Antifungal Effect of Kaffir Lime Leaf Extract on Selected Fungal Species of Pathogenic Otomycosis in in vitro Culture Medium

Background: Kaffir lime (Citrus hystrix D.C) has been used for a long time in agricultural and alternative medicine. Kaffir lime leaf (KLL) had been proved effective against certain fungi that could infect human body. Objective: To study the antifungal effect of KLL extracts on Aspergillus niger and Candida albicans. Methods: This is a laboratory-controlled prospective study conducted in Universiti Sains Malaysia. KLL was extracted with 70% ethanol and aqueous via Soxhlet extraction method. The concentrated extract then freeze dried to obtain powdered form which was diluted to establish five different concentrations of 50 g/ml, 25 g/ml, 12.5 g/ml, 6.25 g/ml and 3.125 g/ml. Sabouraud Dextrose Agar (SDA) lawned with tested fungal isolates were inoculated with the extracts using well-diffusion method. Zone of inhibition was measured followed by minimum inhibitory concentration (MIC). Results: There were presences of zone of inhibition for both aqueous and alcohol KLL extracts on Aspergillus niger and Candida albicans growth. KLL aqueous extract have bigger mean of inhibition as compare to alcohol extract against Aspergillus niger. In contrast, KLL alcohol extract have bigger mean of inhibition as compare to aqueous extract against Candida albicans. The MIC of KLL aqueous extract against Candida albicans was 12.02 g/ml, alcohol extract against Candida albicans was 10.23 g/ml, KLL aqueous extract against Aspergillus niger was 47.86 g/ml and alcohol extract against Aspergillus niger was 48.97 g/ml. Conclusion: KLL has significant antifungal effect towards pathogenic fungi causing otomycosis, particularly Aspergillus niger and Candida albicans.