一组降解木质纤维高温混合菌相关酶活的研究

Study on Enzyme Activity of High-temperature Composite Microbe for Degrading of Lignin and Cellulose

采用从高温堆肥和枯枝落叶等混合样中筛选出的一组高温混合菌处理玉米秸秆基质,研究混合菌对玉米秸秆降解过程中的木质素酶活和纤维素酶活,以及不同纤维素碳源和pH对其产纤维素酶的影响。结果表明,在50℃,30 d的降解周期内,第15天木质素酶活和纤维素酶活达到最高,对应的漆酶酶活为10.2 U/g、羧甲基纤维素酶活(CMCase)为5.7 U/g、滤纸酶活(FPA)为3.2 U/g;当pH为7、微晶纤维素为碳源时纤维素酶活最高,CMCase酶活和FPA酶活分别达到690和360 U/L。该混合菌既能分泌木质素酶,又能分泌纤维素酶,有较强的木质纤维降解能力。

Using a set of high-temperature composite microbe which was isolated from mixed samples of compost and litter to degradate the corn straw substrate, the lig^in activity and cellulose activity were studied in the degradation process of corn stover, and the effects of differ- ent cellulosic carbon source and pH on the capability of enzyme production of composite microbe were investigated. The results showed that lignin activity and ceUulase activity reached the highest after 15 days at 50 ℃ in 30 days degradation period, corresponding Lac activity, CMCase activity and FPA activity were 10.2, 5.7, 3.2 U/g, respectively. Cellulaso activity reached the highest when the microcrystalline celluloso was carbon source and pH was 7, and CMCase activity and FPA activity was 690 and 360 U/L, respectively. The mixed bacteria could not only secrete ligninolytic enzyme but also secrete cellulase and had strong ability of lignocellnloso degradation.