From crude glycerol to carotenoids by using a Rhodotorula glutinis mutant

"In this work eighteen red yeasts were screened. for carotenoids production on glycerol containing medium.. Strain C2.5t1 of Rhodotorula glutinis, that showed the. highest productivity, was UV mutagenized. Mutant 400A15,. that exhibited a 280 % increase in b–carotene production in. respect to the parental strain, was selected. A central composite. design was applied to 400A15 to optimize carotenoids. and biomass productions. Regression analyses of the quadratic. polynomial equations obtained (R2 = 0.87 and 0.94,. for carotenoids and biomass, respectively) suggest that the. models are reliable and significant (P\\0.0001) in the. prediction of carotenoids and biomass productions on the. basis of the concentrations of crude glycerol, yeast extract. and peptone. Accordingly, total carotenoids production. achieved (14.07 ± 1.45 mg l-1) under optimized growth. conditions was not statistically different from the maximal. predicted (14.64 ± 1.57 mg l-1) (P\\0.05), and it was. about 100 % higher than that obtained under un-optimized. conditions. Therefore mutant 400A15 may represent a biocatalyst. of choice for the bioconversion of crude glycerol. into value-added metabolites, and a tool for the valorization. of this by-product of the biodiesel industry."