Abstract

Carica papaya parts have been used traditionally to treat certain ailments. The aim of this study was to evaluate the antimicrobial potential of the total flavonoids of hydro alcoholic extract (TFHE) of the leaves of male Carica papaya. Fresh healthy male leaves of C. papaya were thoroughly rinsed in running tap water and dried on a disinfected platform under shade for 10 days. The leaves were then pulverized, percolated in 1 L methanol and the extracts examined for the presence of phytochemicals using standard protocols. These extracts were further studied for their antimicrobial potential against some test isolates: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans. Phytochemicals such as flavonoids, alkaloids, tannins, saponins, diterpines and cardiac glycosides were observed in the extracts. The extracts showed various degree of antimicrobial activities, with inhibitory zone diameters (IZDs) ranging from 13 mm – 24 mm (bacterial isolates) and 19 mm – 23 mm (fungal isolate). The extracts gave the highest IZD of 24 mm against E. coli at a concentration of 50 mg/ml and the least IZD of 13 mm against S. aureus at a concentration of 31.25 mg/ml. The extracts showed higher antifungal activity against the test fungal isolate compared to the standard fluconazole across the concentration gradient. These antimicrobial activities, especially antifungal activity greater than the standard drug observed in the methanolic leaves extracts could be due to the presence of potent secondary metabolites they harbour and these microbial activities decreases down the concentration gradient. The outcome of this study would make for further examination.