Antioxidant Activity of Different Solvent Extracts of Yunnan Pu-erh Tea
Antioxidant activity of different solvent extracts of Yunnan Pu-erh tea was studied in this paper.The scavenging ability of DPPH free radical,OH-free radical,superoxide anion free radical and nitrite of different solvent extracts of Pu-erh tea,as well as reducing power were investigated by using rutin and ascorbic acid(vitamin C)as the control.Results suggested that the different solvent extracts of Pu-erh had significant scavenging effects on the DPPH free radical,OH-free radical and superoxide anion free radical.All kinds of extracts had significant reducing power,but had no significant effects on nitrite.The antioxidant activity of different solvent extracts of Pu-erh had positive correlation with their concentrations.The scavenging effects of ethanol sedimentation segment,n-butanol extract,ethanol extract,ethanol soluted segment on the DPPH free radical were stronger than that of rutin control at the same concentration.In addition,the water extract,ethanol sedimentation segment and ethanol soluted segment had stronger ability of scavenging OH-free radical,but lower than that of Vc control.Acetal extract had stronger scavenging effects on superoxide anion free radical and nitrite and also had stronger reducing power.