Determination of total flavonoids and its antioxidant activity in the exocarp of Aronia melanocarpa

摘要

As a kind of berry food rich in flavonoids,the determination method of total flavonoids content of Aronia melanocarpa is of great significance.This paper compares the applicability of NaNO_(2)-Al(NO_(3))_(3)-NaOH colorimetry and AlCl_(3)colorimetry to total flavonoids content of the exocarp of Aronia melanocarpa by Ultraviolet-visible Spectrophotometry.At the same time,we determined hydroxyl radical(OH·-)inhibition rate,superoxide anion radical(O_(2)·-)inhibition rate and 1,1-diphenyl-2-picrylhydrazyl radical free radical(DPPH·)scavenging rate of total flavonoids extracted from Aronia melanocarpa.It is found that AlCl_(3)colorimetry has good repeatability,precision,and accuracy.The method is suitable for the determination of total flavonoids in the exocarp of Aronia melanocarpa.Thus,by the established method the content of total flavonoids in the exocarp of Aronia melanocarpa was determined as high as(36.711±0.034)mg/g.The results of antioxidant activity showed superoxide anion radical scavenging ability,hydroxyl radical scavenging ability and DPPH radical scavenging ability of the total flavonoids extract reached 45.33%,87.87%and 98.05%,respectively,indicating that it had good antioxidant activity.