Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia.
Department of Chemistry, College of Science and Arts at Khulis, University of Jeddah, Jeddah 21921, Saudi Arabia.
Int J Mol Sci. 2023 Jan 19;24(3):1970. doi: 10.3390/ijms24031970.
Lipases are extensively utilized industrial biocatalysts that play an important role in various industrial and biotechnological applications. Herein, polyacrylonitrile (PAN) was treated with hexamethylene diamine (HMDA) and activated by glutaraldehyde, then utilized as a carrier support for lipase. In this regard, the morphological structure of modified PAN before and after the immobilization process was evaluated using FTIR and SEM analyses. The immobilized lipase exhibited the highest activity at pH 8.0, with an immobilization yield of 81% and an activity of 91%. The optimal pH and temperature for free lipase were 7.5 and 40 °C, while the immobilized lipase exhibited its optimal activity at a pH of 8.0 and a temperature of 50 °C. After recycling 10 times, the immobilized lipase maintained 76% of its activity and, after 15 reuses, it preserved 61% of its activity. The lipase stability was significantly improved after immobilization, as it maintained 76% of its initial activity after 60 days of storage. The calculated Km values were 4.07 and 6.16 mM for free and immobilized lipase, and the Vmax values were 74 and 77 μmol/mL/min, respectively. These results demonstrated that synthetically modified PAN is appropriate for immobilizing enzymes and has the potential for commercial applications.
脂肪酶是广泛应用的工业生物催化剂，在各种工业和生物技术应用中发挥着重要作用。本文中，用己二胺（HMDA）对聚丙烯腈（PAN）进行处理并用戊二醛进行活化，然后将其用作脂肪酶的载体支撑物。在这方面，通过傅里叶变换红外光谱（FTIR）和扫描电子显微镜（SEM）分析评估了固定化过程前后改性 PAN 的形态结构。固定化脂肪酶在 pH 值为 8.0 时表现出最高的活性，固定化产率为 81%，活性为 91%。游离脂肪酶的最适 pH 值和温度分别为 7.5 和 40°C，而固定化脂肪酶在 pH 值为 8.0 和温度为 50°C 时表现出最佳活性。重复使用 10 次后，固定化脂肪酶保持了 76%的活性，在 15 次重复使用后，它保持了 61%的活性。固定化后，脂肪酶的稳定性得到了显著提高，在储存 60 天后，它保持了 76%的初始活性。游离和固定化脂肪酶的 Km 值分别为 4.07 和 6.16 mM，Vmax 值分别为 74 和 77 μmol/mL/min。这些结果表明，合成改性的 PAN 适合于固定化酶，具有商业应用的潜力。
