| Since microorganism, and lignocellulose, which is difficult to be degraded, are of great importance of technique improvement and efficiency enhancement during agricultural waste composting. The relationships between the succession of microbial community and degradation of lignocellulose were studied by analyzing in physico-chemical properties, enzymology, microbial community based on culture-independent method during agricultural waste composting. Kinds of culture-independent methods and statistical method were synthetically used for analyzing microbial community. Based on the characteristic and rules in composting, preponderant microorganisms selected in different stage during composting were developed to compound microorganism.To investigate the changes of microbial communities and influence of Phanerochaete chrysosporium during solid-state fermentation (SSF) of rice straw, phospholipid fatty acids (PLFA) and lignocellulose components were measured with periodical sampling. The results showed that the lignocellulose degrading ratios in SSF which was inoculated by P. chrysosporium and soil microorganisms were higher than those degraded by culturing a single species. The total amount of PLFAs, as an indicator of microbial biomass, reached the peak on day 6. Principal component analysis (PCA) of the PLFA compositions revealed that P. chrysosporium was well responsible for the succession of microbial community and showed that fungi were the predominant species at the end of the process. The correlation analysis between lignocellulose degrading ratio and PLFA profile in P. chrysosporium suggested that P. chrysosporium promoted lignin degrading as the main fungi with gram-positive bacteria.The lignocellulolytic microorganism, P. chrysosporium, was inoculated during different phases of agricultural waste composting and the effects on the diversity of microbial community and the enzyme activities were observed. The results of the present investigation revealed that inoculation during different phases had different effects on these parameters. (1) Three kinds of restriction enzymes, Alu I, Hae III and Taq I were used to analyse the change of microbial community diversity. The results showed that restriction enzyme Hae III was the most sensitive to the change of microbial community, restriction enzyme Alu I the second, and restriction enzyme Taq I the last. Restriction enzyme Taq I was not much suitable for analyzing composting samples. P. chrysosporium inoculated to composting system acted on certain microorganisms selectively and made them be the dominant species in order to promote the degradation of compost materials. However, the diversity of microorganism decreased after the first inoculation, the inoculation in the second fermentation was able to advance the effects of the inoculation in the first fermentation; (2) Inoculating P. Chrysosporium to composting did not induce much apparent changes on xylanase and CMCase activities. Whereas, P. Chrysosporium had significant stimulative effect on the secreting of MnP, LiP and certain prohibitive influence on the secreting of Lac when inoclated during the second fermentation phase.Three types of non-cultivate biology techniques, PLFA method, RFLP method and DGGE method were synthetically applicated to analyze changes of microbial community diversity during agricultural waste composting. The results showed that the three types of methods did not reveal the same relative similarities of composting samples based on PCA analysis of the biological characteristics entirely. (1) Data from PLFA profile showed discrete, it suggested each sample had its characteristic pattern, samples selected were representative. Microbial diversity of PLFA data was the highest among three types of methods. And data from PLFA profile was comprehensive to characterization of microbial community structure changes and more specific to characterization of microbial biomass changes. (2) Data from RFLP profile was more concentrated. The data also showed that bacteria community was instable at later stage during composting. And diversity of microbial community shown by RFLP method was lower; (3) Data from DGGE analysis showed that the succession of the microbial community included at least three different stages: mesophilic microbial community, thermophilic microbial community and maturation microbial community. The difference indicated that observing biological characteristics in composting with just one method should not be considered absolute, since the use of another method may lead to another interpretation of the relative composting similarities.Five strains of microorganisms were isolated from of agricultural waste composting. They were identified to be Bacillus subtilis, Pseudom onas aeruginosa, Aspergillusniger, Penicillium sim plicissim, and S treptom yces badius. To develop a high-efficient microbial inocula for composting, these strains of different ratios designed by orthogonal test L9 (34) were inoculated to natural rice straw during solid-state fermentation for 30 days. The strain mixture showed ligninolytic ability, which was further proved by enzyme secreting. When the ratio of bacteria:actinomycete:fungus was 85:5:10; B acillussubtilis:Pseudom onas aeruginosa, 55:25; and Aspergillus niger:Penicillium simplicissim, 2:1, the degradation rate of lignin, cellulose and hemicellulose was the highest, being 22.13%, 48.97% and 55.93%, respectively, after 30 day incubation. It was increased 19.16, 38.25 and 46.30 percent points, respectively, compared with the control. |
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