Evaluation of the Antimicrobial Activity of Four Plant Essential Oils against Some Food and Phytopathogens Isolated from Processed Meat Products in Egypt

Synthetic preservatives are widely utilized by the food industry to inhibit the microbial contamination and increase food safety and shelf life. The excessive utilization of synthetic preservatives can have a negative impact on human health and the environment. There is a great interest to find out natural substances as possible food-preservatives. The consumers' preference for food products with natural ingredients prompted food manufacturers to utilize natural-based preservatives in their production. It is worth noting that plant essential oils (EOs) among the natural-based substances have been efficiently used as antimicrobial agents against phyto- and food pathogens. The current study was conducted to evaluate the microbial contamination of three industrial meat products from five governorates in Egypt, identify the predominant bacterial and fungal isolates and determine the antimicrobial efficacy of some EOs (thyme, fennel, anise and marjoram) against the most predominant microbial isolates. A sensory test was also performed to estimate the customer preferences for specific organoleptic aspects of meat products after EOs treatment. Results showed that there is a promising antimicrobial activity of all studied EOs against some microbial isolates in a dose-dependent manner. In particular, thyme EO showed the highest significant antibacterial activity against P. fluorescence and E. coli. Whereas the marjoram EO showed the highest activity against P. aeruginosa. In addition, the sensory test revealed that the treatment with anise and marjoram EOs showed the highest acceptability by the testers and did not show significant differences on the organoleptic properties with respect to control. As overall, the obtained results of the current research are promising and proved feasibility of employing plant EOs as possible preservatives for processed meat products

Bacteriological Quality of Retailed Chicken Meat Products in Zagazig City, Egypt

Chicken meat products have a high biological value; they are good sources of amino acids, vitamins, and minerals. Despite this high biological value, these products act as a good substrate for different types of bacteria and have been implicated in many foodborne disease outbreaks. Therefore, a total of 60 random samples of chicken meat products (nuggets, luncheon and pane, 20 of each) were collected from Zagazig City, Sharkia Governorate, Egypt for bacteriological examination (Aerobic Plate Count, Staphylococci count, Pseudomonas count, determination of most probable number of Coliform and E. coli.). The obtained results revealed that the mean aerobic plate counts were 5.18±0.19, 4.88±0.20 and 4.73±0.29 log10 CFU/g; Staphylococci counts were 2.96±0.20, 3.14±0.21 and 3.32±0.16 log10 CFU/g; Pseudomonas counts were 2.17±0.30, 2±0.28 and 2.34±0.21 log10 CFU/g; most probable numbers of Coliforms were 3.37±0.11, 3.83±0.27 and 3.64±0.30 log10 CFU/g; and most probable numbers of E. coli were 2.14±0.17, 2.56±0.30 and 2.64±0.25 log10 CFU/g in the examined nuggets, luncheon and pane, respectively. According to the Egyptian Organization for Standardization and Quality (EOS), the examined chicken product samples were 10(21.67%), 9(15%), 28(46.67%), 49(81.67%), 31(51.67%) and 30(50%) accepted for aerobic plate count, Staphylococci count, S. aureus, Pseudomonas count, Coliform and E. coli, respectively. In conclusion, the examined chicken meat products revealed unsatisfactory hygienic measures. Therefore, strict hygienic practices should be adopted during processing of chicken meat products to improve the bacteriological quality of such products

Prevalence of Antibiotic-Resistant Vibrio Isolated from Some Marketed Fish in Egypt with a Decontamination Trial by Lemon juice

      Vibrio species are major sea foodborne pathogens that cause gastroenteritis as a serious disease of human public health due to the consumption of undercooked or raw fish. In the current study, a total of 100 fish samples (Nile tilapia, Nile perch, Meagre, and Sea bass) were collected randomly from retail markets in Egypt to investigate the prevalence of Vibrio species. The results revealed that Vibrio species isolated with an overall percentage of 52% of all examined fish. Bacteriological and chemical examinations revealed 42.3% V. parahaemolyticus, 26.92% V. mimicus, 19.23% V. alginolyticus, 9.62% V. vulnificus and 1.92%V. cholera. Antibiotic sensitivity declared high resistance of the isolates to different antimicrobial agents used in Egypt including Ampicillin (100%), Nalidixic acid (88.3%), Streptomycin (84.2%), Sulphamethoxazol (70.7%) and Oxytetracycline (64.8%) and it had sensitivity to Amikacin (94%), Ciprofloxacin (70.5%), Gentamicin (58.9%) with an average MAR index of 0.576. By polymerase chain reaction, all examined Vibrio isolates were positive for 16SrRNA specific for Vibrio spp. and harbored toxR gene virulence gene.  Finally, dipping of tilapia in lemon juice 5% for 2 h reduced V. parahaemolyticus count by 0.42log cfu/g (62.08%). Consequently, hygienic measures should be approved to control the contamination of fish in the markets and the aquatic environment. Regular monitoring of fish for antibiotic resistance by Vibrio species, and their molecular characterization is necessary to improve the safety of seafood. Dipping fish in lemon juice is an efficient strategy for reducing V. parahaemolyticus load in fish

