Enhanced camptothecin production by ethanol addition in the suspension culture of the endophyte, Fusarium solani

•Ethanol as carbon and energy source for the endophyte, Fusarium solani.•Ethanol as an elicitor to enhance camptothecin production by the endophyte F. solani.•Using extract of a non-camptothecin producing plant for camptothecin production.

Ethanolic extract of a non-camptothecin producing plant, Catharanthus roseus when added in the suspension culture of the endophyte Fusarium solani known to produce camptothecin, resulted in enhanced production of camptothecin by 10.6-fold in comparison to that in control (2.8 μg/L). Interestingly, addition of pure ethanol (up to 5% v/v) in the suspension culture of F. solani resulted in maximum enhancement in camptothecin production (up to 15.5-fold) from that obtained in control. In the presence of ethanol, a reduced glucose uptake (by ∼40%) and simultaneous ethanol consumption (up to 9.43 g/L) was observed during the cultivation period (14 days). Also, the total NAD level and the protein content in the biomass increased by 3.7- and 1.9-fold, respectively, in comparison to that in control. The study indicates a dual role of ethanol, presumably as an elicitor and also as a carbon/energy source, leading to enhanced biomass and camptothecin production.