Comparative Evaluation of Kratok Bean (Phaseolus lunatus L.) Flour and Boiled Extract as Alternative Media for Candida albicans Growth

Abstract

Candida albicans is an opportunistic fungal pathogen and the principal causative agent of candidiasis, whose laboratory identification frequently relies on selective culture media most notably Potato Dextrose Agar (PDA) at considerable cost. As a practical alternative, this study evaluated the potential of kratok bean (Phaseolus lunatus L.) seeds processed as flour-based agar (FBKA) and boiled-extract agar (BEKA) for supporting C. albicans growth. A pure laboratory experimental design was employed, comparing macroscopic and microscopic colonial characteristics between PDA (control) and both alternative media following 72 hours of incubation at 37°C, with three independent replicates (n = 3). Both alternative media supported C. albicans growth, producing colonies with a cream to yellowish coloration, a characteristic yeast odor, and a convex surface morphology by day 3. Microscopic examination via the germ tube test on both alternative media confirmed pseudohyphal formation. Kruskal–Wallis analysis revealed significant inter-media differences in colony diameter on day 3 (H = 7.200; p = 0.027). Post-hoc Dunn's test demonstrated that BEKA produced colonies of ≤3 mm at day 3, statistically comparable to PDA (z = 1.342; p = 0.179, ns), whereas FBKA yielded colonies of ≤2 mm and differed significantly from PDA (z = 2.683; p = 0.007). These findings indicate that the boiled-extract medium outperforms the flour-based formulation and warrants consideration as an efficient, cost-effective substitute for C. albicans culture in resource-limited laboratory settings.