| Now, composting has become a technology of agricultural and forestry waste utilization . The agricultural and forestry waste can be recycled by composting. We can get a good ecomonic benefit, realize the clean production, and protect the environment from pollution. The waste treatment technology of composting entered a new stage of science development. In order to improve the disadvantage of composting, increase the compost efficiency, and make it can be used in large scale, many researchers at home and abroad carried out a lot of research on the field of composting equipment, composting technology, and microbiology of composting, et al. The biodegradation of limits speed organic compound is considered as the key of composting. In agricultural and forestry composting, the lignocellulose is the major organic compound that limiting composting speed. This organic compound has hard structure, and is separated difficultly. Especially the lignin, it is considered the key of fast compost, its degradation is essential for the operation of compostingSince lignin is the major organic compound that limiting composting speed, its degradation is essential for the operation of composting.Phospholipid fatty acid (PLFA) and Partial Least- squares Regression (PLS) methods were selected to establish the quantitative regressive model between lignin content and PLFA. Through the analysis of model parameters, it was found that a few microorganisms with strong lignin degrading ability and plentiful microbes with weak lignin degrading ability cooperated during the composting of agricultural wastes. The former were fungi and actinomycetes that dominant in lignin degradation, while the latter was bacteria. Microbial species were believed to be more important than amounts. During the thermophilic phase, the effective lignin degrading microbial proportion was 42∶35∶6∶17 (Gram-positive bacteria∶Gram-negative bacteria∶actinomycetes∶fungi), while the proportion was 58∶23∶41∶5 during the maturation phase of composting. The microbial content was about 108cells/g dw.Five strains of microorganisms were isolated from the agricultural waste composting, They were identified as Bacillus subtilis, Pseudomonas aeruginosa, Aspergillus niger, Penicillium simplicissim, Streptomyces badius. By way of being found to be capable of utilizing several lignin model compounds, these strains were proved that they had the ability to decompose the hycroxybenzene and nonhydroxybenzene lignin compounds of low molecular weight. For developing a kind of high efficiency of microbe inocula in compost, this research had an inoculation with the five fungus according to different quota to natural rice-straw, after 30 days solid-state fermentation.The results showed that the mixed fungus had ligninolytic ability which was furthered proved by the analyses of enzyme production. Five kinds of enzymes, lignin peroxidase, manganses peroxidase, laccase, cellulase and hemicellulase were believed to be the most important catalyzes in biodegrading process, and they always worked synergistically. When the quota of bacteria∶Actinomycete∶fungus is 85∶5∶10; Bacillus subtili∶sPseudomonas aeruginosa is 55∶25; Aspergillus niger∶Penicillium simplicissim is 2∶1, the degradation rates of lignin,cellulose and hemicellulose were the highest, being 2.13%,48.97%,55.93% respectively after 30 days incubation.In the condition of not being sterilized, relative to not being inoculated, the experiment being inoculated according to this ratio made the degradation rates of lignin,cellulose and hemicellulose increase 9.16%, 38.25%,46.30% respectively after 30 days solid-state fermentation.
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