Exploring the Function of Quorum Sensing Regulated Biofilms in Biological Wastewater Treatment: A Review.

Quorum sensing (QS), a type of bacterial cell-cell communication, produces autoinducers which help in biofilm formation in response to cell population density. In this review, biofilm formation, the role of QS in biofilm formation and development with reference to biological wastewater treatment are discussed. Autoinducers, for example, acyl-homoserine lactones (AHLs), auto-inducing oligo-peptides (AIPs) and autoinducer 2, present in both Gram-negative and Gram-positive bacteria, with their mechanism, are also explained. Over the years, wastewater treatment (WWT) by QS-regulated biofilms and their optimization for WWT have gained much attention. This article gives a comprehensive review of QS regulation methods, QS enrichment methods and QS inhibition methods in biological waste treatment systems. Typical QS enrichment methods comprise adding QS molecules, adding QS accelerants and cultivating QS bacteria, while typical QS inhibition methods consist of additions of quorum quenching (QQ) bacteria, QS-degrading enzymes, QS-degrading oxidants, and QS inhibitors. Potential applications of QS regulated biofilms for WWT have also been summarized. At last, the knowledge gaps present in current researches are analyzed, and future study requirements are proposed.

Ensuring safety and improving keeping quality of meatballs by addition of sesame oil and sesamol as natural antimicrobial and antioxidant agents.

The antioxidant and antimicrobial effect of sesame oil (10, 30, and 50 g/kg) and sesamol (0.1, 0.3, and 0.5 g/kg) in meatballs during cold storage for 18 days at 3 ± 1 °C was investigated. Sesame oil and sesamol did not alter the sensory attributes of meatballs. Addition of either sesame oil or sesamol significantly delayed lipid oxidation when compared with control. Sesamol exhibited more potent antioxidant activities more than sesame oil. During storage, the aerobic plate counts (APCs) and Enterobacteriaceae counts (EBCs) were markedly (P < 0.01) decreased in meatballs treated with sesame oil or sesamol in comparison with untreated control samples. Control meatballs showed signs of quality deterioration at day 7 of storage, while treated meatballs exhibited longer shelf lifes ranged from 9-18 days according to sesame oil or sesamol concentrations. Both sesame oil and sesamol induced marked (P < 0.01) decline in the counts of E. coli O157:H7, Salmonella enterica serovar Typhimurium, Staphylococcus aureus and Listeria monocytogenes that artificially inoculated to meatballs. Sesamol was more effective than sesame oil in the reduction of APCs, EBCs as well as foodborne pathogens. The results suggest that both sesame oil and sesamol are potentially useful natural additives to fresh meat products for improving its microbial quality and extending its shelf life during cold storage.

Occurrence and Antimicrobial Susceptibility Profile of Salmonella spp. in Raw and Ready-To-Eat Foods and Campylobacter spp. in Retail Raw Chicken Meat in Transylvania, Romania.

The survey was undertaken to investigate the presence and antimicrobial susceptibility profile of Salmonella spp. in raw and ready-to-eat (RTE) foods, and Campylobacter spp. in the retail raw chicken meat collected in two counties of Transylvania, Romania. A total of 13.1% (51/388) of the examined food samples were found to be Salmonella positive, with a distribution of 14.7% (48/326) in the raw food (i.e., pork, chicken carcass, and shell egg) and 4.8% (3/62) in the RTE samples (i.e., sausages, but not ham and salami), respectively. These differences were statistically significant (p = 0.034). The isolates were serotyped as Salmonella Infantis (n = 19), Salmonella Typhimurium (n = 11) Salmonella Rissen (n = 8), Salmonella Derby (n = 3), Salmonella Enteritidis (n = 3), Salmonella Bredeney (n = 2), Salmonella Brandenburg (n = 1), Salmonella Gloucester (n = 1), Salmonella Goldcoast (n = 1), Salmonella Kottbus (n = 1), and Salmonella Ruzizi (n = 1). Campylobacter strains were present in 29.4% (10/34) of the investigated chicken samples, and the identified species were Campylobacter coli (70%) and C. jejuni (30%). From the 14 tested antimicrobials, the Salmonella isolates were resistant against azithromycin (88.2%), tetracycline (54.9%), sulfamethoxazole (54.9%), ciprofloxacin (45.1%), nalidixic acid (43.1%), ampicillin (35.3%), chloramphenicol (33.3%), tigecycline (25.5%), cefotaxime (13.7%), colistin (13.7%), trimethoprim (7.8%), and gentamicin (2%), resulting in the expression of 21 multidrug-resistant (MDR) profiles. Of 10 Campylobacter isolates, 80% were resistant to ciprofloxacin and nalidixic acid, 40% to tetracycline, and 10% to streptomycin and erythromycin, respectively. Our findings indicate that Romanian isolates of Salmonella spp. and Campylobacter spp., contaminating animal-origin foods, can exhibit MDR patterns, representing a public health risk.

