Shalaby, Emad AAboul‑Enein, Ahmed MSayed, Nadia MSaid, Mohamed EHussain, Ahmed RShehata, Yousef MSayed, Salsabil R Saeed, Marwa M. HHanafy, Eman A2023-10-082023-10-082023-09https://doi.org/10.1007/s11696-023-03076-9http://repository.msa.edu.eg/xmlui/handle/123456789/5741We 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 diferent 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 frst fve 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 unafected 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.enRosmarinus ofcinalis L. · Chilli pepper · Radical scavenging activity · Antioxidant methods · DCPIP methodArticlehttps://doi.org/10.1007/s11696-023-03076-9