Search Results (130)

Ethylene is a multifunctional phytohormone that regulates plant growth, development, and responses to abiotic/biotic stresses. RTE1 (Reversion-To-Ethylene Sensitivity1) acts as a negative regulator of the ethylene responses in Arabidopsis by positively regulating ethylene receptor ETR1. However, the role of RTE genes in sweet potato (Ipomoea batatas), an import food crop worldwide, remains largely unknown, particularly their involvement in abiotic stress adaptation. In this study, we identified 23 RTE genes in sweet potato, distributed across 21 chromosomes and one scaffold BrgTig00017944. The phylogenetic analysis divided them into two groups, the RTE1 group and RTH (RTE1-Homolog) group. Synteny analysis revealed that whole genome duplication (WGD) was the major force of expansion of the IbRTE gene family. Multiple cis-acting elements responsive to hormones and stress were found in the promoter region of IbRTE genes. The transcriptome expression profiling showed that the majority of IbRTEs have tissue-specific and differential expression under drought and salt stresses. Meanwhile, the qRT–PCR results showed that the 14 representatives IbRTEs have differential expression profilings under salt (NaCl) and drought (PEG) treatments. These findings suggest that the IbRTE genes may be involved in sweet potato’s adaptive responses to salt and drought, providing a valuable foundation for further functional studies. Full article

Ready-to-eat (RTE) sandwiches are consumed globally due to their convenience, availability, and affordability. Sandwich processing practices and their ingredients expose the sandwiches to various sources of contamination, which can enhance their microbial diversity and introduce certain pathogenic and spoilage bacteria, thereby affecting their safety and quality. Sandwiches may not receive safe cooking temperatures sufficient to destroy food poisoning bacteria, as they are often cooked and served quickly to meet high consumer demand. Improper storage temperatures can enhance microbial growth, and frequent improper handling makes this food a good vehicle for various pathogens such as Escherichia coli, Listeria monocytogenes, Salmonella spp., Staphylococcus aureus, and norovirus. Many pathogenic sandwich-associated bacteria, such as L. monocytogenes, showed resistance to clinically important antibiotics. Sandwich microbiota have been investigated; however, their diversity, antimicrobial resistance, and importance to sandwich safety and quality have been rarely reviewed. Therefore, this review elucidates the diversity of sandwich microbiota as an impact of ingredients, handling practices, and storage, with emphasis on the importance of this diversity on sandwich safety and quality. It also discusses strategies, control measures, and recommendations to reduce the risk of contamination of sandwiches with pathogenic bacteria or their antibiotic resistance genes, thereby safeguarding public health. Full article

Foodborne pathogens remain a global public health concern, and antimicrobial resistance increases their impact. In mass-gathering cities such as Al-Madinah Al-Munawarah, contaminated ready-to-eat (RTE) fast foods can contribute to both local transmission and international spread. In this study, 300 RTE fast food samples, including shawarma, burgers, fried chicken, sandwiches, and salads, were collected from international franchises, local restaurants, and street vendors. Pathogens were identified using conventional culture combined with matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Antimicrobial susceptibility testing followed CLSI guidelines, and real-time PCR confirmed species identity and screened resistance determinants. Principal component analysis (PCA) and dendrogram clustering were used to assess diagnostic discrimination. Among the 300 samples, 129 (43.0%) were culture positive. The most common pathogens were Staphylococcus aureus (14.3%) and Escherichia coli (13.0%), followed by Salmonella spp. (9.0%) and Acinetobacter baumannii (6.7%). About 35% of S. aureus isolates were methicillin resistant (MRSA), and 85% of A. baumannii carried OXA-type carbapenemase genes. MALDI-TOF MS achieved 96.1% score-based identification and, with PCA, showed strong interspecies separation. PCR confirmed species identity and detected widespread resistance genes, with genotype–phenotype concordance of at least 80%. Overall, 60.5% of isolates were multidrug resistant. RTE fast foods in Al-Madinah represent reservoirs of MDR pathogens, including carbapenemase-producing A. baumannii. The combined use of MALDI-TOF MS and real-time PCR established a rapid and scalable workflow that provided reliable identification and resistance profiling in less than 24 h, compared with 48 to 72 h for conventional methods. This approach supports One Health surveillance in high-risk food settings and strengthens preparedness for mass gatherings. Full article