First study in the frequency of isolation and phenotypic antimicrobial resistance profiles of pig and cattle origin Campylobacter strains in Romania.

Campylobacter spp. is recognized as one of the most common pathogens involved in the development of gastrointestinal infections in humans. The current study aimed to enhance the knowledge on the occurrence and molecular characterization of Campylobacter spp. in pigs and cattle origin caecum samples (n = 56) collected in one year, from nine Romanian slaughterhouses, and to determine the antimicrobial resistance profile of the isolated strains. All Campylobacter spp. strains (n = 41) isolated from swine and cattle caecum samples were analyzed in terms of antimicrobial resistance, in accordance with the EURL protocol and with the Commission Implementing Decision No. 2020/1729. The prevalence rate for C. coli. in pig caecum samples was 92.3% (36/39), and the prevalence of C. jejuni, in cattle origin samples was 29.4% (5/17). C. coli strains isolated from pigs proved resistant to tetracycline 75% (27/36), ciprofloxacin 69.4% (25/36), erythromycin 8.3% (3/36), ertapenem 2.8% (1/36) and gentamicin 2.8% (1/36), but no resistance was observed towards chloramphenicol. C. jejuni strains originating from cattle expressed resistance to ciprofloxacin 60.0% (3/5) and tetracycline 20.0% (1/5), but they were susceptible to chloramphenicol, erythromycin, ertapenem and gentamicin. In the present study, 19.5% (7/36) C. coli strains isolated from pigs were identified as multidrug-resistant (MDR) bacteria. The obtained results demonstrated that pigs especially, but cattle to, can be considered important natural reservoirs for zoonotic multidrug-resistant Campylobacter strains, having a stimulating effect for further studies aiming at the molecular screening of the genotypic antimicrobial resistance processing of a higher number of samples.

Multidrug-Resistant Proteus mirabilis and Other Gram-Negative Species Isolated from Native Egyptian Chicken Carcasses.

Poultry carcasses may be reservoirs for the zoonotic transmission of antimicrobial-resistant bacteria to humans and pose a major public health hazard. During the isolation of Salmonella from poultry and other foods, many of the presumptive typical Salmonella colonies on xylose lysine deoxycholate (XLD) agar were found to lack the invA gene, which is the specific target gene for Salmonella spp. Therefore, the current study aimed to estimate the prevalence and antimicrobial resistance profiles of extensively drug-resistant invA-negative non-Salmonella isolates recovered from native Egyptian chicken carcasses as presumptive Salmonella colonies on XLD agar. The non-Salmonella isolates were detected in 84% (126/150) of the examined native Egyptian chicken carcasses and classified into five genera, with prevalence rates of 64% (96/150), 14% (21/150), 6.7% (10/150), 3.3% (5/150), and 1.3% (2/150) for Proteus, Citrobacter, Shigella, Pseudomonas, and Edwardsiella, respectively. One hundred and ninety-five invA-negative, non-verified presumptive Salmonella isolates were recovered and classified at the species level into Proteus mirabilis (132/195; 67.7%), Proteus vulgaris (11/195; 5.6%), Citrobacter freundii (26/195; 13.3%), Shigella flexneri (8/195; 4.1%), Shigella sonnei (6/195; 3.1%), Shigella dysenteriae (3/195; 1.5%), Pseudomonas fluorescens (6/195; 3.1%), and Edwardsiella tarda (3/195; 1.5%). All (195/195; 100%) of these isolates showed resistance against cefaclor and fosfomycin. Additionally, these isolates showed high resistance rates of 98%, 92.8%, 89.7%, 89.2%, 89.2%, 86.7%, 80%, 78.5%, 74.4%, and 73.9% against cephalothin, azithromycin, vancomycin, nalidixic acid, tetracycline, sulfamethoxazole/trimethoprim, cefepime, gentamicin, cefotaxime, and ciprofloxacin, respectively. Interestingly, all (195/195; 100%) of the identified isolates were resistant to at least five antibiotics and exhibited an average MAR (multiple antibiotic resistance) index of 0.783. Furthermore, 73.9% of the examined isolates were classified as extensively drug-resistant, with an MAR index equal to 0.830. The high prevalence of extensively drug-resistant foodborne Proteus, Citrobacter, Shigella, Pseudomonas, and Edwardsiella isolated from native chicken carcasses poses a great hazard to public health and necessitates more monitoring and concern about the overuse and misuse of antibiotics in humans and animals. This study also recommends the strict implementation of GHP (good hygienic practices) and GMP (good manufacturing practices) in the chicken meat supply chain to protect consumer health.

