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1.
Green tea contains catechins and caffeine as major constituents. Treatment of rats with green tea (2.5% w/v) significantly increased 7-ethoxycoumarin O-deethylase (7-ECOD), caffeine N-1 demethylase (CN1D) and UDP-glucuronyltransferase (UGT) activities. Treatment with caffeine similarly activated CYP1A2 and related monooxygenases as well as UGT, while treatment with catechins induced UGT activity but not 7-ECOD or CN1D activity. Numbers of benzo[a]pyrene (BP)-induced revertant colonies in an Ames test (mutation assay) with S. typhimurium TA98 as the test strain were markedly larger when BP was preincubated with the liver S-9 (9000 x g supernatant of liver homogenate) from green tea-treated rats than when preincubated with that from control rats. In a modified Ames assay system in which UGT was activated by the addition of UDP-glucuronic acid to the preincubation mixture, the numbers of revertant colonies in the assay using liver S-9 from green tea-treated rats decreased to a similar level to that in the assay using S-9 from controls. The acceleration of two enzymatic reactions may contribute to the rapid elimination of BP; the first step, the formation of a metabolic intermediate (which is mutagenic) by CYP1A2 and the second, the conjugation of active metabolic intermediates by UGT. We speculated that green tea can reduce the amount of time carcinogens reside in the body and the chance that body tissues will be exposed to active metabolites of carcinogens thorough rapid elimination due to the simultaneous induction of CYP1A2 and UGT activities.  相似文献   

2.
Green tea (Camellia sinensis) is a popular herbal plant with abundant health benefits, and thus, it has been used as a potent antioxidant for a long time. Based on the available literature, the diversity and the availability of multifunctional compounds in green tea offer its noteworthy potential against many diseases such as liver and heart diseases, inflammatory conditions and different metabolic syndromes. Owing to its bioactive constituents including caffeine, amino acids, l -theanine, polyphenols/flavonoids and carbohydrates among other potent molecules, green tea has many pharmacological and physiological effects. The effects of green tea include anti-oxidative, anti-inflammatory, anti-arthritic, anti-stress, hypolipidaemic, hypocholesterolaemic, skin/collagen protective, hepatoprotective, anti-diabetic, anti-microbial, anti-infective, anti-parasitic, anti-cancerous, inhibition of tumorigenesis and angiogenesis, anti-mutagenic, and memory and bone health-improving activities. Apart from its utilization in humans, green tea has also played a significant role in livestock production such as in dairy, piggery, goatry and poultry industries. Supplementation of animal feeds with green tea and its products is in line with the modern concepts of organic livestock production. Hence, incorporating green tea or green tea by-products into the diet of poultry and other livestock can enhance the value of the products obtained from these animals. Herein, an effort is made to extend the knowledge on the importance and useful applications of green tea and its important constituents in animal production including poultry. This review will be a guideline for researchers and entrepreneurs who want to explore the utilization of feeds supplemented with green tea and green tea by-products for the enhancement of livestock production.  相似文献   

3.
本文讨论了茶提取物和儿茶素与核酸的相互作用,已有的研究结果表明儿茶素能够清除自由基,诱导癌细胞凋亡,阻止DNA的交联及DNA加成物的形成,还能抑制肿瘤细胞DNA的合成,诱导癌基因表达下调,降低细胞微核率,更重要的是茶提取物能保护DNA不受辐照损伤,抑制G-C、G-A颠换,修复自由基诱导生成的dGMP加合物。可以认为茶是一种天然的健康饮料。  相似文献   