What people consume for breakfast and why they do so have not been widely studied, especially in developing-economy countries. This study aimed to determine the breakfast food habits and their drivers of adults in South Africa, a multiethnic middle-income country. An online cross-sectional survey was conducted among 1000 representative consumers of moderate to higher living standard (Living Standard Measure [LSM] range ≥ 5). Data from 842 respondents (mean age 41 years, 51.7% females and 48.3% males) was analyzed. Of 21 different food types in descending order, the most frequently consumed were bread, ready-to-eat (RTE) cereals, fruits/nuts, high-fibre cereal, yoghurt, and leftovers, all consumed weekly by 42–65% of respondents. Principal component analysis revealed that three components had eigenvalues > 1 characterized as “On-the-go”, “Traditional”, and “Ready-to-eat and functional cereals”. They explained 49% of the data. Decision tree analysis revealed that, for example, Black respondents were more likely to consume foods in the “traditional” category. Quick-and-easy options, notably bread, RTE cereals, fruits/nuts, and leftovers, were dominant, especially among lower LSM respondents. Tasty and filling, and value for money, as exemplified by leftovers and vetkoek (fried dough), were important considerations, particularly among these respondents. These drivers can lead to unhealthy choices, a major concern in South Africa with its high level of diet-related diseases. This study, however, indicates that South African consumers, irrespective of age, ethnicity, and living standard, rated healthfulness and nutritional value highly as a benefit, the highest for choosing 13 of the 21 foods. Additionally, aspects of wellness, e.g., feeling energized/recharged, rated very highly. Thus, it is concluded that the opportunity exists to support consumer needs of nutrition and wellness together with affordability, taste, and satiety. Full article

Listeria monocytogenes is a major foodborne pathogen associated with increasing global public health concern due to numerous outbreaks. Rapid pathogen detection is critical for reducing both the incidence and severity of foodborne illnesses. Recent advances in nanotechnology are transforming analytical methods, particularly for detecting foodborne pathogens. Magnetic nanoparticles (MNPs) and gold nanoparticles (GNPs) are among the most widely used nanomaterials in this field. This study investigated the potential use of MNPs and GNPs for the rapid and specific isolation of L. monocytogenes from fresh salad, deli meat, and frozen vegetables. L. monocytogenes (ATCC 19117) served as the model organism for biosensing and target capture. Results showed that the limits of detection (LoDs) for the GNP-based plasmonic/colorimetric biosensor and the MNP-based biosensor were 2.5 ng/µL DNA and 1.5 CFU/mL, respectively. Both GNPs and MNPs specifically detected L. monocytogenes even in the presence of closely related pathogens. Integration of MNPs and GNPs significantly enhanced the sensitivity of L. monocytogenes detection. Within one hour, naturally contaminated pre-packaged salad samples demonstrated clear evidence of effective direct capture by MNPs and specific identification by GNPs. This combined approach enables rapid and accurate on-site detection of L. monocytogenes, facilitating timely intervention and reducing the risk of contaminated foods reaching consumers. Full article

Listeria monocytogenes is a significant foodborne pathogen associated with high rates of hospitalization and death, especially among vulnerable populations. Despite established regulatory standards and available antimicrobial intervention strategies, L. monocytogenes remains as a pathogen of concern in ready-to-eat (RTE) foods. This ultimately can lead to food recalls or listeriosis outbreak, highlighting its ongoing risks to food safety and public health. This review consolidates publicly accessible surveillance case counts and recall data of L. monocytogenes contamination from Australia, Europe, Canada, and the United States to assess the contamination trends in the RTE food supply chain. It also evaluates the effectiveness of antimicrobial intervention strategies, including both those currently implemented in industry and those that have been studied as potential interventions but are not yet widely adopted. Key factors affecting the efficiency of those strategies are identified, including food matrix composition, water activity (a_w), fat content, and strain variability. Emerging multi-hurdle technology that integrates physical, chemical, and biological antimicrobial interventions are highlighted as promising approaches for maintaining both food safety and product quality. It also outlines the role of quantitative microbial risk assessment (QMRA) as a decision-support tool to select appropriate control strategies, predict recall risk and guide evidence-based risk management. Future research directions are proposed to expand the application of QMRA in managing recall risks throughout the RTE food supply chain due to L. monocytogenes. Full article

