Production of oligosaccharides and biofuels from Miscanthus using combinatorial steam explosion and ionic liquid pretreatment

Pretreatment strategies are fundamental to effectively deconstruct lignocellulosic biomass and economically produce biofuels, biomaterials and bio-based chemicals. This study evaluated individual and combinatorial steam explosion (SE) and ionic liquid (IL) pretreatments for production of high-value oligosaccharides from a novel seed-based Miscanthus hybrid (Mx2779). The two ILs used for pretreatment were triethylammonium hydrogen sulphate [TEA][HSO4] and 1-ethyl-3-methylimidazolium acetate [C(2)mim][OAc]. The results showed that each pretreatment leads to distinct effects on the fragmentation (cellulose and xylan dissolution, delignification, deacetylation) and physicochemical modification (cellulose and lignin properties) of lignocellulose. This, in turn, dictated enzymatic hydrolysis efficiencies of the cellulose pulp to glucose or gluco-oligosaccharides for downstream applications. Our findings suggest that the stand-alone SE or [C(2)mim][OAc] pretreatments may offer cost advantages over [TEA][HSO4] through the production of oligosaccharides such as xyloand glucooligosaccharides. This study also highlights technical and economic pretreatment process challenges related to the production of oligosaccharides from Miscanthus Mx2779 biomass.

Automated summary

Pretreatment strategies are crucial for deconstructing lignocellulosic biomass for the production of biofuels, biomaterials, and bio-based chemicals. This study evaluated the effects of steam explosion and ionic liquid pretreatments on the production of high-value oligosaccharides from Miscanthus Mx2779 biomass. The results showed distinct impacts on lignocellulose fragmentation and physicochemical modifications, influencing enzymatic hydrolysis efficiencies.