Antibacterial activity of aqueous and methanol extracts of <i>Jatropha tanjorensis</i> and <i>Adansonia digitata</i> against selected clinical bacteria pathogens

Abstract

The powdered plant parts (bark, stem, and leaf) were extracted with methanol, and cold and hot water using the maceration method. A modified agar well diffusion technique was used for the assessment of the antibacterial activities of the aqueous and methanol extracts of J. tanjorensis and A. digitata. The methanol extract of A. digitata bark gave the highest yield of 75 % while the lowest yield was observed with the cold water extract of A. digitata bark of 33 %. The phytochemical screening showed an abundance of alkaloids, terpernoids, saponins, flavonoids, tannin, glycoside, and phenol. The bark, leaf, and stem of J. tanjorensis and A. digitata showed varying degrees of antibacterial activities. against the Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Proteus spp, and Klebsiella spp) and Gram-positive bacteria (Staphylococcus aureus, Streptococcus pyogenes and Streptococcus pneumonia). The bark, stem, and leaf extract of J. tanjorenis significantly (p < 0.05) inhibited all the pathogens except P. aeruginosa and S. aureus.The result of the minimum bactericidal concentration MBC for the combined extracts of A. digitata and J. tanjorenis subfractions showed that the extracts have greater antibacterial activities at concentrations not lesser than 100 mg/ml. Thus, J. tanjorensis and A. digitata could be used as potent herbal remedies to mitigate the adverse effects of Gram-negative and positive clinical pathogens. Thus, the aim of this study was to evaluate the antibacterial activity of aqueous and methanol extracts of Jatropha tanjorensis and Adansonia digitata against selected Clinical bacteria pathogens.