茶多酚与绿原酸生物活性的比较研究

为了研究茶叶与金银花中主要药效成分茶多酚和绿原酸生物活性的差异,应用过氧化值测定法、分光光度法、最小抑菌浓度(MIC)测定法分别比较茶多酚和绿原酸的抗氧化性、自由基清除能力、体外抑菌活性;结果表明在6周的观测期内,浓度为100μg/g和200μg/g的茶多酚可将猪油的POV抑制在10meq/kg范围内,且抗氧化能力随浓度增加而增强,这与81%绿原酸有相似结果;20%绿原酸、81%绿原酸、95%茶多酚对DPPH和·OH的半数抑制浓度(IC50)分别为327、1432、65、135、52mg/L和1908mg/L;95%茶多酚对大肠杆菌和金黄色葡萄球菌的MIC分别为500μg/g和250μg/g,81%绿原酸和20%绿原酸相应值分别为500μg/g、500μg/g和500μg/g、1000μg/g;研究结论为茶多酚(95%)在抗氧化性、清除DPPH能力及对金黄色葡萄球菌的抑菌效果方面都要强于绿原酸(81%),在清除·OH能力上要弱于绿原酸,在食品、药品行业中茶多酚有望比绿原酸发挥更大的作用。

A Comparative Study on Bioactivities of Tea Polyphenols and Chlorogenic Acid

Objective to study the differences of bioactivities of tea polyphenols (TPs) and chlorogenic acid (CHA), methods of POV assay、spectrophotometric determination and MIC were used to compare the antioxidation、 scaventing free radicals and antibacterial action of TPs & CHA. Results in the six weeks showed that TPs (100 μg/g、 200 μg/g) could restrain the POV of lard below 10 meq/kg, antioxidation rises with concentrations of TPs, as resemble the effect of CHA (81%). On the free radicals, CHA showed selective scaventing ability, IC50(DPPH、·OH) of CHA (81%) is 65 mg/L and 135 mg/L, and CHA (20%) is 327 mg/L and 1 432 mg/L, but TPs is 52 mg/L and 1908 mg/L; In the antibacterial action, TPs and CHA can obviously inhibit both staphylococcus aureus and escherichia coli., The MIC of CHA (81%) is twice as that of CHA (20%) on staphylococcus aureus, 500 μg/g and 1 000 μg/g respectively, that of TPs is 250 μg/g, on escherichia coli.. Conclusion: TPs (95%) exceeds CHA (81%) and CHA (20%) in the antioxidation、scaventing DPPH and antibacterial activity on staphylococcus aureus, but the reverse was in the scaventing ·OH. It was regarded that TPs may play a more important role than CHA in the food and drug.