Use of an electrochemical method to evaluate the antioxidant activity of herb extracts from the Labiatae family

This paper describes a rapid method for the evaluation of the antioxidant activity of herb extracts from the Labiatae family. Herb methanolic extracts were analysed by using a flow injection (FI) system with an electrochemical detector equipped with a glassy carbon working electrode operating amperometrically at a potential of 0.5 V (vs. Ag/AgCl). Results obtained on extracts were compared to those obtained by using 2,2-diphenyl-l-picrylhydrazyl (DPPH-) test. A good correlation between the two methods was found (y= 1.3726x - 0.2266, r= 0.9856). The samples were also submitted to screening for their total phenol content.