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以山茶花为试材,采用有机溶剂法和大孔树脂吸附法提取茶多酚,研究比较了2种提取方法的多酚得率及纯度,测定其清除1,1-二-苯基-2-三硝基苯肼(DPPH)、对羟自由基(·OH)、抗超氧阴离子(O2-.)和总抗氧化能力,为山茶多酚抗氧化活性物的鉴定和综合利用提供参考.结果表明:大孔树脂吸附法提取多酚(89.34%)纯度比有机溶剂提取多酚(72.28%)纯度好.以大孔树脂吸附法提取的茶多酚做抗氧化活性试验表明,茶多酚对DPPH的最大清除率达到92.86%,对·OH的最大清除率为90.77%,对O2-.的最大清除率仅为47.79%,0.5 mg/mL茶多酚的总抗氧化能力为17.35 U/mg. 相似文献
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《果树学报》2017,(3)
【目的】探讨草莓果实衰老过程中超微弱发光(ultraweak luminescence,UWL)与活性氧的关系。【方法】以‘红颜’草莓果实为试材,采用H_2O_2处理和茶多酚处理草莓果实,对比分析促进和清除活性氧条件下草莓果实衰老过程中UWL和活性氧的变化及2者之间的关系。【结果】在草莓果实衰老过程中,H_2O_2处理、茶多酚处理和对照的脂氧合酶(LOX)活性和过氧化氢(H_2O_2)含量均先上升后下降,整体上升;超氧阴离子(O_2~)产生速率、丙二醛(MDA)含量和相对电导率均持续上升;H_2O_2处理和对照的UWL均下降、茶多酚处理的UWL上升。在整个果实衰老过程中,H_2O_2处理的O_2~产生速率、MDA含量和相对电导率均高于对照,茶多酚处理后3者均低于对照;H_2O_2处理的UWL强度均低于对照,茶多酚处理的UWL强度均高于对照。【结论】在草莓果实衰老过程中,UWL强度随着活性氧水平的积累而下降;促进活性氧情况下加剧了草莓果实活性氧上升积累,同时加剧了UWL强度下降;清除活性氧则缓减了活性氧上升积累,同时缓减了UWL强度下降。以上结果暗示活性氧并不是引发UWL的直接来源,而应是通过影响其他细胞结构或物质代谢从而间接影响UWL。 相似文献
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采用不同浓度的茶多酚处理“金太阳”杏果实,分析茶多酚处理对“金太阳”杏贮藏过程中超氧阴离子产生(O2(-))及MDA含量的影响,及不同浓度处理间的差异性.结果表明:0.1%(W/V)和0.2%的茶多酚处理使杏果实在贮藏期O2(-)产生速率和MDA含量明显降低,且与对照差异显著;而0.4%和0.6%的茶多酚处理对杏果实贮藏过程中O2(-)产生速率和MDA含量没有明显降低效果,且与对照基本无显著差异.说明较低浓度的茶多酚处理能够有效减少杏果实贮藏期的产生,减轻膜脂过氧化作用,从而延缓果品的衰老. 相似文献
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用茶多酚和大豆分离蛋白混合液处理刺芹侧耳(Pleurotus eryngii),结合聚乙烯(PE)保鲜袋包装低温(10±1℃)贮藏,评定贮藏过程中刺芹侧耳感官指标的变化,并测定其呼吸强度、可溶性固形物含量、褐变度及失重率等各项指标的变化,分析大豆分离蛋白与茶多酚对刺芹侧耳进行涂膜保鲜的可行性。结果表明:大豆分离蛋白中添加茶多酚可明显抑制其褐变度和呼吸强度的上升、降低其失重率,减少其贮藏期可溶性固形物的损失,对刺芹侧耳的保鲜效果优于单一涂膜剂和蒸馏水对照,涂膜保鲜剂中添加茶多酚量为2%时保鲜效果最佳。 相似文献
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茶叶中含有茶多酚,茶多酚是纯天然的,拥有很强的抗氧化作用,是目前人工不能合成的纯天然、多功能、高效能的抗氧化剂和自由基净化剂。一般我们经过对粗茶的萃取、冷凝、浸提、回流和蒸发,然后可以通过分光光度法和标准的曲线法来计算出粗茶中茶多酚的含量。 相似文献
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Zhao-Tang Ding Qing-Ping Ma 《The Journal of Horticultural Science and Biotechnology》2016,91(5):506-513
In this study, two tea varieties (Camellia sinensis cv. CsCr02 and CsCr03) were studied under natural cold conditions to investigate the differences of thylakoid membrane structure, fatty acid desaturase (FAD) genes, and fatty acid (FA) composition in response to low temperatures. Quantitative real-time polymerase chain reaction assay confirmed that the expression of CsFAD8 in leaves of the two tea varieties was much higher than that of CsFAD7. The expression of both genes in CsCr03 was higher than in CsCr02. Electron microscopy showed that the damage to the thylakoid membrane in CsCr03 was less severe than in CsCr02 during the decrease of natural temperature. Changes in thylakoid membrane integrity coincided with the gradual decline in chlorophyll concentration and chlorosis of the tea leaves. With the decrease of natural temperature, a decline in the trienoic FA species (16:3 and 18:3) and an increase in the dienoic species (18:2) were observed in the two varieties. These results indicate that CsCr03 has higher cold adaptability compared to CsCr02. 相似文献
