朽木来源纤维素分解细菌·真菌混合秸秆纤维发酵研究

Research on the Bacteria for the Decomposition of Cellulose and Straw Cellulose Fermentation of Fungi

[目的]为研究朽木生态小环境中各种微生物之间的相互作用和农业废弃秸秆的再利用奠定基础。[方法]利用分离的几株来源于云贵高原地区次生林朽木中具有较高纤维素分解活性的细菌(B2、Q1)、真菌(W9)与放线菌(H1)分别和混合发酵纤维素羧甲基纤维素钠和滤纸等底物,研究碳源种类、培养时间对纤维素分解酶活的影响。[结果]分离的4株菌及混合菌在4种碳源上均能良好生长,其中B2和H1在羧甲基纤维素钠为碳源培养72h的纤维素酶活性最高,分别为61.9 U和57.7U;混合菌在各种碳源中发酵活力均较低;混合发酵较不同菌株单独发酵产生还原糖总量略有降低;在以玉米秸秆为唯一碳源的培养基上各种菌的纤维素分解酶活性随培养时间的延长逐渐增加。[结论]混合菌的纤维素分解活性均低于各种菌单独发酵。

[ Objective] The foundation of the research on the interaction of micro-organisms in the ecological environment of deadwood and the re-use of waste crop straw was laid. [ Method] Several of the bacteria（B2, Q1 ）, fungi （wg） and actinomyceles （H1）,which were with the high activity of decomposition of cellulose,were isolated from the rotten wood from secondary forest areas of the Yunnan-Guizhou Plateau and they were mixed with carboxymethyl cellulose-Na and filter paper etc to research the effect of the type of carbon and culturing time on the activity of the decomposition enzyme of cellulose. The 4 bacteria isolated and their mixture can grow well in 4 types of carbon source, among which, the activity of the decomposition enzyme of cellulose of B2 and H1 cultured for 72h was highest on CMC carbon source（61.9U and 57.7U, respectively） and the activity of the mixture of bacteria was low in any type of carbon source. The total of of reducing sugar from the fermentation of the mixture of bacteria was lower than that from the fermentation of a variety of bacteria.The activity of the decomposition enzyme of cellulose of all bacteria cultured in the medium with the corn stalk as only source was gradually raised with the prolonging culture tine. [ Conclusion] The activity of the decomposition enzyme of cellulose of the mixture of bacteria was lower than that from the fermentation of single bacteria.