Studies on Hypoglycemic Activities of Chinese Bayberry Anthocyanins in Vitro
Inhibition and kinetics of α-amylase and α-glucosidase,as well as glucose uptake and consumption of human hepatoma HepG2 cell were investigated to assess the in vitro glucose-lowering effect of anthocyanin extract of Chinese bayberry(Myrica rubra Sieb.et Zucc.)fruit(AECBF).The results showed that AECBF exhibited potently inhibitory ef-fect on α-amylase and α-glucosidase,with IC50 value of 22.54 μg/mL and 3.51 μg/mL,respectively.The results of enzy-matic inhibition kinetics indicated that both α-amylase and α-glucosidase gave a mixed-type inhibition,and competitive inhibition was predominant in α-amylase while uncompetitive inhibition in α-glucosidase.In addition,no obvious cyto-toxicity of HepG2 was observed after treated with AECBF for 24 h,ranged from 0.1 μg/mL to 10 μg/mL(P>0.05),and glucose uptake and consumption of HepG2 cells were increased notably after treatment with 1 μg/mL to 5 μg/mL for 24 h(P<0.05).Compared to normal control,AECBF-treated HepG2 cells gained the maximum glucose uptake and glucose consumption at 2 μg/mL and 5 μg/mL,respectively,corresponding to an increase by 72% and 44% ,respectively.These results indicated that Chinese bayberry anthocyanin exhibits potent in vitro hypoglycemic activities.
bayberry fruitanthocyaninsstarch-digesting enzymesinhibition kineticsglucose uptake and consumption