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茶树品种资源遗传多样性的AFLP研究 总被引:22,自引:1,他引:22
利用AFLP - 银染分子标记技术, 对40个茶树品种(系) 进行遗传多样性与亲缘关系分析。选用多态性高、分辨力强的引物组合E-ACG/M-AAC、E-AGG/M-AAG与E-AGG/M-AGT分别对供试材料的基因组DNA进行扩增, 共获得226条清晰可辨的带, 其中多态性带207条, 多态位点百分率为91.59% ,这表明供试品种资源在DNA水平上酶切位点的分布存在广泛的变异。40份资源所检出的位点平均有效等位基因数、平均基因多样度、平均Shannon信息指数, 分别为1.59 ±0.09、0.35 ±0.04、0.53 ±0.05。应用SPSS软件计算遗传距离介于0.13~0148之间, 平均为0.32; UPGMA法将40份资源分成4个类群, 从相似性系数分析了各品种资源间的亲缘关系。 相似文献
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茶皂素对乐果防治菜缢管蚜的增效作用 总被引:4,自引:1,他引:3
试验分别测定了不同浓度的茶皂素、乐果及茶皂素与乐果混剂对菜缢管蚜的毒力。结果表明,茶皂素本身对菜缢管蚜的毒力很低,但其对乐果有极显著的增效作用。同浓度的乐果药液凡是加入了茶皂素的处理蚜虫死亡率均明显比未加的单剂高。24小时测定乐果单剂、乐果+500mg/L茶皂素(TS)和乐果+1000mg/LTS处理的LC50分别为40.15、32.87和18.59mg/L;而48小时测定的LC50则分别为15.33、10.11和7.77mg/L。 相似文献
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AIM: To investigate the effect of tea-polyphenols (TP) on the lipoprotein lipase (LPL) and hepatic lipase (HL) activity in atherosclerosis (AS) rabbits. METHODS: The rabbits feeding lipodiet were taken in 200 μg·g-1·d-1 TP through the experiment. The LPL and HL activity in the plasma of rabbits were detected. The LPL activity in the arteria tissue and HL activity in liver tissue were estimated with histochemistry technique. RESULTS: The LPL and HL activity in the plasma were not significantly different between premier and post experiment in AS rabbits (P>0.05), between AS group and control group (P>0.05). The LPL activity in the arteria tissue were not different between AS group and control group (P>0.05). HL activity in liver tissue in AS group was significantly lower than control group (P<0.05), but TP group was higher than AS group (P<0.05). In TP group, the TC and LDL-c level in plasma were lower (P<0.05), and the area of atherosclerosis plaque were smaller than those in AS group (P<0.05). CONCLUSION: TP increased HL activity in liver tissue in AS rabbits, which correlated with decreasing the TC and LDL-c level in plasma and the area of atherosclerosis plaque. 相似文献
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茶皂素对菜青虫幼虫的拒食活性 总被引:1,自引:0,他引:1
测定了茶皂素对菜青虫幼虫的拒食作用。结果表明,当浓度高于800mg·L-1时,茶皂素对菜青虫3、4、5龄幼虫均有很强的拒食活性;24h(小时)的拒食中质量浓度AFC50分别为130.36、172.97和220.86mg·L-1。田间小区试验结果显示,60%的茶皂素原粉150倍(4000mg·L-1)和300倍(2000mg·L-1)液对芥蓝菜具有很好的保叶效果,对菜青虫的为害有一定的控制作用。 相似文献
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根据日照市茶树生长自然环境条件,对影响茶树冻害的因子以及越冬防护模式进行试验研究,总结出茶园施用有机肥+浇越冬水+地面覆盖+薄膜覆盖越冬新模式,可供北方同类茶区参考。 相似文献