活性及对乙酰胆碱酯酶抑制作用。以绿碎茶为试验材料,采用蒸干结合真空干燥与真空冷冻干燥2种干燥工艺对绿碎茶乙酸乙酯萃取相进行干燥处理,比较研究了2种提取物的色泽,DPPH自由基、ABTS阳离子自由基、羟自由基(·OH)清除能力和铁离子还原能力以及α-淀粉酶、α-葡萄糖苷酶、乙酰胆碱酯酶的抑制能力和抗糖基化能力。结果表明,真空冷冻干燥绿碎茶多酚提取物(BGTE-FD)较蒸干结合真空干燥绿碎茶多酚提取物(BGTE-SVD)颜色相对偏黄,具有较强的DPPH自由基、ABTS阳离子自由基、·OH清除能力和铁离子还原能力,其IC_(50)值分别为2.64、5.17、247.01、27.73 mg/L。同时,BGTE-FD具有较高的α-淀粉酶、乙酰胆碱酯酶和α-葡萄糖苷酶抑制作用,IC_(50)值分别为85.84、416.45、4.38 mg/L,且其对α-葡萄糖苷酶的抑制能力显著强于阿卡波糖(IC_(50)值为929.59 mg/L)。此外,BGTE-FD和BGTE-SVD对晚期糖基化终产物抑制率分别高达65.28%和63.66%,略低于氨基胍(71.81%)。因此,真空冷冻干燥绿碎茶多酚提取物具有较强的体外抗氧化和抗糖尿病活性及一定的乙酰胆碱酯酶抑制能力,绿碎茶可作为降血糖和抗痴呆产品的潜在资源。

胶原蛋白-茶多酚-肉桂精油涂膜对调理黑鱼鱼片品质的影响

以黑鱼为原料制备调理黑鱼鱼片,研究蒸馏水(CK组)、5%胶原蛋白(C1组)、5%胶原蛋白+0.4%茶多酚(C2组)、5%胶原蛋白+1.5%肉桂精油(C3组)和5%胶原蛋白+0.4%茶多酚+1.5%肉桂精油(C4组)涂膜处理对其在冷藏过程中品质的影响。结果表明:在4℃密封冷藏条件下,涂膜处理可以有效延缓调理黑鱼鱼片冷藏过程中菌落总数、挥发性盐基氮含量和硫代巴比妥酸值的增加,维持调理黑鱼鱼片的L^(*)值、硬度和弹性等,抑制肌原纤维蛋白含量、总巯基含量和Ca^(2+)-ATPase活性的降低。CK组鱼片的菌落总数在冷藏9 d时达到了1.70×10^(6) CFU/g,而C4组鱼片的菌落总数在冷藏15 d时为1.91×10^(6) CFU/g,说明5%胶原蛋白+0.4%茶多酚+1.5%肉桂精油涂膜处理可以延长调理黑鱼鱼片保质期6~7 d。这为调理黑鱼鱼片以及其他水产品的保藏提供了参考。

茶多酚-薏苡仁醇溶蛋白可食用涂膜特性及其对香蕉贮藏品质的影响

【目的】探明添加外源性抗氧化物质对薏苡仁醇溶蛋白可食用膜结构及功能性质的影响,并测定可食用涂膜对香蕉贮藏期间的品质及生理变化的影响,为薏苡仁深度开发利用提供理论依据和技术支撑。【方法】取薏苡仁醇溶蛋白,添加增塑剂(甘油)及不同浓度茶多酚(2%、4%、6%、8%),通过流延法制备茶多酚-薏苡仁醇溶蛋白可食用涂膜,并鉴定涂膜特性。香蕉样品涂膜处理后,放置在一定温度和湿度环境下贮藏,每隔3 d检测样品的重量损失、色泽变化、总叶绿素含量及褐变指数。【结果】薏苡仁醇溶蛋白膜液中添加茶多酚后,涂膜厚度没有改变,水分含量增加,透明度、溶解度、拉伸强度和断裂伸长率均降低。茶多酚-薏苡仁醇溶蛋白可食用涂膜能降低香蕉重量损失、抑制总叶绿素分解和香蕉褐变。【结论】茶多酚-薏苡仁醇溶蛋白可食用涂膜对香蕉贮藏保鲜具有一定作用,可有效延长贮藏期。

