枇杷叶总黄酮的提取及其脂质体的抗氧化活性

Studies on Flavonoids Extraction from Loquat and Their Liposomes Antioxidant Activity

采用乙醇回流法提取枇杷叶中黄酮类物质,制备黄酮脂质体,并考察其抗氧化活性及各因素对总黄酮提取率的影响.优化总黄酮脂质体制备处方,并测定其抗氧化活性.优化结果表明:最佳提取工艺中乙醇体积分数为70%,料液比为1:60,提取温度为80℃,提取时间为1.5h;黄酮脂质体最佳处方中卵磷脂与胆固醇的质量比为4∶1,卵磷脂与黄酮的质量比为20∶1,磷酸盐缓冲液pH值为5.8.体外抗氧化结果显示:不同质量比的黄酮及其脂质体对猪油都具有一定的抗氧化作用,且随着其剂量的增加而增强;质量分数相同时,黄酮脂质体的抗氧化效果优于黄酮溶液,且与抗坏血酸有较好的协同抗氧化增效作用.

Alcohol reflux was used to extract flavonoid components from loquat leaves and then the flavonoids liposomes were prepared.The antioxidant activity of the liposomes and the influence of various factors on extraction rate were investigated.During these processes,we also optimized the preparation prescription of flavonoids liposomes and then determined their antioxidant activity.The optimum extraction process as follows： 70% ethanol concentration,liquid feed ratio 1∶60,extraction temperature 80 ℃,extraction time 1.5 h.The best prescription for the flavonoids liposomes： lecithin and cholesterol ratio of 4∶1,lecithin and flavonoids ratio of 20∶1,phosphate buffer at pH 5.8.Antioxidant results in vitro showed that flavonoids with different mass ratio and their liposomes had some antioxidant effect on lard oil,and the effect increased when the dose increased.If the mass ratio was the same,the antioxidant effect of the flavonoids liposome was better than that of the flavonoids solution,and it had good antioxidant synergy effect when used with ascorbic acid.