Study on some enteropathogens of street vended meat meals

Sixty random samples of street vended meat meals including 20 samples each of Shawerma, Liver sandwich and Hawawshi were randomly collected from different street vendors at Damanhur city Elbehaira Governorate for chemical and microbiological evaluation. The results revealed that, the mean values of total volatile nitrogen (TVB-N), Thiobarbituric acid (TBA) and Aerobic Plate count (APC) were 27.8±0.48, 25.8±0.17, 27.6±0.41 mg/100gm; 0.71±0.02, 4.2±0.33, 0.73±0.01mgMD/kg and 7.5x104±0.85x104, 4.8x104±0.50x104, 4.5x104±0.48 x104cfu/g in the examined samples of Shawerma, liver sandwich and Hawawshi, respectively. Also, enterococci, enteropathogenic E.coli, Salmonella and Shigella were isolated with an incidence of 25, 20, 25 %; 30, 20, 25 %; 10, 15, 0 % and 15, 10,10% from the examined samples of Shawerma, liver sandwich and Hawawshi, respectively. Serotyping of the obtained isolates of enteropathogenic E. coli revealed the detection of O157: H7, O128: K67, O86: K61, O26: K60 and O26: K72 strains at varying rates, Stereotyping Salmonella isolates revealed the detection of S. Enteritidis, S. Typhi and S. Paratyphi. In addition to, biochemical identification of the obtained Shigella isolates revealed the detection of S. dysenteriae, S. flexneri and S. sonnei. Two strain of isolated E.coliO157:H7 and one salmonella isolates were investigated by using PCR to detect presence of virulent genes stx1 (614 bp) and stx2 (779 bp) in E.coli O157:H7 and stn. Gene (617 bp) in Salmonella. From previously mentioned results, enteric pathogens still constitute common contaminants of street vended meat meals and their presence was very important due to its public health significance therefore strict hygienic measures must be applied to obtain safe and wholesome street vended meat meals.