【摘要】 对球磨的杠柳(Periploca sepium)采用含有0.05mol/L HCl的80%液体二氧六环在85℃处理4h、二甲基亚砜在85℃处理4h,以及8%NaOH在50℃处理3h,得到86%的原本木质素。采用FTIR、UV、液态1H和13C-NMR研究了酸性二氧六环、二甲基亚砜和碱溶性木质素组分的结构特征。结果表明:温和条件下,球磨与酸水解对分离的木质素大分子结构破坏不大。其中,温和酸水解使半纤维素和木质素之间醚键发生显著断裂,并使半纤维素发生部分降解。由于酸性二氧六环溶解的木质素主要来自初生壁,而碱溶性木质素主要来自次生壁,导致酸性二氧六环溶解的木质素与二甲基亚砜和碱溶性木质素结构不同。更多还原

【Abstract】 A total release of over 86 percent of original lignin from the mild ball-milled Periploca sepium was obtained after sequential treatments with 80% aqueous dioxane containing 0.05 mols per liter HCl at 85 degrees C for 4 hours,dimethyl sulfoxide(DMSO)at 85 degrees C for 4 hours,and 8 percent NaOH at 50 degrees C for 3 hours.The structures of the acidic dioxane-,DMSO-,and alkali-soluble lignin fractions were analysed using FTIR,UV,solution-state 1H and 13C NMR techniques.Results showed that both the mild ball milling and the mild acidolysis under the given conditions had little effect on the macromolecular structure of separated lignin.The mild acidolytic hydrolysis condition caused substantial hemicellulosic depolymerization except for a significant cleavage of the ether linkages between lignin and hemicelluloses.The acidic dioxane-soluble lignin fraction was structurally different from DMSO-and alkali-soluble lignin preparations,and might originate mainly from the primary wall,while the alkali-soluble lignin preparation was mainly released from the secondary wall of Periploca sepium.更多还原