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

Abstract

Cladosporium spp. filamentous fungi are black or dematiaceous. They are important food contaminants, causing product loss in the food industry and health problems. Thus, several studies look for ways to control the growth of such organisms, and thus, studies on the action of natural products with antifungal activity has been increasing more and more, given the weaknesses of the use of synthetics. Among the natural products, the use of terpenes is highlighted, as they are widely distributed compounds in nature and endowed with potential antifungal activity. Therefore, this study investigated the possible potential antifungal geraniol a monoterpene alcohol type, compared to strains of C. carrioni LM 227 and URM 5109, C. oxysporum URM 5234 and URM 5412, C. cladosporioides URM 5737 and URM 6246. To this, it was determined the minimum inhibitory concentration (MIC) and minimum fungicidal (MFC) of geraniol by microdilution in RPMI 1640. After this, the effects of different concentrations of geraniol were analyzed (1/2MIC and 2xMIC) of the mycelial growth, production and conidial germination. The MIC results obtained were 256ìg/ml for the strain of C. carrioni URM 5109 and 512 ug/ml for the others strains. The results are shown MFC equal to or greater than the MIC in all strains esaiadas. In the experiments for the evaluation of geraniol interference in mycelial growth, production and germination of fungal conidia, it was observed that geraniol inhibited significantly (p <0.05) dry mycelial mass production and spore production of the strains C. cladosporioides URM 5737, C. carrioni LM 227 and C. oxysporum URM 5234, the concentrations of MIC and 2xMIC. All tested strains had conidia germination significantly inhibited (p <0.05) at different concentrations (1/2MIC, MIC and 2xMIC). Thus, the monoterpene geraniol showed satisfactory antifungal front strains of Cladosporium spp., right, stands out as a promising natural alternative for use in food in industries.