CELF pretreatment of corn stover boosts ethanol titers and yields from high solids SSF with low enzyme loadings

摘要: A major challenge to economically produce ethanol from lignocellulosic biomass is achieve industrially relevant titers (>50 g L−1) control operating and capital costs for downstream operations while maintaining high yields. However, due reduced fermentation effectiveness at solids loadings, excessive amounts of enzymes are typically required obtain reasonable titers, thereby trading off with enzyme costs. In this study, we applied our newly developed Co-Solvent Enhanced Lignocellulosic Fractionation (CELF) pretreatment highly digestible glucan-rich corn stover. Simultaneous saccharification (SSF) was then pretreated CELF 15.5 wt% loadings (corresponding 11 glucan loadings) in modified shake flasks an titer 58.8 L−1 89.2% yield loading 15 mg-protein per g-glucan-in-raw-corn-stover (-RCS) only 5 days. By comparison, SSF stover dilute acid 18.3 (or 10 loading) achieved a 47.8 73.0%, respectively, despite needing longer times (∼20 days) additional 18 h prehydrolysis 50 °C. Remarkably, although were more economical 2 g-glucan-in-RCS, realized final consistently above yields over 80%.