Thus, DEPC was washed from the deposits. About 300 micro liters of the final deposits were transferred to a microtube 1.5 and finally about 50 micro liters of the final deposit was transferred as a bacterial mass to a microtube 1.5, after it was centrifuged at 14 000 r/min for 2 min and at the next stage, it was analyzed by PCR test. Moreover, a number of samples were comparatively tested with or without DEPC to evaluate the necessity of its application.