染料废水生物膜中酶的作用特性与条件优化

Study on enzyme properties and optimization of enzyme activity conditions in dye wastewater biofilm

通过对兼氧-好氧染料废水处理系统兼氧生物膜中脱氢酶、脂肪酶和酯酶的活性分析，研究了3种酶的作用特性以及最佳条件优化。试验结果表明，脱氢酶作为一种胞内酶，在出水水样中仍能检测到2．2％的活性存在；82．5％脂肪酶和79．9％的酯酶分布在生物膜中，这说明绝大多数脂肪酶和酯酶是与细胞相连或固定在细胞外多聚絮体基质中。0．4mmoL／L的抑制剂EDTA对脱氢酶活性有促进作用，而对脂肪酶和酯酶的抑制率分别达到59．8％和18．9％。正交试验结果表明，待测3种酶有最大活性的条件均为：温度为60℃，底物浓度为50／zmol／L，pH为8，在优化条件下待测酶活性可达常规作用条件的2．58～6．44倍。各因素对待测酶活性的影响强弱排序为：温度〉底物浓度〉pH。

The properties and optimization of the conditions of dehydrogenase, lipase and esterase in biofilm for a facultative-aerobic dye wastewater purification process were investigated. Results showed that the intracellular enzyme 2.2% of dehydrogenase activity was detected in the supernatant and about 82.5% of lipase activity and 7.9.9% of esterase activity were associated with microbial cells in the biofilm. An increase of dehydrogenase activity occurred and inhibitories of 59.8% and 18.9% to lipase and esterase activities were observed after the addition of 0.4 mmol/L inhibitor EDTA in the mixture. The results of orthogonal experiments indicated that the optimum enzymatic activity conditions of the three enzymes were shown as followings： temperature of 60 ℃ , substrate concentration of 50/μmol/L and pH of 8. Under these conditions enzymatic activities reached 2.58 -6.44 times higher than that under the normal conditions. The key factors affecting the enzymatic activities were arranged ： temperature 〉 substrate concentration 〉 pH value.