Applied Biochemistry and Biotechnology, Vol.157, No.1, 61-69, 2009
Kinetic and Stoichiometric Parameters in the Production of Carotenoids by Sporidiobolus salmonicolor (CBS 2636) in Synthetic and Agroindustrial Media
With the objective of determining the kinetic behavior (growth, substrate, pH, and carotenoid production) and obtain the stoichiometric parameters of the fermentative process by Sporidiobolus salmonicolor in synthetic and agroindustrial media, fermentations were carried out in shaken flasks at 25A degrees C, 180 rpm, and initial pH of 4.0 for 120 h in the dark, sampling every 6 h. The maximum concentrations of total carotenoids in synthetic (913 mu g/L) and agroindustrial (502 mu g/L) media were attained approximately 100 h after the start of the fermentative process. Carotenoid bioproduction is associated with cell growth and the ratio between carotenoid production and cell growth (Y (P/X)) is 176 and 163 mu g/g in the synthetic and agroindustrial media, respectively. The pH of the agroindustrial fermentation medium varied from 4.2 to 8.5 during the fermentation. The specific growth rate (mu (X)) for S. salmonicolor in synthetic and agroindustrial media was 0.07 and 0.04 h(-1), respectively. The synthetic medium allowed for greater productivity, obtaining maximum cell productivity (P (x)) of 0.08 g L-1 h(-1) and maximum total carotenoid productivity (P (car)) of 14.2 mu g L-1 h(-1). Knowledge of the kinetics of a fermentative process is of extreme importance when transposing a laboratory experiment to an industrial scale, as well as making a quantitative comparison between different culture conditions.
Keywords:Sporidiobolus salmonicolor;Synthetic media;Agroindustrial media;Carotenoids;Kinetic parameters;Stoichiometric parameters