Evaluation of Antimicrobial Resistance Profiles of Bacteria Isolated from Biofilm in Meat Processing Units.

The aim of this study was to assess the hygiene of pork, beef, and poultry carcasses and to determine the phenotypic antibiotic susceptibility of the bacteria embedded in the biofilm formed on the carcasses kept in cooling chambers for at least three days. The level of hygiene was assessed by determining the total aerobic colony count (TACC) and the Enterobacteriaceae level in different sampling points of the carcasses, along with the detection of E. coli and Pseudomonas spp. embedded in the biofilm. Furthermore, the E. coli and Pseudomonas spp. isolates were tested for antimicrobial resistance profiles. A total of 130 samples collected from pork, beef, and poultry from processing units were analyzed to determine the total aerobic colony count as well as to measure the level of Enterobacteriaceae found on the carcasses. The antimicrobial susceptibility of 44 Escherichia coli and eight Pseudomonas spp. strains isolated from the carcasses were assessed using the Vitek 2 system using two different cards. Overall, the regulatory limits for the TACC were exceeded in 7.6% of the samples, and 65% of the samples exceeded the regulatory limits for Enterobacteriaceae levels. The antimicrobial susceptibility tests of the E. coli isolates analyzed with the AST-GN27 card revealed the highest resistance to be that towards ampicillin (76.1%), followed by cefazolin (71.4%), amoxicillin/clavulanic acid (61.9%), nitrofurantoin (52.3%), cefoxitin (47.6%), tetracycline (38.1%), piperacillin, norfloxacin (19%), trimethoprim-sulfamethoxazole (11.9%), cefotaxime (9.5%), ceftazidime, cefazolin, amikacin, gentamicin, and ciprofloxacin (4.7%). However, all of the isolates were sensitive to piperacillin-tazobactam and imipenem. Thirty-two (61.5%; 95% CI 47.9-73.5) out of fifty-two isolates exhibited multidrug resistance, resulting in the expression of 10 resistance profiles. The findings of this study highlight serious hygienic and sanitary deficiencies within the meat processing units and demonstrate that the resulting meat can harbor Multidrug-resistant Escherichia coli and Pseudomonas spp., both of which pose a serious public health risk. However, further research with a larger number of samples is required to reach thorough results.

Hazard Analysis and Critical Control Point (HACCP) Application to Dry-Cured Pastrami in Egyptian Pastrami Factories.

The current study established a HACCP tactic for all hazards related to Egyptian dry-cured pastrami production. All types of hazards that could occur at each production step were depicted. The fabrication steps of pastrami were originally based on the processes and conclusions presented in two previous publications by members of the research team; thus, the current scientific paper is considered a completion of the two previous publications. All operations executed and products manufactured outside the pastrami factory were excluded. The HACCP system was only applied to dry-cured pastrami production stages from receiving frozen raw meat and non-meat ingredients until packaging and storing the final product. Four CCPs were detected and taken into account. The permissible critical limits of additives and non-meat ingredients were considered. Suitable corrective actions were arranged. Regular HACCP plan review, proper recording of detected CCPs and critical limits were necessary for validation processes. Following up with the supply chain by obtaining the certified suppliers, together with the importance of the verification procedures of the elaborated HACCP plan, were essential in order to ensure the production of safe food without defects.

