Phytochemical and in vitro antimicrobial potential of the leaf and stem of datura stramonium

Abstract

Datura stramonium is a widely grown plant and is well known for its potent pharmacological activities in medicine. This study was carried out to determine the phytochemical components of D. stramonium and its antimicrobial potential on three selected micro-organisms (Staphylococcus aeurus, Shigella dysenteria, and Salmonella typhi). The maceration method was employed for the methanol extraction of the leaf and stem. The extracts were subjected to qualitative and quantitative phytochemical screening. Agar well diffusion method was used to assay for the antibacterial property while micro broth dilution method was employed for microbial inhibitory concentration of the crude extracts of D. stramonium (leaf and stem). The qualitative phytochemical screening showed the presence of phenols, flavonoids, tannins, saponins, and alkaloids in both extracts. However, the quantitative phytochemical screening showed that the leaf extract was found to contain more phenols, flavonoids, tannins, saponins, and alkaloids than the stem extract. The extracts were observed not to exert inhibitory effects against S. aureus. The extracts showed inhibitory effects on S. typhi and S. dysentria with maximal activities at 100 mg/mL. However, leaf extract showed higher zone of inhibition of 27.00 ± 0.80 mm and 20.00 ± 0.82 mm against S. typhi and S. dysentria respectively than stem extract (10.00 ± 0.21 mm and 7.00 ± 0.28 mm). The leaf extract showed MBC of 200 and 250 mg/mL against S. dysenteria and S. typhi respectively while stem extract showed presence of bioactive secondary metabolites in the both extracts, which can be responsible for its antimicrobial activities against the tested microorganism. D. stramonium can serve as potential sources of antimicrobial agents.