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Bacterial contamination of fermented dairy products has serious implications for both safeties of the final products, and the transmission of foodborne pathogens to the consumers. In this regard, 175 samples of fermented dairy products including 50 each of plain yoghurt, fruit yoghurt, laban rayeb, and 25 from mish cheese were randomly collected from different supermarkets and retail shops in Dakahlia Governorate, Egypt. Samples were examined bacteriologically for the prevalence of Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), particularly, E. coli O157. The recovered isolates were examined for the detection of toxin, and virulence-associated genes using PCR. The obtained results showed that the average counts (CFU/g) of total bacterial, psychrotrophic, coliform, and S. aureus were 1.72x105, 9.9 x103, 5.08x102, and 3.07 x102 for the plain yoghurt, 7.1 x 104, 2.3 x 103, 9.5 x10, and 3.3 x10 for fruit yoghurt, 6.07x104, 6.1 x 103, 9.8 x10, and 1.35x102 for laban rayeb, and 1.2 x 106, 2.5 x104, 8.3 x10, and 7.2 x103 for Mish cheese, respectively. E. coli and E. coli O157 were detected in 13 out of 175 (7.43%) and 4 out of 175 (2.3%) samples, respectively. Using PCR for 9 selected E. coli isolates showed that 7 out of 9 E. coli isolates were positive for the stx1 gene, 5 out of 9 were positive for stx2, and 3 out of 9 were positive for eaeA, and 4 out of 9 were positive for hylA. S. aureus showed that 55.6% of the recovered isolates were coagulase positive. Ten randomly selected S. aureus isolates tested positive for nuc (thermonuclease genes), while mecA (methicillin-resistant S. aureus "MRSA") gene was detected in 20% of the examined isolates. Therefore, strict hygienic measures should be adopted during all steps of the manufacture of such dairy products. [ABSTRACT FROM AUTHOR]

The present study aimed to detect the prevalence and antibiotic sensitivity pattern of Escherichia coli in raw milk and some dairy products (white soft cheese, yoghurt, and Laban rayeb) in Mansoura city, Egypt. A total of 200 samples, obtained equally from raw milk (farm and market milk), white soft cheese (Kareish and Domiati), yoghurt (small scale and large scale), and Laban rayeb (small scale and large scale) were examined for the presence of E. coli by using eosin methylene blue agar (EMB). Suspected E. coli isolates were confirmed by biochemical tests and then selected numbers of E. coli strains were identified serologically. Furthermore, serologically identified strains were subjected to antibiotic sensitivity testing. In total, the prevalence of E. coli recovered from the examined raw milk and dairy products samples was 28% (56/200). The highest prevalence was detected in raw market milk (52%), followed by Kareish cheese (48%) while, the lowest prevalence was obtained in large-scale yoghurt and large-scale Laban rayeb samples (8%). The selected numbers of E. coli strains subjected to serologic examination showed variable somatic and H antigens. About 58.8% of E. coli strains showed multi-antibiotic resistance (MAR) criteria at least to one antimicrobial in three different classes of antibiotics. The highest resistance was obtained from erythromycin (100%) then oxacillin (94%), cefepime (82%), penicillin G (76.5%), and ampicillin (58.5%), nalidixic acid (52.9%) and cefazolin (47.1%). the obtained results show the great hazard proposed to public health, therefore, the application of hygienic measures in all practices concerning dairy industry from farm to fork is not just advice but a necessity to maintain human health. [ABSTRACT FROM AUTHOR]

