This work presents a novel lipase immobilization method via polylactic acid (PLA) modified by polyethylene glycol (PEG). The immobilization performance of lipase was characterized by SEM and FTIR. The results indicated that lipase from Candida rugosa type VII was successfully immobilized on the biocompatible PLA/PEG film in the presence of 1, 6-hexamethylene diamine and glutaraldehyde. In addition, the presence of 1, 6-hexylenediamime (8%, w/w) could maintain the maximum enzymatic activity. Moreover, the optimum temperature of lipase shifted from 45 to 50 °C after immobilization. The thermal inactivation experiment illustrated that the immobilized lipase retained up to 63% of the original activity after treated at 50 °C in buffer for 120 min, significantly higher than that of the control (33%) (p < 0.05). The optimum pH value of the immobilized lipase shifted from 6.5 to 7.5. Additionally, compared with the free lipase maintaining 23% of its original activity, the immobilized lipase successfully retained up to 70% after 30 days of storage. Furthermore, the immobilized lipase displayed the excellent reusability of 82% after six cycles. In conclusion, the proposed immobilization approach developed can be potentially used as a sustainable alternative for the immobilization of lipases and the utilization of biocompatible polymer. Graphical Abstract.

中文翻译：

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聚乙二醇（PEG）修饰的聚乳酸（PLA），用于固定脂肪酶。

这项工作提出了一种通过聚乙二醇（PEG）修饰的聚乳酸（PLA）固定脂肪酶的新方法。用SEM和FTIR表征了脂肪酶的固定化性能。结果表明，在1，6-六亚甲基二胺和戊二醛存在下，来自七型念珠菌的脂肪酶已成功固定在生物相容性PLA / PEG膜上。此外，1，6-己二烯二胺（8％，w / w）的存在可以保持最大的酶活性。此外，固定后，脂肪酶的最佳温度从45变为50℃。热灭活实验表明，固定化脂肪酶在50°C的缓冲液中处理120分钟后，保留了高达63％的原始活性，显着高于对照（33％）（p <0.05）。固定化脂肪酶的最佳pH值从6.5变为7.5。此外，与游离脂肪酶保持其原始活性的23％相比，固定化脂肪酶在储存30天后可成功保留高达70％的脂肪。此外，固定化的脂肪酶在六个循环后显示出82％的出色重用性。总之，提出的固定化方法可以潜在地用作脂肪酶固定化和生物相容性聚合物利用的可持续替代方法。图形概要。总之，提出的固定化方法可以潜在地用作脂肪酶固定化和生物相容性聚合物利用的可持续替代方法。图形概要。总之，提出的固定化方法可以潜在地用作脂肪酶固定化和生物相容性聚合物利用的可持续替代方法。图形概要。