Composition and antimicrobial activity of hydroalcoholic extracts of Pleurotus eryngii var. ferulae and P. eryngii var. elaeoselini

The basidiomycetes Pleurotus eryngii var. ferulae Lanzi and P. eryngii var. elaeoselini Venturella et al., belong to the P. eryngii species complex, acting as facultative biotrophs in association with Ferula communis L. and Elaeoselinum asclepium L. (Apiaceae), respectively. Together with other species of Pleurotus, the consumption of these fungi has rapidly increased in recent decades, not only thanks to their nutritional properties and pleasant flavour, but also for their bioactive and medicinal properties. Recent studies on P. eryngii var. elaeoselini and P. eryngii var. ferulae, showed that they exhibited important medicinal properties such as antioxidant activity and in vitro antitumor effect on human colon cancer cell lines (HCT116), respectively [1-2]. A qualitative study to clarify the chemical composition of the hydroalcoholic extracts of these two mushrooms was carried out by liquid chromatography-mass spectrometry (LC-MS). The analyses carried out allowed the identification of some secondary metabolites belonging to different chemical classes. In fact, phenolic compounds, triterpenes and triterpenoids, medium-chain fatty acids and long-chain fatty acids, polysaccharide and monosaccharide compounds have been found, as well as the presence of proteins, peptides and lectins. The highlighted composition agrees with previous literature data regarding the chemical composition of these fungal extracts [3-5]. Their potential antimicrobial activity against some phytopathogenic microorganisms was then evaluated. The antibacterial activity was assessed against Xanthomonas campestris and Pseudomonas viridiflava, responsible for numerous pathologies affecting food crops of great interest (kiwi, tomato, melon, aubergine, pepper, rice, lemon, broccoli, cabbage), characterized by leaf spots, rotting and rust. The antifungal activity was evaluated against the phytopathogens Botrytis cinerea, Cadophora spp., Monilinia laxa and M. frutticola, for the appearance of mold and rot on numerous food plant species (vine, apricot, peach, almond, cherry). The results obtained can be useful for expanding the knowledge on the possible use of these fungal species in the agricultural sector.