Cold-Tolerant Bacteria Screening and Its Inoculation in Composting at Low Temperatures

This study was conducted to screen cold-tolerant bacteria from different materials based on polymerase chain reactiondegeneration gradient gel electrophoresis( PCR-DGGE) combined with traditional plate culture. The biodegradability was also assessed after inoculation composting of chicken manure at low culture temperatures. 19 cold-adapted bacteria strains were isolated from low temperature compost samples. Dominant bacteria CY1( Psychrobacter sp.) was selected through a simple,high-throughput,PCR-based surveillance method( plate wash PCR). Mixed with CY14( Arthrobacter sp.),CY17( Bacillus sp.) and CY19( Paenibacillus sp.) in a mixture of cold-tolerant strains,it could efficiently degrade sugar,starch and protein at low temperature. In order to assess the biodegradability of the mixture of cold-tolerant strains,chicken manure composting with inoculation( T) was conducted at low temperature(4 ℃). Compared to the initial stage of composting,the concentration of organic matter(OM) decreased by 12. 64%. According to the three-dimensional excitation-emission matrix fluorescence spectra of dissolved organic matter( DOM),fluorescence intensity of Peak T(protein-like matter) in T decreased by 44. 10%,while that of Peak C(humic-like substances) increased by 39. 00% at the final stage of composting. The results indicated that the cold-tolerant strains could remain active at low temperature,and that initial startup of the composting system could proceed at cold regions of Northeast China.