桂花不同溶剂提取物对氧自由基清除作用的ESR研究

目的研究桂花不同提取物对氧自由基的清除作用。方法利用不同极性溶剂（水、石油醚、乙酸乙酯、正丁醇）浸提桂花粉后得到不同极性的提取物。通过电子自旋共振（ESR）和自旋捕集技术,以1,1-二苯基-2-三硝基苯肼自由基（DPPH）及核黄素光照条件下产生超氧阴离子O2^-自由基体系,检测桂花中各组分清除DPPH自由基及O2^-的能力。结果以维生素C为对照,桂花水提取物、石油醚提取物、乙酸乙酯提取物、正丁醇提取物及维生素C清除DPPH自由基能力IC50分别为59.63,53.93,28.33,38.89,40.93μg·mL^-1;各提取物及维生素C对超氧阴离子O2-自由基清除能力IC50分别为63.37,55.47,30.20,48.36,41.52μg·mL^-1。其中各提取物的乙酸乙酯提取物的DPPH及O2^-清除率最大。结论通过比较各组分对DPPH自由基及超氧阴离子自由基的清除能力,了解桂花中抗氧化成分在各相中的分布情况,并据此进行有目的的分离桂花中的抗氧化成分。

ESR Studies on the Scavenging Effect on Oxygen Free Radicals in Different Extracts from Osmanthus Fragrans

OBJECTIVE To research scavenging effect on the oxygen free radicals in different extracts from Omanthus fragrans.METHODS Different polar extracts in Omanthus fragrans were obtained by different solvents such as water,petroleum ether,ethyl acetate and n-butanol.1,1-diphenyl-2-picrylhydrazyl(DPPH) free radical and superoxide anion free radical(O 2-) produced in lactoflavin illumination system were measured by electron spin resonance(ESR) and spin trapping technology.The scavenging effects of different extract...