[Effect of carbon source and cultivation temperature on growth limitation of Candida tropicalis by biotin]

The effect of biotin on the specific growth rate of Candida tropicalis was studied on media with various sources of carbon nutrition at temperatures of 29 and 39degreesC. The yeast was found to require 3--5 times less biotin on the medium with paraffin than on the medium with glucose and hexodecane, and 3--4 times more biotin on the same substrate with an increase in temperature. The growth rate increased by 36--40% on liquid paraffins containing 0.5 mcg/litre of biotin at 29degreesC and 1.5--2.0 mcg/litre of biotin at 39degreesC. The saturation constant of biotin increased from 0.033 to 0.063 mcg/litre on the medium with paraffin, and more by an order on the medium with glucose and hexadecane, at a rise of growth temperature from 29 to 39degreesC.