Discovery of novel secondary metabolites from the basidiomycete Lentinus cf. sajor-caju and their inhibitory effects on Staphylococcus aureus biofilms

By Haoxuan Zeng, Marc Stadler, Cony Decock, Josphat Clement Matasyoh, Hedda Schrey and Mathias Müsken

Abstract: Three novel derivatives of microporenic acid, microporenic acids H–J, were identified from submerged cultures
of a Lentinus species obtained from a basidiome collected during a field trip in the tropical rainforest in Western
Kenya. Their structures were elucidated via HR-ESIMS spectra and 1D/2D NMR spectroscopic analyses, as well as
by comparison with known derivatives. Applying biofilm assays based on crystal violet staining and confocal
microscopy, two of these compounds, microporenic acids H and I, demonstrated the ability to inhibit biofilm
formation of the opportunistic pathogen Staphylococcus aureus. Thereby, they were effective in a concentration
range that did not affect planktonic growth. Additionally, microporenic acid I enhanced the anti-biofilm activity
of the antibiotics vancomycin and gentamicin when used in combination. This opens up possibilities for the use
of these compounds in combination therapy to prevent the formation of S. aureus biofilm