Phytochemical screening and antioxidant activity of Vitex agnus-castus L.

Abstract

This research is dedicated to investigating the antioxidant potential and phytochemical composition of three distinct extracts derived from Vitex agnus-castus L. These extracts, prepared through aqueous (EXA), ethanolic (EXE), and methanolic (EXM) maceration, were chosen based on prior assessments of total polyphenol content in extracts obtained from five solvents with differing polarities: water, methanol, ethanol, acetone, and butanol. The study initiated with a comprehensive phytochemical analysis focusing on the determination of total polyphenols and flavonoids. The quantification of total polyphenols was carried out using the Folin–Ciocalteu method, while the AlCl3 method was employed to assess flavonoids. In evaluating the in vitro antioxidant activity, we employed two well-established methods, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric-reducing antioxidant power (FRAP). The preliminary tests, gauging the efficacy of solvents, demonstrated that the order of optimal solvent selection was as follows: aqueous, methanolic, ethanolic, butanolic, and acetone. Consequently, the first three solvents were chosen for the preparation of the extracts. The phytochemical analysis unveiled that EXA exhibited the highest total polyphenol content, with an impressive value of 126.84 ± 1.24 mg EAG/g extract, whereas EXE exhibited the lowest concentration of total polyphenols, measuring at 117.26 ± 0.18 mg EAG/g extract. In contrast, EXM showcased a notably high flavonoid content, registering at 33.65 ± 1.04 mg EQ/g extract, while EXA displayed a comparatively lower flavonoid content at 14.93 ± 0.14 mg EQ/g extract. When assessing antioxidant properties, EXA emerged as the most potent against both DPPH and FRAP, recording values of 78.94 ± 1.84 and 203.27 ± 0.17 μg/ml, respectively. In contrast, the ethanolic extract exhibited relatively lower antioxidant activity, with values of 204.16 ± 1.87 μg/ml for DPPH and 307.10 ± 1.15 μg/ml for FRAP.

Keywords

• vitex agnus-castus
• polyphenols
• antioxidant activity
• phytochemical screening