In-vitro antibiogram of Bryophyllum pinnatum extracts with or without potassium aluminum sulphate against some pathogenic bacteria
Lawrence O Amadi, Miriam C Osiagor, Charity R Christopher
In-vitro antibiogram of Bryophyllum pinnatum leaf extracts with or without potassium aluminium sulphate (Alum) were investigated by disc diffusion method (DDM) and agar well diffusion method (AWDM) respectively. The leaves of B. pinnatum was dried in an oven at 45oC for 14days and pulverized with a blender. Alum, methanolic and aqueous leaf extracts of B. pinnatum were reconstituted in 100ml of sterile distilled water respectively. Antibacterial activity of different percentage concentrations (0.5, 1.0, 1.5 and 2.0% (w/v) of the leaf extracts with or without alum were evaluated by measuring diameter of inhibition zones (DIZs) respectively. Aqueous leaf extract with alum had the highest mean DIZ values which ranged from 17.5-29.5mm, methanolic leaf extract with alum 0-22.0mm and leaf extracts without alum 0-8.5mm at 2.0% concentrations respectively. There were progressive increases in DIZs against test bacteria (Bacillus subtilis, Klebsiella pneumoniae, Staphylococcus aureus and Salmonella typhi) with increasing concentrations of leaf extracts with and without alum although certain discrepancies were observed with aqueous leaf extract, methanolic leaf extract with and without alum respectively. Demonstration of antibacterial activity on Gram negative and positive test bacteria by leaf extracts with or without alum suggests broad spectrum activity. Thus, this study reveals that the potassium aluminum sulphate (Alum) potentiated the inhibitory activity of B. pinnatum leaf extracts and should be used topically or otherwise as a novel antibacterial agent to combat infections caused by these pathogens.