Estimated Prevalence of Tuberculosis in Ruminants from Slaughterhouses in Constantine Province (Northeastern Algeria): A 10-Year Retrospective Survey (2011-2020).

Tuberculosis (TB) is considered one of the most widespread and devastating zoonotic diseases in low-income countries, with a cosmopolitan distribution. The aim of this 10-year retrospective survey (from 2011 to 2020) was to determine the frequency of bovine, ovine, and goat tuberculosis in different local slaughterhouses across Constantine Province, Algeria. The control of livestock carcasses was systematically performed by veterinarian inspectors, after each stage of the slaughter process. The routine abattoir inspection included the detection of visible abnormalities on different organs and lymph nodes. The overall prevalence of tuberculosis recorded in slaughtered animals was 0.83%, with the following distribution among species: 2.73% in cattle, 0.001% in sheep, and 0.0% in goats. During the study period, there was a strong correlation (R = 0.82) (p < 0.01) between tuberculosis occurrence and the number of slaughtered cattle. Fluctuations in monthly TB prevalence ranged from 2% to 24.8% between 2018 and 2020, although there were no statistically significant correlations between infection and the age or gender of the animals, except for the year 2020 when a significantly higher (p = 0.017) percentage of TB cases were recorded in female cattle compared to male cattle. The average monthly weight of the confiscated livers and lungs ranged significantly (p ≤ 0.05) from 150 kg to 350 kg. The study results provide baseline data regarding livestock tuberculosis monitoring in the area of Constantine, Algeria, indicating that the disease incidence is not highly alarming, yet remains a serious public and animal health issue in the screened region.

Antimicrobial Effect of Moringa oleifera Leaves Extract on Foodborne Pathogens in Ground Beef.

Consumers nowadays are becoming more aware of the importance of using only meat products containing safe and natural additives. Hence, using natural food additives for extending the shelf life of meat along with delaying microbial growth has become an urgent issue. Given the increasingly popular view of Moringa oleifera leaves as a traditional remedy and also the scarcity of published data concerning its antimicrobial effect against foodborne pathogens in meat and meat products, we designed the present study to investigate the antimicrobial effect of Moringa oleifera leaves aqueous extract (0.5%, 1%, and 2%) on ground beef during refrigerated storage at 4 °C for 18 days. MLE revealed potent antimicrobial properties against spoilage bacteria, such as aerobic plate count and Enterobacteriaceae count. MLE 2% showed a significant (p < 0.01) reduction in the counts of E. coli O157:H7, Salmonella enterica serovar Typhimurium, and Staphylococcus aureus artificially inoculated to ground beef by 6.54, 5.35, and 5.40 log10 CFU/g, respectively, compared to control, by the 18th day of storage. Moringa leaves extract (MLE) had no adverse effect on the overall acceptability and other sensory attributes; moreover, it induced a slight improvement in the tenderness and juiciness of treated ground beef, compared to the control. Therefore, MLE can be used as a healthy, natural, and safe preservative to increase meat products' safety, quality, and shelf stability during cold storage. A promising approach for using natural food additives rather than chemical preservatives could begin new frontiers in the food industry, as they are more safe and do not constitute health risks to consumers.

Improvement of Microbial Quality, Physicochemical Properties, Fatty Acids Profile, and Shelf Life of Basa (Pangasius bocourti) Fillets during Chilling Storage Using Pepsin, Rosemary Oil, and Citric Acid.

