Biorefinery-centric ethanol and oleochemical production employing Yarrowia lipolytica and Pichia farinosa.

[Display omitted] • Food waste and effluent yield valuable oleochemicals and alcohol synthesis. • YL exhibits highest lipid production in synthetic carbon systems. • FAD2 and ADH expression are high in synthetic carbon than waste carbon source. • Both YL and PF produced high protein content during growth phase. • A biorefinery framework was established to synthesize the chemicals from food-waste. The research examined the capabilities of Yarrowia lipolytica (YL) and Pichia farinosa (PF) in converting sugars to ethanol and oleochemicals. Lipid, ethanol, protein yield and gene-expressions were analysed at different substrate concentrations (3 to 30 g/L) with glucose, food waste, and fermentation-effluent. Optimal results were obtained at 20 g/L using both synthetic carbon with 4.6 % of total lipid yield. Lauric and Caprylic acid dominance was noted in total lipid fractions. Protein accumulation (6 g/L) was observed in glucose system (20 g/L) indicating yeast strains potential as single-cell proteins (SCP). Fatty-acid desaturase (FAD12) and alcohol dehydrogenase (ADH) expressions were higher at optimum condition of YL (1.15 × 10−1, 3.8 × 10−2) and PF (5.8 × 10−2, 3.8 × 10−2) respectively. Maximum carbon reduction of 87 % depicted at best condition, aligning with metabolic yield. These findings highlights promising role of yeast as biorefinery biocatalyst. [ABSTRACT FROM AUTHOR]