Production of long-chain hydroxy fatty acids by Starmerella bombicola

Abstract

To decrease our dependency for the diminishing source of fossils resources, bio-based alternatives are being explored for the synthesis of commodity and high-value molecules. One example in this ecological initiative is the microbial production of the biosurfactant sophorolipids by the yeast Starmerella bombicola. Sophorolipids are surface-active molecules mainly used as household and laundry detergents. Because S. bombicola is able to produce high titers of sophorolipids, the yeast is also used to increase the portfolio of lipophilic compounds through strain engineering. Here, the one-step microbial production of hydroxy fatty acids by S. bombicola was accomplished by the selective blockage of three catabolic pathways through metabolic engineering. Successful production of 17.39 g/l (ω-1) linked hydroxy fatty acids was obtained by the successive blockage of the sophorolipid biosynthesis, the β-oxidation and the ω-oxidation pathways. Minor contamination of dicarboxylic acids and fatty aldehydes were successfully removed using flash chromatography. This way, S. bombicola was further expanded into a flexible production platform of economical relevant compounds in the chemical, food and cosmetic industries.

Production of new antimicrobial palm oil-derived sophorolipids by the yeast Starmerella riodocensis sp. nov. against Candida albicans hyphal and biofilm formation

“…The underlying genes and enzymes associated with SLs production in S. bombicola are recently documented [ 37 ]. Alternatively, shake-flask and bioreactor experiments have been reported as common cultivation and scale-up method to produce higher amounts of SLs biosurfactant [ 8 , 23 , 44 , 56 , 58 – 60 ].…”

Exploring the transportome of the biosurfactant producing yeast Starmerella bombicola

“…Furthermore, they are involved in the transport of hydrophobic molecules [ 20 ]. Which means that these transporters are also likely candidates to explain why S. bombicola is exceptionally good at export of fatty acids and derivatives thereof [ 14 , 21 ].…”

Comprehensive metabolomics reveals correlation between sophorolipid biosynthesis and autophagy

“…SL quantification standard curves were constructed with inhouse standards of bola and acidic SLs (> 98.8% pure), which were previously identified by 1 H NMR analysis as described in [15] and by 1 H and 13 C NMR as described in [8]. Ultra-high performance liquid chromatography coupled to hybrid quadrupole-orbitrap high-resolution mass spectrometry (UHPLC-HRMS) was used in the negative ionisation mode for glycolipid identification (e. g. triglucolipids) as described in [16]. SL productivity and glucose consumption rates during retentostat incubation were calculated according to equations 1 and 2.…”