4.
为促进凉茶渣在畜牧业中的资源化利用,本研究以黑曲霉为菌种固态发酵凉茶渣,首先在单因素试验条件下考察了时间、温度、含水量、浸泡液pH、氮源和碳源对凉茶渣降解率和产物pH的影响;再根据单因素试验结果和规模化生产实际需要,以4%硫酸铵为氮源,2%葡萄糖为碳源,以降解率为考察指标,通过正交试验优化发酵工艺;并通过检测超氧自由基清除率、羟基自由基清除率和1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除率,评价凉茶渣在最优工艺条件下发酵前后抗氧化活性的变化。结果发现,含水量为60%,浸泡液pH为9.0,31℃发酵168 h是凉茶渣的最佳发酵工艺参数。最佳工艺条件下凉茶渣的降解率为25.23%,发酵产物pH为4.53。当凉茶渣发酵前水提液浓度为24 mg/mL时,超氧自由基清除率为43.56%,羟基自由基清除率为47.06%,DPPH自由基清除率为90.71%;当最优条件下发酵产物水提液浓度24 mg/mL时,超氧自由基清除率为30.77%,羟基自由基清除率为95.63%,DPPH自由基清除率为87.36%。本试验结果表明,黑曲霉是适宜的凉茶渣发酵菌种,且凉茶渣经过黑曲霉发酵后具有良好的抗氧化活性。  相似文献   

5.
Supplementation of pigs with vitamin E, the most important lipid-soluble antioxidant, has been shown to improve meat quality and animal health. Previous studies in cultured cells and laboratory animals indicate synergistic effects between polyphenols and vitamin E. The present feeding trial was undertaken to investigate the effects of dietary green tea polyphenols (GTP) on vitamin E status, antioxidative capacity and parameters of meat quality in growing pigs. Eighteen castrated, crossbred, male pigs received a flavonoid-poor diet based on corn starch, caseinate and rapeseed oil with a total vitamin E content of 17 IU/kg diet over a period of 5 weeks. This basal diet was supplemented with green tea extract to provide daily doses of 0 (control), 10 and 100 mg GTP/kg body weight. Dietary supplementation of growing pigs with GTP did not affect serum, liver, lung and muscle vitamin E (α- and γ-tocopherol) concentrations, plasma antioxidant capacity (ferric reducing ability of plasma, trolox equivalent antioxidant capacity) or parameters of meat quality including meat temperature, pH, conductivity, colour and drip loss. In conclusion, supplementation of pig diets with green tea catechins is not associated with improved antioxidant status and meat quality under practice-oriented conditions.  相似文献   

6.
The use of herbs as additives in livestock nutrition as an alternative to antibiotics is becoming a new goal in animal production. It is known that green tea exerts antimicrobial activity owing to specific flavonoid compounds named catechins, primarily represented by epigallocatechin-3-gallate (EGCG). Remarkably, despite many potential benefits of green tea and EGCG consumption, it is also important to get an insight on the possible reproductive-related consequences of feeding supplementation. To this purpose, granulosa cells were harvested from follicles > 5mm and treated with 5 and 50 microg/ml of EGCG in order to evaluate the effects on the main parameters of granulosa cell function: steroidogenesis, by measuring progesterone and estradiol-17beta production, and proliferation, one of the major feature of ovarian follicular growth. Moreover, as the genesis of new vessels has been demonstrated to be fundamental for follicle development, we evaluated the effect of EGCG on the production of the main angiogenetic factor, VEGF, by swine granulosa cells. Finally, since reactive oxygen species (ROS) might be involved in the control of female reproductive activity, we studied the effect of EGCG on superoxide anion (O2-) and hydrogen peroxide (H2O2) production by swine granulosa cells and on the activity of the scavenging enzyme superoxide dismutase (SOD). EGCG significantly (p < 0.05) inhibited proliferation, steroidogenesis, VEGF and O2- production by swine granulosa cells; on the contrary, H2O2 levels and SOD activity were stimulated (p < 0.05) by the catechin. Therefore, since our data demonstrate that EGCG has a negative effect on reproductive performances in swine, feeding supplementation should be carefully considered.  相似文献   

