Yenepoya Research Centre, Yenepoya University, Mangalore 575018, India.
Carbohydr Polym. 2012 Oct 1;90(2):1038-45. doi: 10.1016/j.carbpol.2012.06.040. Epub 2012 Jun 28.
Pretreatment of lignocellulosic biomass has been taken up as a global challenge as it comprises a large renewable source of fermentable sugars. In this study, effect of electron beam irradiation (EBI) on a hybrid grass variety investigated as a biomass pretreatment method. Dry biomass samples after characterization were exposed to EBI doses of 0, 75, 150 and 250 kGy. The pretreated biomass samples were enzymatically hydrolyzed using Trichoderma reesei ATCC 26921 cellulase for 144 h. The enzyme loadings were 15 and 30 FPU/g of biomass. The structural changes and degree of crystallinity of the pretreated biomass were studied by FTIR, XRD and SEM analyses. The lignocellulosic biomass sample showed 12.0% extractives, 36.9% cellulose, 28.4% hemicellulose, 11.9% lignin and 8.6% ash. Significant improvements in the reducing sugar and glucose yields were observed in the hydrolysate of EBI pretreated biomass compared to the control. In 250 kGy exposed samples 79% of the final reducing sugar yield was released within 48 h of hydrolysis at an enzyme loading rate of 30FPU/g of biomass. The IR crystallinity index calculated from the FTIR data and degree of crystallinity (XRD) decreased in the EBI treated samples. A significant negative correlation was observed between degree of crystallinity and the glucose yield from enzymatic hydrolysis.
预处理木质纤维素生物质已被视为一项全球性挑战，因为它是一种可再生的可发酵糖的重要来源。在这项研究中，采用电子束辐照（EBI）对一种杂交草品种进行了处理，将其作为一种生物质预处理方法进行了研究。经过特性分析后的干燥生物质样品分别在 0、75、150 和 250 kGy 的 EBI 剂量下进行辐照处理。预处理后的生物质样品用里氏木霉 ATCC 26921 纤维素酶进行 144 小时的酶解。酶的用量为 15 和 30 FPU/g 的生物质。通过 FTIR、XRD 和 SEM 分析研究了预处理生物质的结构变化和结晶度。木质纤维素生物质样品的抽提物含量为 12.0%，纤维素含量为 36.9%，半纤维素含量为 28.4%，木质素含量为 11.9%，灰分含量为 8.6%。与对照相比，EBI 预处理生物质的水解液中还原糖和葡萄糖产率均有显著提高。在 250 kGy 暴露样品中，在 30FPU/g 的生物质酶用量下，水解 48 小时内，最终还原糖产率中有 79%被释放。从 FTIR 数据计算得出的 IR 结晶度指数和 XRD 结晶度均降低。酶解葡萄糖产率与结晶度之间呈显著负相关。
