Annona muricata: Comparative Assessment of the Antibacterial Activities of the Leaf and Stem Extracts against Multiple Antibiotic Resistant Clinical Isolates

Abstract

This study was conducted to determine the antibacterial effect of crude extracts of Annona muricata, comparing the leaf and stem bark extracts using the same extraction solvents. The bacteria isolates were obtained from the hospital. The isolates obtained are Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus mirabilis and Streptococcus pyogene; they were confirmed using standard techniques. Multiple antibiotic-resistant was confirmed in the isolates after antibiotic susceptibility testing. Extracts were prepared from the leaf and stem of A. muricata using ethanol, chloroform, cold water and hot water. The antibacterial activities of the crude extracts were assayed using the agar well diffusion method. The phytochemical screening revealed the presence of saponins, Tannins and flavonoid especially in the ethanol extracts of both leaf and stem part of the plant. All the extract showed varying degrees of antibacterial activities. Chloroform and Hot water rated best for antibacterial activities in this study. A. muricata stem hot water extract has zones of inhibition that ranges from 16.003 ± 0.009 mm to 1.000± 0.006 mm. A. muricata leaf hot water extract has antibacterial effect with zones ranging from 14.500± 0.009 mm to 1.000± 0.006 mm across the isolates. Cold water extracts recorded the lowest zones of inhibition from this study for the stem and Bark antibacterial activities. The stem of A. muricata has higher inhibitory effect on the test isolates compared to the leaf of      A. muricata.