The antifungal effect of the biopreparation of Xenorhabdus budapestensis bacteria on some Candida species

Abstract

Introduction The prevalence of invasive fungal diseases shows an increasing trend. Due to the frequent but unprofessional usage of antifungal medications, the fungi show decreasing susceptibility towards these agents and this trend may lead to the emergence of resistant pathogens. There is a great need to develop antifungal medications with new mechanisms. One of these options is to apply proteins with natural antifungal effects. The objective was to measure the antifungal efficacy of Xenorhabdus budapestensis in vitro on clinical Candida species (Candida albicans, Candida lusitaniae, Candida krusei, Candida kefyr, Candida tropicalis, and Candida glabrata). Materials and methods: We defined the sensitivity of the Candida species towards antibiotics. We conducted agar diffusion tests with the cleaned biopreparation of X. budapestensis (100%) and its dilutions (80%, 60%, 40%, and 20%). Zones of inhibition were measured after 24, 48, and 96 hr. Results Most of the tested Candida species have shown sensitivity to the biopreparation and its 40% dilution. The area of the zones of inhibition did not decrease after several days. The most sensitive species was C. lusitaniae and the least sensitive was C. krusei. Conclusion We assume that the proteins produced by X. budapestensis have antifungal effect, as the area of the zones of inhibition did not change.