Evaluation of the Antifungal Activity of Azadirachta indica Leaf Extracts and Fractions against Clinically Resistant Fungal Isolates

Abstract

The emergence of fungal resistance to antifungal agents is a significant concern, it leads to treatment failure and poor clinical outcomes. Fungal infections pose significant concern to human health, agriculture and the environment. Hence the need for alternative antifungal agents to combat the existing problem. This study aims to investigate the antifungal property of Azadirachta indica on resistant fungal isolate such as Candida albican and Aspergillus niger capable of causing infections in humans and animals. The sample collection is from the botanical garden of department of Pharmacognosy and Traditional Medicine at Nnamdi Azikiwe University, Awka. The leaves were finely ground into powder, and the active component was isolated through extraction and fractionation. To assess their efficacy against the test microorganisms, the crude extract and fractions underwent Agar Well Diffusion assays, measuring the zones of inhibition. The extracts and fractions showing activity had their Minimum Inhibitory Concentrations determined by broth dilution method. Out of the fractions tested, all the fractions demonstrated activity against both A. niger and Candida albicans. The crude extract and all the fractions showed good antifungal activities against A. niger with IZD ranging between 2 to 5.5 mm. Minimum inhibitory concentrations ranged from 25 to 200 mg/ml for both A. niger and C. albicans. It is concluded that A. indica has antifungal activity against A. niger and C. albicans. Also, F9 exhibited the highest inhibition zone of 5.5±0 mm and MIC of 25 mg/mL against A. niger.