Inducing secondary metabolite production by the endophytic fungus Chaetomium sp.through fungal-bacterial co-culture and epigenetic modification

The mixed fermentation of the fungal endophyte Chaetomium sp. with an autoclaved culture of the bacterium Pseudomonas aeruginosa on solid rice medium led to an up to 33-fold increase in the accumulation of constitutively present fungal secondary metabolites (3-10), which included four new butenolide derivatives (3-5 and 7). In addition, two further shikimic acid analogues (1 and 2) were obtained from mixed cultures that were neither detected in axenic cultures of the fungus nor of the bacterium. Chaetoisochorismin (1) possesses [a]

Ten new sesquiterpenoid derivatives, rhinomilisins A−J (1−10), along with six known analogues (11−16), were isolated from the mangrove-derived endophytic fungus Rhinocladiella similis. The structures of the new compounds were elucidated by their NMR and MS data, while the absolute configuration of 3 and 6 was determined by X-ray crystallographic analysis and Mosher's method, respectively. All isolated compounds (1−16) were evaluated for their cytotoxicity against the mouse lymphoma cell line L5178Y, and compounds 1, 7, and 15 showed moderate activity with IC 50 values of 5.0, 8.7, and 24.4 μM, respectively.