Identification and characterization of bacteria from freshwater fish (Osteochilus hasseltii)

Abstract

Bacteria can cause many diseases to the organism and also can be as indicator to the pollution of environment such as freshwater. A very vast number of studied have been done to identify the types of pathogenic bacteria in freshwater fish but only a few studied were done to identify the types of bacteria that can be as a bioindicator to the water quality. Therefore, these studies were done to determine the water quality at Paya Sungai Udang by using bacteria from freshwater fish Osteochilus hasseltii. The samples of 0. hasseltii were collected from the polluted area in Paya Sungai Udang at Kuala Berang, Terengganu. These areas were polluted by a leachate from groundwater from the nearby landfill. The bacteria from this kind of freshwater species have been isolated and cultured on two types of agar which are Nutrient agar and MacConkey agar. All the isolated bacteria have been identified with morphology and physiology characteristics by using a few biochemical tests and Gram-stained. Biochemical test used in this study are Oxidase, Catalase, Methyl Red, Voges-Proskauer, SIM, TSI and Starch hydrolysis test. Results obtained from this study including 96 % of the isolates are from the Gram-negative group of bacteria and the rest 4 % are from the Gram-positive group of bacteria. Genus that already identified from the 0. hasseltii were Neisseria sp., Enterobacter sp., Serratia sp., Veil/one/la sp., Megasphaera sp., Pseudomonas sp. and Staphylococcus sp. Results obtained from this study indicated that area were polluted with some of the pathogenic bacteria that can be found in human and also can be concluded that the water at that area are polluted.