Coli O157 Research Articles

Biological Control of Escherichia coli O157:H7 in Dairy Manure-Based Compost Using Competitive Exclusion Microorganisms.

Animal manure-based compost is a valuable organic fertilizer and biological soil amendment. To ensure the microbiological safety of compost products, the effectiveness of competitive exclusion microorganisms (CE) in reducing Escherichia coli O157:H7 in dairy manure-based compost was evaluated. A cocktail of E. coli O157:H7 strains were inoculated into dairy compost along with CE strains isolated from compost, and the reduction in E. coli O157:H7 by CE was determined in compost with 20%, 30%, and 40% moisture levels at 22 °C and 30 °C under laboratory conditions, as well as in fall, winter, and summer seasons under greenhouse settings. Under lab conditions, CE addition resulted in 1.1-3.36 log reductions in E. coli O157:H7 in compost, with enhanced pathogen reduction by higher moisture and lower temperature. In the greenhouse, >99% of the E. coli O157:H7 population in compost with ≥30% moisture due to cross-contamination can be effectively inactivated by CE within 2 days during colder seasons. However, it took ≥8 days to achieve the same level of reduction for heat-adapted E. coli O157:H7 cells. Our results demonstrated that the competitive exclusion of microorganisms can be an effective tool for controlling foodborne pathogens in compost and reducing the potential for soil and crop contamination.

Determining the prevalence of Escherichia coli, Salmonella, and shiga toxin-producing Escherichia coli in manure of dairy lagoons.

The aim of this study was to determine the prevalence of microbial pathogens in manure of dairy lagoons in California. To determine pathogens in dairy manure stored in anaerobic lagoons of dairy farm, an extensive field study was conducted across California to sample manure from 20 dairy farms. Samples were analyzed to determine the prevalence of indicator Escherichia coli, Shiga toxin producing E. coli (STEC), Salmonella, and E. coli O157: H7. To test the E. coli, STEC, and Salmonella, we used agar culture-based method followed by polymerase chain reaction (PCR) method. In addition, a real- time PCR based method was used to determine the presence of E coli O157: H7. Study demonstrated that the prevalence of Salmonella in manure sample is lower than E. coli. The presence of Salmonella was found in 2.26% of the samples, and both the culture-based and PCR methods yielded comparable outcomes in detecting Salmonella. Moreover, ∼11.30% of the total samples out of the 177 were identified as positive for STEC by qPCR. These findings demonstrate that indicator E. coli are abundantly present in anaerobic lagoons. However, the presence of STEC, and Salmonella is substantially low.

"Cave Effect" Induces Self-Assembled Bimetallic Hollow Structure for Three-in-One Lateral Flow Immunoassay.

Bimetallic hollow structures have attracted much attention due to their unique properties, but they still face the problems of nonuniform alloys and excessive etching leading to structural collapse. Here, uniform bimetallic hollow nanospheres are constructed by pore engineering and then highly loaded with hemin (Hemin@MOF). Interestingly, in the presence of polydopamine (PDA), the competitive coordination between anionic polymer (γ-PGA) and dimethylimidazole does not lead to the collapse of the external framework but self-assembly into a hollow structure. By constructing the Hemin@MOF immune platform and using E. coli O157:H7 as the detection object, we find that the visual detection limits can reach 10, 3, and 3 CFU/mL in colorimetric, photothermal, and catalytic modes, which is 4 orders of magnitude lower than the traditional gold standard. This study provides a new idea for the morphological modification of the metal-organic skeleton and multifunctional immunochromatography detection.

A Dual-mode platform for the rapid detection of Escherichia coli O157:H7 based on CRISPR/Cas12a and RPA.

Escherichia coli O157:H7 (E. coli O157:H7) is a foodborne pathogenic microorganism that is commonly found in the environment and poses a significant threat to human health, public safety, and economic stability worldwide. Thus, early detection is essential for E. coli O157:H7 control. In recent years, a series of E. coli O157:H7 detection methods have been developed, but the sensitivity and portability of the methods still need improvement. Therefore, in this study, a rapid and efficient testing platform based on theCRISPR/Cas12a cleavage reaction was constructed. Through the integration of recombinant polymerase amplification and lateral flow chromatography, we established a dual-interpretation-mode detection platform based on CRISPR/Cas12a-derived fluorescence and lateral flow chromatography for the detection of E. coli O157:H7. For the fluorescence detection method, the limits of detection (LODs) of genomic DNA and E. coli O157:H7 were 1.8fg/µL and 2.4CFU/mL, respectively, within 40min. Conversely, for the lateral flow detection method, LODs of 1.8fg/µL and 2.4 × 102CFU/mL were achieved for genomic DNA and E. coli O157:H7, respectively, within 45min. This detection strategy offered higher sensitivity and lower equipment requirements than industry standards. In conclusion, the established platform showed excellent specificity and strong universality. Modifying the target gene and its primers can broaden the platform's applicability to detect various other foodborne pathogens.

