Conversion of waste materials into very long chain fatty acids by the recombinant yeast Yarrowia lipolytica.

Abstract

Erucic acid (C22:1Δ13) has several industrial applications including its use as a lubricant, surfactant and biodiesel and composite material constituent. It is produced by plants belonging to the Brassicaceae family, especially by the high erucic acid rapeseed. The ability to convert oleic acid into erucic acid is facilitated by FAE1. In this study, FAD2 (encoding Δ12-desaturase) was deleted in the strain Po1d to increase oleic acid content. Subsequently, FAE1 from Thlaspi arvense was overexpressed in Yarrowia lipolytica with the Δfad2 genotype. This resulted in the YL10 strain producing very long chain fatty acids, especially erucic acid. The YL10 strain was cultivated in media containing crude glycerol and waste cooking oil as carbon substrates. The cells grown using glycerol produced microbial oil devoid of linoleic acid, which was enriched with very long chain fatty acids, mainly erucic acid (9% of the total fatty acids). When cells were grown using waste cooking oil, the highest yield of erucic acid was obtained (887mg L-1). However, external linoleic and α-linolenic were accumulated in cellular lipids when yeasts were grown in an oil medium. This study describes the possibility of conversion of waste material into erucic acid by a recombinant yeast strain.