Medical Biotechnology, College of Medicine and Public Health, Flinders University, Bedford Park, Adelaide, SA 5042, Australia.
Mar Drugs. 2024 Mar 4;22(3):120. doi: 10.3390/md22030120.
Alginate lyase (AL) is a polysaccharide-degrading enzyme that can degrade alginate by hydrolyzing glycosidic bonds and produces unsaturated alginate oligosaccharides (AOSs). These AOSs have wide therapeutic and nutraceutical applications. However, to produce alginate oligosaccharides in a cost-effective manner is challenging due to the low availability and high cost of this degrading enzyme. Immobilization of the enzyme facilitates industrial applications owing to its stability, reusability, and cost-effectiveness. This study was focused on the enhancement of the properties of alginate lyase and improvement of the production of AOS. Alginate lyase was immobilized on magnetic nanoparticles (NPs) using glutaraldehyde as the crosslinker. The study showed that the maximum binding achieved between NPs and protein in the enzyme was 71% at a ratio of 1:150 NP:protein. As a result of immobilization, the optimum activity of free enzyme which was obtained at 37 °C and pH 7.4 changed to 45 °C and pH 9. Furthermore, the enzyme was thermostable at 45 °C for 3 h with up to 50% reusability for six consecutive cycles. Storage stability after 15 days showed ~67% relative hydrolysis of alginate. The free alginate lyase (25 IU) showed 76% raw biomass (seaweed) hydrolysis which is higher compared to 63% provided by the immobilized enzyme. As a result of efficient hydrolysis, AOSs with molecular weight profile of 370-1040 kDa were produced and detected using HPLC.
海藻酸盐裂解酶（AL）是一种多糖降解酶，能够通过水解糖苷键将海藻酸盐降解，并产生不饱和的海藻酸盐低聚糖（AOSs）。这些 AOSs 在治疗和营养保健品方面具有广泛的应用。然而，由于这种降解酶的可用性低、成本高，因此以经济有效的方式生产海藻酸盐低聚糖具有挑战性。由于其稳定性、可重复使用性和成本效益，该酶的固定化有利于工业应用。本研究专注于增强海藻酸盐裂解酶的性能并提高 AOS 的产量。使用戊二醛作为交联剂将海藻酸盐裂解酶固定在磁性纳米颗粒（NPs）上。研究表明，在 NPs:蛋白质比例为 1:150 时， NPs 与蛋白质之间的最大结合量达到 71%。固定化后，游离酶在 37°C 和 pH7.4 下获得的最佳活性变为 45°C 和 pH9。此外，该酶在 45°C 下稳定 3 小时，在六个连续循环中具有高达 50%的可重复使用性。15 天后的储存稳定性显示出约 67%的相对海藻酸盐水解率。游离的海藻酸盐裂解酶（25IU）显示出 76%的原始生物质（海藻）水解率，高于固定化酶提供的 63%。由于高效水解，使用 HPLC 检测到分子量分布为 370-1040kDa 的 AOSs。
