Engleromophilane, a new broad spectrum bioactive eremophilane-type sesquiterpene from Engleromyces sinensis fungus

Abstract

A new eremophilane sesquiterpene, named engleromophilane (1) together with known eremoxylarin E (2) and steroids (3-7) were isolated from the fungus Engleromyces sinensis culture. The structures were deduced by the analysis of spectroscopic and MS data, together with the comparison of calculated 13C NMR chemical shifts and Electronic Circular Dichroism (ECD) spectra. Compound 1 showed cytotoxic effects against Hela, PC-3, HT29 and A549 cell lines with IC50 in the ranges of 4.84–9.48 μg/mL. Compounds 1 and 2 exhibited substantial antimicrobial activity against E. coli, S. aureus, and B. subtilis. Moreover, compounds 1–3 showed α-glucosidase inhibitory activity, in which 2 displayed a strong inhibitory effect with an IC50 value of 0.13 ± 0.01 µg/mL. This work has given additional value to the E. sinensis fungus as a remarkable bioactive compound producer, together with the possibility of increasing cultivation to industrial scales.