The presence of various contaminants in foodstuffs has led to serious public health concerns. Diamine oxidase (DAO) has attracted tremendous attention for guarding food safety as well as clinical and environmental industries. In this study, DAO from Pisum sativum (Pea) seedlings was extracted and purified by dialysis and gel filtration. Purified DAO was covalently immobilized onto the surface of nitrocellulose membrane using glutaraldehyde. The obtained bioaffinity support has efficiently shown high yield immobilization of DAO from pea seedlings. The optimal conditions of free and immobilized DAO activity were evaluated against the substrate, Putrescine dihydrochloride. The influence of pH, temperature, storage stability, and reusability of immobilized enzyme with comparison to the free enzyme was studied and the results showed that the stabilities were significantly enhanced compared with free counterpart. Residual activity of the immobilized enzyme was 59% of the initial activity after being recycled 10 times. We approve that this novel low cost immobilized DAO carrier presents a new approach in large scale applications.

中文翻译：

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使用活化纤维素薄膜有效固定纯化的二胺氧化酶以增强酶性能和稳定性的新方法。

食品中各种污染物的存在导致了严重的公共卫生问题。二胺氧化酶（DAO）在保护食品安全以及临床和环境工业方面引起了极大的关注。在这项研究中，从豌豆（Pisum sativum，豌豆）幼苗中提取的DAO通过透析和凝胶过滤进行提取和纯化。使用戊二醛将纯化的DAO共价固定在硝酸纤维素膜的表面上。所获得的生物亲和支持物已有效地显示了豌豆幼苗中DAO的高产量固定化。针对底物腐胺二盐酸盐评估了游离和固定的DAO活性的最佳条件。pH，温度，储存稳定性的影响 研究了固定化酶与游离酶的可重复使用性，结果表明，与游离酶相比，其稳定性大大提高。回收10次后，固定化酶的残留活性为初始活性的59％。我们赞成这种新颖的低成本固定式DAO载体在大规模应用中提出了一种新方法。