酸性盐酸胍基DES预处理对玉米秸秆酶解的影响  

Effect of Acidic Guanidine Hydrochloride DES Pretreatment on Enzymatic Hydrolysis of Corn Stalk

作　　者：李甜乐 吕东灿[2] 高婷婷 刘艳艳 王志敏[2] 宋安东[1] LI Tianle;LYU Dongcan;GAO Tingting;LIU Yanyan;WANG Zhimin;SONG Andong(Key Laboratory of Enzyme Engineering of Agricultural Microbiology,Ministry of Agriculture and Rural Affairs/College of Life Sciences,Henan Agricultural University,Zhengzhou 450046,China;School of Science,Henan Agricultural University,/Zhengzhou 450002,China)

机构地区：[1]河南农业大学生命科学学院,农业农村部农业微生物酶工程重点实验室,河南郑州450046 [2]河南农业大学理学院,河南郑州450002

出　　处：《林产化学与工业》2024年第6期140-150,共11页Chemistry and Industry of Forest Products

基　　金：国家重点研发计划资助项目(2021YFD1700900);河南省科技攻关项目(242102320360);河南省科技研发计划联合基金优势学科培育类重点项目(222301420008)。

摘　　要：为提高盐酸胍(GH)/乙二醇(EG)低共熔溶剂(DES)预处理生物质的效果,开展了以盐酸胍为氢键受体,乙二醇和柠檬酸(CA)等6种有机酸为氢键供体的DES体系预处理玉米秸秆的研究,考察了预处理前后秸秆组成和酶水解后糖产率变化,探讨了GH/EG/CA三元DES促进玉米秸秆酶解的机制。研究结果表明:6种有机酸均具有促进半纤维素和木质素脱除的作用,GH/EG/CA体系预处理效果最佳,其预处理玉米秸秆酶解72 h的还原糖产率为86.36%,分别是未处理和未加酸DES(GH/EG)预处理秸秆的3.3和1.8倍;预处理后纤维素回收率为94.21%,半纤维素和木质素的脱除率分别为65.14%和42.23%。利用扫描电镜、X射线衍射、物理吸附、红外光谱、热重及接触角仪等分析了预处理前后秸秆的形貌和结构。未处理、GH/EG和GH/EG/CA预处理玉米秸秆的表面粗糙程度、结晶度(I_(Cr))与比表面积均逐渐增大,是由于预处理后秸秆中纤维素含量增加,半纤维素和木质素组分溶解造成的;预处理后秸秆表面纤维素特征官能团更为丰富,热稳定性更好,水分渗透更快,从而实现了玉米秸秆的高效分离和转化,大大提高了木质纤维素的酶解效率;分解所得的葡萄糖可进一步通过发酵来产生生物基乙醇,木质素可进一步作为生物基材料的原料。To improve the pretreatment efficiency of biomass with guanidine hydrochloride/ethylene glycol deep eutectic solvents(DES),the research was carried out on the pretreatment of corn stalk using DES systems with guanidine hydrochloride(GH)as the hydrogen bond acceptor,and ethylene glycol(EG)and 6 organic acids as hydrogen bond donors.The variations in the composition of the stalk before and after pretreatment and the sugar yield after enzymatic hydrolysis were investigated,and the mechanism by which GH,EG,and citric acid(CA)DES(GH/EG/CA)facilitated the enzymatic hydrolysis of corn stalk was explored.The research results showed that all organic acids had the role of promoting the removal of xylan and lignin.The GH/EG/CA system exhibited the best pretreatment effect,with the reducing sugar yield of 86.36%after 72 h of enzymatic hydrolysis of the pretreated corn stalk,which were 3.3 and 1.8 times that of the untreated and DES-pretreated stalk without acid addition(GH/EG),respectively.The recovery rate of glucan after pretreatment was 94.21%,and the removal rates of xylan and lignin were 65.14%and 42.23%,respectively.The morphology and structure of the stalk before and after pretreatment were analyzed using scanning electron microscopy,X-ray diffraction,physical adsorption,infrared spectroscopy,thermogravimetry,and a contact angle meter,etc.The surface roughness,crystallinity(I_(Cr)),and specific surface area of the untreated,GH/EG and GH/EG/CA pretreated corn stalk increased gradually,which was attributed to the increase in cellulose content and the dissolution of hemicellulose and lignin components after pretreatment.After pretreatment,the characteristic functional groups of cellulose on the surface of straw were more abundant,the thermal stability was better,and the water penetration was faster,so as to realize the efficient separation and transformation of corn straw and greatly improve the enzymatic hydrolysis efficiency of lignocellulose.The resulting glucose can be further fermented to produce bio-based ethanol,a

关 键 词：盐酸胍 乙二醇 低共熔溶剂 纤维素 还原糖 

分 类 号：TQ35[化学工程]