双水相萃取法提取地骨皮多酚及抗氧化活性研究

Extraction of polyphenols from Lycii Cortex based on aqueous two-phase system and evaluation of its antioxidant capacity

采用超声辅助双水相萃取法提取地骨皮中多酚类物质,通过单因素实验和正交实验对地骨皮多酚提取工艺进行优化,最佳提取工艺条件为:乙醇溶液质量分数为41%,硫酸铵与乙醇溶液质量比为13∶100(g/g),地骨皮与乙醇溶液质量比1∶20(g/g),超声时间为50 min,提取温度为55℃,在此条件下地骨皮多酚得率为17.88 mg/g。分别以DPPH法、ABTS法、ORAC法、细胞内总谷胱甘肽含量和SOD活性评价地骨皮多酚的抗氧化能力。结果表明,地骨皮多酚对DPPH·和ABTS·的IC50分别为20.00 mg/L和59.37 mg/L,对活性氧清除能力高于同浓度Trolox,对H_(2)O_(2)损伤的HSF细胞内谷胱甘肽含量和SOD活性均有显著的提升作用。

The polyphenols were extracted from Lycii Cortex by ultrasonic assisted aqueous two-phase system.The optimized conditions were as follows:the mass fraction of 41%ethanol solution;ammonium sulfate to ethanol solution,13∶100(g/g);ratio of Lycii Cortex to liquid was 1∶20(g/g);ultrasonication at 55℃for 50 min.The yield of Lycii Cortex polyphenols(LCPPs)was 17.88 mg/g under the optimum condition.The antioxidant capacity of LCPPs were evaluated by assays of DPPH,ABTS,FRAP,ORAC,intracellular GSH content and SOD activity.The results showed that the IC 50 of DPPH·and ABTS·by LCPPs were 20.00 mg/L and 59.37 mg/L respectively;the scavenging capability of reactive oxygen species by LCPPs was higher than Trolox at the same concentration;LCPPs can significantly increase the T-GSH content and SOD activity.