Antibacterial activities of leaf extracts of <i>Brassica oleracae</i> var. <i>capitata</i>. (Brassicaceae) against multi-drug resistant clinical isolates in Maiduguri

Abstract

Brassica oleracae var. C. green cabbage, a herbaceous biennial plant with leaves that form a compact head, is an edible vegetable used historically as a medicinal herb for a variety of purported health benefits. The aim of the study was to evaluate the antibacterial activities of ethanolic and methanolic leaf extracts of Brassica oleracae var. C. against clinical isolates of pathogenic bacteria (S. aureus, E. coli, K. pneumonia and P. aeruginosa) by agar well diffusion method. The extraction was carried out by cold marceration and qualitative phytochemical analysis was conducted. The phytochemical screening revealed the presence of cardiac glycosides, flavonoids, tannins, terpenoids and reducing sugars. The ethanolic and methanolic extracts demonstrated a concentration-dependent antibacterial activity against S.aureus, E.coli, and P. aeruginosa. In conclusion, the ethanolic and methanolic extracts of B. oleracae demonstrated antibacterial activities and these findings could contribute to effective use of the plant.

Keywords: Antibacterial, Brassica oleracae, Clinical isolates, Multi-drug resistant, Phytochemical constituents