| Composting takes the advantage of natural microorganisms, under the manual control condition, it is a process which will transform biodegradable organic to fertilizer. However, the microbes can be cultured, only 1% to 10% of the microbes from natural habitats, so it can't well reflect the microbial diversity in the natural environment of the original state. With the development of molecular biology and phylogenetic analysis, based on 16SrDNA gene molecular biology methods are gradually being used to analyze complex ecosystems. In this paper, composting used polymerase chain reaction - denaturing gradient gel electrophoresis (PCR-DGGE) technology to study the relationship between colonies and lignocellulose degradation during the composting process.Lyticase lysis, ultrasonic lysis and grinding lysis in liquid nitrogen with CTAB as genomic DNA extraction methods for bacteria and fungi were studied to analyze the diversity and succession of the microbes during solid-state fermentation. Quantity and purity of DNA were measured by ultraviolet spectrophotometer. PCR amplification was carried out with a eubacterial 16S rDNA targeted primer pair (341F and 907R) and a fungi 18S rDNA targeted primer pair (NU-SSU-0817 and NU-SSU-1196). The bacterial and fungal diversity during solid-state fermentation was analyzed by denaturing gradient gel electrophoresis (DGGE). The results showed that the rude and purified DNA fragments extracted during solid-state fermentation have a length of about 23 kb. The length of DNA fragments after bacterial and fungal PCR amplification is about 586 bp and 422 bp, respectively. DNA band profiles by DGGE analysis for either bacterial or fungal PCR products testify the similar microbial diversity for three DNA extract methods. The results by the ultraviolet spectrophotometer showed that lyticase lysis yielded the highest quantity of DNA, ultrasonic lysis followed and grinding lysis in liquid nitrogen with CTAB produced the lowest quantity of DNA. Therefor, Lyticase lysis was best.According to the screening method of DNA extraction, we choosed lyticase lysis by which the total DNA of the organic solid waste composting microorganisms was extracted. After purification, the total DNA was amplified with PCR using the GC-341F/907R primers to obtain the 16S rDNA genes. The PCR amplified products were separated and identified by DGGE,which could show the information of organic solid waste composting microorganisms. It showed that there was more microbial diversities in the initial stage of composting. Some mesothermal microorganisms were eliminated with the rising of the temperature, and the microbial diversities of high temperature stage decreased. The thermophilic bacterias emergence became to the preponderant microorganisms. After the high temperature stage, the diversity of microorganisms still dereased. The temperature of the composting was an important factor effecting the microorganisms of the pile. And the pile might have different preponderant microorganisms in different temperature. At the same time, several characteristics of composting parameters were measured. After 39 days compost, the results showed that the product of compost met the basic requirements. Measurement of the lignocellulose degradation as well as the enzyme activity of Lac, Lip, Mnp showed that when microbial populations increased, cellulose, hemicellulose degradation rate and volume of activity also increased. When the number of microbial decreased, the rate of lignocellulose degradation and enzyme activity would slow. So we could see that the number of microbial populations and lignocellulose degradation have a certain relationship.In conclusion, Lyticase lysis which was used to study diversity and succession of the microbes and the relationship between communities and biodegradation was feasible. These methods would be helpful for solving the problem of subjectivity about strains selecting, they could provide useful information for the researching of the environment systematic communities.
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