A Review: Accumulation of Toxic Metals among Meat from Different Species

Meat contamination is a problem that must be addressed since it can affect consumers' health. Standard acceptable limits for heavy metals in meat and organs have been established by many international organizations. Livestock including sheep, cattle, camels, and goats side by side with other poultry species are the most significant sources of meat for protein. Heavy metal contamination in animal products may be harmful to people's health. The earth's crust naturally contains heavy metals, but uncontrolled human activity has significantly changed their geochemical cycles and biological equilibrium. This causes a buildup of metals in animal tissue that contain secondary metabolites, which gives rise to a specific pharmacological action. Humans can have negative health effects from prolonged exposure to heavy metals as lead, cadmium, arsenic, and mercury. This review showed that most of the studies conducted in different countries on heavy metals were mostly in red meat, and the research was few in the cases of domesticated birds and very rare in game birds, although it is considered a good example for investigating heavy metals in the environmen

Prevalence of Listeria Monocytogenes in Meat Products Retailed in Egypt and Worldwide: A Review

Meat products are regarded as major sources of essential amino acids, minerals, and vitamins. However, during all stages of the processing of meat products, including the slaughter of the animal, dressing, evisceration, and subsequent transportation and distribution, may expose the product to a wide range of bacteria. The microbial community of the finished goods may be influenced by handling and raw materials used in the production of the meat products. The microbiological condition of meat products may be affected by a number of factors, including worker hands, clothing, knives, cutting boards, slaughterhouse and meat processing plant environments, including walls, floors, washing water, etc. Listeria monocytogenes (L. monocytogenes) is considered as one important foodborne pathogen that is responsible for many cases of food poisoning among consumers worldwide. This study aimed at investigating the current scenario of the prevalence of L. monocytogenes in retailed meat products in Egypt and worldwide. The cited literatures in the current review demonstrated that effective sanitary practices should be used throughout all phases of handling meat to produce meat products with a high level of storage quality and free from L. monocytogenes

Heavy Metal Content in Chicken Meat Products: A Health Risk Assessment Study

There is an increasing demand for chicken meat products due to their high nutritive value, specific aroma and flavor, and cheap price compared to red meat. However, there is a clear lack of information on the residual content of toxic metals such as lead (Pb), cadmium (Cd), mercury (Hg), and trace elements such as zinc (Zn), and copper (Cu) in such products. Therefore, this study was undertaken to estimate the residual contents of Pb, Cd, Hg, Zn, and Cu in five chicken meat products including chicken burger, chicken fillet, chicken luncheon, chicken nuggets, and chicken panne. Moreover, estimated daily intakes (EDI), and the potential health risks of heavy metals due to consumption of such meat products were calculated for Egyptian adults and children. The achieved results indicated no detection of Hg in any sample. However, the other measured elements were detected in all examined chicken meat product samples at variable concentrations. The chicken burger had the highest metal concentrations. Several samples had higher Pb and Cd levels than the set maximum permissible limits. However, the calculated EDI, hazard ratio, and hazard index revealed no potential risks associated with the consumption of such chicken meat products among Egyptian adults and children

Virulence and Antimicrobial Resistance Profiling of Aeromonas hydrophila Recovered from Retail fish in Sharkia Province, Egypt