7.
Researches on tea have been developed for decades, which prove that tea, especially green tea, has multiple functional components. With the rapid development of beverage industry, the resultant large amounts of tea grounds attract great attention. However, unreasonable utilization of tea grounds would lead to great waste and environmental pollution, especially in summer. In view of the high nutritive value and multiple functional components, tea grounds could be used as feedstuff. By now, researches of tea grounds as feedstuff are mainly on ruminant, as the utilization on other animals is limited to lower level due to high fiber content. Therefore, the following review will begin with a brief introduction of tea grounds and the possible utilization of tea grounds as feedstuff, and then elaborate on the application of ensiling and total mixed ration on ruminant. Apart from the fermentation quality, nutritive value is also provided to assess feasibilities of using tea grounds as feedstuff resources. Finally, a summary on the utilization situation and future direction of using tea grounds as feedstuff is provided in this review.  相似文献   

8.
Researches on tea have been developed for decades, which prove that tea, especially green tea, has multiple functional components. With the rapid development of beverage industry, the resultant large amounts of tea grounds attract great attention. However, unreasonable utilization of tea grounds would lead to great waste and environmental pollution, especially in summer. In view of the high nutritive value and multiple functional components, tea grounds could be used as feedstuff. By now, researches of tea grounds as feedstuff are mainly on ruminant, as the utilization on other animals is limited to lower level due to high fiber content. Therefore, the following review will begin with a brief introduction of tea grounds and the possible utilization of tea grounds as feedstuff, and then elaborate on the application of ensiling and total mixed ration on ruminant. Apart from the fermentation quality, nutritive value is also provided to assess feasibilities of using tea grounds as feedstuff resources. Finally, a summary on the utilization situation and future direction of using tea grounds as feedstuff is provided in this review.  相似文献   

9.
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 polyphenols are a general term for polyphenol compounds 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.  相似文献   

10.
Caffeine (1,3,7-trimethylxanthine) is a popular mild central nervous system stimulant found in the leaves, seeds and fruits of various plants and in foodstuffs such as coffee, tea, and chocolate, among others. Caffeine is widely used and is not associated with severe side effects when consumed at relatively low doses. Although rarely observed, overdoses can occur. However, only a few fatal caffeine intoxication cases have been reported in the literature. Herein, we report the pathological examination results and information on caffeine concentrations in the blood, urine and main organs in a fatal caffeine intoxication case. Even though high caffeine concentrations were found in the systemic organs, no caffeine-related pathological changes were detected.  相似文献   

11.
为了探讨表没食子儿茶素没食子酸酚(tea polyphenol(-)-epigallocatechin gal-late,EGCG)对羟自由基损伤小鼠海马神经元的保护作用,采用原代细胞培养技术,分离培养18 d小鼠胚胎海马神经元,培养4 d后,加入FeSO4和H2O2进行处理,随后加入不同浓度的EGCG培养24 h,通过观察细胞的形态学变化,四甲基偶氮唑盐(methylthiazolydi-phenyl-tetrazolium bromide,MTT)比色法分析细胞活性,检测神经元中丙二醛(malondi-aldehyde,MDA)以及培养液中乳酸脱氢酶(lactate dehydrogenase,LDH)含量的变化,以探讨EGCG对羟自由基损伤神经元的保护作用。结果显示,EGCG能够抑制神经元MDA的产生,降低神经元细胞外液中LDH的含量,增加细胞的活性,从而进一步证明EGCG能够清除羟自由基产生,减轻羟自由基对神经元损伤,对神经元的存活有一定的保护作用,为其用于治疗中枢神经系统病理性损伤的打下实验基础。  相似文献   

12.
桑叶粗提物清除羟自由基能力的比较   总被引:2,自引:0,他引:2  
实验采用物理化学方法(Phen-CuSO4-Vit.c-H2O2反应体系)测定和比较了桑叶提取物、银杏叶提取物和螺旋藻粗多糖清除羟自由基的能力,并测定了3种提取物中总黄酮、多酚类和糖类成分含量。结果发现,在清除羟自由基能力和延迟羟自由基攻击高峰出现的作用方面,桑叶提取物强于螺旋藻粗多糖,而比银杏叶提取物弱。提取物中总黄酮和多酚类物质的含量与清除羟自由基能力有密切关系。  相似文献   

