云南栘［木衣］叶提取物片段抗氧化活性及成分分析

目的:评价云南栘[木衣]叶萃取物的抗氧化活性,为云南栘[木衣]抗氧化功能食品、营养补充剂等的开发提供理论依据.方法:用系统溶剂萃取法将云南栘[木衣]叶的萃取物再分成石油醚萃取物、乙酸乙酯萃取物、正丁醇萃取物和水相4部分.用DPPH·法和总还原力法评价云南栘[木衣]叶4个不同萃取物的抗氧化活性.用DPPH·-HPLC-PDA和总还原力-HPLC-PDA柱前衍生法对云南栘[木衣]叶中的抗氧化成分进行了筛选.结果:云南栘[木衣]叶提取物不同极性分离物都具有良好的抗氧化活性,其中乙酸乙酯萃取物的萃取得率高达67.87%,DPPH·半清除体积质量分数为0.079mg/mL,总还原力的芦丁质量分数为(0.199 70±0.000 31)g/g,是云南栘[木衣]叶抗氧化活性的主要来源.云南栘[木衣]叶提取物中主要有9个抗氧化成分,主要集中于乙酸乙酯萃取物,其中4个为黄酮类化合物.结论:云南栘[木衣]叶是良好的天然抗氧化剂来源,具有抗氧化营养补充剂、功能食品的开发潜力,抗氧化成分筛选结果为云南栘[木衣]抗氧化功能的开发提供了方向.

On Evaluation of Antioxidant Activities and Screening of Potential Antioxidant Compounds from Docynia delavayi (Franch .) Schneid .Leaves

The antioxidant activity of Docynia delavayiSchneid .leaf has been estimated in this paper .It provides theoretical basis for developing Docynia delavayiantioxidant nutritional supplement . Docynia delavayiSchneid .leaf extract has been separated by different polarity solvents :petroleum ether ,ethylace-tate ,n-butanol and water via systematic solvent extraction .Antioxidant activities of different polarity frac-tions have been evaluated by DPPH · assay and total reducing power assay .Its potential antioxidant com-pounds have also been screened by DPPH ·-HPLC-PDA assay and total reducing power-HPLC-PDA as-say .All polarity fractions of Docynia delavayiSchneid .leaf extract have exhibited high antioxidant activi-ty .The yield of ethylacetate fraction reached up to 67 .87% .The DPPH · SC50 value and total reducing power of ethylacetate fraction are 0 .079 mg/mL and (0 .19970 ± 0 .00031) g/g ,respectively .The antioxi-dant activity of Docynia delavayiSchneid .leaf mainly comes from ethylacetate fraction .9 antioxidants mainly concentrating in ethylacetate fraction are screened and 4 of them are flavones .It is concluded that Docynia delavayiSchneid .leaf is a good source of natural antioxidants and the result of antioxidants screening could be used to guide Docynia delavayiantioxidant nutritional supplement development .