Screening Of Natural Compounds To Inhibit Growth And Mycotoxin Production By Aspergillus Spp. And Penicillium Spp.

Fungi are important spoilage agents of several foods causing great economic losses worldwide. Moreover, some moulds can produce toxic metabolites that may be mutagenic and therefore constitute a public health concern, whereas the growth of spoilage fungi results in organoleptic and chemical changes leading to the consumer rejection. Spoilage fungi are commonly controlled by synthetic chemicals; however, consumers demand for food without preservatives and associate healthy and safe foods with free or minimally processed products. As a consequence, attention has been increasingly focused on exploiting alternative methods to protect feed and food from fungal contamination such as natural antifungal molecules or biological control. The aim of this work was to evaluate the ability of some natural compounds belonging to different chemical families to affect the growth and spore germination as well as mycotoxin production of Aspergillus spp. and Penicillium spp.. Thirty compounds including furanones, oxylipins, unsaturated and saturated fatty acids, aldehydes and essential oils were screened on desiccated coconut agar at different concentrations, in the presence or absence of light and at different incubation temperatures. Moreover, mycotoxin production was confirmed and quantified by HPLC-fluorimeter detection analysis. The results evidenced that most of the substances were more active when moulds were grown in the absence of light. In particular, hexanal, bisabolol and alfa-angelica lactone induced both a delay in spore germination and a reduction of mycotoxin production in such conditions. On the contrary, 5-ethyl-3-hydroxy-4-methyl-2(5H)-furanone was found to be the most effective molecule controlling aflatoxinogenic strains in all the experimental conditions taken into consideration