![]() | Only 14 pages are availabe for public view |
Abstract Since molluscan shellfish are subject to the risk of contamination with various pathogens either during their presence in their aquatic environments or after being harvested for marketing. Ninety random samples of Gandoufly, Om El-Kholoul and squid (30 each) were collected from different retail markets of Alexandria Govemorate. The samples were transferred directly in an ice box to laboratory where they were subjected to microbiological examinations. The examinations revealed that the mean values of total halophilic bacteria in Gandoufly, Om El-Kholoul and squid samples were 6.1 x104 ± 1.2 x 102, 2.8 x l0 ± 7.4 io and 6.8 x l0 ± 9 x lO3cfiuJg respectively. All examined samples barbered halophilic bacteria (100% incidence). 46.7%, 33.3% and 76.7% of the examined molluscs samples have total halophilic count range between I o4 — I 05/gin, respectively. The incidence of halophilic mould in Gandoufly, Om E1-Kholoul and squid samples was 60%, 76.7% and 66.7% with mean value of 2.4 X 10 ± 7,2.5 x 10 ± 4 and 7.7 x 10 ± 1.3 x 10, respectively. Also the incidence of halophilic yeast was 56.7%. 60% and 100% with mean values of 1.57 x 102 ± 7.6 x 10, 1.1 x 102 ± 2.2 x 10 and 1.88 x 102 ± 2 x 10, respectively. All examined molluscan samples (100%) were positive for coliforiTis with mean values of 1.8 x 102± 6.1 x 10, 1.1 x l0± 4.2 x 102 and 1.03 x 102± 2.7 x 10, respectively. Vibrio parahaemolyticus was isolated from Gandoufly, Om E1-Kholoul and squid samples at an incidence of 30, 23.3 and 10%. While the incidence of each of Staphylococcus aureus was 43.3%, 63.3% and 36.7%, the faecal coleform was 33.3, 56.76 and 13.3% and E.coli was 26.7, 40 and 10%, respectively. Salmonella’ could not he isolated from any examined sample. In the experimental section of this work the effect of some organic acids (citric and acetic) on total halophilic bacteria and coflform count in Om El-Kholoul was investigated. The concentration of both acids was 5%. The Om E1-Kholoul sample was dipped in each acid for 1, 5 and 10 minutes. The result revealed reduction of both halophilic and colifonTi counts in the examined samples, but the acetic acid had more bactericidal effect than citric acid, and this effect is directly proportional to time of dipping. The different sources of contamination, measures suggested to prevent or minimize such contamination, as well as the hygienic and public health significance of isolated microorganisms have been discussed. |