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Prevalence and Characterization of Escherichia coli in Raw Milk and Some Dairy Products at Mansoura City
2022
Amira H.M. Ibrahim | Mohammed E.E. Ali | Marwa F.E. Ahmed | Adel Abdelkhalek
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.
Mostrar más [+] Menos [-]Virulence Genes and Antibiotic Resistance Patterns of Bacillus cereus Isolated from Egyptian Milk, Milk Powder, and Ice Cream
2023
Heba A. Dowidar | Amira H. El-Baz
One of the most common food poisoning illnesses globally is caused by Bacillus cereus, which causes emetic and diarrheal food poisoning. Forty–two (42%) out of 100 samples from raw milk, powdered milk, ice cream, and pasteurized milk were positive for B. cereus, with a high prevalence in raw milk at 64%. Three virulence genes (nheA, cytK, and hblC genes) were characterized among 42 B. cereus isolates with variable frequencies. Detection of the nheA gene showed a high level of 90.4%, followed by the cytK gene in percentage at 50%, and the hblC gene at 47.6%. All examined strains were resistant to Penicillin, Oxacillin, then Cefixime and Ampicillin (85.7%), followed by Nalidixic acid (73.8%), Sulphamethoxazol-Trimethoprim(61.9%), and Oxytetracycline and Cephalotin (52.3%) whilst sensitive to Gentamicin (75%), followed by Enrofloxacin and Erythromycin (50%). Unfortunately, all examined strains are MDR and show 23 resistance patterns, this represents a real health malice for the people of Egypt. The obtained results demonstrated the rise of pathogenic B. cereus, a virulent organism that is multidrug-resistant, in Egypt's retail milk and milk products.
Mostrar más [+] Menos [-]Effect of Probiotics and Natural Extracts on Hygienic Quality of Some Dairy Products
2023
Sally S. Fathy | Esmat I. Awad | Salah F.A. Abd-El Aal | Eman N. Abdelfatah | Asmaa B.M.B. Tahoun
Dairy products are responsible of contamination with multiple microorganisms by different ways during handling, processing, and production, thus it would be unfit for consumption and form a public health hazard. Food borne diseases become a great trouble containing an extensive range of disorders caused by viral, bacterial, parasitic, or even chemical contamination of food. That reflected a problem due to the massive use of traditional antibiotics in human and animal diseases treatment and from this time, the persisted development of new programs of antimicrobial agents has become of rising importance to medicine. Probiotics not only used in treating gastrointestinal disease, but also used in food industry as natural antimicrobial substances which have a lot of bacteriostatic or bactericidal effect against different food borne pathogens. Contamination by foodborne pathogen in foods represents a serious challenge that may lead to severe disorders as toxic infection, food poisoning and intoxication. These pathogens caused illness, mortality and product withdraws. In fact, attention the using of herbal products has increased during the recent decades. Plants play an significant role in human health, it is likely that 25% of modern medicine were originated directly or indirectly from herbs. Many compounds present in plants have been reported to be antimicrobial, allopathic antioxidants, biologically active and have bioregulatory properties that have been proven real anti-bacterial, insecticidal, antifungal, antiparasitic, anti-viral and antioxidants. Aromatic essential oils are used as flavouring and prevent the growth of microbial contaminants and mould in food industry. Recently, probiotic bacteria have been used as substitutes for antibiotics to treat or different prevent intestinal infections. Studies of using natural preservatives either alone or in combination with other alternative have been verified (as probiotic) not only to evaluate synergism but also to produce effective combinations. Finally, we will discuss the effect of probiotic and natural extract on hygienic quality of some dairy products.
Mostrar más [+] Menos [-]Antiquorum Sensing and Antibiofilm Activities of Natural Products Against Bacillus cereus.
2023
Ahmed M. Ammar | Ahlam A. Gharib | Norhan K. Abd El-Aziz | Rana Mohamed Mahmoud
Bacillus cereus (B. cereus) is a Gram-positive, spore-forming, and facultative anaerobic bacterium that is widely distributed in the environment. Commonly, B. cereus is a soil occupant and is generally isolated from food and food products. It is a human pathogen that causes two variant types of gastrointestinal diseases: diarrheal and emetic. Diseases caused by multidrug-resistant (MDR) bacteria are difficult to be treated. In addition, group of B. cereus has several virulence factors, which play their roles in pathogenesis, infectivity and its capability to form biofilms. B. cereus biofilm is grown on medical devices either abiotic or biotic surfaces. This biofilm avoids the bacteria from the effect of antibiotics and host immune system leading to chronic infections, persistence and mortalities. Thus, it is necessary to explore new antiquorum and antibiofilm agents better than the conventional therapy to eliminate the biofilm that reflect on controlling B. cereus infections. The present review will discuss B. cereus virulence attributes, antibiotic resistance profiles, and their ability to produce biofilm as well as its molecular regulation. The application of the antiquorum and antibiofilm approaches for infection control will be illustrated as well. Finally, we will spot the light on their consequence in food industry loses and human health risk.
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