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Effect of Antibacterial Activity of Zinc Oxide Nanoparticles against E. coli and Staph. aureus on Quality and Shelf Life of Minced Meat
2023
Mohamed S.M. El Asuoty | Fayza A.I. El Tedawy | Nasser M.M. Abou-Arab
Metal nanoparticles have attracted a lot of attention recently in several nanotechnology fields. Zinc oxide nanoparticles (ZnO NPs) have attracted the most interest among metal nanoparticles due to their possible antibacterial impact, particularly in regulating the safety of meat and meat products. This study looked at how the quality and shelf life of minced beef were affected by antibacterial activity of zinc oxide nanoparticles (ZnO NPs) against S. aureus and E. coli. So, minced meat samples were inoculated with S. aureus and E. coli and then exposed to various doses of ZnO bulk and nanoparticles, including 4 mM, 6 mM, and 8 mM then kept at 4 °C for 12 days, then E. coli and S. aureus growth and count were examined to assess ZnONPs action on them and on minced meat quality and shelf life. The findings showed that E. coli and S. aureus growth and count in minced beef were significantly reduced by ZnO NPs at 8 mM concentration. The findings suggest that ZnO NPs could be utilized as antibacterial agents and for shelf-life extension in food preservation.
Показать больше [+] Меньше [-]Microbiological and Chemical Studies on Edible Fresh Table Eggs
2023
Esmat I. Awad | Salah F. Abdlaal | Mohamed A. Bayoumi | Sameh M. Halawa
The aim of the present study was to assess the quality of table eggs produced in battery and floor production systems. Storage of table eggs in refrigerator is a popular practise; it may lead to increase the risks of eggs contamination. A total of 100 table eggs were collected from battery and floor farms in Sharkia province and then stored in refrigerator at 4°C. The collected eggs were divided into two groups (50 of each). Each group was divided into five sub-groups for examination: at laying time, 7th, 14th, 21st, and 28th days. They were subjected to physical, chemical, and microbiological examination of eggshells and internal contents. The results of the current study indicated that the storage had a major effect on the egg quality parameters including eggs, albumen, and yolk weights and internal contents pH, in both battery and floor eggs. In addition, the microbiological examination showed that the eggshells, particularly in the floor system, were higher in bacterial contamination with E. coli and Salmonella than the internal contents. The egg quality traits that were done by this study help to protect consumers against foodborne diseases.
Показать больше [+] Меньше [-]Genetic Diversity of Multiple Antibiotic Resistance Streptococcus agalactiae Isolated from Bovine Mastitis and Retail Markets Milk by Enterobacterial Repetitive Intergenic Consensus PCR (ERIC-PCR)
2023
Alaa Abd-Elfatah | Rasha Elkenany | Gamal Younis
Public health is at risk because Streptococcus agalactiae is increasingly linked to incidences of bovine mastitis in Egypt. In this study, enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) were used to explore the genotyping of several antibiotic resistant Streptococcus agalactiae isolated from bovine mastitis and retail milk. Also, antimicrobial resistance genes were detected. Two hundred and sixty-six (46.7%) strains were isolated from samples of milk obtained from cases of bovine mastitis in dairy farms and retail markets representing 34 (5.96%) Streptococcus agalactiae and 232 (40.7%) other Streptococcus species strains based bacterial identification. By using of disc diffusion assays, it was examined the susceptibility of all Streptococcus isolates to twelve antimicrobial agents. The highest prevalence of resistance of Streptococcus species was observed against ampicillin (65.5%), amoxicillin (56%), tetracycline (52.5%), ofloxacin (47.8%), and nitrofurantoin (46.9%). High proportion of the S. agalactiae isolates were resistance to amoxicillin (83%), followed by tetracycline (82.4%), nitrofurantoin (64.7%), azithromycin (61.8%), and ampicillin (50%). Most (88.2%) of S. agalactiae showed multiple antibiotic resistances (MAR) phenotypes with MAR index of 0.1-0.7 and 28 different MAR patterns. The results of genetic antimicrobial resistance of S. agalactiae strains revealed amplification of blaTEM (23%) and blaCTX (26%) genes in β-lactam-resistant strains, erm(B) gene (20%), mef(A) (35%) in macrolides resistant isolates, and tet(M) in (44%) tetracycline resistant strains. Using ERIC-PCR, the present study showed the genetic diversity and heterogeneity among S. agalactiae strains (n=34) that were classified into 19 distinct ERIC-PCR groups (A–S). Between them, ERIC O (20.6%, 7) was the most widespread group. These results indicated that milk samples served as source of MAR S. agalactiae, consequently posing threats to public health, so the improvement of the hygiene regimen on the farms and promotion of the wise use of antimicrobials are necessary. The obtained findings showed that milk samples were a source of MAR S. agalactiae, endangering public health. As a result, it is essential to enhance farm hygiene practices and promote the responsible use of antimicrobials. Additional research on the epidemiology of S. agalactiae is required to add bacterial genetic information in order to help in rational vaccine strategy in the future.
