Selection of high efficient strains for decomposing cow manure and the optimization of fermentation formula

Chinese. 为了有效处理牛粪等高纤维废弃物，从牛粪发酵基质中分离分解纤维素优良的菌株，同时对筛选出的高产纤维素酶活菌株进行初步鉴定和发酵剂配方中氮源（棉粕、豆粕和尿素）的优化。结果表明，从牛粪堆腐发酵基质中分离出22株降解纤维素能力较强的菌株；依据综合性状从中优选出优良菌株Z5和Z8，初步鉴定其均为曲霉属真菌；在3个发酵剂配方中发酵培养72~96 h时，Z5在以棉粕为氮源的配方中有效菌数含量最高，而Z8在3个配方中的有效菌数差别不大，两菌株在3个配方中的有效菌数量均达到1014数量级；在以棉粕为氮源的配方中，菌株Z5和Z8均可获得最高的羧甲基纤维素酶活，其中Z5发酵培养72 h羧甲基纤维素（CMC）酶活最高，达4 463.57 μg/（g•min），Z8在发酵培养96 h时CMC酶活最高，达到3 265.67 μg/（g•min）。综合菌株生长状况得出，菌株Z5和Z8均可作为降解畜禽粪便发酵剂的优良生产菌株，棉粕是较为理想的固体发酵氮源。

English. In order to deal with high fibre wastes such as cow manure effectively, superior cellulose decomposing strains were isolated from cow manure fermentation substrate. The selected high activity cellulase of strains were identified and the nitrogen source (cottonseed meal, soybean meal, urea) of the components of the starter were optimized. The results showed that 22 strains that could degrade cellulose effectively were isolated from cow manure fermentation substrate. Z5 and Z8 were screened according to comprehensive characters and were identified as Aspergillus preliminarily. Fermented and cultivated 72-96 h continuously in the starters with three different nitrogen source respectively, there was the highest content of active bacteria in the cottonseed meal for Z5, while for Z8 there were small differences among the three starters. And the contents of active bacteria of the two strains all reached 1014. The highest carboxymethyl cellulose activity was acquired in the starters with cottonseed meal as nitrogen source.When Z5 was cultured 72 h, the carboxymethyl cellulose activity was the highest and could attain to 4 463.57 μg/（g•min）, while for Z8 was 96h, it reached 3 265.67 μg/（g•min）. In conclusion, Z5 and Z8 can be used as superior strains for degrading animal manure, and cottonseed meal is the ideal nitrogen source of solid fermentation.