Antibacterial Activity and Phytochemical Screening of Carica papaya on some Enteric Bacterial Isolates of Public Health Importance

Abstract

The study was carried out to determine the antimicrobial activities of Carica papaya and its major antimicrobial constituents (phytochemicals). The aqueous and ethanol extracts from the leaves and stem back of these plants were tested using well Diffusion method for their antimicrobial activity against some members of Enterobacteriales family isolated from diarrheic stool sample (Escherichia coli, Shigella spp, Salmonella typhi and Pseudomonas aeruginosa). Statistical analysis of the result shows that both the extracts demonstrated higher activities against bacteria tested, with the average zone of inhibition of 15.44mm, 14.78mm, 12.92mm and 11.31mm for Shigella, Escherichia coli, Salmonella typhi and Pseudomonas aeruginosa respectively. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the extracts ranges between 12.5–100 mg/ml. Preliminary phytochemical analyses showed that the extracts contain alkaloids, tannins, terpenoids, anthraquinones, reducing sugar, amino acid, flavonoids, saponins, glycosides and phenols. Demonstration of antibacterial activity against the test isolates is an indication that there is possibility of sourcing alternative antibiotic substances in these plants for the production of newer antibacterial agents.