Comparison of methods for microbial DNA extraction from swine feces and soil

The growth of the livestock industry resulted in the increase of feces and sullage, which caused considerable environment pollution. Swine feces would affect the soil microorganism when it entered the soil. To study the influence of swine feces on soil microorganisms, the same method for microbial DNA extraction from soil and swine feces was the basis. The efficiency of two methods as chemical lysis method and DNA Isolation Kit method for microbial DNA extraction was compared in this experiment. The results show that microbial DNA from swine feces can be extracted by two methods. But microbial DNA of soil can’t be extracted by the DNA Isolation Kit method. Microbial DNA extracted from swine feces can be used for PCR amplification，but the amplification result is not steady. Microbial DNA from soil is high in yield and low in purity when the chemical lysis method is used. By contraries, microbial DNA from swine feces is low in yield and high in purity. It shows that microbial DNA extracted from swine feces is more suitable for PCR amplification than from soil. After purification the extracted DNA samples from swine feces can be used for PCR amplification, using primers of the bacterial 16SrDNA gene, but not be the extracted DNA samples from soil. In conclusion, the chemical lysis method for microbial DNA extracted from swine feces is feasible. But the better method for microbial DNA extracted from soil is needed to be studied.