不同品种苹果多酚体外抗氧化能力评价

目的:为了研究不同品种苹果间多酚抗氧化能力的差异,试验选择了13种苹果进行总多酚和各单体酚抗氧化能力的测定。方法:采用蒸汽爆破协助超声波溶剂萃取苹果多酚,检测苹果多酚和各单体酚对DPPH自由基、NO₂^-自由基、O₂^-自由基、OH自由基的清除率,并对总还原能力进行测定。结果:13种苹果多酚含量在2.05~5.35 mg/g之间,对DPPH自由基清除能力最强,对NO₂^-自由基、O₂^-自由基和OH自由基的清除能力稍弱,总还原能力有一定差异,综合评价皮诺娃、长富二号、凯蜜欧、红盖露和玉华早富多酚抗氧化能力较强;在13种苹果中均检测出10种单体酚,鞣花酸、绿原酸、表儿茶素的含量相对较高,儿茶素、咖啡酸、原儿茶酸的含量相对较低;对10种单体酚进行抗氧化能力测定,发现原儿茶酸、表儿茶素、绿原酸综合抗氧化能力较强。结论:不同品种苹果多酚抗氧化能力与单体酚含量有相关性。

Evaluation of Antioxidant Activity of Polyphenols from Different Varieties Apples in Vitro

Objective:Thirteen varieties apples were chosen to evaluation the difference of polyphenols antioxidant activity by determining total polyphenols and free phenols antioxidant activity. Methods:Apple polyphenols were extracted using organic solvent with steam explosion-ultrasonic assisted. The antioxidant activity of total polyphenols and free phenols were studied with determining scavenging effect of DPPH· free radical,nitrogen oxide radical free radical(NO₂-·),hydroxyl free radical(·OH)and superoxide anion free radical(O₂-·),total reduction capacity was determined. Results:The polyphenols content of thirteen varieties apples were between 2.05 mg/g and 5.35 mg/g. Apple polyphenols of all varieties showed a strong scavenging effect of DPPH·,and a weak scavenging effect of NO₂-·,·OH and O₂-·,there was difference in total reduction capacity,pivona,nagafu 2,cameo,honggailu and yuhuazaofu showed the strongest antioxidant activity. A total of ten free phenols were determined in the thirteen apple polyphenols,the content of ellagic acid,chlorogenic acid and epicatechin were in a high level,and catechin,caffeic acid and protocatechic acid were in a low level. The antioxidant activities of ten free phenols were determined,and protocatechic acid,epicatechin and chlorogenic acid showed the strongest antioxidant activity. Conclusion:There had relationship between antioxidant activity and free phenols contents of apples polyphenols in different varieties.