褐藻降解菌群筛选及其复合酶固定化研究

以大连地区的褐藻为材料，筛选了褐藻降解菌群，其在30℃、pH7．5条件下培养74h时，酶活达1．883IU／mL。利用硅藻土吸附法经冷冻干燥制备了固定化复合酶，分析了复合酶系的酶学性质，其最适反应温度为45℃，并在40℃～55℃范围内具有良好的热稳定性；最适pH为7．5，并在pH7．0～8．5之间pH稳定性良好。利用固定化酶进行褐藻酸钠制备，提取率达48．3％，粘度为2．9Pa·s，与传统方法相比均有显著提高，为工程化生产褐藻酸钠提供一定基础。

Screening of algae degradation immobilized compound strains and their enzyme

The algae degradation strains were screened based on the brown algae from Dalian area. After being cultured for 74 h at 30 ℃ and pH 7.5, the compound enzyme activity was 1. 883 IU. The immobilized compound enzyme was made by freeze dry preparation and the properties of the immobilized enzyme were analyzed as follows ： the optimum temperature was 45 ℃, and the thermal stability was better between 40 ℃ ~ 55 ℃ ; the optimum pH was 7.5, and the pH stability was better between 7.0 - 8.5. The immobilized compound enzyme was then used to extract alginate. The results indicated that the extraction rate was 48.3% and the viscosity was 2.9 Pa .s. Compared with traditional methods, the data was sig- nificantly better than before and provided the basis for engineering production.