Abstract
For the analysis of microbial population in activated sludge samples, significant cost and time are spent for the extraction of DNA from cells. In the present study, DNA was first extracted from samples by sonication, and the crude extract was subjected to PCR (polymerase chain reaction). When the sonicated sample was diluted to around 1, 000 to 10, 000 times, PCR products were obtained. For the same sample, DNA was extracted by the present method and one of the commersial DNA extraction-purification kits using beads beating, and was subjected to T-RFLP (Terminal-Restriction Fragment Length Polymorphism) analysis targetted at a partial sequence of 16SrRNA gene. While the obtained fragment patterns had differences, it was found the present method can be applicable for at least some part of bacteria. It is worth to improve the present method by further research and development, as it is extremely simple.
