FERMENTATION PROCESS

A method for producing lovastatin by a microorganism in a fermentation process having a seed culture stage and a main fermentation stage, includinga) cultivating a microorganism biomass in the seed culture stage to produce an inoculum;b) transferring the inoculum into a fermentation medium in the main fermentation stage; and,c) maintaining steady stage conditions in the main fermentation stage, thereby producing a fermentation broth containing lovastatin. Preferably, the steady state conditions are maintained in the main fermentation stage by one or more of feeding of organic carbon sources; controlling glucose and/or total reducing sugar content; feeding of organic and/or inorganic nitrogen sources; controlling pH; controlling foam level; controlling the mass of the fermentation broth by withdrawals and feedings; and, controlling the dissolved oxygen level.