Phytochemical screening, antimicrobial and antioxidant properties of assorted Carica papaya leaves in Ghana

The bioactive compounds of the leaves of Carica papaya; solo and solomix were extracted using ethanol and n-hexane, and investigated for the presence of secondary metabolites. Both ethanol and n-hexane extracts revealed the presence of alkaloids. Flavonoids, glycosides and saponins were present in only the ethanol extract whereas tannins were present in the n-hexane extract. The bioactivities of the leaf extracts were attributed to their phytochemical constituents. Antimicrobial activity of the extracts were determined against some human pathogenic bacteria and fungi such as Staphylococcus aureus, Escherichia coli, Streptococcus pneumoniae, Bacillus subtilis and Candida albicans using the agar well diffusion and broth dilution methods with the polar extract being more effective. The ethanol extract demonstrated a significant broad-spectrum antimicrobial activity against both gram-positive and gram-negative bacteria, with the highest activity having a zone of inhibition of 10 mm. Antioxidant activity was determined using the DPPH assay method and the absorbance measured using UV- visible spectrophotometer with ascorbic acid as control. The antioxidant activities of solo and solomix showed IC50 of 1.465x10-2 and 1.364x 10-2 respectively. This study demonstrates the efficacy of ethanolic leaf extracts of C. Papaya as an alternative antibiotic for the development of newer antibacterial agents.