Determination of kinetic parameters of growth and carotenogenesis in the red yeast Xanthophyllomyces dendrorhous

Abstract

Glucose-limited continuous culture experiments with Xanthophyllomyces dendrorhous ATCC 24202 were carried out in a 2.5 L jar fermentor at 20°C and pH 4.5. A reciprocal plot of the steady-state data at a dilution rate of 0.037∼0.096 h−1 was used to estimate a maximum specific growth rate constant of 0.11 h−1 and a Monod constant of 260 mg/L. The degree of carotenogenesis in X. dendrorhous was also investigated in terms of the residence time, which is the reciprocal of the dilution rate. The carotenoid content related to the residence time appeared to assume a typical form of saturation kinetics. The maximum carotenoid content for the strain was estimated to be 0.6 μg/mg dry cell weight. The saturation constant, which was tentatively defined in this work, was found to be 7.2 h.