绿色糖单孢菌降解木质纤维胞外酶的分泌条件及其生物漂白研究

以一株耐热耐碱放线菌-绿色糖单孢菌（Saccharomonospora viridis）为研究对象，探讨其产胞外木素过氧化物酶、木聚糖酶、纤维素酶的优化发酵条件。结果表明，其最佳碳氮源分别为葡萄糖和蛋白胨，最佳接种量为1％，不同的诱导底物对三种木质纤维降解酶有不同的诱导效果，其中麦草浆的诱导效果最好。在培养基中添加0．01mol／L的Mn^2＋和0．1％的土温80能够显著促进木质纤维降解酶的产生。在pH8．0，45℃条件下，培养120h后木素过氧化物酶的酶活达到最大0．36U／mL，培养156h后木聚糖酶和纤维素酶的酶活达到最大，最高酶活分别为18．46U／mL，10．42u／mL。用含有这三种酶的粗酶液对麦草烧碱蒽醌浆进行生物漂白表明，绿色糖单孢菌所产的木质纤维降解酶具有较好的漂白效果。

Studies on fermentation conditions of extracellular ligninocellulose-degrading enzymes from Saccharomonospora viridis and biobleaching

Optimum fermentation conditions of extracellular lignoceUulose-degrading enzymes from an actinomyces Saccharomonospora viridis with the characteristics of both thermotolerance and alkali-tolerance were studied. The results showed that the optimum carbon and nitrogen sources were glucose and peptone, respectivdy. In the aspect of induction of lignocellulose-degrading enzymes, the wheat straw was more preferable than veratryl alcohol, and the compound substrate than the single. In addition, the activitiy was strongly enhanced in the presence of 0.01 mol/L Mn^2＋ and 0.1% Tween80. Optimum production of lignin peroxidase was achieved after the duration of 120 hours at 45 ℃ and initial pH8.0, while xylanase and cellulose was both achieved after 156 hours of incubation. Biobleaching of wheat straw soda-AQ pulp with extracelMar enzyme of Saccharomonospora viridis was also studied. It was found that the crude enzyme containing xylanase, lignin peroxidase and little cellulose showed high bleaching activity, which was an important consideration for pulp and paper industry.