Validation of an alternative quantitative method for determination of antioxidant potential in Rosmarinus ofcinalis L. and Chilli pepper

Abstract

We provide proof-of-concept for the innovative method of 2,6-dichloroindophenol (DCPIP) for measuring the antioxidant activity of plant extracts. Antioxidant content can be determined using the standard DCPIP test and compare the results with the DPPH results as conventional method. DCPIP operates on the premise that the deep blue color of the oxidized dye is reduced to an invisible solution. Ascorbic acid’s antioxidant activity was measured by DCPIP at different times (from 1 to 60 min) and was concentration-dependent, with the maximum activity being at 400 g/mL. In addition, when compared to other incubation durations, the ascorbic acid standard, a natural antioxidant, gave the maximum activity within the first five minutes of incubation with DCPIP. DCPIP is a marker of antioxidant activity both against vitamin C and plant extracts. The DCPIP approach is quick and unaffected by pH variation. The stability of the DCPIP reagent over time (5 and 30 min) and color reduction by ascorbic acid as a natural antioxidant standard were demonstrated using a straightforward and quick method.