Etude phytochimique et évaluation de l’activité antioxydante et antibactÈrienne des extraits de Cymbopogon schoenanthus (L.) Spreng.

Abstract

This work was devoted to the study of the phytochemistry and evaluation of the antioxidant and antibacterial activities of the hydromethanolic extracts of Cymbopogon schoenanthus (L). Spreng. which is a medicinal plant known as "El Lamad". Hydromethanolic extracts were obtained by Soxhlet (Ex S) and maceration (Ex M) with yields of 5.61% and 5.03%, respectively. Quantitative estimation of total polyphenols and flavonoids showed that both extracts were rich in these compounds. Results showed that the highest amounts of total polyphenols and flavonoids were found in Ex S with 91.16±3.97μg EAG/mg Ex and 7.75±0.49μg EQ/mg Ex, respectively. In vitro evaluation of the antioxidant activity of the extracts was carried out using four methods: DPPH test, ABTS test, reducing power and total antioxidant capacity (CAT). The results showed that both extracts had a powerful antioxidant capacity, with the highest antiradical effect in Ex S, while Ex M had the best reducing power. Evaluation of the antibacterial activity of the extracts by the diffusion method in solid medium showed low antibacterial activity against the tested strains.