Meat discoloration, lipid oxidation, and undesirable texture are inevitable phenomena in basa fish fillets during storage, which in turn limits their exportation as well as decreases consumer acceptability. In addition, increasing consumers' requirements for high-quality, minimally processed, and ready-to-cook fish fillets with an extended shelf-life is a great challenge, particularly with lifestyle changes. Accordingly, this study aimed to improve the quality, lipid stability, fatty acid profile, and lipid nutritional quality indices (LNQI) of basa fish fillets during chilling storage at 4 °C for 15 days using pepsin enzyme (E, 0.1%), rosemary oil (R, 0.5%), citric acid (CA, 0.5%), and their combination (0.1% E + 0.5% R; 0.1% E + 0.5% CA; and 0.1% E + 0.5% R + 0.5% CA). Our results revealed that all treated samples exhibited a significant increase in protein content, a significant decrease in fat content, and a marked reduction in pH, total volatile base nitrogen (TVBN), thiobarbituric acid (TBA), free fatty acids, and shear force (SF) values in comparison to control ones. Moreover, significant improvements in sensory scores, color stability, fatty acid profile, LNQI, and microbial quality of all treated samples were observed. Such findings were more pronounced in samples treated with a mixture of pepsin, rosemary, and citric acid (TVBN: 2.04 vs. 6.52 mg%; TBA: 0.40 vs. 2.68 mg malonaldehyde/Kg; and SF: 8.58 vs. 19.51 Kgf). Based on the obtained results, there was an extension for the shelf life of all treated basa fish fillet samples, especially in samples treated with a mixture of pepsin, rosemary, and citric acids when compared with the control samples (˃15 days versus 10 days). Additionally, eucalyptol, camphor, isoborneol, and α-pinene are the main components of rosemary, with great antioxidant and antimicrobial activity. In conclusion, the mixture of pepsin, rosemary, and citric acid can be applied easily in the seafood industry and at the household level to provide ready-to-cook fish fillets of high quality with great health benefits.

Causes of Post-Mortem Carcass and Organ Condemnations and Economic Loss Assessment in a Cattle Slaughterhouse.

The study was undertaken to investigate the main causes of carcass and organ condemnations, as well as to estimate the financial losses suffered by a cattle slaughterhouse. In this regard, an active abattoir survey, based on standard post-mortem inspection procedures for meat, was conducted on 151,741 cattle, from January 2021 to December 2022. Overall, 13.27% (n = 20,125) of the carcasses expressed lesions or pathological conditions and, out of them, 1.15% (n = 1738) were totally confiscated, while another 12.12% (n = 18,387) were partially admitted for human consumption. In the case of organs, the general inspection data reveal that 12.28% (n = 18,630), 7.56% (n = 11,477), 1.89% (n = 2862), and 0.27% (n = 412) of the examined liver, lung, heart, and kidney specimens presented one or more types of abnormalities. In addition, regarding the types of specific pathological findings, dystrophies/anomalies (69.8%), circulatory disorders (40.6%), fecal contamination (60.9%), and suspected bacterial/viral infections showed a dominant occurrence in the liver, lung, heart, and kidneys, respectively. Consequently, the total direct financial losses resulting from edible part condemnation over the two years was estimated at EUR 4,021,717.3, which represents 1.17% of the total achievable net revenue without carcass and organ condemnation. Of this, EUR 3,661,400.4 (1.07%) and EUR 360,316.9 (8.73%) was related to carcass and organ condemnation, respectively. The study results demonstrate that the post-mortem inspection of meat at the slaughterhouse level plays a crucial role in identifying pathological lesions, in addition to some other issues, such as fecal contamination or non-compliant laboratory results, relevant to both public health and economic factors.

Cefotaxime-, Ciprofloxacin-, and Extensively Drug-Resistant Escherichia coli O157:H7 and O55:H7 in Camel Meat.

The present study aimed to explore for the first time the occurrence and the antimicrobial resistance profiles of E. coli O157:H7 and O55:H7 isolates in camel meat in Egypt. Among the 110 camel meat samples examined using standardized microbiological techniques, 10 (9.1%) and 32 (29.1%) were positive for E. coli O157:H7 and E. coli O55:H7, respectively. In total, 24 isolates were verified as E. coli O157:H7, while 102 isolates were confirmed serologically as E. coli O55:H7. Multiplex PCR revealed the existence of eaeA, stx1, stx2, and EHEC-hlyA among E. coli O157:H7 and O55:H7 isolates (n = 126) at various percentages. According to their resistance against 14 antibiotics, 16.7% and 83.3% of O157:H7 isolates and 8.6% and 76.5% of O55:H7 isolates were classified into extensively drug-resistant and multi-drug-resistant, respectively, whereas 29.4% and 22.2% of E. coli isolates were resistant to cefotaxime and ciprofloxacin, respectively. The study results emphasize that camel meat may be a vehicle for multi- and extensively drug-resistant E. coli O157:H7 and O55:H7 strains, indicating a potential threat to public health. Further studies based on the molecular evidence of the antimicrobial resistance genes and enrolling a larger number of samples are recommended for a better understanding of the antimicrobial resistance phenomenon of camel-meat-originating pathogenic E. coli strains.

