Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing 100083, China.
Department of Bioproducts and Biosystems Engineering, University of Minnesota, St. Paul, MN 55108, USA.
Bioresour Technol. 2019 Feb;273:231-236. doi: 10.1016/j.biortech.2018.11.024. Epub 2018 Nov 9.
A cost efficient synergistic strategy combining mild alkaline pretreatment (0.5-5% NaOH at 70 °C for 60 min) and bovine serum albumin (BSA) blocking of lignin was evaluated for effective conversion of poplar. The highest glucose yield of 69.2% was obtained for 5% alkaline pretreated sample, which was 4.4 times that of untreated sample. The enhanced enzymatic hydrolysis was attributed to significant hemicelluloses removal with limited delignification. Delignification mainly occurred in secondary wall, leading to more open cell wall structure, thus facilitating better transport of enzyme. Hemicelluloses removal helped split adjacent microfibrils, thus increased the specific sites for cellulase binding. After BSA addition in enzymatic hydrolysis, cellulose conversion further improved to 78.4% with 33% reduction of cellulase dosage due to decreased non-specific adsorption of cellulase on residual lignin. The utilization of synergistic alkaline pretreatment - BSA strategy may improve the overall economics of biomass conversion and successful commercial implementation of biorefineries.
评价了一种结合温和堿预处理（70℃下 0.5-5%NaOH 处理 60min）和牛血清白蛋白（BSA）封闭木质素的具有成本效益的协同策略，以实现杨树的有效转化。5%堿预处理样品的葡萄糖得率最高，达到 69.2%，是未处理样品的 4.4 倍。增强的酶水解归因于半纤维素的显著去除和有限的木质素脱除。木质素的脱除主要发生在次生壁，导致细胞壁结构更加开放，从而有利于酶的更好传输。半纤维素的去除有助于分裂相邻的微纤维，从而增加了纤维素酶结合的特定部位。在酶水解中添加 BSA 后，由于纤维素酶在残余木质素上的非特异性吸附减少，纤维素转化率进一步提高到 78.4%，纤维素酶用量减少了 33%。协同堿预处理-BSA 策略的利用可能会提高生物质转化的整体经济性，并成功实现生物精炼厂的商业化。
