Análise dos efeitos inibitórios de citronelol sobre o crescimento de fungos contaminantes do gênero Cladosporium.

Abstract

The genre Cladosporium spp. is comprises of a group of filamentous fungi characteristically dark. They are important contaminating agents for food producers industries, which suffer with the loss of its products by colonization of these fungi. The facts that they are potential contaminants make them relevant to researchers that work in studies that look for drugs to control fungal growth. Within this theme, the study of the action of natural products with antifungal activity is growing more and more. And among the natural products with this potential, the monoterpenes receive important focus for its proven antifungal action. Therefore, in this study it was investigated the antifungal activity of the monoterpene citronellol against strains of Cladosporium oxysporum URM 5412 and 5234 and Cladosporium cladosporioides URM 5737 and 6246. For this purpose, were determined the minimum inhibitory concentrations (MIC) and minimum fungicidal (MFC) of citronellol, and what effects of various concentrations (1/2 MIC, MIC and 2xMIC) on the morphological characteristics of mycelial growth and germination of fungal conidia. The results of the MIC were 256 μg/mL for the strain C. cladosporioides URM 5737 and 512 μg/mL for strains C. oxysporum URM 5234, C. oxysporum URM 5412 and C. cladosporioides URM 6246. The results of MFC were higher than MIC, being 512 μg/mL for strain C. cladosporioides URM 5737, 1024 μg/mL for strains C. oxysporum URM 5412 and C. cladosporioides URM 6246 and 2048 μg/mL for strain C. oxysporum URM 5234. In trials conducted to evaluate the effects of citronelol against the mycelial growth and spore germination of strains C. oxysporum URM 5234 and C. cladosporioides URM 5737, it was observed that both strains had their morphological characteristics inhibited by the different concentrations tested (p<0,05). Citronellol showed significant antifungal activity on the strains of Cladosporium spp, and thereby, emerging as a promising active constituent for the application of sanitizers in food in industries. However, before its utilization, are necessary others specific studies to soften its sharp aroma, which can alter the sensory characteristics.