Kinetic and Stoichiometric Parameters in the Production of Carotenoids by Sporidiobolus salmonicolor (CBS 2636) in Synthetic and Agroindustrial Media

Abstract

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 25 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 microg/L) and agroindustrial (502 microg/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 microg/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 (micro (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 microg 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.

Comparative Studies of β-carotene and Protein Production FromDunaliella salinaIsolated From Lake Hoze-soltan, Iran

“…The carotenoids/chlorophyll production rate and protein/chlorophyll production rate were calculated by Equation 3 (Valduga et al, 2009):…”

INTERFERÊNCIA DO pH INICIAL E VOLUME DE MEIO NA PRODUÇÃO DE CAROTENOIDES POR Sporidiobolus pararoseus

“…O pH do meio sintético apresentou pouca variação (de 4 para 3,7) enquanto que o meio agroindustrial apresentou uma elevação considerável de 4 para 8,5, comportamento semelhante ao observado no presente trabalho. Os autores relacionam essas alterações de pH a uma possível proteólise das células, um fenômeno natural devido a escassez de substrato e consequente degradação dos aminoácidos, o que leva a liberação de compostos amoníacos que elevam o pH a faixas alcalinas, principalmente quando o microorganismo não possui capacidade de assimilar outra fonte de carbono (VALDUGA, et al 2009 …”

Technological Aspects of β-Carotene Production

“…On the other hand, Sporidiobolus salmonicolor, when growing in synthetic and agroindustrial-based media produced larger amounts of carotenoids (176 and 163 μg g −1 of total carotenoids, respectively), being 32% correspondent to β-carotene. This result was improved to 253 μg g −1 of total carotenoids, just altering the ratio in solvent extraction with acetone and methanol from 1/1 to 7/3, in presence of DMSO and a liquid nitrogen source (Valduga et al 2009c(Valduga et al , 2009b. In another work, Valduga and colleagues (2009d), using 40 g L −1 glucose, 10 g L −1 malt extract, and 14 g L −1 peptone at 180 rpm, 25°C and initial pH 4.0, had achieved a maximum concentration of 287.7 μg g −1 of total carotenoids.…”