Combined effect of phosphorus, magnesium, yeast extract on lipid productivity of Yarrowia lipolytica grown with molasses

Inadequate global fossil fuel reserves have forced researchers to investigate alternative fuel sources, and oleaginous microorganisms have attracted attention with their potential. Since high lipid production yield is an important criterion for suitable fuel production, in this study an oleaginous yeast, Yarrowia lipolytica, was selected and the lipid and biomass productivity under molasses (M20) substrate and nutrient supplementation was investigated. The effect of phosphorus as dipotassium hydrogen phosphate (K₂HPO₄), magnesium as magnesium sulphate (MgSO₄), and yeast extract supplementation to molasses (M20) were evaluated individually and in combination. In addition, two quadratic models, using Box-Wilson central composite design, were used to correlate the phosphorus, magnesium and yeast extract concentrations that would achieve the highest biomass and lipid productivity. The study has shown that molasses (M20) supplemented with 336 mg/L K₂HPO₄, 0.17 g/L MgSO₄ and 4.54 g/L yeast extract had the highest biomass productivity (80.7 mg/L/hour) and the highest lipid productivity (28.3 mg/L/hour). These productivity results were 1.44-fold and 2.42-fold higher than those of yeast extract-peptone-dextrose (YPD) broth, respectively. With enhanced biomass and lipid productivity, Yarrowia lipolytica can thus be used effectively in the fermentation industry.