Isolation and identification of bacteria from marine market fish Scomberomorus guttatus (Bloch and Schneider, 1801) from Madurai district, Tamil Nadu, India
Abstract The present study was conducted to evaluate the hygienic quality and freshness of fish Indo-pacific King Mackerel “Scomberomorus guttatus” through the investigation of the occurrence of bacteria which is an indicator for fish quality. Fishes were collected every fortnight from Madurai fish market on monthly twice of January 2014 to March 2014. Skin surface of the fish was examined. Escherichia coli, Proteus vulgaris, Bacillus subtilis, Klebsiella pneumonia, Pseudomonas aeruginosa and Staphylococcus aureus were identified by Biochemical tests (IMViC Tests). Among the six bacterial species E. coli and K. pneumonia were found in all the collected samples where as other bacterial species were not found. The result of this study revealed that raw fish sold in Madurai fish market has high contamination so the presence of the bacterial species has strongly suggested the urgent need to improve the quality control systems in Madurai fish market.
Comparative studies and microbial risk assessment of different Ready-to-Eat (RTE) frozen sea-foods processed in Ijora-olopa, Lagos State, Nigeria
This study reports the comparative studies and microbial risk assessment of different frozen seasfoods processed in Ijora-olopa, Lagos State, Nigeria. Different varieties of popularly consumed frozen sea-foods bought from different processing shops in Ijora-olopa, Lagos were microbiologically analyzed for the presence of microorganisms. Total plate counts, enterobacteriaceae counts and Salmonella-Shigella (SS) counts were enumerated using Plate Count Agar (PCA), Eosin Methylene Blue (EMB) Agar and Salmonella-Shigella Agar (SSA), respectively. The total counts for all the processed frozen seafood products ranged between 1.08 x 102 to 2.86 x 104 CFU/ml. These were generally high exceeding the limit of 1.0 x 102 CFU/ml. The coliform count ranged between 0.76 x 102 and 1.36 x 104 cells. The Salmonella-Shigella (SS) count ranged between 0.26 x 102 and 0.96 x 104 cells. Seventeen (17) isolates were characterized from the samples on PCA with percentage of occurrence of different microorganisms characterized as follows: Bacillus cereus (29.4%), Enterobacter aerogenes (29.4%), Salmonella sp. (17.6%), Flavobacterium sp. (11.8%), Micrococcus sp. (5.9%), and Staphylococcus auerus (5.9%). Consumption of some of this water and the seafood product processed with these water samples available in the market should be discouraged.
[Bacteriological evaluation of fresh tilapia (Oreochromis niloticus) coming from the northern region of Costa Rica].
The following work presents an evaluation of the normal and pathogenic flora associated to tilapia (Oreochromis niloticus), since there are no previous national studies referred to the microbiological quality of this product. The total aerobic plate count, lactic bacteria, Enterococcus sp and Aeromonas sp and fecal and total coliform count, and the presence of Listeria sp and Salmonella spp from the external surface of tilapias were evaluated. A total of 50 samples, coming from San Carlos and Cañas zones were transported in ice to the Food and Water Microbiology Laboratory, Universidad de Costa Rica, where the laboratory analysis were performed, according to the methodology presented by de American Public Health Association, 1998. The results obtained confirm the microbiological freshness of the product when the analysis was performed, although coliform levels were unacceptable. Listeria sp was not found, but the isolation of Salmonella spp. confirms the fecal contamination of water where the tilapia is grown, aside of the Public Health concern. Also, it was found a high number of Aeromonas sp, as part of its normal flora, so we recommend including this genus in the quality standards for fresh fish. According to the data obtained, there was no significant difference (95% confidence) between the total plate count, fecal and total coliforms, Enterococcus sp. and Aeromonas sp. from the samples coming from the zones of San Carlos and Cañas.