Zhao Raoping, Sheng Yu, Yang Haiyan, Shi Zhengjun, Wang Dawei, Yang Jing
Key Laboratory for Yunnan Province Universities on Chemical Utilization of Forestry Lignocellulosic Biomass, Education of Department of Yunnan Province, Kunming 650224, China.
Key Laboratory for Yunnan Province Universities on Chemical Utilization of Forestry Lignocellulosic Biomass, Education of Department of Yunnan Province, Kunming 650224, China; School of Materials and Chemical Engineering, Southwest Forestry University, Kunming 650224, China.
Int J Biol Macromol. 2025 May;308(Pt 2):142361. doi: 10.1016/j.ijbiomac.2025.142361. Epub 2025 Mar 24.
Six different ternary deep eutectic solvent (DES) of tetraethylammonium chloride (TEAC)/oxalic acid (OA)-polyols were synthesized to improve the production of fermentable sugars and lignin by-products. The bamboo fractionation and bioconversion of cellulose residues can be enhanced by the ternary DES pretreatment, and its increasing efficiency was positively related to the alkyl carbon chain length and hydroxyl number of polyols in the hydrogen bond donor. The 1,4-butanediol (BDO)-assisted DES pretreatment showed excellent performance in achieving high xylan removal (86.7 %) and delignification (91.98 %). The pretreated bamboo was used for enzymatic hydrolysis and ethanol fermentation, with glucose yield and ethanol production of 76.13 % and 16.17 g/L, which was significantly improved by 30 % and 48 % compared to bamboo treated with corresponding binary TEAC/OA. The characterization of trinary pretreated bamboo revealed that the addition of polyols helped to protect the β-O-4 substructure of lignin, reduce the recondensation of lignin fragments, and thus enhance enzyme digestibility. Furthermore, 37.9% of lignin with high purity and highly active hydroxyl substructures was recovered. The proposed novel TEAC/OA-BDO DES mixture has great potential as an effective pretreatment solvent for future bamboo biorefinery.
合成了六种不同的氯化四乙铵（TEAC）/草酸（OA）-多元醇三元深层共熔溶剂（DES），以提高可发酵糖和木质素副产物的产量。三元DES预处理可以增强竹子的分级分离以及纤维素残渣的生物转化，其效率的提高与氢键供体中多元醇的烷基碳链长度和羟基数呈正相关。1,4-丁二醇（BDO）辅助的DES预处理在实现高木聚糖去除率（86.7%）和脱木质素率（91.98%）方面表现出色。预处理后的竹子用于酶水解和乙醇发酵，葡萄糖产率和乙醇产量分别为76.13%和16.17 g/L，与用相应二元TEAC/OA处理的竹子相比，分别显著提高了30%和48%。三元预处理竹子的表征表明，多元醇的添加有助于保护木质素的β-O-4亚结构，减少木质素片段的再缩合，从而提高酶消化率。此外，回收了37.9%具有高纯度和高活性羟基亚结构的木质素。所提出的新型TEAC/OA-BDO DES混合物作为未来竹子生物精炼的有效预处理溶剂具有巨大潜力。
