桂花酶解物中酚类物质及其抗氧化活性研究

Study on the phenolics of hydrolysates from Osmanthus fragranslour and its antioxidant activity

运用LC-MS/MS对桂花酶解物中的酚类物质进行研究,发现桂花酶解物中含有36种酚类物质,包括单咖啡酰基奎宁酸、咖啡酸4-O-葡萄糖苷、5-O-对香豆酰基奎宁酸、4-O-对香豆酰基奎宁酸、木犀草素-7-O-6″-丙二酰基葡萄糖苷、麦角甾苷、异麦角甾苷等物质。抗氧化活性研究发现,桂花酶解物浓度大于0.8 mg/m L时,对ABTS+、DPPH·自由基清除率达90%以上,均显著高于芦丁(p<0.05),略低于Trolox;桂花酶解物的还原力为3.0左右,显著高于芦丁的1.0左右(p<0.05),稍高于Trolox;桂花酶解物的TEAC和ORAC值分别为648.66μmol Trolox/g和813.53μmol Trolox/g,均显著高于芦丁(p<0.05);桂花酶解物的ABTS+、DPPH·自由基清除能力和还原力与总酚含量均呈显著的线性正相关。

The present study investigated the phenolics of hydrolysates of Osmanthus fragranslour by LC-MS/MS. The research results demonstrated that hydrolysates of Osmanthus fragranslour contained 36 varities of phenolics,including Caffeyolquinic acid,Caffeic acid 4-glucoside 4-O-p-coumaroylquinic acid,5-O-p-coumaroylquinic acid,Luteolin-7-O-6″-malonylglucoside,Acteoside,Isoacteoside etc. This study also evaluated the antioxidant activity of hydrolysates of Osmanthus fragranslour,Trolox and Rutin. It showed that scavenging activity of ABTS＋and DPPH· free radical and reducing power of hydrolysates from Osmanthus fragranslour reached 90 % and were slightly lower than Trolox, but significantly higher than Rutin（ p〈0. 05）, when the concentration was greater than 0.8 mg/m L. The values of TEAC and ORAC of hydrolysates from Osmanthus fragranslour were 648.66 μmol Trolox/g and 813.53 μmol Trolox/g and significantly higher than Rutin（p〈0. 05）. It was observed that the scavenging activity of ABTS＋and DPPH· free radical and reducing power of hydrolysates from Osmanthus fragranslour had a significantly positive correlation with the contents of polyphenolics.