Article

Evaluation of the Antimicrobial and Phytochemical Properties of Annona Muricata L. (Soursop)

Abstract

The ethanol, methanol and aqueous extracts, of dried leaves, bark root and mixture of bark, root and leaves of Annona muricata l (soursop) were screened for its phytochemical constituents and invitro antibacterial properties on the following hospital isolates: Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli and Salmonella typhi. Methods: The well in agar and disc diffusion techniques were used to assay for the antimicrobial properties and the result showed that the ethanol and methanol extracts of the leaf at different concentrations inhibited the growth of all the organisms. The aqueous extracts of the leaf inhibited the growth of only the E. coli. The ethanol and methanol extracts of the root inhibited the growth of S. pyogenes, and E. coli. The bark extract inhibited the growth of S. aureus, Salmonella typhi,and E. coil. The mixture of the bark, root and leaf extract inhibited the growth of S. pyogenes only. Results: The Minimum inhibitory Concentration (MIC) of the ethanol, methanol and aqueous extracts of the bark, root, leaf and the mixture of the bark, leaf and root determined by the tube dilution method falls within the range of 65.25mg/mI, 125mg/ml to 250mg/ml accordingly for the sensitive organisms. The Minimum Bactericidal Concentration (MBC) of both the ethanol and methanol extracts was found to be between 250mg/ml and 125mg/mI for some of the organisms investigated. No MBC was recorded for aqueous extracts of all the sensitive isolates. The phytochemical screening revealed the presence of saponin, anthroaquinone, anthranoid, phenol. Alkaloid, tannin, Phylobatannin, and cardiac glycosides. Conclusion: The alcoholic extracts retained the antimicrobial properties of the plant more than the aqueous extract.

Keywords: Annona muricata l. (soursop), Phytochemical analysis, S. aureus, E. coli, S. pyogenes, S.typhi.