Development of a Method for the Total Count of Marine Bacteria on Algae

In an initial attempt to develop a technique for the enumeration of bacteria on littoral algae, the authors observed that homogenization of the algal samples in the Waring Blendor resulted in the death of the marine bacteria contained in the samples. Further work on this lethal effect of blending showed that two detrimental factors, heat and mechanical injury of the cells, were implicated. These factors were due to the increase in temperature during homogenization and the high speed of rotation of the knife-blade assembly of the Waring Blendor. From these findings, a satisfactory technique was formulated for obtaining homogenates of marine materials for the total count of bacteria. This involved homogenization at speeds of about 5000 r.p.m. (using a Servall Omni-Mixer homogenizer) and a temperature of homogenization not exceeding 30 °C.