茶多酚、鱼骨粉复合制剂对福瑞鲤生长性能、消化及抗氧化能力的影响

研究以福瑞鲤(Cyprinus carpio FFRC)幼鱼为研究对象,研究茶多酚、鱼骨粉制成的复合制剂(商品名“血停”)对福瑞鲤生长、体成分、抗氧化性能以及消化器官组织结构的影响。研究选取180尾健康、大小[(1.92±0.01)g]均匀的福瑞鲤,随机分为对照组和试验组,每组3个重复,对照组投喂商品饲料,试验组在商品饲料的基础上添加0.8%的复合制剂,在循环水系统下养殖8周。结果表明,添加复合制剂对福瑞鲤的生长、形体指标、体成分以及血清生化指标均无影响(P>0.05),但能显著提高福瑞鲤肠道脂肪酶活性以及肝脏和血清的过氧化氢酶(CAT)活性(P<0.05),对肝脏和血清的超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量无影响(P>0.05);试验组福瑞鲤的肠道肌层厚度、绒毛高度显著低于对照组,绒毛宽度显著高于对照组(P<0.05);对福瑞鲤肝脏形态结构均无显著差异(P>0.05)。上述结果表明,该复合制剂对福瑞鲤的生长性能没有负面影响,可提高福瑞鲤的消化、抗氧化能力,可作为一种潜在的饲料添加剂。

显齿蛇葡萄叶提取物体外抗氧化效果研究

为研究显齿蛇葡萄叶提取物的体外抗氧化效果,以维C和茶多酚为对照,分别测定了3种抗氧化物对ABTS自由基、超氧阴离子、DPPH自由基、羟基等的清除率。结果表明,3种抗氧化物的清除率均随其质量浓度的增加而增大,抗氧化效果随其质量浓度的增加而增强。当质量浓度为150μg/mL时,3种抗氧化物对ABTS自由基清除率均为99%,三者抗氧化效果相同;显齿蛇葡萄叶提取物抗超氧阴离子氧化效果远超维C和茶多酚,最高清除率为86.31%;不同质量浓度的显齿蛇葡萄叶提取物对DPPH自由基的清除率均高于90%;低质量浓度时,显齿蛇葡萄叶提取物的抗羟基自由基氧化效果最好,当质量浓度超过250μg/mL时,其与茶多酚具有相同的抗氧化效果。研究结果可为显齿蛇葡萄叶提取物在食品抗氧化剂研究与开发方面提供参考。

茶多酚抗氧化增效及其在油脂保鲜中的应用研究进展

茶多酚(Tea Ployphenols,TP)是茶叶中重要的功效成分,在医药卫生、保健食品行业中有较广泛的应用,但因其脂溶性较差而限制了在脂类食品保鲜中的应用。目前可通过溶剂法、包埋法、酰化修饰、酶催化修饰等方法增加茶多酚脂溶性。使用复配型茶多酚抗氧化剂的抗氧化效果往往要比使用同剂量的茶多酚本身效果强,即不同抗氧化剂之间可能存在协同增效作用。茶多酚发挥其抗氧化效用主要通过与自由基结合,且可通过螯合金属离子、偶联反应等与其他抗氧化剂作用以起到协同增效的效果。通过以上复配过程,茶多酚可有效防止植物油和动物油脂酸败。文章全面综述了增强茶多酚脂溶性的常见方法并对其优缺点作出相应分析总结,分析了目前茶多酚与其他天然抗氧化剂协同增效机理,并重点阐述了其在油脂防酸败中的应用,为后续研究提供指引和参考。

茶多酚的提取分离技术与其体外抗氧化活性研究

茶多酚是一种提取自茶叶的具备较强的抗氧化作用的活性成分,被广泛应用于医疗与食品等领域中。目前,已受到国内外众多学者的关注并参与研究。有关茶多酚的提取分离技术与其抗氧化活性及药用价值得到了深入的研究。现对茶多酚的药用价值、提取分离技术与抗氧化活性进行综述。

