In vitro antibacterial evaluation of Moringa oleifera against wound infecting bacteria: Phytochemical based approach

Abstract

Background: The rising trend of antibiotic resistance has made it essential to explore alternative antibacterial agents. Medicinal plants have been found to be a valuable source of natural antimicrobials, and this study sought to screen the antibacterial properties of methanolic extracts from leaves of medicinal plant Moringa oleifera against pathogenic bacteria Staphylococcus aureus (a Gram-positive bacterium) and Escherichia coli (a Gram-negative bacterium).

Methods: Clinical wound samples containing Gram-positive and Gram-negative bacteria were obtained, sub-cultured and identified using Gram staining and standard biochemical tests. Methanolic extracts of M. oleifera leaves were prepared and screened for phytochemicals using standard qualitative assays. Antibacterial activity was evaluated by agar well diffusion and broth microdilution methods to determine zones of inhibition and minimum inhibitory concentrations. Data was analyzed using GraphPad Prism software.

Results: Phytochemical analysis of M. oleifera methanolic leaf extract confirmed the presence of flavonoids, steroids and saponins, while quinones were absent. Bacterial isolates were identified as S. aureus (Gram-positive) and E. coli (Gram-negative) through morphological and biochemical tests. The extract exhibited concentration-dependent antibacterial activity, with negligible inhibition at lower concentrations and significant zones of inhibition at 1200 µL against both organisms. The minimum inhibitory concentration was determined to be as low as 300 µL, indicating effective antibacterial potential of the extract.

Conclusion: This study proves the antibacterial properties of M. oleifera and indicates that the plant can serve as sources of natural antibacterial for treating bacterial infections.