Production of new‐to‐nature sophorolipids by cultivating the yeast Candida bombicola on unconventional hydrophobic substrates

Abstract

The naturally occurring sophorolipids synthesized by Candida bombicola possess--despite their overall heterogeneity--little variation in the length of the lipid tail. The range is limited to C16-C18 fatty acids and is governed by the specificity of a cytochrome P450 monooxygenase. However, incorporation of fatty acids differing from the conventional C16-C18 range could broaden up the application potential of sophorolipids. The incorporation of medium-chain fatty acids should render the molecules more hydrophilic and consequently improve their water solubility. Two strategies to circumvent this C16-C18 preference are described in this paper. The first one skips the controlling action of the cytochrome P450 enzyme by supplying the yeast with already hydroxylated substrates, while the other method is based on the deception of the enzyme by presenting it substrates structurally resembling stearic acid. This later strategy can be applied to create very specific tailor-made sophorolipids when combined with post-fermentive modification.

White Biotechnology in Biosurfactants

“…Van Bogaert et al 53 proposed two strategies to overcome the challenges in producing sophorolipids having fatty acids with chain length of any choice. Cytochrome P450 monooxygenase, which catalyze the hydroxylation of fatty acid during sophorolipids biosynthesis, are very specific to fatty acid chain length and result in the incorporation of only long-chain fatty acid in sophorolipids structure.…”

Castor Oil as Secondary Carbon Source for Production of Sophorolipids Using <i>Starmerella bombicola</i> NRRL Y-17069

“…Presence of ricinoleic acid, hydroxyl fatty acid, makes castor oil different and unique than any other vegetable oil for SLs production. There are two pathways for sophorolipid biosynthesis first is hydroxylation of fatty acid generally C 16 -C 18 by cytochrome P450 monooxygenase and second is direct incorporation of hydroxylated molecule such as alcohol, diol reported by 11 . Castor oil form sophorolipids using both pathways as it contains ricinoleic acid which has hydroxyl functional group at 12 th position also have C 18 carbon chain with free ω and ω-1 position.…”

Towards a carbon-negative sustainable bio-based economy

“…Emerging fields, such as metabolic engineering, protein engineering, and synthetic biology, consolidate this transition and the specific microorganisms used in fermentation reactions are increasingly engineered to efficiently produce the desired compound. These “designer bugs” can be considered as real cell factories that are used to produce complex metabolites or their direct precursors with a myriad of applications in, among others, antibiotics (cephalexin), pharmaceuticals (artemisinin, taxol, resveratrol, and palifosfamide), food additives (vanillin, valencene, succinic acid, citric acid, and amino acids), cosmetics (farnesene), surfactants (rhamnolipids and sophorolipids), and chemicals ( D -lactic acid and isobutanol) (Park et al, 2007; Lee et al, 2009; Tsuruta et al, 2009; Ajikumar et al, 2010; Papini et al, 2010; Adsul et al, 2011; Van Bogaert et al, 2011). …”