三种多酚类物质协同L-精氨酸对冷藏鸡肉糜氧化稳定性和品质的影响

为探讨苹果多酚(Apple polyphenols,Ap)、葡萄籽提取物(Grape seed extraction,GSE)和茶多酚(Tea polyphenols,Tp)分别协同L-精氨酸(L-arginine,L-Arg)对冷藏鸡肉糜氧化稳定性和品质特性的影响,在肉糜中添加5 g/kg L-Arg,再分别加入0.2 g/kg的Ap、GSE、Tp,以添加0.2 g/kg丁基羟基茴香醚(Butylated hydroxy anisole,BHA)作为阳性对照,分别在冷藏1、3、5、7 d时测定各组鸡肉糜硫代巴比妥酸(Thiobarbituric acid reactive substances,TBARS)值、总巯基含量、羰基含量、表面疏水性、pH、蒸煮损失率和色度值。结果表明,与空白(不添加多酚类物质、L-精氨酸及BHA)和BHA相比,L-Arg+Tp可以更好地抑制鸡肉糜的TBARS、羰基含量、pH和表面疏水性的升高,减缓总巯基含量和红度值的降低。L-Arg+Ap和L-Arg+GSE与BHA的抗氧化作用相近。综上所述,在冷藏过程中L-Arg协同3种多酚类物质均可以抑制鸡肉糜的脂肪和蛋白质氧化,改善其品质特性,其中L-Arg+Tp的效果最好。

葡萄籽提取物、茶多酚可食性活性包装膜对罗非鱼的保鲜作用

为提高罗非鱼贮藏品质,延长其货架期,以海藻酸钠(sodium alginate,SA)、纳米纤维(nanofiber,NCC)为基材,添加葡萄籽提取物(grape seed extract,GSE)、茶多酚(tea polyphenols,TP)制备可食性活性包装膜,用于鱼肉的保鲜,分析不同复合保鲜膜处理对罗非鱼的保鲜效果。通过测定鱼肉持水力、色泽、pH、硫代巴比妥酸(thiobarbituric acid,TBA)值、挥发性盐基氮(total volatile basic nitrogen,TVB-N)值以及鱼肉肌纤维蛋白溶解度、巯基含量、羰基含量、表面疏水性等指标,研究贮藏过程中鱼肉品质的变化及蛋白氧化变性程度。结果表明,与对照组(CK)、SA-NCC组相比,含GSE、TP的GT-SA-NCC膜包封的鱼肉持水力较高,pH、TBA、TVB-N值上升速率较慢;鱼肉肌原纤维蛋白溶解度、巯基含量最低,羰基含量、表面疏水性较高,GSE、TP的加入有利于复合膜延缓罗非鱼脂质及蛋白氧化,维持鱼肉贮藏过程中的品质特性及蛋白的功能性质。

茶多酚对氧化应激小鼠的抗氧化研究

氧化应激会造成脂质过氧化,诱导细胞凋亡且损伤细胞遗传物质,进而影响动物正常的生长发育过程。本文对喂饲茶多酚的小鼠进行氧化应激诱导,通过监测诱导后小鼠的体重和进食量,检测其血清和肝脏抗氧化指标,研究茶多酚对小鼠氧化应激的缓解效用。结果显示,氧化应激诱导前,各组小鼠的体重及进食量差异无统计学意义;氧化应激诱导后,应激组血清中的超氧化物歧化酶含量及总抗氧化水平显著下降,而茶多酚可以有效提高血清的抗氧化水平。同时,应激组小鼠肝脏过氧化氢酶及超氧化物歧化酶含量降低,丙二醛含量升高,而茶多酚处理可提高小鼠肝脏过氧化氢酶及超氧化物歧化酶含量,这表明茶多酚可以有效提高血清抗氧化水平,并保护小鼠肝脏,降低敌草快引起的氧化应激损伤。目的在于为进一步研究茶多酚缓解畜牧养殖中氧化应激提供参考。

Comparative Analysis of the Antioxidant and Free-Radical Scavenging Activities of Different Water-Soluble Extracts of Green, Black and Oolong Tea Samples

Extracts of 40 green, black or oolong high quality tea samples from China, Japan or India among others, have been prepared according to the manufacturer instructions and assayed for total polyphenols content using the Folin-Ciocalteu phenol reagent. In addition, the antioxidant activity was assessed by the CUPRAC method and the free-radical scavenging activity was determined using the antioxidant-promoting decay of the stable free-radical DPPH. Caffeine and the most important catechins were identified using RP-HPLC previously validated method. Results from this study suggest that teas, even though they content similar amounts of caffeine, differ considerably in polyphenolic content and therefore in antioxidant and free-radical scavenging activities, depending on the part of the plant used and the process applied to the material for the preparation of the final tea presentation. Correlations among Folin-Ciocalteau’s reactivity of tea samples, the neocuproine reactivity, the DPPH decolourization and the HPLC analysis suggest that the antioxidant activity is due essentially to polyphenolic compounds present in teas, mainly EGCG. The best extraction method of tea powder was the one indicated by dealers. In general, the richest samples belong to green teas and the poorest samples belong to the black teas.