Laccase Pretreatment Enhancing Cellulose Extraction from Corn Straw with Deep Eutectic Solvent

The aim of this study was to examine the effect of laccase pretreatment on the cellulose extraction of corn straw with deep eutectic solvent (DES). All pretreatments significantly differed in separation of hemicellulose and lignin, and further in extraction efficiency of cellulose. The overall performance of laccase/xylanase system (LXS) exhibited the highest level between various pretreatment processes, whereas the lowest had the absence of mediator to the pretreatment. The highest differences were observed in the extraction efficiency of cellulose. The viscosity-average molecular weight (M-v) of the obtained cellulose varied from 22678.5 of the control sample to 24871.6 of the LXS sample and the cellulose yield from 42.9% to 99.2%, in which the temperature required in DES-based extraction was only 90 degrees C, far lower than that commonly used in DES-based extraction of straws. The mechanism of pretreatment effect was explained according to the composition and texturality together with lignin substructures.