中文摘要：

以壳聚糖微球为载体，戊二醛为交联剂固定化血管紧张素转化酶，研究了酶固定化的最优条件和固定化酶的性质．结果表明，在戊二醛质量分数为2．5％、给酶量为8mg／mL时，固定化酶的比活性最大，为0．085U／g．固定化酶在40～50℃，pH在7～9之间有最大活性，其米氏常数Km为2．39mmol／L．同时，固定化酶具有良好的稳定性，可重复利用．

英文摘要：

Chitosan is a polysaccharide which is widely used in enzyme immobilization as a support. Angiotensin converting-enzyme（ACE） is an important member of the rennin-angiotensin-aldosteronesystem which could cause high blood pressure. In this study, ACE was immobilized on chitosan microspheres with glutaraldehyde as cross-linking reagent. The optimum conditions and properties of immobilization enzyme were investigated. The max ratio activity was 0. 085 U/g under 2.5% glutaraldehyde and 8 mg/mL soluble enzyme for immobilized enzyme. The optimum pH, temperature and K,n of the immobilized enzyme were 7---9, 40--50℃ and 2.39 mmol/L. The immobilized ACE show higher thermal stability and can be used repeatedly to a certain extent. It was a fundamental study in order to develop the way of screening ACE inhibitor.