Показать больше [+] Меньше [-]Application of Bacteriophages for Biocontrol of Extensively Drug Resistant Salmonella Serovars Isolated from Poultry Farms
2023
Alaaeldin M. Saad | Mai F. Saad | Azza S. El-Demerdash | Marwa M. Seliem | Alaa H. Sewid
Salmonella is one of the most common foodborne pathogens causing diseases in humans and animals. Increased resistance to antibiotics necessitates the need for an alternative control strategy. This study aimed to screen, isolate and evaluate the bacteriophage characteristics for biocontrol of pathogenic Salmonella serovars. Twelve Salmonella isolates, including different Salmonella enterica serovars, were obtained from different sources of poultry farms. All isolates were screened for antibiotic sensitivity and showed multiple antibiotic resistance. Two lytic bacteriophages, vB_SalSph_WW1, and vB_SalM_WW2, were isolated from the sewage and characterized against Salmonella enterica serovar Enteritidis. Morphological analysis by transmission electron microscopy revealed that the vB_SalSph_WW1 phage belonged to the family Siphoviridae while the vB_SalM_WW2 phage belonged to the family Myoviridae. Both phages showed a broad host range within the Salmonella genus. Phages vB_SalSph_WW1 and vB_SalM_WW2 had a lytic effect on 3 (25%) and 4 (33.3%) of the 12 Salmonella isolates, respectively. The lytic cycle of each phage was determined by a one-step growth curve and both phages had the same short latent period (15 min). WW1 phage gave a burst size of 90 PFU/infected cell, while the vB_SalM_WW2 phage gave a higher burst size of 150 PFU/infected cell. The stability test revealed that vB_SalSph_WW1 and vB_SalM_WW2 phages were stable at pH 4–9 and pH 4–10, respectively. Both Phages exhibited high degrees of thermal tolerance with active titer as high as 42◦C. However, they lost their stability and the titers declined when heated at 50◦C for 30 min. This study revealed that vB_SalSph_WW1 and vB_SalM_WW2 phages have the potency to be used as an alternative strategy to control the infection of Salmonella in poultry farms and to prevent transmission of Salmonella infection to humans and spread of the pathogen into environment.
Показать больше [+] Меньше [-]Genotypic and Phenotypic Variation of Yersinia enterocolitica Isolated from Different Sources
2023
Maarouf A. Ahmed | Suzan F. Elsisy | Amany O. Selim
Yersinia enterocolitica is an enteropathogen that widely distributed in nature with high public health relevance and transmitted mostly by contaminated food. This study aimed to study the prevalence; phenotypic and genotypic characterization of the isolated Y. enterocolitica strains from 175 random samples of cow milk; beef; chicken meat; diarrheic cow and sheep faeces(35 for each), collected from different shops; dairy herds and sheep flocks, at Kaliobia Governorate Egypt, beside, investigation of the possible relationships among the isolated Y. enterocolitica strains. The obtained results revealed that 18 Y. enterocolitica isolates were recovered; they were isolated from cow milk samples (6/17.1%); chicken meat (5/14.3%); beef (4/11.4%) and cow faeces (3/8.6%), but failed to be isolated from sheep faeces. Four biotype groups (four 1A; seven 1B, three biotype 3 and four biotype4) were recognized biochemically. Moreover, many phenotypic virulence factors detected in some isolates as hemlysin , lecithinase, lipase ,proteinase and biofilm formation the isolated Y. enterocolitica were highly resistant for Penicillin G. ; ampicillin ; tetracycline ; amoxicillin and streptomycin ,but they were highly sensitive to meropenem ; norfloxacin ; ciprofloxacin ; gentamycin and Florfenicol. PCR appeared that, the ail gene was amplified in five and yst gene in four out of eight studied Y. enterocolitica strains. ERIC PCR showed many bands from 214 to 1228 and divided the 8 isolate to three genotypes. In conclusion, Y. enterocolitica strains with multiple antimicrobial resistances were isolated from milk, beef, chicken meat, cow faeces and could represent a public health concern. So, strict hygienic measures should be applied to minimize Y. enterocolitica contamination in milk and meat, also the antimicrobial resistances of Y. enterocolitica isolates should be monitored continuously to avoid public health hazards.
