Cultivation of Candida sp. LEB-M3 in glycerol: lipid accumulation and prediction of biodiesel quality parameters.

The quality of biodiesel from lipids produced by the yeast Candida sp. LEB-M3 was predicted, by the use of mathematical models for parameters that specify quality as a function of the fatty acid profile. The lipid production was studied according to the experimental design methodology, for different cultivation conditions for agitation and aeration. Lipid compositions were affected by the cultivation conditions, and the agitation presented a positive effect for the formation of monounsaturated fatty acids and negative effect for saturated fatty acids. Aeration had a positive effect on the formation of polyunsaturated fatty acids. According to the predictions by the mathematical models, the cetane number varied from 61 to 67, the oxidative stability from 11 to 17h, the iodine index from 55 to 75gI2/100g, density from 852 to 868kg/m(3). All cultivation conditions led to lipid compositions, whose predicted bioparameter values indicate that biodiesel from this lipid source should present current standard quality.