Ready-to-eat (RTE) foods can carry antimicrobial-resistant pathogens; however, few studies link real-world surveillance to practical interventions. This study addressed this gap by estimating the prevalence of Staphylococcus aureus (S. aureus) and methicillin-resistant S. aureus (MRSA) in ready-to-eat foods from Al-Qassim and evaluating a rapid, orthogonal confirmation workflow (culture → MALDI-TOF MS → Vitek 2 → mecA/mecC PCR). The in vitro activity of citrate-stabilized silver nanoparticles (AgNPs) against food-derived MRSA was quantified, and synergy with oxacillin (primary) and ciprofloxacin (secondary) was examined. Silver-susceptibility stability was assessed over 20 days of sub-MIC serial passage, with attention to whether β-lactam co-exposure constrained drift. We surveyed 149 RTE products and paired the confirmation workflow with mechanistic tests of AgNPs as antibiotic adjuvants. S. aureus was recovered from 24.2% of products and MRSA from 6.7%, with higher recovery from animal-source matrices and street-vendor outlets. MALDI-TOF MS provided rapid species confirmation and revealed two reproducible low-mass peaks (m/z 3990 and 4125) associated with MRSA, supporting spectral triage pending molecular confirmation. Antimicrobial susceptibility testing showed the expected β-lactam split (MRSA oxacillin/cefoxitin non-susceptible; MSSA oxacillin-susceptible but largely penicillin-resistant), with last-line agents retained. Citrate-stabilized AgNPs displayed consistent potency against food-derived MRSA (MIC 8–32 µg/mL; MIC₅₀ 16; MIC₉₀ 32) and were predominantly bactericidal (MBC/MIC ≤ 4 in 90%). Checkerboards demonstrated frequent AgNP–oxacillin synergy (median fractional inhibitory concentration index [FICI] 0.37; 4–16-fold oxacillin MIC reductions) and additive-to-synergistic effects with ciprofloxacin (median FICI 0.63), translating time–kill assays into rapid, sustained bactericidal activity without antagonism. During sub-MIC evolution, silver MICs rose modestly (median two-fold) and often regressed off drug; oxacillin co-exposure limited drift. RTE foods therefore represent credible MRSA exposure routes. Integrating MALDI-assisted triage with automated AST enables scalable surveillance, and standardized AgNP formulations emerge as promising β-lactam adjuvants—pending in situ efficacy, safety, and residue evaluation. Full article

Fresh-cut fruit salads (fruit cocktails) are marketed as a convenient food item with a limited shelf-life (4 days at 4 °C). Given rising electricity prices, increased cooling temperature during production, transport, and retail from 4 °C to 8 °C and extended shelf-life from four to eight days without compromising food safety are discussed. This study investigates the proliferation of Listeria monocytogenes in ready-to-eat (RTE) fresh-cut fruit cocktails at three temperature regimes. The fruit cocktail, consisting of pineapple, red apples, cantaloupe, and red grapes, was inoculated with a clinical strain of L. monocytogenes (SLV 444; CCUG 69007) and stored at 4 °C, 8 °C, or a dynamic temperature regime (4 °C for one day, 8 °C for seven days). After four-day storage at 4 °C, growth of L. monocytogenes was not supported. Despite the fruit cocktail’s pH below the minimum requirements of the target organism, all other treatments supported growth of L. monocytogenes, but below the legal limit of 2 log CFU + 1 g⁻¹ per fruit cocktail. There is an increased risk of exceeding the microbiological safety end product criteria, especially at 8 °C or dynamic storage temperatures, if seemingly insignificant Listeria contamination is present in or on fruit cocktail ingredients. Full article