Fish is one of the most important foods because of its high nutritional value, high palatability, and easy digestion. At the same time, it acts as a vehicle for many types of pathogenic microorganisms especially Aeromonas species, which results in public health hazards. Therefore, the present study was conducted to evaluate the prevalence of Aeromonas species in fresh fish (catfish, mullet, lizardfish, and coralfish) marketed in Zagazig city, Sharkia Governorate, Egypt. In addition, multiplex PCR was performed to detect some virulence-associated genes in A. hydrophila isolates. Furthermore, antimicrobial susceptibility testing was carried out on A. hydrophila isolates using commonly used antimicrobials in Egypt through the disc diffusion method. The achieved results indicated contamination of fish with different species of Aeromonas such as A. veronii, A. sobria, A. caviae and A. hydrophila. The results revealed that Aeromonas species isolated with an overall percentage of 55% of all examined fish. Bacteriological examinations revealed 20% A. hydrophila, 20% A. sobria, 10% A. caviae and 5% A. veronii. Antibiotic sensitivity declared high resistance of the isolates to different antimicrobial agents used in Egypt, including penicillin (100%), Ampicillin (90.0%), Streptomycin (90.9%), Cephalothin (72.7%), Tetracycline (72.7%), Cefotaxime (63.6%), and Sulfamethoxazole (54.5%). Therefore, hygienic measures should be adopted to control microbial contamination either in the aquatic environment or in fish markets

Bioactivity of Essential Oils for Mitigation of Listeria monocytogenes Isolated from Fresh Retail Chicken Meat

Listeria monocytogenes is one of the most severe foodborne pathogens found in several habitats. Therefore, this study aims to investigate the antilisterial activity of different essential oils (EOs) against multidrug-resistant (MDR) L. monocytogenes strains isolated from fresh chicken meat. Our results showed that the prevalence of L. monocytogenes in the examined samples was 48%. Seventy-eight isolates were identified as L. monocytogenes. Out of these, 64.1% were categorized as MDR and were categorized in 18 patterns with 50 MDR isolates. One isolate was selected randomly from each pattern to investigate their biofilm-forming ability, resistance, and virulence genes incidence. Out of 18 MDR isolates, 88.9% showed biofilm-forming ability. Moreover, the most prevalent resistance genes were ermB (72%), aadA (67%), penA (61%), and floR genes (61%). However, the most prevalent virulence genes were inlA (94.4%), prfA (88.9%), plcB (83.3%), and actaA (83.3%). The antilisterial activity of EOs showed that cinnamon bark oil (CBO) was the most effective antilisterial agent. CBO activity could be attributed to the bioactivity of cinnamaldehyde which effects cell viability by increasing the bacterial cell electrical conductivity, ion leakage, and salt tolerance capacity loss. Therefore, CBO could be an effective alternative natural agent for food safety applications

Potential of Natural Phenolic Compounds as Antimicrobial Agents against Multidrug-Resistant <i>Staphylococcus aureus</i> in Chicken Meat

Staphylococcus aureus is one of the most widespread foodborne bacteria that cause high morbidity, mortality, and economic loss, primarily if foodborne diseases are caused by pathogenic and multidrug-resistant (MDR) strains. This study aimed to determine the prevalence of S. aureus in chicken meat in Egyptian markets. Thus, this study might be the first to assess the efficiency of different natural phenolic compounds as novel antibacterial agents against MDR S. aureus pathogens isolated from raw chicken meat in the Egyptian market. The incidence and quantification of pathogenic S. aureus were detected in retail raw chicken meat parts (breast, thigh, fillet, and giblets). In total, 73 out of 80 (91.3%) of the chicken meat parts were contaminated, with S. aureus as the only species isolated. Of the 192 identified S. aureus isolates, 143 were coagulase-positive S. aureus and 117 isolates were MDR (81.8%, 117/143). Twenty-two antibiotic resistance profile patterns were detected. One strain was randomly selected from each pattern to further analyze virulence and resistance genes. Extracted DNA was assessed for the presence of antibiotic-resistance genes, i.e., vancomycin-resistance (vanA), aminoglycosides-resistance (aacA–aphD), apramycin-resistance (apmA), and methicillin-resistance (mecA), penicillin-resistance (blaZ), and virulence genes staphylococcal enterotoxins (sea and seb), Panton–Valentine leucocidin (pvl), clumping factor A (clfA), and toxic shock syndrome toxin (tst). Clustering analyses revealed that six S. aureus strains harbored the most virulence and resistance genes. The activity of hydroquinone was significantly higher than thymol, carvacrol, eugenol, and protocatechuic acid. Therefore, phenolic compounds, particularly hydroquinone, could potentially alternate with conventional antibiotics against the pathogenic MDR S. aureus inhabiting raw chicken meat. Hence, this study indicates that urgent interventions are necessary to improve hygiene for safer meat in Egyptian markets. Moreover, hydroquinone could be a natural phenolic compound for inhibiting foodborne pathogens