Extraction and antioxidant activities of total flavonoids in green tea from 3 different regions in Guangxi
In order to study the extraction process and antioxidant activity of total flavonoids in green tea from 3 different regions in Guangxi,using 3 kinds of green tea from different regions of Guangxi(northern Guangxi,central Guangxi,southern Guangxi)as raw materials,the total flavonoids were extracted by microwave-assisted extraction method.On the basis of single factor tests,the microwave-assisted extraction conditions of total flavonoids in 3 kinds of green tea were optimized by orthogonal tests,and their antioxidant activities were evaluated according to 1,1-diphenyl-2-picrylhydrazyl(DPPH)and hydroxyl radicals scavenging ability.The results showed that the optimum extraction conditions of green tea in northern Guangxi was ethanol volume fraction 60%,solid and liquid ratio 1:60(g∶mL),and microwave power 600 W.The optimum extraction conditions of green tea in central Guangxi were ethanol volume fraction 50%,solid and liquid ratio 1∶50(g∶mL),and microwave power 500 W.The optimum extrac-tion conditions of green tea in southern Guangxi were ethanol volume fraction 50%,solid and liquid ratio 1∶50(g∶mL),and microwave power 600 W.Under the optimized conditions,the yields of total flavonoids were(12.29±0.56)%,(12.51±0.39)%and(14.32±0.42)%,respectively.The results of in vitro antioxidant tests showed that the total flavonoids in 3 kinds of green tea had stronger DPPH radicals scavenging ability and certain hydroxyl radicals scavenging ability.
green teaflavonoidsextractionorthogonal experimentantioxidant activity
万方数据
维普