Background/Objectives: As convenience store meals become a major dietary source for modern society, the reliability of their nutrition labels is increasingly scrutinized. With advances in artificial intelligence (AI), large language models (LLMs) have been explored for automated nutrition estimation. Aim: To evaluate the accuracy and clinical applicability of AI-assessed nutrition data by comparing outputs from five AI models with professional dietitian estimations and labeled nutrition facts. Methods: Eight ready-to-eat convenience store meals were analyzed. Four experienced dietitians independently estimated the meals’ calories, macronutrients, and sodium content based on measured food weights. Five AI chatbots were queried multiple times with identical input prompts to assess intra- and inter-assay variability. All results were compared to the official nutrition labels to quantify discrepancies and cross-model consistency. Results: Dietitian estimations showed strong internal consistency (CV < 15%), except for fat, saturated fat and sodium (CVs up to 33.3 ± 37.6%, 24.5 ± 11.7%, and 40.2 ± 30.3%, respectively). Among AI models, ChatGPT4.o showed relatively consistent calory, protein, fat, saturated fat and carbohydrate estimates (CV < 15%), and Claude3.7, Grok3, Gemini, and Copilot showed caloric and protein content as consistent (CV < 15%). Sodium values were consistently underestimated across all AI models, with CVs ranging from 20% to 70%. The accuracy of nutritional fact estimation over the five AI models for calories, protein, fat, saturated fat and carbohydrates was between 70 and 90%; when compared to the nutritional labels of RTE, the sodium content and saturated fat estimated were severely underestimated. Conclusions: Current AI chat models provide rapid estimates for basic nutrients and can aid public education or preliminary assessment; GPT-4 outperforms peers in calorie and potassium-related estimations but remains suboptimal in micronutrient prediction. Professional dietitian oversight remains essential for safe and personalized dietary planning. Full article

Ready-to-eat (RTE) foods including sandwiches, pastries, shawarma, and burgers are widely consumed and may potentially increase the risk of foodborne infections. This study investigated the prevalence, serovar diversity, and antimicrobial resistance (AMR) of Salmonella spp. in RTE foods collected between January and June 2024 from street vendors and restaurants across Erbil, Iraq. A total of 350, including 85 sandwiches, 75 pastries, 95 shawarma, and 95 burgers obtained from 115 cafeteria, 120 street vendors, and 115 restaurants were analyzed. Salmonella was detected in 7.1% (n = 25) of samples, with a high contamination in shawarma (8.4%; n = 95), followed by sandwiches (7.1%; n = 85), pastries (6.7%; n = 75), and burgers (6.3%; n = 95). Street vendors exhibited a higher (9.2%; n = 120) contamination rate compared to the cafeteria (6.9%; n = 115) and restaurants (5.2%; n = 115). Among 25 Salmonella isolates, 10 serotypes were identified, with S. Anatum (20%) and S. Typhimurium (16%) being the most prevalent. All isolates were susceptible to colistin, cefadroxil, and gentamicin, while showing high resistance to streptomycin (52%) and levofloxacin (48%). Contamination peaked during the warmer months, particularly in June (15.4%) and May (11.5%), when compared to the other sampling months. These findings highlight significant food safety concerns related to Salmonella contamination and AMR in RTE foods, emphasizing the urgent need for enhanced hygiene practices and regulatory oversight especially among street vendors. Full article

