STUDY OF GROWTH-PARAMETERS FOR PHAFFIA-RHODOZYMA CULTIVATED IN PEAT HYDROLYSATES

The yeast Phaffia rhodozyma, known for its ability to synthesize carot enoids, was adapted and cultivated in liquid-phase media using peat hy drolysates as the main substrate source. The hydrolysates were prepare d using high-pressure treatment at 185-degrees-C, without the addition of acid. The growth of the yeast was studied as a function of the pH, temperature, culture time, and agitation speed. The best conditions f or the growth of the yeast were: a pH of 7, a temperature of 18-degree s-C, 5-d culture time, and 200-rpm agitation. Under those conditions, P. rhodozyma produced a concentration of 1279.82 mug carotenoids g-1 d ry yeast, which compares well with other previously reported results.