Evaluation of antioxidant, antimicrobial and tyrosinase inhibitory activities of extracts from <em>Tricholosporum goniospermum</em>, an edible wild mushroom

Abstract

Tricholosporum goniospermum is an excellent edible mushroom whose compounds and biological properties are still unknown. In this study, n-hexane, ethyl acetate and methanol extracts from fruiting bodies and liquid-cultured mycelia were compared for the analysis of phenolic compounds, the evaluation of scavenger and reducing activities, and the enzyme inhibition of α-amylase, acetylcholinesterase, butyrylcholinesterase and tyrosinase. Additionally, T. goniospermum extracts were evaluated for antibacterial and antimycotic activities against Gram+ and Gram− bacteria, and clinical yeast and fungal dermatophytes. Finally, based on the extract content in phenolic compounds, in silico studies, including the docking approach, were conducted to predict the putative targets (namely tyrosinase, lanosterol-14-α-demethylase, the multidrug efflux system transporters of E. coli (mdtK) and P. aeruginosa (pmpM), and S. aureus β-lactamase (ORF259)) underlying the observed bio-pharmacological and microbiological effects. The mycelia methanolic extract was the richest in gallic acid, whereas fruit ethyl acetate extract was the sole to show levels of catechin. Specifically, docking runs demonstrated an affinity of catechin towards all docked proteins, in the micromolar range. These in silico data are consistent, at least in part, with the highest activity of ethyl acetate extract as an antimicrobial and anti-tyrosinase agent. The ethyl acetate extracts were also noted as being the most active on α-amylase. Concluding, among tested extracts, the ethyl acetate extract showed the highest efficacy as both antimicrobial and anti-tyrosinase agent, thus suggesting innovative pharmacological applications of T. goniospermum.