Listeria monocytogenes (Lm) is a serious public health foodborne pathogen cause of listeriosis, usually in elderly, pregnant and immunocompromised people, linked to consumption of contaminated food, especially ready-to-eat (RTE) products. Different protocols can be used to detect Lm, and ISO11290-1:2017 is the reference method in Europe. Through molecular techniques such as whole genome sequencing (WGS) it is possible to discriminate between Lm strains, which are unequally distributed between clinical cases, food or food related environments, probably also due to enrichment step bias towards some Lm serogroup (IIa) compared to IVb. In the present work a set of Lm strains, detected in clinical cases and food, was investigated to define Lm strains growth ability after incubation in Half Fraser broth, and Genome Wide Association Studies (GWAS) applied to correlate the growth phenotype traits to presence of relevant genes. GWAS enabled the identification of a more relevant cassette of genes associated to a holin region of bacteriophage A118 and the determination of the distribution of relevant genes, highlighted from GWAS analysis within a population of Lm IVb and IIa. Full article

Background: Grain foods are important sources of complex carbohydrates, fiber, vitamins, and minerals. Objective: To identify healthy grain foods and to assess their associations with composite diet quality measures and selected health outcomes. Methods: Healthy grain foods were identified using two methods. The first one, Carbohydrate Food Quality Score (CFQS-3) was based on whole grains, fiber, and added sugar. The second, NRF9.3g score for grains, balanced nutrients to encourage (protein, fiber, vitamins B1, B2, B3, and E, folate, iron, and magnesium) against added sugar, sodium, and saturated fat. Nutrient composition data for 1244 grain foods came from the USDA Food and Nutrient Database for Dietary Studies (FNDDS 2017–2023). Dietary intakes came from the National Health and Nutrition Examination Surveys (NHANES 2017–2023). The Healthy Eating Index (HEI 2020) and the diet-level Nutrient Rich Food Index (NRF) were the two measures of diet quality. National food prices came from the USDA 2021 Thrifty Food Plan. Data on body weight, waist circumference, insulin, and cholesterol came from NHANES clinical files. Results: Healthy grain foods were those that scored >2 points on CFQS-3 or were in the top tertile of NRF9.3g scores. The CFQS-3 score favored cooked whole grains and cereals and savory snacks. The NRF9.3g score gave the highest ratings to breads, rolls, and RTE cereals. Consumers of healthy grains identified using both methods had higher HEI 2020 values and higher diet-level NRF scores. Both effects were dose-dependent. Consumption of healthy grains was associated with lower obesity rates and lower fasting insulin levels. Conclusions: Consumption of healthy grain foods was associated with healthier diets and lower obesity prevalence. Dietary guidelines need to acknowledge the contribution of healthy grain foods to diet quality and health. Full article

Introduction: Staphylococcus aureus is a high-priority foodborne pathogen contributing to several food poisoning outbreaks. Methicillin- and vancomycin-resistant S. aureus (MRSA and VRSA), pose significant public health concerns due to their potential for serious illness, antibiotic resistance, and transmission within both healthcare and community settings. These bacteria can cause numerous infections, ranging from skin and soft tissue infections to life-threatening conditions like bloodstream infections, pneumonia, and endocarditis. Although several publications are concerned with Staphylococcus aureus contamination in ready-to-eat (RTE) food products, little published data is available about its prevalence in pizza, which is widely distributed and consumed worldwide. Methods: The current study is intended to determine the prevalence, virulence genes, and antimicrobial resistance profiles of S. aureus in three hundred ready-to-eat pizza samples (100 each of meat, chicken, and canned tuna pizzas) collected from different restaurants in Mansoura City, Egypt. The typical colonies on Baird–Parker selective agar supplemented with egg yolk tellurite emulsion were counted and further confirmed based on Gram staining, coagulase testing, catalase testing, carbohydrate fermentation, and thermostable nuclease production. The genomic DNA of the confirmed coagulase-positive isolates was prepared and subjected to PCR analyses for detecting the nuc gene, mecA (methicillin resistance gene), and vancomycin resistance gene (vanA), as well as six selected S. aureus virulence genes: sea, seb, sec, sed, hla, and tsst. The antimicrobial resistance profile of the S. aureus isolates was determined against 16 antimicrobial agents belonging to six classes using the agar disc diffusion method according to the Clinical and Laboratory Standards Institute guidelines (CLSI), except for oxacillin and vancomycin, which were assessed using the MIC test. Results: The results revealed that 56% (56/100), 56% (56/100), and 40% (40/100) of chicken, meat, and canned tuna pizzas were positive for S. aureus, with an overall prevalence of 50.7% (152/300). All 560 isolates (100%) were verified as S. aureus based on molecular confirmation of the nuc gene. Interestingly, 48.6% (272/560) and 8.6% (48/560) of the isolates tested were identified as methicillin- and vancomycin-resistant S. aureus (MRSA and VRSA) through detection of mecA and vanA genes, respectively. Among the S. aureus isolates tested, the hla gene was detected in 87.1% (488/560), while the enterotoxin genes sea, seb, sec, and sed were identified in 50% (280/560), 78.6% (440/560), 9.8% (55/560), and 24.5% (137/560) of isolates, respectively. All recovered isolates (n = 560) were classified as multidrug-resistant and were resistant to penicillin, oxacillin, and ampicillin. Moreover, 77% (431/560), 24% (134/560), 8% (45/560), and 8.6% (48/560) of isolates were resistant to cefotaxime, ciprofloxacin, azithromycin, and vancomycin, respectively. Conclusions: The current study emphasizes that ready-to-eat pizza is highly contaminated with multidrug-resistant S. aureus, highlighting the urgent need for rationalizing antibiotic use in both veterinary and human medicine to prevent the transmission of resistant bacteria through the food chain. Additionally, strict adherence to good hygienic practices throughout all stages of the food chain is essential to minimize overall contamination and enhance food safety. Full article

