迎春叶黄酮的提取纯化及清除自由基活性研究

Studies on Extraction and Purification of Flavonoids from Leaves of Jasminum nudiflorum Lindl.and Their Antifreeradical Activity

研究迎春叶总黄酮(FLJN)的提取、分离、纯化条件及其体外清除自由基的能力。正交试验结果显示最佳提取方法为:采用75%的乙醇水溶液为提取液,1∶15(g∶mL)的固液比,水浴回流热提取3次,每次40 min。粗提物经过活性炭吸附法进一步处理后,可得总黄酮质量分数为97.6%的精制产品。体外实验表明,FLJN可以有效地清除二苯基苦基苯肼自由基(DPPH.)和羟自由基(.OH),自由基清除率为50%时溶液的质量浓度(IC50值)分别为8.40和2.24 mg/L,其清除自由基的能力与芦丁基本相当,比2,6-二叔丁基-4-甲基苯酚(BHT)稍弱。

The extraction and purification conditions of flavonoids from leaves of Jasminum nudiflorum Lindl. （FLJN） and their abilities of eliminating free radicals were researched. The results of orthogonal experiment showed the optimum extraction conditions were： material with 15-fold ethanol of 75 % as solvent was refluxed in water-bath for three times, each for 40 min. The crude extract was treated with active carbon to obtain purified product with flavonoids content of 97.6 %. Experiments in vitro showed FLJN could scavenge free radicals such as DPPH· and · OH. The IC50 （ the amount of sample needed to eliminate 50 % of free radical） were 8.40 and 2.24 mg/L, respectively. Its antifreeradical ability was nearly the same as that of rutin and slightly weaker than that of dibutyl hydroxy toluene （BHT）.