Bioconversion of waste glycerol for enhanced lipid accumulation in Trichosporon shinodae

Oleaginous yeast lipids have myriad of industrial applications that are gaining significant interest owing to shorter incubation, ability to use broad spectrum substrates, and quality lipids. However, the lipid content produced is low and need to enhance by optimization of varied parameters. In the present study, crude glycerol a by-product of biodiesel industry was supplemented to Trichosporon shinodae for lipid accumulation using central composite design (CCD) of response surface methodology (RSM). The developed quadratic model was found to be significant with the R² value of 95.20% and adj. R² value of 91.97%. An optimal lipid content of 49.85 ± 0.8% (w/w) was obtained using T. shinodae with 6.2% (v/v) inoculum volume, pH 3.6, C/N ratio 105, 1.52 (g/L) of MgSO₄, and 4.55 mM FeSO₄ in 120.72 h at 30 °C. Lipid composition from T. shinodae depicted the presence of linoleic acid (C18:2), oleic acid (C18:1), stearic acid (C18:0), palmitic acid (C18:0), myristic acid (C14:0), and lauric acids (C12:0), respectively. T. shinodae lipids have 61.1% (w/w) saturated fatty acids and unsaturated fatty acids proportion accord to 38.9% (w/w). Lipid composition of T. shinodae indicates that these lipids were suitable for synthesis of high value products like fuel additives, surfactants, detergents, and cleaning applications.