Efficient production 2,3-butanediol from biomass-derived sugars by Raoultella ornithinolytica TH-21, a newly isolated lignocellulose-degrading bacterium

Abstract

Efficient bioconversion of lignocellulose to valuable products can be performed by bacteria that are both capable of degrading biomass and producing platform chemicals. This study reported a newly isolated lignocellulolytic strain, Raoultella ornithinolytica TH-21 showing great potential as an ideal biocatalyst for producing 2,3-butanediol (2,3-BDO). Strain TH-21 exhibited the capability of assimilation of multiple carbon sources for 2,3-BDO production. It could directly convert 50 g/L of xylose, mannitol, cellobiose and xylan into 2,3-BDO with the maximum production of 20.04 g/L, 16.56 g/L, 20.06 g/L and 11.25 g/L, respectively. In addition, the lignin, cellulose, and hemicellulose present in sugarcane bagasse were degraded by strain TH-21 with a rate of 26.96%, 24.6%, and 33% after 7 days of treatment, respectively. Furthermore, FTIR, XRD and SEM analysis revealed that strain TH-21 can effectively depolymerize the lignin and holocellulose in sugarcane bagasse through its efficient secretion of lignocellulolytic enzymes. Thus, these findings indicated that strain TH-21 might be a promising biocatalyst for the effective bioconversion of lignocellulose to high-value chemicals.