Effect of Tualang Honey on Candida albicans Biofilms

Abstract

Candida albicans is the most common fungal pathogen associated with fungal biofilm, capable of causing superficial mucosal infections and life-threatening systemic infections in humans. This study was conducted to evaluate the in vitro inhibitory activity of Tualang honey on early-phase and mature (established) biofilms of C. albicans. The kinetic profiles of biofilms were assessed using the XTT reduction assay and field-emission scanning electron microscopy (FESEM). The minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) of Tualang honey were determined through a two-fold serial dilution method, with concentrations ranging from 5% to 80% (w/v). The XTT assay and FESEM were also utilised to evaluate the inhibitory effects of Tualang honey on both early-phase and established biofilms of C. albicans. The early and maturation phases of biofilms were attained after 4 to 12 hours and 48 to 72 hours, respectively. The lowest MIC value of Tualang honey against C. albicans was 80% (w/v). The MFC was undetermined within the tested concentrations. Tualang honey exerted its effect on biofilms by slowing the formation of early-phase biofilms and reducing the size of established biofilms by disintegrating their structures at high concentrations. The FESEM results indicated that this honey caused roughening of the cell surfaces and a decrease in biofilm biomass. The findings from this study suggest that Tualang honey, when applied at a high concentration of 80% (w/v), exhibits a fungistatic-like effect by inhibiting the proliferation of adherent fungal cells and disrupting the structural integrity and stability of biofilms, thereby hindering their further development and maturation.