Comparative fermentability of a glucose/xylose enriched enzymatic slurry using different yeast strains
摘要
Lignocellulosic biomass represents a sustainable energy source as ethanol fuel demand increases; process integration and efficient C6/C5 sugars utilization are essential for achieving techno-economically viable production. Here, alkaline-sulfite pretreatment combined with disc refining was applied to sugarcane bagasse for conserving most of cellulose and hemicellulose fractions. Then, β-glucosidase supplementation of cellulase at rational enzyme dosage (18 FPU/g biomass) was established for the enzymatic hydrolysis of the pretreated solids, achieving approximately 75% conversion yield for both cellulose and xylan. The resulting enzymatic slurry was directly fermented without solid-liquid separation and used to evaluate the effects of temperature and nutrient supplementation on ethanol fermentation by three yeast strains. Under optimal conditions (30 °C with nutrients), Kluyveromyces marxianus Y-6860 exhibited higher ethanol productivity (