Study on antioxidant activity of different polar extracts of coix seed
YU Qiaorong1,2 HUANG Suoyi2,3
1.College of Pharmacy, Guangxi University of Chinese Medicine, Guangxi Zhuang Autonomous Region, Nanning 530001, China;
2.Guangxi Colleges and Universities Key Laboratory of the Characteristics of Ethnic Medicine of the Youjiang Valley, Youjiang Medical University for Nationalities, Guangxi Zhuang Autonomous Region, Baise 533000, China;
3.College of Pharmacy, Youjiang Medical University for Nationalities, Guangxi Zhuang Autonomous Region, Baise 533000, China
Abstract:Objective To study the antioxidant activity of different polar extracts of coicis, and screen for optimum antioxidant active polarity segment. Methods Coix seed was extracted using reflux method by 95% ethanol. Then the concentrated ethanol extract was partitioned between petroleum ether, chloroform, n-butanol and water, respectively, which gave the oil ether part, chloroform part, n-butanol part and water part. The antioxidant activity of different polar regions was studied by determining the scavenging ability of ABTS+ free radicals and DPPH free radicals and the ability of restoring Fe3+, and compared with BHT. Results Different polar extracts had different degrees of clearance ability of DPPH free radicals and ABTS+ free radicals, and had certain reduction capabilities. The order of scavenging capacity of four extracts to ABTS+ free radicals was: water part > n-butanol part > chloroform part > petroleum ether part. The order of scavenging capacity of four extraction sites to DPPH radical was: n-butanol part > water part > chloroform part > petroleum ether part. The order of the capacity of the four extraction sites to the reduction ability of Fe3+ was: water part > n-butanol part > petroleum ether part > chloroform part. The scavenging free radical ability and total reduction ability were lower than the positive control BHT. Conclusion The different polar extracts of Coix seed have free radical scavenging ability and antioxidant effects. The water part has the best ability to scavenge ABTS+ free radical, the n-butanol fraction has the best ability to scavenge DPPH free radical, and the water site has the best ability to restore Fe3+.