Biochemical Identification of Bacteria in the Polluted Water Fish

Abstract

The bacteria are the most common naturally occurring organisms in an aquatic medium which are important for the degradation of the aquatic wastes, chemical substances and pollutants.. The normal bacteria of the fish is the flora of the medium in which they live. The heavy mortality that occurs in the cultured and the feral fish population is commonly caused by the bacterial diseases and affects fish living in the polluted waters. Therefore, the present study was aimed at studying the bacteria which can be easily identified by using biochemical parameters. During the present study bacteria of fish collected from the polluted water body was identified using various biochemical tests and compared with that of the fish from normal or comparatively less polluted water body .The polluted water fish are more prone to the bacterial ,fungal ,viral and parasitic infections than the fish living in the less contaminated waters. Therefore, a comparative study involving fish bacterial catalase ,peroxidase, and oxidase activities was qualitatively detected from fish obtained from both the normal water body and the polluted water body . The catalase activity was interpreted as positive for example Staphylococcus species and allied ones and negative for the streptococcus and related species. Peroxidase also showed similar results. The oxidase activity was found to be less than the other two enzyme activities. The difference in the enzyme activities are due to the differential breakdown of the pollutants by the bacteria present over the surface of the body of the fish and in the body fluids and more so in case of oxidase enzyme due to the low levels of oxygen as observed in the present study.