13.
蜂王浆中小分子物质BHT的抗氧化活性研究   总被引:1,自引:0,他引:1  
为深入探讨蜂王浆的抗衰老功能因子,分别采用邻苯三酚法和Fenton法测定了蜂王浆中存在的2,6-二叔丁基-4-甲基苯酚(BHT)对超氧阴离子和羟自由基的清除率,结果证实BHT对超氧阴离子和羟自由基有很强的清除力,当BHT的浓度达到600mg/L时,对超氧阴离子的清除率达75.86%,为最强;当BHT的浓度达到500mg/L时,对羟自由基的清除率达到84.47%,为最强。  相似文献   

14.
Anticoccidial effects of green tea (GT)-based diets were evaluated in chickens following oral infection with Eimeria maxima an ubiquitous intestinal parasite of poultry that impairs the growth and feed efficiency of infected birds. Five-week-old chickens were assigned to four groups (GT 0.5%, GT 2.0%, untreated/infected and non-infected control) and each group consisted of 15 chickens. Chickens were fed a standard diet supplemented with ground green tea for 2 weeks prior to infection with E. maxima (10,000 sporulated oocysts per bird). The effects of green tea on E. maxima infection were assessed by two parameters, fecal oocyst shedding and body weight gain. The green tea-fed chickens produced significantly reduced fecal oocysts (P<0.05) when compared to the E. maxima-infected group fed standard diet. The green tea-based diet, however, did not improve body weight loss caused by E. maxima infection. This study is the first to demonstrate anticoccidial effect of green tea on Eimeria parasites.  相似文献   

15.
不同加工工艺制成桑叶茶的感观品质及营养活性成分分析   总被引:1,自引:0,他引:1  
通过不同茶叶(绿茶、红茶、乌龙茶)加工工艺试制桑叶茶,用常规的感观评审方法评价其品质,并用生化分析方法测定其营养及生物活性成分,为不同风味的高品质桑叶茶加工工艺的选择提供参考。感观品质评审3种加工工艺制成的桑叶茶具有各自独特的风格:绿茶工艺制成的桑叶茶甘醇香甜,略带桑叶青涩味;乌龙茶工艺制成的桑叶茶爽口醇和,有淡淡的花香;红茶工艺制成的桑叶茶甘甜醇厚,有近似香蕉的果香味。营养及生物活性成分检测结果:3种加工工艺制成桑叶茶的水浸出物、可溶性糖、氨基酸、黄酮类物质含量明显比桑叶固定样中的含量有所上升,而多酚类物质则比桑叶固定样明显减少,其中可溶性糖含量为红茶工艺制成桑叶茶>绿茶工艺制成桑叶茶>乌龙茶工艺制成桑叶茶,且都明显高于桑叶固定样;3种加工工艺制成桑叶茶的蛋白质含量、氨基酸总量以及17种氨基酸组分的含量均高于桑叶固定样,并以绿茶工艺制成的桑叶茶中含量最高;桑叶茶含有的17种氨基酸中,谷氨酸和亮氨酸的含量最高,且乌龙茶工艺制成的桑叶茶的苯丙氨酸、组氨酸和精氨酸等组分含量较高。  相似文献   