Antimicrobial Resistance (AMR), i.e., the evolution of microbes to become resistant to chemicals used to control them, is a global public health concern that can make bacterial diseases untreatable. Inputs including antibiotics, metals, and biocides can create an environment in the agrifood chain that selects for AMR. Consumption of food represents a potential exposure route to AMR microbes and AMR genes (ARGs), which may be present in viable bacteria or on free DNA. Ready-to-eat (RTE) foods are of particular interest because they are eaten without further cooking, so AMR bacteria or ARGs that are present may be consumed intact. They also represent varied production systems (fresh produce, cooked meat, dairy, etc.). An evidence gap exists regarding the diversity and consumption of ARGs in RTE food, which this study begins to address. We sampled 1001 RTE products at retail sale in the UK, in proportion to their consumption by the UK population, using National Diet and Nutrition Survey data. Bacterial DNA content of sample extracts was assessed by 16S metabarcoding, and 256 samples were selected for metagenomic sequencing for identification of ARGs based on consumption and likely bacterial DNA content. A total of 477 unique ARGs were identified in the samples, including ARGs that may be involved in resistance to important antibiotics, such as colistin, fluoroquinolones, and carbapenems, although phenotypic AMR was not measured. Based on the incidence of ARGs in food types, ARGs are estimated to be present in a high proportion of average diets. ARGs were detected on almost all RTE food types tested (48 of 52), and some efflux pump genes are consumed in 97% of UK diets. Full article

With increasing popularity of food delivery services, the microbial safety of transported meals should be ensured. An effect of the type of a meal (cooked rice; mashed potatoes; mushroom sauce), inner primary packaging (sugarcane bagasse [SB] tray; polypropylene [PP] tray), secondary container (polyester/polyethylene foam/aluminum foil [PPA] bag; PP box) on the time interval of the internal hot ready-to-eat (RTE) meal temperature decrease to the value critical for Bacillus cereus growth (40 °C) was tested during a simulated delivery; in aliquot samples of the same meals, B. cereus growth was quantified presuming a natural contamination of the meals. Type of a meal had no effect on the tested time interval (p > 0.05). Packaging a meal in the PP tray as compared to the SB tray and inserting primary trays into the PP box instead of PPA bag delayed (p < 0.05) the internal meal temperature decrease by 50 and 15 min, respectively. Average B. cereus counts in the naturally contaminated meals after the four-hour culturing at 40 °C was 2.99 log CFU·g⁻¹. It was concluded that a hot RTE meal delivered up to four hours under the tested conditions is not likely to facilitate B. cereus growth above unacceptable levels. Full article