Abstract:This manuscript optimized the extraction technologies and investigated the antioxidant activities of the total flavonoids from Feijoa sellowiana leaves.The results determined that the optimum parameters of extraction process as follows: the extraction temperature 40 ℃,the ratio of sample to extraction solution 1:30,the extraction time 50 min and the concentration methyl alcohol 70%.With the optimum extraction parameters,the total flavonoids contents with three reiterations achieved at 46.89 mg/gFW,44.51 mg/gFW and 48.27mg/gFW,respectively.In addition,half-inhibitory concentration IC50 was used to evaluate antioxidant activities of total flavonoids from Feijoa leaves.The capability of inhibiting lipid peroxidation(IC500.275 mg/mL) and scavenging effects on DPPH freedom radical(IC500.798 mg/mL) of total flavonoids extracts were stronger than the corresponding values of ascorbic acid(IC500.643 mg/mL and IC500.917 mg/mL).However,the scavenging effects on superoxide anion(IC500.774 mg/mL) and hydroxyl freedom radical(IC500.278 mg/mL) were weaker than that of ascorbic acid(IC500.537 mg/mL and IC500.275 mg/mL).