Nisin and Organic Acid Salts Improved the Microbial Quality, Extended the Shelf Life, and Maintained the Sensory Attributes of Semidry Beef Luncheon Marketed at Adverse (35-40 °C) Ambient Summer Temperatures.

Semidry beef luncheon may undergo deteriorative changes during storage at ambient temperatures in tropical and subtropical regions including Egypt. This study was conducted in a meat plant in Egypt with the aim of overcoming the economic losses from the returns of spoiled unsold beef luncheon displayed in grocery stores at adverse summer temperatures of 37 °C or more. Ten approaches were applied using different preservatives, comprising sodium nitrite, nisin, potassium sorbate, and organic acid salts (a combination of sodium lactate, sodium acetate, and sodium diacetate). In addition, the product was cooked at different temperatures and was stored for 21 days at 37 °C, during which time the shelf life, microbial quality, pH, and sensory attributes were investigated. By Day 21 of storage, the luncheon contained 50 mg/kg sodium nitrite, 25 mg/kg nisin, and 1000 mg/kg organic acid salts and, when cooked at a final core temperature of 92 °C, exhibited reductions in aerobic plate count, anaerobic plate count, lactic acid bacterial count, and mold and yeast counts by 4.32, 3.54, 3.47, and 1.89 log10 CFU/g, respectively, when compared with the control. The sensory attributes and pH were also maintained in the final products of such treatment, with no product return and the avoidance of economic loss. This study presents a novel approach for solving the major problem of the deteriorative changes that occur in semidry luncheon sausage and similar meat products which require rejection with a huge economic loss, especially in tropical and semitropical areas of the world that have similar problems of high climatic temperatures and a low availability of energy or technological resources.

ß-Lactamase Producing Escherichia coli Encoding blaCTX-M and blaCMY Genes in Chicken Carcasses from Egypt.

Escherichia coli with multidrug resistance and ß-lactamase genes may constitute a great public health hazard due to the potential for their transmission to humans through the food chain. This study determined the prevalence, antibiotic resistance profiles, phylogroups, and ß-lactamase genes of E. coli isolates from chicken carcasses marketed in Mansoura, Egypt. Interestingly, E. coli was detected in 98% (98/100) of the chicken carcasses examined, which seemed among the highest contamination rates by E. coli worldwide. From the 425 genetically verified uidA gene-positive E. coli, 85 isolates were further studied for antimicrobial resistance profiles, phylogroups, and ß-lactamase genes. Interestingly, 89.41% of E. coli (76/85) strains tested against 24 different antibiotics were multidrug-resistant. Of the examined 85 E. coli isolates, 22 (25.88%) isolates harbored blaCTX-M and were resistant to ampicillin, cefazoline, and ceftriaxone, while three of them were resistant to ceftazidime besides. Nine (10.59%) E. coli strains harbored AmpC- ß-lactamase blaCMY and were resistant to ampicillin. One isolate co-carried blaCMY and blaCTX-M genes, though it was negative for the blaTEM gene. Of the 35 isolates that harbored either extended-spectrum ß-lactamase (ESBL) and/or AmpC ß-lactamase genes, six strains (17.14%) were assigned to pathogenic phylogroup F and one to phylogroup E, whereas 28 (80%) isolates belonged to commensal phylogenetic groups.

Paraclinical Changes Occurring in Dairy Cows with Spontaneous Subacute Ruminal Acidosis under Field Conditions.

