ANTIBACTERIAL ACTIVITY OF CARICA PAPAYA LEAF EXTRACTS ON SOME BACTERIA ISOLATED FROM WOUNDS OF PATIENTS ATTENDING THE JOS UNIVERSITY TEACHING HOSPITAL (JUTH)

Dafur Gayus Sale*, Dawurung Ayuba Bulus and Dafur Bala Sale

ABSTRACT

The antibacterial activity of the aqueous and methanolic leaf extracts of Carica papaya (pawpaw) was investigated using the agar diffusion method. The test organisms used were Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus pyogenes. Gentamycin at concentration of 4 mg/ml was used as a standard drug (positive control) whereas distilled water was used as the negative control. The aqueous extract did not show antibacterial activity against any of the test organisms. The methanolic extract had antibacterial activity against Proteus mirabilis only, at concentrations of 700 mg/ml, 350 mg/ml and 175 mg/ml. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) values recorded were 87.5 mg/ml and 350 mg/ml respectively. Phytochemical screening showed the presence of alkaloids, tannins and steroids in the methanolic extract, whereas only carbohydrates and steroids were detected in the aqueous extract. Despite the insignificant activity of the extracts, these results suggest that Carica papaya leaves could still be used in the treatment of wound infections caused be Proteus mirabilis. It might be that the constituents of the leaves were greatly affected by the extraction procedures employed, hence the need for more investigations using other extraction methods.

Keywords: Antibacterial activity, Carica papaya, leaf extracts, bacteria, wounds, patients.