16.
本试验旨在探究绿茶粉及绿茶多酚对犬的抗氧化作用。选用5月龄杂交幼犬15只,随机分为3个组,每组5只。对照组饲喂基础饲粮,绿茶粉组饲喂基础饲粮+1.0%的绿茶粉,绿茶多酚组饲喂基础饲粮+0.25%的绿茶多酚。试验期为84 d。结果表明:与试验开始时相比,试验结束时对照组犬体重增长了162%,绿茶粉组犬体重增长了101%,绿茶多酚组犬体重增长了132%,且绿茶粉组和绿茶多酚组试验结束时犬体重显著低于对照组(P0.05),比对照组分别降低了61%和30%。试验第84天,绿茶粉组及绿茶多酚组犬血清中谷丙转氨酶(ALT)、谷草转氨酶(AST)、乳酸脱氢酶(LDH)活性均显著或极显著低于对照组(P0.05或P0.01),血清超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性极显著高于对照组(P0.01),血清丙二醛(MDA)含量极显著低于对照组(P0.01),肝脏抗氧化基因[谷氨酸半胱氨酸连接酶催化亚基(GCLC)、谷氨酸半胱氨酸连接酶修饰亚基(GCLM)、血红素氧合酶1(HO-1)、过氧化氢酶(CAT)]和Ⅱ相解毒酶基因[谷胱甘肽硫转移酶M1(GSTM1)和醌氧化还原酶1(NQO1)]的mRNA相对表达量显著高于对照组(P0.05)。综上所述,在本试验条件下,在犬饲粮中添加1.0%的绿茶粉或0.25%的绿茶多酚均具有保护肝脏、抗氧化、促进Ⅱ相解毒酶基因表达及控制体重的作用。  相似文献   

17.
选取10岁初始体重为34.5~37.5 kg的拉布拉多犬72条,随机分为4组,每组3个重复,每个重复6条,分别饲喂添加0,1 000,2 000和4 000 mg/kg绿茶粉饲料,以研究不同水平绿茶粉对老年犬血清生化指标和抗氧化指标的影响,试验进行60 d。结果表明:随着绿茶粉添加量的增加,谷丙转氨酶、谷草转氨酶、总胆红素逐渐下降,除1 000 mg/kg组外各试验组均显著低于对照组;随着绿茶粉从1 000 mg/kg提高到4000 mg/kg,血清中甘油三酯、胆固醇都显著低于对照组(P<0.05)。尿酸、尿素氮、葡萄糖、高密度脂蛋白和低密度脂蛋白差异不显著(P>0.05)。同时,绿茶粉能显著提高老年犬血清中超氧化物歧化酶(SOD)活力(P<0.05)、谷胱甘肽过氧化物酶(GSH-Px)活力(P<0.01),并能明显降低血清中丙二醛(MDA)含量(P<0.05)。结果提示,添加2 000 mg/kg绿茶粉对老年犬有很好的保健作用。  相似文献   

18.
茶多酚是茶叶的次级代谢产物,因具有抗氧化性、抗癌和预防心血管疾病等作用而被广泛应用于食品和医药行业。茶多酚与牛乳蛋白的相互作用会使牛乳蛋白结构发生变化,进而影响乳制品的功能特性和生物利用度。牛乳蛋白具有特殊的结构,因此其与酚类物质的结合一直受到广泛关注。本文综述了茶多酚与牛乳蛋白的相互作用机理、影响因素、产物特性、机理分析方法的研究进展以及这种相互作用对乳制品功能特性和生物利用度的影响,为后续利用茶多酚和牛乳蛋白联合开发新型产品提供参考。  相似文献   

19.
硒是动物体的必需微量元素,茶多酚是茶叶中具有生物活性的主要物质之一,二者具有多种相似的生物学功能,如抗氧化、提高免疫力、抗肿瘤等,可通过调节多条信号通路进而发挥其功能,在促进动物生产性能、增强抗氧化功能等方面具有协同作用.本文就硒与茶多酚的生物学功能、对细胞内的信号调节机制及在动物生产中的应用进行综述,为进一步研究硒与...  相似文献   

20.
采用电子自旋共振和自旋捕集技术,观察药用鼠尾草丹参二萜醌类化合物及其它中草药中有关单体化合物对Fenten 反应产生的羟自由基的清除效能。结果表明,试验浓度的二萜醌类化合物对羟自由基有不同程度的清除作用,其中对醌类的抑制作用强于邻醌类。含多羟基醌类化合物具有较强的清除效能,分子中的羟基对消除自由基有促进作用。在一定浓度范围内,隐丹参酮对羟自由基有较好的清除作用。  相似文献   

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