Comparative Review of the Antimicrobial Potential of Azadirachta Indica and Gliricidia Sepium

Abstract

Antimicrobial resistance has emerged as a major public health concern, creating an increasing need for alternative sources of antimicrobial agents. Medicinal plants represent an important source of structurally diverse bioactive compounds with potential antibacterial and antifungal properties. Azadirachta indica (neem) and Gliricidia sepium (Mexican lilac) are multipurpose plants that have traditionally been used for several purposes and have demonstrated antimicrobial activity against a variety of pathogenic microorganisms. This review summarizes the available evidence regarding the phytochemical composition and antimicrobial potential of A. indica and G. sepium, with particular emphasis on activity against Gram-positive and Gram-negative bacteria. Published studies indicate that neem contains bioactive constituents including azadirachtin, nimbidin, flavonoids and other secondary metabolites, while G. sepium contains flavonoids, phenols, alkaloids, tannins, saponins, glycosides and other potentially bioactive compounds. Extracts of both plants have demonstrated antibacterial activity against organisms including Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. However, antimicrobial efficacy varies according to plant part, extraction solvent, concentration, extraction method and susceptibility of the microorganism. The available evidence supports further investigation of these plants as potential sources of natural antimicrobial agents, particularly in the context of increasing antimicrobial resistance.