Objective: This work investigated the antimicrobial resistance (AMR) and virulence of Escherichia coli and Staphylococcus aureus in communally consumed cheeses in Egypt. Materials and Methods: This study examined 100 samples of Domiati, Tallaga, Cheddar, and Ras cheese collected from several shops and supermarkets. Samples were spread on selective media to isolate bacterial strains. Molecular characterization of bacterial isolates was carried out using polymerase chain reaction to determine Shiga toxin 1 (stx1), Shiga toxin 2 (stx2), eaeA, and nuc genes. The isolates were tested for susceptibility to 14 antibiotics by disk diffusion assay. Results: In this study, several E. coli serotypes were identified. E. coli O26:H11, O103:H2, and O111:H2 expressed stx1/2, E. coli O114:H4 expressed stx1, E. coli O17:H18, O21:H7 and O146:H21 expressed stx2, while only E. coli O26:H11 and O111:H2 expressed eaeA. The E. coli isolates were resistant to at least one antibiotic, while most isolates (82.4%) showed multidrug resistance (MDR). AMR to erythromycin was the highest (100%), followed by nalidixic acid (94.1%), cefotaxime (82.4%), vancomycin and cephalothin (64.7%), penicillin G (52.9%), sulfamethoxazole (47.1%), amikacin and kanamycin (35.3%), ampicillin (29.4%), tetracycline and ciprofloxacin (23.5%), and doxycycline (11.8%), while gentamicin showed the least resistance (5.9%). The multiple antibiotic resistance (MAR) index of the isolated E. coli ranged from 0.071 to 1 (mean = 0.478). All S. aureus isolates expressed the nuc gene and demonstrated resistance to at least one antibiotic, and 90% of isolates were MDR. AMR to kanamycin and cephalothin was the highest (100%), followed by penicillin (90%), doxycycline (70%), nalidixic acid and sulfamethoxazole (60%), erythromycin (50%), tetracycline, cefotaxime, and gentamicin (40%), ciprofloxacin and ampicillin (30%), and amikacin (20%). In comparison, vancomycin showed the least resistance (10%). MAR index of isolated S. aureus ranged from 0.143 to 1 (mean = 0.529). Conclusion: The antimicrobial-resistant E. coli and S. aureus are potential risks for public health and may have a role in disseminating AMR to other pathogenic and non-pathogenic microbes. [ABSTRACT FROM AUTHOR]

Objectives: This study was designed to assess the contamination of enterovirulent Escherichia coli with table eggs at Mansoura, Egypt. Materials and methods: A total of 100 commercially available table eggs were randomly collected from various groceries and supermarkets at Mansoura, Egypt. The samples were screened for the presence of E. coli through conventional bacteriological and biochemical analyses followed by confirmation by polymerase chain reaction. Results: Overall, 18% (n=18/100) samples were found to be contaminated with one or more E. coli isolates. All possible E. coli colonies (n=52) appeared on MacConkey agar plates during the screening process were picked for further analysis. Among the 52 suspected isolates, 24 were confirmed as E. coli, which were further serotyped using polyvalent E. coli antisera. In this study, 9 different E. coli serotypes namely O78, O114, O2, O44, O1, O125, O128, O124 and O26 were identified. Out of these 9 serological strains, 5 (O78, O2, O44, O125, O124 and O26) were positive for eae gene, and 3 (O44, O1 and O128) were positive for stx2 gene. Two serological strains (O44 and O1) were positive for both stx1 and eae genes, while O125 and O114 were positive for stx2 and eae genes. Two strains (O78 and O128) were found to be positive for all three genes (stx1, stx2 and eae). Conclusion: Ensuring hygienic measures can effectively reduce the microbial load from table eggs. [ABSTRACT FROM AUTHOR]

The quality of UHT milk is highly influenced by the microbiological characteristics of raw milk and the heat treatment applied. The current study aimed to check whether selected UHT milk brands meet the minimum legal Egyptian standard that is represented in their label manuscript to introduce it in complete nutritive values and hygienic state to resident patients in Mansoura University Hospital (MUH). A total of 80 UHT milk samples from four different brands (A, B, C, and D, 20 of each) were collected from MUH and directed to the physicochemical and microbiological evaluation. MCCW lactoscan® revealed that 100% of all brands were incompatible with the legal SNF% requirements and only brand A was compatible with all other legal standard requirements. The physicochemical investigation showed a significant increase in fat (P < 0.05), protein, TS, SNF, ash, density, and freezing point (P < 0.01) in A milk brand compared with the other three brands. Total bacterial count (CFU/mL) exceeded the legal standard in 10% of B, 10% of C, and 15% of D brands. Total coliform count (CFU/mL) was incompatible with the legal standards in 15% of B, 25% of C, and 40% of D brands. E.coli and Salmonella spp. were negative in all investigated brands. Pseudomonas was identified in 75% of B, 60% of C, and 75% of D brands. Klebsiella was detected in 25% of B, 40% of C, and 25% of D brands. Our findings indicate that there are somewhat inferior quality and potential risk hazards of consuming B, C, and D UHT milk brands. [ABSTRACT FROM AUTHOR]