Mechanism of Enzymatic Hydrolysis of Poly(butylene succinate) and Poly(butylene succinate‐co‐L‐lactate) with a Lipase from Pseudomonas cepacia
Mechanism of Enzymatic Hydrolysis of Poly(butylene succinate) and Poly(butylene succinate‐co‐L‐lactate) with a Lipase from Pseudomonas cepacia
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DOI：
10.1002/mabi.200290002
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发表时间：
2002-12
影响因子：
4.6
通讯作者：
I. Taniguchi;Shigeyuki Nakano;Tetsuro Nakamura;Ahmed El-Salmawy;M. Miyamoto;Y. Kimura
中科院分区：
文献类型：
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作者：
I. Taniguchi;Shigeyuki Nakano;Tetsuro Nakamura;Ahmed El-Salmawy;M. Miyamoto;Y. Kimura
研究了一种来源于洋葱拟青霉的脂肪酶对聚丁二酸丁二醇酯（PBS）和聚丁二酸丁二醇酯-L-乳酸共聚物（PBSL）的酶解。结果表明，PBSL的拉伸纤维在脂肪酶的作用下易于水解，而PBS的拉伸纤维几乎不发生酶水解。由于PBS和PBSI的聚合物膜在相同条件下容易水解，因此酶促水解应不仅取决于结晶度，还取决于分子取向。样品的分子量随着孵育时间逐渐降低，因为即使在不存在脂肪酶的情况下，PBS和PBSL的主链上也发生非特异性水解。PBS和PBSL的酶促水解得到4-羟丁基琥珀酸酯（HBS）作为主要产物，在PBSL的情况下，具有痕量的琥珀酸和丁-1，4-二醇以及L-乳酸。此外，羧基封端的PBS的水解速率比原始的或羟基封端的PBS的水解速率慢得多，这些结果暗示了涉及从羧基末端的优先外切型断链的水解机制。
Enzymatic hydrolysis of poly(burylene succinate) (PBS) and poly (butylene succinate-co-L-lactate) (PBSL) has been studied by using a lipase originated from Paeudomonas cepacia. It has been found that the drawn fibers of PBSL are readily hydrolyzed by the action of the lipase, while, those of PBS undergo little enzymatic hydrolysis. Since the polymer films of PBS and PBSI are readily hydrolyzed under the same conditions, the enzymatic hydrolysis should depend not only on the crystallinity but also on the molecular orientation. The molecular weight of the samples gradually decreases with incubation time, because nonspecific hydrolysis occurs on the main chains of both PBS and PBSL even in the absence of lipase. The enzymatic hydrolysis of PBS and PBSL gives 4-hydroxybutyl succinate (HBS) as the main product with traces of succinic acid and butane-1,4-diol together with L-lactic acid in the case of PBSL. In addition, the hydrolysis rate of the carboxyl endcapped PBS is much slower than that of the original or hydroxyl end-capped PBS, These results imply a hydrolysis mechanism involving the preferential exo-type chain scission from the carboxyl terminals.