DETERMINATION OF MICROBIOLOGICAL QUALITY OF COMMERCIALLY PRODUCED BOTTLED WATER

Abstract

The research was conducted in different brands of commercial bottled water and local water sold in retail stores at Dinajpur districts of Bangladesh. The objective of this study was to assess the microbiological quality of water samples. For determination of microbiological quality of total viable count (TVC), total coliform count (TCC), total staphylococcal count (TSC), presence of gram positive and gram negative pathogenic bacteria were counted. Two brands of bottled water samples were collected from different retail stores of Dinajpur district . The bacteriological analyses were done at the Microbiology Laboratory Veterinary and animal science faculty, HSTU Dinajpur during the period from July to December — 2013.Total viable count (TVC) was performed according to the American Public Health Association , using plate count agar medium for TVC and Eosine methylene blue (EMB) agar media for total E. coli count and Staphylococcus agar no. 110 for total Staphylococcus count.The average TVC for Pran was 441x 10° CFU/ml (log 6.6), Jibon was 4.3 x 10° CFU/ml (log6.6) 4nd the TVC for these two brands were lower than the local water 4.7 x 10° CFU/ml (log 6.7). It was apparent from the present study that the bacterial load of water samples of the different brands were within the acceptable limit of public health safety, since the count was well below the acceptable limit.It was found that the highest extent of bacterial contamination and proliferation of viable bacteria occurred in loca Iwater. The average F. coli counts obtained from the study were in Pran, Jibon and Local water were 2.78x 10° CFU/ml (log 6.4), 2.63 x 10° CFU/ml (log6.4) and 2.42 x 10° CFU/ml (log 6.4) respectively . The presence of F. coli in local water was little bit high indicate the poor hygienic . The total staphylococcal count (TSC) per ml of water samples belonging to Pran, Jibon, and Local water varied from 2.2x10°( log 6.3), 2.4x10° (log 6.4) and2.6x10° (log 6.5) respectively.The results demonstrated that Jibon and Pran are of superior quality brands in respect of sanitary condition. Qualitative assessment of bottled water indicated that a good number of people preferred bottled water to tap water.