Inhibitor degradation by Rhodosporidium toruloides NRRL 1588 using undetoxified wood hydrolysate as a culture media

Abstract

Lignocellulosic biomass has been identified as a renewable and sustainable feedstock to produce liquid hydrolysates as a suitable substrate to produce a variety of compounds through biochemical processes. Nevertheless, the main challenge to using this substrate is the hydrolysis needed to release fermentable sugars. This pretreatment leads to the production of microbial toxic compounds such as furans, phenols and organic acids. In this work, an oleaginous yeast, R. toruloides NRRL 1588, was used to study its ability to degrade inhibitors in C5 and C6 wood hydrolysates obtained from forestry residues. The study showed that R. toruloides NRRL 1588 can grow, accumulate lipids, and degrade up to 8.01 mgL−1 h−1 of furfural, 5.63 mgL−1 h−1 of 5-hydroxy methyl furfural, 1.70 mgL−1 h−1 of levulinic acid, 1.15 mgL−1 h−1 of syringaldehyde, 0.67 mgL−1 h−1 of vanillin, and 1.03 mgL−1 h−1 of vanillic acid. This work confirms the robustness of R. toruloides NRRL 1588 when grows in wood hydrolysates containing inhibitory compounds.