This study was undertaken to investigate the changes in the blood and milk biochemical parameters found in naturally occurring and long-lasting spontaneous subacute ruminal acidosis (SARA), with the aim of identifying the patterns of paraclinical changes and providing valuable data for more accurately identifying SARA in cows under field conditions. The study was conducted on a dairy herd with a history of the occurrence of SARA-associated clinical signs. Twelve cows, between 20 and 150 days in milk, were randomly selected and subsequently subjected to venous blood, milk, and ruminal fluid collection. The mean pH value of the ruminal fluid was 5.56 ± 0.32, and 58% (7/12) of the tested cows were SARA positive (ruminal pH ≤ 5.5). The albumin, calcium, and phosphorus serum concentration values were significantly lower (p < 0.05) in the SARA group than in the group of healthy cows. Serum aspartate aminotransferase (AST) and glutamate dehydrogenase (GLDH) activity were significantly higher in the SARA cows (p < 0.05) than in the group of healthy cows. The mean values of milk fat, milk protein content, and milk fat-to-protein ratio were significantly lower (p < 0.05) in the tested cows of the SARA group than in the healthy group of cows. In conclusion, the results of the current study indicate that long-term SARA triggered by a high-concentrate diet is associated with clinically significant changes in both the blood composition (hypoalbuminemia, hypocalcemia, and increased serum AST and GLDH activity) and the milk composition (decreased fat and protein percentage and milk fat-to-protein ratio). Altogether, the obtained results provide a more reliable pattern of paraclinical changes and useful insights for detecting SARA in dairy cows under field conditions.

Green Synthesis of Gold Nanoflowers Using Rosmarinus officinalis and Helichrysum italicum Extracts: Comparative Studies of Their Antimicrobial and Antibiofilm Activities.

This study was concerned with the green synthesis of gold nanoflowers (AuNFs) using the bioactive constituents of Rosmarinus officinalis (rosemary) and Helichrysum italicum (immortelle) extracts, as reducer and stabilizer agents along with the determination of their antibacterial and antibiofilm activity against E. coli, S. aureus, and S. epidermidis. The AuNFs were characterized using STEM, UV-Vis, DLS, ZETA, FESEM-EDX, and FTIR techniques. The antibacterial and antibiofilm activity of the AuNFs were evaluated by microdilution broth and microtiter plate (MTP) tests, respectively. STEM and DLS analysis confirmed the flower-like morphology of gold nanoparticle clusters of R. officinalis-AuNFs (R-AuNFs) and H. italicum-AuNFs (H-AuNFs) with a size of 20-130 nm and 15-90 nm, respectively. The MICs of R-AuNFs were found to be 40 µg/mL for E. coli and S. epidermidis and 160 µg/mL for S. aureus. The MICs of H-AuNFs against all bacterial strains were 20 µg/mL. All tested AuNFs exhibited a strong dose-dependent antibiofilm activity against the test strains, and H-AuNFs was more effective than R-AuNFs. The green synthesis of AuNFs from the rosemary and immortelle extracts can be applied as a potential agent to overcome the growth of biofilm-producing microorganisms in food industries.

Improving the Structural Changes, Electrophoretic Pattern, and Quality Attributes of Spent Hen Meat Patties by Using Kiwi and Pineapple Extracts.

Spent broiler hen meat is sold at a lower price, owing to its poor texture and lower acceptability, in comparison with broiler meat. The tenderization of spent hen meat using kiwi and pineapple extracts will encourage meat processors to use this less expensive meat as a new source of raw materials for the production of different chicken meat-derived products, particularly when solving the problem associated with a great shortage of raw chicken meat materials. Therefore, the present study was undertaken to investigate the effect of kiwi extracts (5 and 7%), pineapple extracts (5 and 7%), and a combination between the two (5% kiwi and 5% pineapple) on the structural changes, electrophoretic pattern, and quality attributes of spent hen meat patties. The results demonstrated that all extract-treated meat patties exhibited a significant decrease in collagen content and shear force value, a significant increase in collagen solubility percentage, and significant improvements to all sensory attributes, in contrast to their counterpart control samples. Additionally, a non-significant change in lightness and yellowness values and a significant increase in redness value were observed in all extract-treated specimens. Moreover, the treatment of spent hen meat patties with kiwi and pineapple extracts resulted in marked degenerative changes of the muscle fiber and connective tissue, as well as a decrease in protein bands, with subsequent enhancement in tenderness. The effect was more highlighted in specimens treated with pineapple extracts (7%) and with kiwi (5%) and pineapple extracts mixture (5%).

Structural Changes, Electrophoretic Pattern, and Quality Attributes of Camel Meat Treated with Fresh Ginger Extract and Papain Powder.

