*Corresponding author. Email: tun.nur@yahoo.com eISSN: 2550-2166 / © 2019 The Authors. Published by Rynnye Lyan Resources Food Research 4 (1) : 161 - 165 (February 2020) Journal homepage: http://www.myfoodresearch.com FULL PAPER Comparative microbiological analysis of four different sea fishes collected from local market in Dhaka Metropolis 1, *Nur, I.T., 2 Mou, A.N. and 1 Habiba, U. 1 Department of Microbiology, Stamford University Bangladesh, 51 Siddeswari Road, Dhaka-1217, Bangladesh 2 Biotechnology and Genetic Engineering Discipline, Khulna University, Khulna 9208, Bangladesh Article history: Received: 14 July 2019 Received in revised form: 5 August 2019 Accepted: 14 August 2019 Available Online: 6 September 2019 Keywords: Raw fish, Cooked fish, Frozen cooked fish, Pathogens, Microbiological quality DOI: https://doi.org/10.26656/fr.2017.4(1).253 Abstract The present investigation attempted to evaluate the existence and survival of spoilage microorganisms in four common sea fishes (Poma, Rupchanda, Koral and Tuna) available in Bangladesh and to determine the effects of cooking temperature to optimize the growth of fish microflora. Moreover, the status of fish in frozen condition after cooking was also studied. A total 4 categories of sea fishes were collected from the local shops in Dhaka city. Raw, cooked and frozen fish samples were analyzed for the existence of pathogenic bacteria through the conventional cultural techniques and the confirmative biochemical identification procedures. Total viable bacteria were present in all four fish samples in raw, cooked and frozen condition up to 6 log CFU/mL. Most of the raw fish samples were found to harbor a huge population of microorganisms up to 5 log CFU/mL including the fecal coliforms. Several specific bacterial species like E. coli, Klebsiella spp., Salmonella spp., Shigella spp., Staphylococcus spp., Pseudomonas spp. and Vibrio spp. were present in raw samples. However, the microbial load reduced from the fish after cooking and the status was static in frozen condition. Thus, the incidence of fecal coliforms in raw fish may be considered as a serious threat to the public health upon consumption of such fishes. 1. Introduction Fish and fish products are important source of animal protein, highly unsaturated fatty acid (HUFA) and polyunsaturated fatty acid (PUFA), minerals and vitamin. Marine fish oil is a good source of omega-3 fatty acids (Huynh et al., 2007; Dhaneesh et al., 2012; Belton et al., 2014). In Bangladesh, about 60% of the total animal protein intake is obtained from fishery products (Bogarda et al., 2015; Eizenberga et al., 2015). Marine water of Bangladesh also has 442 species of fish and 36species of marine shrimps and which is widely consumed by Bangladeshi people and tourists (Quader, 2010). Because of its high nutritive value, sea fishes are a major vehicle for pathogenic bacteria. Fishes can be contaminated by both aquatic environment and post- harvesting condition (Al-Sheraa, 2018). Due to the attack of pathogenic bacteria and fungi a wide ranges of sea fishes spoilages occurs which adversely affect the economic condition in Bangladesh and as well as public health. Contamination of sea fishes can take places at several stages of transport, handling, processing, packaging and storage condition by both bacteria and fungi. It was reported that Processing materials, water and ice could be a source of contamination (Sanjee and Karim, 2016). However, normal flora of fish proceeds spoilage due to inappropriate packaging (Bryan, 1980; Okonko et al., 2008; Okonko et al., 2009). Aeromonas, Vibrio spp., Pseudomonas spp., Staphylococcus spp., Salmonella spp., Listeria spp., Clostridium perfringens. are mainly caused various foodborne illness when they enter our intestine through contaminated sea fishes (Feldhusen, 2000; Vazquez-sanchez et al, 2012; Zarei et al., 2012; Falaise et al., 2016; Iwamoto et al., 2000). Along with bacteria and fungi, seafood-associated illness occurring by viruses (Norovirus and Hepatitis A) and certain parasites. Most outbreaks of food poisoning associated with fish and seafood derive from the consumption of raw or insufficiently heat treatment, insufficient cooking and cross-contamination during processing (Mohammed et al., 2017). Raw fishes naturally have a number of bacteria, and this can be opportunistic and causing foodborne infections rapidly if it is left for several hours at room temperature without processing. Pathogenic bacteria