Identification of the airborne fungal microbiota in a fruit pulp industry and antifungal susceptibility to terpenes

Abstract

Airborne fungi are important food contaminants and spoiling agents, especially in fruits and their derivatives. This study aimed at identifying the main fungi in the airborne microbiota in a fruit pulp industry, located in Paraíba State, and to investigate the antifungal action of terpenes as an alternative for controlling fungal growth. The Petri plates containing Sabouraud dextrose agar with chloramphenicol (50 μg/mL) were exposed for collecting the fungi. The plates were incubated at 28 °C for seven days; then the colony forming unitscounting, and description were performed. The identification of fungi was performed by the morphological analysis of isolated colonies. The main group of fungi isolated throughout the industry was Cladosporium spp. Antifungal tests were performed by diffusion technique in solid medium with discs containing terpenes: carvacrol, citronellal, citral, linalool, thymol, terpinolene, p-cymene and β-caryophyllene. The effectiveness of some of these terpenes against Cladosporium spp. strains was shown, especially citral and carvacrol. Based on these results, the fruit pulp industry shows vulnerable ambient air, notably with high contamination by Cladosporium spp. Thus, it is aimed at promoting further studies with natural drugs in order to reduce the fungal contamination in food.