METHODOLOGY.The effect of precursors on the anticancer alkaloid production by submerged fermentation using M. anisopliae 3935 was studied, according to complete experimental design 2 2 with three central points.The results showed that lysine was the most important variable, however, when both lysine and glucose were added to the fermentation medium, the alkaloid production reached, approximately, 17 mg L -1 after 120 hours of fermentation.Then, the scale-up of the process was carried out and these results were confirmed.Finally, 35 mg L -1 of alkaloid at 192 h were attained after increment of added aminoacid lysine.