Camel is a valuable source of meat for African and Asian countries; however, the most important problem associated with camel meat is its extreme toughness. This toughness has been attributed to its contents of connective tissue, which become more crossly linked in old animals. The toughness of camel meat decreases the consumer acceptance of this meat and reduces its chances of being utilized as a raw material for further processing into meat products. Ginger and papain were used in the current study as tenderizing enzymes, and the structural changes, electrophoretic pattern, physicochemical characteristics, and sensory scores of the treated meat were examined. The treatment of camel meat with ginger and papain resulted in marked destructive changes in the connective tissue and myofibers, and a reduction in the protein bands, with a consequent improvement in its tenderness. All the enzyme-treated samples exhibited significant increases in the protein solubility, with significant decreases in the shear-force values. Moreover, an improvement in the sensory scores of the raw and cooked meat and a reduction in the bacterial counts after the treatments were recorded. Ginger and papain induced a significant improvement in the physicochemical characteristics, sensory attributes, and bacterial counts of the camel meat; therefore, these materials can be utilized by meat processors to boost the consumer acceptance of this meat, and to increase its suitability as a raw material for further meat processing.

An Overview of Biofilm Formation-Combating Strategies and Mechanisms of Action of Antibiofilm Agents.

Biofilm formation on surfaces via microbial colonization causes infections and has become a major health issue globally. The biofilm lifestyle provides resistance to environmental stresses and antimicrobial therapies. Biofilms can cause several chronic conditions, and effective treatment has become a challenge due to increased antimicrobial resistance. Antibiotics available for treating biofilm-associated infections are generally not very effective and require high doses that may cause toxicity in the host. Therefore, it is essential to study and develop efficient anti-biofilm strategies that can significantly reduce the rate of biofilm-associated healthcare problems. In this context, some effective combating strategies with potential anti-biofilm agents, including plant extracts, peptides, enzymes, lantibiotics, chelating agents, biosurfactants, polysaccharides, organic, inorganic, and metal nanoparticles, etc., have been reviewed to overcome biofilm-associated healthcare problems. From their extensive literature survey, it can be concluded that these molecules with considerable structural alterations might be applied to the treatment of biofilm-associated infections, by evaluating their significant delivery to the target site of the host. To design effective anti-biofilm molecules, it must be assured that the minimum inhibitory concentrations of these anti-biofilm compounds can eradicate biofilm-associated infections without causing toxic effects at a significant rate.

The physicochemical and microbiological quality of meat produced in a traditional slaughterhouse in Mansoura City, Egypt.

INTRODUCTION: In several developing countries the slaughter of meat producing animals is still practiced in traditional slaughterhouses. In the Mansoura slaughterhouse, animals are subjected to various stressors and treated with cruelty, in addition to unhygienic treatment and handling of animal carcasses. Hence, this study was designed to investigate the meat quality from cattle, buffalo, and sheep carcasses processed in an old-fashioned slaughterhouse from Mansoura city, Egypt, in the context of pre-slaughter stress. METHODOLOGY: The bleeding efficiency and the ultimate pH (pHu) of carcasses were tested, along with the effect of post-slaughter handling practice on the microbiological properties of meat. RESULTS: From the 351 examined animals, the ultimate pH (pHu) was less than 5.8 in 81 cases (23.1%) and higher than 6.0 in 165 cases (47%). Furthermore, 45 (12.8%), 270 (76.9%), and 36 (10.3%) of the tested carcasses were well-, moderate- and imperfectly-bled, respectively. Cultivation using the wet-dry triple swab technique sampled from the outer surfaces of cattle, buffalo, and sheep carcasses revealed that about 47.9% of the tested carcasses were contaminated, with total viable count levels exceeding 7 log10 cfu/cm2, and 42.7% were contaminated with Enterobacteriaceae, with levels > 3 log10 cfu/cm2. The molds and yeasts from the tested carcasses had lower counts (< 2 log10 cfu/cm2). CONCLUSIONS: Results indicated neglect in terms of sanitary measures during slaughtering and dressing of carcasses, with subsequent higher microbial contamination and impaired meat quality. Therefore, the traditional slaughtering facilities should be modernized to increase their meat producing efficiency, subsequently leading to exportation possibilities.