作　　者： ; ; ; ; ;

机构地区： 华南理工大学材料科学与工程学院

出　　处： 《华东理工大学学报（自然科学版）》 2006年第6期666-671,共6页

摘　　要： 探索了生物催化反应制备酯化葡甘聚糖(KGM)衍生物的可能性,并构建了酶催化天然高分子改性的新模式。利用KGM与乙酸乙烯酯在无溶剂体系中的酯交换反应,对8种脂肪酶和5种蛋白酶的催化能力进行了初步评价,并考察了以固定化脂肪酶N ovozym 435作生物催化剂时,不同的非水介质对该反应的影响。结果表明:在本文条件下,这些酶对该反应均具有一定的催化作用;有机溶剂二甲基乙酰胺(DMA c)、甲苯(T o luene)和异辛烷(IOCT)以及其他非水相有机介质,如离子液体N-甲基-咪唑四氟硼酸盐[HM im]+[BF4]-和丁二酸二辛基磺酸钠(AOT)/异辛烷反相胶束体系,均有利于脂肪酶N ovozym 435催化的KGM与乙酸乙烯酯的酯交换反应。 This work aims at exploring the possibility of preparing for esterified konjac glucomannan （KGM） derivatives via a biocatalyzed reaction and establishing a new method for the enzymatic modification of a natural polymers. In order to select appropriate biocatalysts, the catalytic ability of 8 lipases and 5 proteinases were primarily evaluated by means of the transesterification of KGM with vinyl acetate in a solvent-free system. The effect of non-aqueous reaction media on the transesterification of KGM was in- vestigated with Novozym 435 as a biocatalyst. The results indicate that the enzymes used in the experiments possess catalytic activity for the reaction to a certain extent under the adopted conditions, and these organic solvents, dimethyl acetamide （DMAC）, toluene and isooctane （IOCT）, as well as the other nonaqueous organic media such as ionic liquid [-HMim]^＋[BF4]^- and a reverse micelle system AOT/IOCT, are all favorable for the Novozym 435-catalyzed transesterification of KGM with vinyl acetate.

关 键 词： 生物催化 葡甘聚糖 脂肪酶 酯交换反应 乙酸乙烯酯

领　　域： [化学工程]