ISOLATION AND IDENTIFICATION OF PATHOGENIC BACTERIA PRESENT IN COMMERCIALLY IMPORTANT FISH, SHELLFISH, WATER AND SOIL SAMPLES OF KAPTAI LAKE

Abstract

Organisms that cause human infections are transmitted from fish or the aquatic environment is quite common. To analyze the bacterial population (pathogenic) of fish, soil and water from Kaptai Lake, this study aims to isolate enteric pathogenic bacteria from fish, soil and water that might be transmitted to humans after handling and consumption of these. To determine the presence of E. coli, Salmonella, Shigella, V. cholera, V. parahaemolyticus, V. vulnificus from fish, soil and water and to isolate those bacteria, different kinds’ agar like EMB agar, Xylose Lysine Deoxycholate (XLD) Agar and TSI agar were used in this study. To determine the bacterial load Total Plate Count method was used. Result showed that, among 20 fish species the highest and lowest amount of bacterial load was found in Puntius ticto (8.53±0.21×106 CFU mL-1) and Microbrachium rosenbergii (2.45±0.25 ×104 CFU mL-1). Moreover, in case of soil (6.13±0.66×106 CFU mL-1) and water (3.90±0.20×106 CFUmL-1) highest bacterial load was found in station-12. Due to the presence of E coli in most of the water and soil of most of the sampling sites, it can be concluded that, these sites may be contaminated by human manure. Besides this, as sampling sites at Baghaichhari area was highly contaminated with pathogenic enteric bacteria which suggest reducing human interference in this area.