Показать больше [+] Меньше [-]Quality Assessments of Aflatoxin M1 Residues in Milk and Some Milk Products in Dakahlia Governorate
2023
Heba Fathy | Mohammed El-Sherbini | Maha Sabry | Adel AbdelKhalek
This work was planned to qualitatively assess AFM1 residues in milk as well as milk product samples. Cow’s raw milk, Aged Roomy cheese, Domiati and Kariesh cheese (50 of each type) were collected from various supermarkets in Mansoura governorate in Egypt during 2020-2022. Samples were tested using the TLC method, positive samples from TLC method were exposed to the HPLC method for detection of their levels and their concentrations were compared with the permissible limits. The obtained results showed high incidence in raw cow milk (36%) followed by fresh Kariesh cheese (28%), then aged roomy cheese (24%), and then Damietta cheese (12%) collected from the local markets in Mansoura by TLC. The obtained concentrations in analyzed dairy samples were compared with the Permissible Limits (PL) set by the concerning agents [US, EU] by quantitative detection using HPLC. The detectable concentration of AFM1 in raw milk and cheese by HPLC showed high concentration of aflatoxin M1 in aged roomy cheese (121.08) followed by raw cow milk (80.83), followed by fresh Kariesh cheese (50.14), and then Damietta cheese (35.33) collected from the local markets in in Dakahlia governorate. The current study's findings showed that raw milk and cheese sold in Mansoura city are occasionally contaminated with AFM1. As a result, it is strongly advised to effectively heat treat raw milk and give animals nutrition free of aflatoxins.
Показать больше [+] Меньше [-]Microbial Quality of Tilapia nilotica in Egypt: A Review
2023
Alaa Eldin M.A. Morshdy | Mohamed A. Hussein | Eman A.M. Elessawy | Wageh Darwish
Fish is considered as important source of animal derived protein, omega-3-fatthy acids, minerals such as calcium, phosphorus, iodine, and vitamins. Among the fish species, tilapia nilotica is the most famous fish in Egypt due to its ease culturing, short production cycle, cheap price, and therefore play fundamental roles in food security, particularly in the human supply of the anumal-derived protein. Fish during its production till delivery to the consumer's table might be exposed to a vast array of microbial contaminants either originated from its surrounding eniveronment or via cross contamination from the angler's hands, during transportation, and storage. Therefore, tilapia might act as a potential source of spreading of foodborne pathogens to the consumers. However, few reports had investigated the microbal quality of tilapia, particularly in Egypt. Therefore, this review was undertaken to report literatures studying the prevalence of some foodborne pathogens in tilapia fish in Egypt, the factors that affect the microbial quality of the fish, and some recommendations in order to extend the shelflife and improve the microbial quality of Tilapia nilotica. This reviw concluded that tilapia is eligible for contamination with a vast array of microorganisms such as enterobacteriacae, Staphylococcus aureus, Shewanella putrefaciens, Corynebacterium urealyticum, Aeromonas hydrophila, and Flavobacterium spp. Therefore, it is highly recommended to have efficient cooking of fish either via boiling, grilling, panfrying, dipping in liquid smokes, irradiation, ozonization, and addition of smone natural addirives such as lemon juice.
Показать больше [+] Меньше [-]A Review on the Microbial Surface Contaminants of the Animal Carcasses
2023
Alaa Eldin M.A. Morshdy | Salah M.I. Mehrez | Ahmed E. Tharwat | Karima M.E. Abdallah | Wageh Darwish
The flesh of the slaughtered animals is believed to be sterile. However, after slaughter, meat of different animal species is exposed to a vast array of microorganisms during processing of the carcasses. Carcass processing includes slaughtering, dressing, evisceration, quartering, and further transportation, and distribution. Several sources of microbial contamination might contribute to the microbial status of the different carcasses including internal sources such as the ruminal content of the animal, blood, hide and skin, and external sources such as butchers hands, clothes, knives, cutting boards, and abattoir environment including walls, floors, washing water, etc. One major task of the food safety sector is to ensure the hygienic measures adopted during all steps of meat processing. Therefore, this study was undertaken to review the microbial surface contaminants of the animal carcasses. This review concluded that efficient hygienic measures should be adopted during all steps of handling of the meat in order to obtain a high keeping quality meat with low initial microbial load.
