CC BY 4.0 · Pharmaceutical Fronts 2022; 04(02): e89-e102
DOI: 10.1055/s-0042-1748031
Original Article

A New Colorimetric DPPH Radical Scavenging Activity Method: Comparison with Spectrophotometric Assay in Some Medicinal Plants Used in Moroccan Pharmacopoeia

Fatiha EL Babili
1   Henri Gaussen Botanical Garden, Paul Sabatier University Toulouse III, Toulouse, France
Clotilde Nigon
2   ENSAT, National Agronomic School of Toulouse, Castanet-Tolosan, France
Li Lacaze
3   Master in Engineering Sciences, Institut National Polytechnique of Nancy, Nancy Cedex, France
Juliette Millé
4   Faculty of Engineering Sciences, Paul Sabatier University, Toulouse Cedex, France
Anthony Masiala
4   Faculty of Engineering Sciences, Paul Sabatier University, Toulouse Cedex, France
Jennifer Simm
4   Faculty of Engineering Sciences, Paul Sabatier University, Toulouse Cedex, France
Virginie M. Lamade
5   Jean Jaures Toulouse University, (Toulouse) and Botanista – (Plaisance du Touch), France
Amal Ait El Haj
6   Laboratory of Pharmacognosy, Faculty of Medicine and Pharmacy, Hassan II University, Casablanca, Morocco
› Author Affiliations


Antioxidants in medicinal plants are particularly important in protecting against reactive oxygen species (ROS)-related diseases, such as heart and blood vessel disease, nervous system degeneration, and cancer. Because our bodies are not strong enough to completely neutralize ROS, we sometimes need antioxidant supplementation from herbs. There is ample empirical evidence in traditional pharmacopoeias. The antioxidant activities of plant drugs have long been spectrophotometrically measured with 2,2-diphenyl-1-picrylhydrazyl (DPPH). In this study, a new colorimetry DPPH radical scavenging activity method (validated to ICH standards) for some medicinal plants, used in Moroccan pharmacopoeia, was reported and made a comparison with spectrophotometric assay. In the method, a solution of DPPH is incubated in the presence of an antioxidant control (Trolox) or medicinal plant extracts in wells on a 96-well plate. After an appropriate reaction time, in the dark, the plate was scanned and images obtained were processed and analyzed by Image J software. This analysis will allow us to evaluate substance's antioxidant activity, almost in the same way as a spectrophotometric assay. The colorimetric DPPH method exhibited a strong correlation (R 2 > 0.95) with the conventional spectrophotometric DPPH method. The colorimetric DPPH method had excellent accuracy (103.81–105.47%), precision (1.051–10.85% RSD [relative standard deviation]), reproducibility (1.457% RSD), and robustness (1.05–1.38 F test). The developed DPPH test was easy, fast, low cost and reliable, and can be used for high-throughput assay for screening DPP-scavenging activity in herb medicines.

Publication History

Received: 24 November 2021

Accepted: 01 March 2022

Article published online:
09 July 2022

© 2022. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (

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