Antibacterial activity of Annona muricata leaves’ extracts

The phenomenon of multidrug-resistant pathogens has increasingly become a cause for serious concern with regard to both nosocomial and community-acquired infections. Plants have been useful to man not only for food, shelter, and clothing but also for their use for ornamentation and health care. Annona muricata belongs to the family of Annonaceae and commonly known as Soursop. It is used in traditional medicine in many countries to cure various ailments and diseases. This study investigated in vitro antibacterial activity of Annona muricata Linn. leaves extracts against Escherichia coli, Staphyococcus aureus, Acenobacter baumanni, Moraxella catarrhalis and Enteroccocus faecium. Antibacterial assay was performed by Agar well diffusion method in Mueller Hinton Agar plates. N-hexane, methanol and water were used as solvents for extraction while Chloramphenicol (30 µg) served as control. The result of the present study revealed that n-hexane A. muricata extract exhibited highest inhibitory action against Enterococcus faecium (20.67 mm) and Acinetobacter baumarii (21.34 mm) when compared with all the treatments including chloramphenicol (16.65 mm; 15.35 mm respectively) . The result also showed that methanol, aqueous and n-hexane extracts had highest zone of inhibitions against Escherichia coli (25.76 mm), Staphylococcus aureus (18.65 mm) and Moraxella catarrhalis (18.65 mm) respectively. It was discovered in this study that Annona muricata leaves’ extracts possessed activity against the tested bacteria responsible for the most common bacterial diseases with n-hexane extract showing significant inhibitory action against both Gram-positive and Gram-negative bacteria. The activity of Annona muricata leaves depended greatly on the solvent of extraction. The result recommends Annona muricata leaves as potential new effective drug for bacterial infections including multi-drug resistant bacteria and further studies should be carried out to determine its mechanism of actions.