Limiting ergosterol accumulation through metabolic control increased lycopene production by Blakeslea trispora. Lycopene and ergosterol are both biosynthesized from a common precursor, farnesyl diphosphate (FPP). The effects of two ergosterol biosynthesis inhibitors, terbinaline hydrochloride (TH) and ketoconazole, on the production of lycopene by B. trispora were investigated. TH at 0.7 mg/l and ketoconazole at 30 mg/l added to the medium at 48 h of fermentation caused an increase in lycopene content of 23% or 277%, respectively. The timing of addition for both inhibitors at 48 h resulted in the most optimal lycopene productivity, however, compared with TH, ketoconazole was superior in enhancing lycopene production by inhibiting ergosterol biosynthesis. (C) 2007 Published by Elsevier Ltd.