Antibacterial Activity of Adansonia digitata Leaf Extract against Gastrointestinal Bacterial Isolates

Adansonia digitata (A. digitata), also known as baobab, is a traditional medicinal plant that has been shown to possess antibacterial properties. This study was carried out to determine the antibacterial activity of aqueous and ethanolic extracts of A. digitata leaves against Escherichia coli and Staphylococcus aureus isolated from the human gastrointestinal tract (GIT). The leaf extract was screened for its phytochemical constituents to evaluate the availability of active compounds. The leaves extract was subjected to antibacterial analysis by agar well diffusion method using different concentrations. The phytochemical screening revealed the presence of alkaloids, saponins, phenol, tannins and steroids. Ethanolic leaf extracts exhibited inhibitory effects against S. aureus (19±1.78 to 9.6±2.09mm) and E. coli (18.4±1.19 to 11.4±1.07mm) across concentrations of 100 to 12.5mg/ml. Aqueous extracts also showed activity with zones ranging from 13.5±2.00 to 6.3±0.3mm for S. aureus and 15.1±1.60 to 7.00±1.04mm for E. coli. The ethanolic leaf extract inhibited the growth of E. coli and S. aureus at a concentration of 12.5-50mg/ml with a minimum bactericidal concentration (MBC) at 25-50mg/ml. The aqueous leaves extract inhibited the growth of S. aureus and E. coli at a concentration of 25-100mg/ml with an MBC of 50-100mg/ml. The results indicate that Adansonia digitata ethanolic leaf extract has a higher level of bioactive components contributing to its strong antibacterial effect against the pathogenic bacteria. The antibacterial activity of Adansonia digitata leaves extract against E. coli and S. aureus. These findings support the need for standardised methods of extraction and processing to maintain consistency. Further research, including clinical studies and mechanistic evaluation, is warranted.