Ethanol increases carotenoid production in Phaffia rhodozyma

Addition of ethanol (0.2%) to cultures of the yeast Phaffia rhodozyma increased the specific rate of carotenoid production [(carotenoid)(cell mass)(-1)(time)(-1)]. The incremental increase in carotenoid synthesis with ethanol was highest in carotenoid-hyperproducing strains. Ethanol increased carotenoid production when it was added at various points during the lag and active growth phases, Ethanol increased alcohol dehydrogenase and hydroxy-methyl-glutaryl-CoA (HMG-CoA) reductase activities, Our results indicate that increased carotenoid production by ethanol is associated with induction of HMG-CoA reductase and possibly activation of oxidative metabolism.