Comparative microbiological analysis of raw fishes and sun-dried fishes collected from the Kawran bazaar in Dhaka city, Bangladesh

I.T. Nur,B. Ghosh,M. Acharjee

doi:10.26656/fr.2017.4(3).368

Abstract

Along with the raw fishes, dry fishes also have a huge contribution to meet up the demand of protein in our daily meal. The assay of microbiological quality is therefore needed to ensure the public health safety. The present study was emphasized on the existence of pathogenic bacteria in raw and dry fish. A total of 50 samples of raw fishes and sun-dried fishes was accumulated aseptically for microbiological quality analysis. Isolation of bacteria was done by spread plate method. All the samples including both (raw and dry) fishes harbored bacteria and fungi up to 106 CFU/g. E. coli was found in all samples as a specific pathogen. In case of raw fishes total viable count (TVC) and total coliform count (E. coli) were recorded up to 2.5x106 CFU/g and 5.2 x104 CFU/g respectively whereas a significant load of Salmonella spp. was observed in almost all samples. Staphylococcus spp. and Pseudomonas spp. were present up to 5 x102 CFU/g and 1.8 x 102 CFU/g respectively. Likewise, total viable count (TVC), total coliform count (E. coli) and fungal load were recorded in dry fish up 3.50 x 105 CFU/g, 1.2 x103 CFU/g respectively. Fungal growth was observed in all experimental raw and dried fishes. For most of the pathogenic isolates, higher rates of resistance were found against Ceftriaxone, Penicillin, Nalidixic acid, Neomycin. On the other hand, most of the isolates were found to retain higher sensitivity against Imipenem, Ciprofloxacin, Tetracyclin and Amoxicillin. This data suggested that the dry fish harbored fewer bacteria than raw fish and sun drying method is still a useful technique for the preservation of fish.

Highlights

IntroductionFishes play an important role in human diets as good sources of animal protein that provide other important elements necessary for the maintenance of healthy bodies (Dewi et al, 2011; Ravichandran et al, 2012)
One of the major factors contributing to poor quality of the fish in retail trade is unhygienic handling, improper storage, physical damage and come to contact in dirty water and microorganisms
Our present study revealed that both raw fish and sun -dried fish may nurture various pathogenic microorganisms

Summary

Introduction

Fishes play an important role in human diets as good sources of animal protein that provide other important elements necessary for the maintenance of healthy bodies (Dewi et al, 2011; Ravichandran et al, 2012). Due to the attack of pathogenic bacteria and fungi a wide range of fish spoilage occurs which adversely affect the economic condition in Bangladesh and as well as the public health safety (Khan and Khan, 2001; Musa et al, 2010; Dewi et al, 2011). In tropical countries like Bangladesh, fish drying is a prime and inexpensive preservation method (Balachandran, 2001). In Bangladesh point of view, the fish drying process is widely performed by the community of the coastal region (Balachandran, 2001). Traditional drying methods cannot be applied during the monsoon because of the high humidity. By this time, the fish can absorb the moisture and microbial population such as bacteria, fungi and even viruses

Methods

Results

Conclusion