| Lignocellulose is the most abundant resource of photosynthesis product in the world, but a more part of ligocellulose becomes the waste because of its property of being degraded toughly. Technique of microbial pure culture can not resolve the puzzle of lignocellulose degradation. A composite bacterial system WSC-6 with high capacity of lignocellulose degradition was constructed by the techniques of limited cultivation. It was found that 0.5 percent of filter paper of fermentation liquid could be degraded by WSC-6 at 50℃ within 72 hours under static culture. More than 99 percent of cellulose content of treated rice straw of 0.5 percent of fermentation liquid was degraded at 50℃ within 8 to 10 days under static culture. Nine bacterial isolates and five bands of 16S rDNA gene on Denaturing Gradient Gel were obtained though methods of plate culture and Denaturing Gradient Gel Electrophoresis (DGGE). Its were Pseudoxanthomonas taiwanensis, Tepidiphilus margaritifer, Bacillus sp. E53-10, Proteobacterium S072, Beta proteobacterium HMD444, Rhizobiaceae str. M100, Petrobacter succinimandens BON4, Bacillus thermoamylovorans, Paenibacillus macerans, Ureibacillus thermosphaericu, Uncultured bacterium clone GW6, Uncultured Clostridium sp. clone A1-3, C. thermobutyricum and Clostridium thermosuccinogenes, respectively. It was showed that composite bacterial system WSC-6 was composed of uncultured and cultured bacteria, and fungus and streptomyces were not detected. It was detected that bacterial compose of generations subcultured more than two years was very stable, and capacity of degrading cellulose was not declined under the conditions of treated at temperature between 70℃ to 95℃ for ten minutes, and preservation of dry, freeze and liquid at 4 ℃ for two years. The optimum oxygen concentration for cellulose degradation was 0.07-0.16 mg· L-1.Effect of composite bacterial system WSC-6 as a kind of inoculant on the process of composting was evaluated in the experiment. The results showed that degradation speed of hemicellulose, cellulose and lignin in the inoculated treatment was quickened, and duration for maturing of composting was shortened compared with non-inoculated treatment. The pattern of DGGE bands showed that only when was the condition of goal environment matched well with optimum condition for inoculant growth, the process of composting could be improved by inoculant.It was discovered that the degrading speed of cellulose was speed up at the forepart of the process of composting under the micro-aerobic condition of oxygen concentration below 1.5 percent so that the duration of maturing of compost was shortened compared with the aerobic composting. Therefore, the opinion of one phase fermentation under the micro-aerobic composting was supposed compared with the shortage of the aerobic composting. The main body included that degradation of lignocellulose was applied as a criterion of estimating the maturity of compost. Lignocellulose was degraded continuously and rapidly under the micro-aerobic composting so that the duration of maturing of compost was decreased by 10 days, and there was no a typical second phase of fermentation compared with the aerobic composting. Loss of N was less and energy consumed was saved during the micro-aerobic composting compared with the aerobic composting.
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