| The missions of agricultural waste increased dramatically with economic development. Composting, as a technology of agricultural waste utilization, has been paid a lot attention to because of its decontamination, reduce and recycle. But traditional composting has no good effect because composting substances contain lignocellulose that hardly to degrade Lignocellulose as refractory organic matter in compost is considered the key of fast compost and is degraded by enzymes function, so it is essential to research on dynamic changes of crucial degradation enzymes and its regular pattern in the system of compost. At the same time, during the composting, the raw material is transformed through a variety of biological and biochemical processes in which enzymes play an important role. Enzymes that catalyze the degradation of biomacromolecules, such as starch, protein, cellulose, hemicellulose and lignin, are extracellular enzymes since the biomacromolecules are too large to be transported across the cellular membrane. So the adsorption of extracellular enzymes on surface of substances has influenced on degradation of lignocellulose and transportation of extracellular enzymes to the depth of compost. Therefore, it is obvious that research on the characteristic of adsorportion of key enzymes on compost substances will promote mechanism study, which will in turn speed up the composting process and enhance the quality of compost.In this experiment, adding enzyme solution into pilesize was studied compared with unadding enzyme solution into pilesize. The degradation rate of hemicellulose, cellulose and lignin, changes of organic matter, and enzyme activity were monitored during composting and the effect of enzyme on the degradation of lignin was investigated. The results indicated that exogenous enzymes can promote secretion of LiP, MnP and PPO by microorganism, but inhibit the product of POD by microbe to some extent. In the pilesize adding enzyme the content of lignocellulose and organic matter were significantly lower than that of the pilesize not added enzyme. The results suggested that exogenous enzyme could enhance the degradation of lignocellulose. We found the degradation of lignocellulose was finished under synergistic effect of various enzymes and was influenced by other factors. To understand the characteristics of ligninolytic enzymes sorption in different compost substances, ligninolytic enzymes adsorption on soil, vegetable leaf, rice straw and chaff was comparatively studied through batch jar tests and the relevant kinetics and isotherm equilibrium were discussed as well as optimization pH and temperature. The results showed that the sorption efficiency was depended on the sorts of substances. The adsorptive capacities of soil, vegetable leaf, rice straw and chaff to lignin peroxidase (LiP) were 1.22 U/g,1.27 U/g,1.13 U/g,1.22 U/g and to manganese peroxidase (MnP) were 5.09 U/g,4.88 U/g,4.43 U/g,3.95 U/g, respectively. The best temperature is about 30℃and the best pH is about 4-5. Comparing the kinetic models of LiP and MnP adsorption, the psendo-second-order reaction model (R2= 0.973～0.9997) was the best of the models. Elovich equation was a bit better than pseudo-first-order kinetic which was the worst. The equilibrium data could be fitted well with Langmuir model while it couldn't satisfied with Freundlich model. The adsorptive saturation of soil, vegetable leaf, rice straw and chaff to LiP were 1.23 U/g,1.30 U/g,1.17 U/g,1.14 U/g and to MnP were 5.70 U/g,5.19 U/g,4.73 U/g,4.14 U/g. The fourier transform infrared (FTIR) spectroscopy demonstrated that adsorption of LiP and MnP onto compost substances have relation with active functional group such as tri-methyl, alkyl radical, carboxyl and amino group.
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