Selection and Construction of Composting Consortia for Degrading Lignocellulose Efficiently and Its Capability of Straw Degradation

A composite consortia with higher capacity of degrading lignocellulose were selected and constructed from different samples of high temperature stage in compost. It was obtained with the principle of compensation of acid and alkali, and by optimization and combination of different systems. The capability of cellulose degradation of microbial community was investigated with filter paper, absorbent cotton , rice straw and sawdust by the way of CMC-Na saccharogenic powder and gravimetry. The result showed that the composite microbial system could directly degrade carbon source with high native cellulose content (such as filter paper and cotton). By contrast that the degradation of sawdust was lower for it had higher content of lignin and lower cellulose. With the rice straw as the sole carbon source to test the degrading capacity, it showed that the microbial system could degrade dissolved sugar and starch more effectively than cellulose and hemicellulose at the initial stage of fermentation. In the first 3 days the content of dissolved sugar and starch reduced 58.5% and 30.44% respectively, and by the end of fermentation they reduced 72.91% and 47.85% respectively. During the whole period of fermentation, the changes of straw weight and pH of fermenting liquer are identical, and in the initial 5 days the microbial system has higher decomposing activity. By the end of fermentation, the contents of cellulose and hemicellulose reduced 7.39% and 43.76% respectively, while the lignin content had little change.