| With the surge in world population, food and energy shortages will become increasingly serious, the renewable development and utilization of renewable plant fibers caused widespread concern around the world. The annual production of crop straw in China as much as up to 700 million tons, estimated there are approximately 90% of cellulose resources can not be used, most are burned for nothing, but bring enviromental problems. The main components straw cellulose, hemicellulose and lignin, the latter as the main component of cell walls of straw is usually difficult to microbial decomposition, thus limiting the degradation and utilization of these components. If the lignin can be degraded effectively, the chimeric structure of cellulose, hemicellulose and lignin can be changed, and then makes it probable to transform the straw into easily absorbed feedstuff. The crop straw as one of renewable resource, in particular, corncob and corn stalks in China has a wide distributin, large quantity and variety, low price and so on. How to take full advantage of those resources, and make no enviromental polution, is one of difficulties faced in modern agriculture.In order to make better use of corn cob, corn stalks and other agricultural waste, improve the comprehensive utilization efficiency, reduce the traditional chemical methods and process of environmental pollution caused by waste incineration; we screened a variety of ligninase-producing microorganism, first the Coprinus comatus, Aspergillus niger and Trichoderma reesei through mixed plate screening. The results showed that C. comatus mixed cultured with T. reesei had a good compatibility and high level of Laccase. The optimal conditions for enzyme producing were studied on the basis of the compatibility of Coprinus and Trichoderma reesei. The optimal conditions for enzyme production: Coprinus comatus mycelium suspension and Trichoderma reesei spore suspension inoculated by 5:2 ratio, time interval vaccination 12h, at 26℃, pH 5.0, 150 r/min, for 3 days, at those condition laccase activity reached 3267.1 U/ml, increased by 106% compared with single culture of C. commatus. Then the production of ligninase from mixed fermentation with T. reesei and C. comatus were used to degrade straw and other waste whose enzymolyzed production was converted into L-lactic acid by Rhizopus oryzae. Then the agricultural wastes were treated 84 hours with the cude enzymes extracted from the 3d mixed fermentation of T. reesei, C. comatus at pH 5.0, 50℃, 120r/min, and 55.2% enzmymolysis reducing sugar were obtained. Then the enzmymolysis reducing sugar were converted into L-lactic acid by R. oryzae. Under the optimal condition, 3.36g/L L-lactic acid were produced and the sugur conversion rate reached to 67.40%.Meantime, in order to produce high-quality and low-cost livestock feed, solid-state secondary fermentation using agricultural wastes after first fermentation were studied in this paper. The fermentated solid medium corn flour is 9:1. We analyzed the changes of various components in solid substrate after mixed solid-state fermentation, such as cellulose, hemicellulose, lignin and protein. The results showed that at the inoculation proportion of C. comatus (diameter 2mm colony) and T. reesei (suspention of spores, 1×10~7) is 6:1, the initial pH 7.0, the ratio of materia to water is 1:1.5. The contents of cellulose, hemicellulose, lignin and protein in solid substrate after mixed solid-state fermentation for 12d is 13.44%,14.11%,3.11% and 26.73%, respectively. The degradation rate of the former 3 components reached 47.2%,49.9%,47.3%, the content of protein is nearly 5 times more than that in unfermentation medium, which is 26.73%.In the studies, the agricultural waste, which is lignocellulose-rich, can be degradated efficiently and pollution-free, and can be transform to nutrient-rich, easly digested microorganism protein feed. The process can be used for providing cheaper sources of feedstuff in animal husbandry.
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