Показать больше [+] Меньше [-]Monitored Variations in Microbial Load of Aquacultured Tilapia Fish in Kafr El-Sheikh and El-Faiyum Governorates, Egypt
2023
Neveen M. Abdelmotilib | Mohamed A. Seleem | Mohamed Bedair M. Ahmed | Rania E. Elgammal
The main aim of the Egyptian government is not only to increase tilapia fish production, but also to improve the quality of the fish produced. Contaminated water causes damage to farmed fish and is also considered an important factor affecting the fish quality. To avoid losses in fish farms, it is critical to obtain information on the microbial load. This research aimed to study the microbial load in four fish farms in the governorates of Kafr El-Sheikh and El-Faiyum (two farms in each governorate), in Egypt. Water and fish samples were collected at various locations within each farm pond for two seasons (autumn and spring) to assess the microbiological characteristics. Total coliform count of aquaculture water samples was the highest mean count of 3.93×103±1.81×103 CFU/ml in farm (3) of El-Faiyum. However, Clostridium counts were highest in farm (2) of Kafr El-Sheikh at 1.85×102 ±1.76×102 in autumn of 2021. Total coliform count (1.196×103±8.38×102) was the highest in farm (1) of Kafr El-Sheikh in spring 2022. Also, Salmonella spp. was only detected in farm (2) of Kafr El-Sheikh in autumn 2021, but in spring 2022 it was positive in farm (3) of El-Faiyum. Nevertheless, Listeria spp. was not detected in the aquaculture water samples examined. In addition, Salmonella spp. was detected in farm (1) of Kafr El-Sheikh and in farms (3 and 4) of El-Faiyum in spring 2022. It was concluded that the presence of pathogenic bacteria such as Staphylococcus aureus, Salmonella and Clostridium in fish samples in some farms in Kafr El-Sheikh and El-Faiyum may contribute to foodborne illness. So that, the microbiological criteria are recommended to be applied as guidelines to develop additional control programs in fish farms. This can help in the pollution control of the agricultural drainage water that is used in aquaculture; consequently, prevent the growth and toxin production by pathogens
Показать больше [+] Меньше [-]Choline and Vitamin E Combination Alleviates Biochemical, Molecular and Histopathological Effects of Non-alcoholic Fatty Liver Disease in Rats
2023
Omnia M. Abdelrahman | Medhat Fawzy | Mohammed Fouad Mansour
A sedentary lifestyle with a poor diet is associated with non-alcoholic fatty liver disease (NAFLD) occurrence. An increase in the NAFLD prevalence is associated with an increase in obesity in the world. Choline as a lipotropic factor and vitamin E as an antioxidant would possess beneficial effects in NAFLD treatment. This study aimed to investigate the synergistic effect of choline and vitamin E on lipid profile, liver function enzymes, antioxidant status and hepatic lipid metabolism-related genes. Albino rats (n=50) were randomly divided into 5 groups. G1: Control group (n= 10), G2: Rats were induced by NAFLD (n=10), G3: Rats were induced by NAFLD and received low dose of choline (25 mg/kg BW orally) and vitamin E (50 mg/kg BW orally), G4: Rats were induced by NAFLD and received medium dose of choline (50 mg/kg BW orally) and vitamin E (100 mg/kg BW orally), G5: Rats were induced by NAFLD and received high dose of choline (100 mg/kg BW orally) and vitamin E (200 mg/kg BW orally). The results demonstrated that treatment of rats with different doses of choline and vitamin E significantly decreased AST, ALT, ALP, GGT, TC, TG, LDL, VLDL, plasma glucose, hepatic lipid peroxidation (MDA), hepatic mRNA expression of inflammatory cytokines (IL-1β and TNFα) and mRNA expression of hepatic SREBP-1c in compared to NAFLD group. Moreover, significant increase of total protein and albumin, HDL, insulin, antioxidant enzymes (SOD and catalase), mRNA expression of fatty acid oxidation genes (PPAR-α and CPT-1), mRNA expression of hepatic PEMT was detected in treated groups in compared to NAFLD group. In conclusion, choline and vitamin E combination alleviates the biochemical, molecular and histopathological effects of NAFLD in rats with a potential effect to the highest dose of this combination.
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