Media for the Isolation of Aerobic and Facultatively Anaerobic Bacteria in Freshwater Environments

Abstract

Six culture media including 2 general and 4 selective agar media were examined to select the media for the investigation of aerobic microflora in aquatic environments. As criteria for the selection, the number of developed colonies, genus diversity of grown bacteria and viable counts of each genus on each medium was adopted using water, sediment and organism samples taken from the Tama River. In the course of this study it was found that (1) the composition of medium influenced not only viable counts but also generic composition of the bacteria grown on it; (2) A medium with lower nutrient (1/20 PYBGF agar) supported a vareity of bacteria with high population densities; (3) viable counts of each genus varied with the composition of media; (4) Many kinds of bacteria other than the target organisms were recovered on a selective medium. It is thus suggested from the above results that the combination of 1/20 PYBGF, PYBGF, MacConkey and PEA agars is suitable to isolate and investigate the aerobic microflora in freshwater environments. © 1983, The Japanese Society of Fisheries Science. All rights reserved.