Green-Synthesized Amino Carbons for Impedimetric Biosensing of E. coli O157:H7.

This study describes the synthesis of amino-functionalized carbon nanoparticles derived from biopolymer chitosan using green synthesis and its application toward ultrasensitive electrochemical immunosensor of highly virulent Escherichia coli O157:H7 (E. coli O157:H7). The inherent advantage of high surface-to-volume ratio and enhanced rate transfer kinetics of nanoparticles is leveraged to push the limit of detection (LOD), without compromising on the selectivity. The prepared carbon nanoparticles were systematically characterized by employing CO2-thermal programmed desorption (CO2-TPD), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), ultraviolet-visible (UV-visible), and transmission electron microscopy (TEM). The estimated limit of detection of 0.74 CFU/mL and a sensitivity of 5.7 ((ΔRct/Rct)/(CFU/mL))/cm2 in the electrochemical impedance spectroscopy (EIS) affirm the utility of the sensor. The proposed biosensor displayed remarkable selectivity against interfering species, making it well suited for real-time applications. Moreover, the chitosan-derived semiconducting amino-functionalized carbon shows excellent sensitivity in a comparative analysis compared to highly conducting amine-functionalized carbon synthesized via chemical modification, demonstrating its vast potential as an E. coli sensor.

Foodborne Illnesses from Leafy Greens in the United States: Attribution, Burden, and Cost

Leafy green vegetables are a major source of foodborne illnesses. Nevertheless, few studies have attempted to estimate attribution and burden of illness estimates for leafy greens. This study combines results from three outbreak-based attribution models with illness incidence and economic cost models to develop comprehensive pathogen-specific burden estimates for leafy greens and their subcategories in the United States. We find that up to 9.18% (90% CI: 5.81%-15.18%) of foodborne illnesses linked to identified pathogens are attributed to leafy greens. Including ‘Unknown’ illnesses not linked to specific pathogens, leafy greens account for as many as 2,307,558 (90% CI: 1,077,815–4,075,642) illnesses annually in the United States. The economic cost of these illnesses is estimated to be up to $5.278 billion (90% CI: $3.230-$8.221 billion) annually. Excluding the pathogens with small outbreak sizes, Norovirus, Shiga toxin-producingEscherichia coli (both non-O157 and O157:H7), Campylobacter spp., and nontyphoidal Salmonella, are associated with the highest number of illnesses and greatest costs from leafy greens. While lettuce (romaine, iceberg, “other lettuce”) takes 60.8% of leafy green outbreaks, it accounts for up to 75.7% of leafy green foodborne illnesses and 70% of costs. Finally, we highlighted that 19.8% of Shiga toxin-producingEscherichia coli O157:H7 illnesses are associated with romaine among all food commodities, resulting in 12,496 estimated illnesses and $324.64 million annually in the United States.

Investigation antibacterial application and mechanism of the cyclodextrin-metal-organic framework loaded with gold nanoparticle

ABSTRACT The severe threat of microbial contamination to human life and health safety necessitates urgent research and development of antimicrobial materials capable of inhibiting or eradicating pathogens. Cyclodextrin metal-organic framework (CD-MOF) was utilized as a carrier to encapsulate gold nanoparticles (AuNPs), resulting in a composite material (Au@CD-MOF) that exhibited remarkable antibacterial properties. The antibacterial study revealed that Au@CD-MOF completely eradicated Staphylococcus aureus (S. aureus) and Listeria monocytogenes (L. monocytogenes) at a concentration of approximately 1 × 105 CFU/mL after 48 h and 36 h, respectively. Moreover, Au@CD-MOF also demonstrated the complete elimination of Escherichia coli O157:H7 (E. coli O157:H7), Pseudomonas aeruginosa PAO1 (P. aeruginosa PAO1), and Salmonella typhimurium (S. typhimurium) at a concentration of approximately 1 × 105 CFU/mL after 48 h. Moreover, the antibacterial mechanism of Au@CD-MOF was investigated using E. coli O157:H7 and S. aureus as model organisms. The findings revealed that Au@CD-MOF disrupted the integrity of cell membranes and diminished their potential, consequently impeding the normal functions of the bacteria. Additionally, the heightened permeability of cell membranes induced by Au@CD-MOF resulted in substantial leakage of nucleic acids and proteins, ultimately leading to bacterial eradication.

Detection of Escherichia coli O157H7 and Campylobacter jejuni in Bovine Carcasses in Two Slaughterhouses in Bio-Bío District, Chile.

Escherichia coli O157:H7 (E. coli O157:H7) and Campylobacter jejuni (C. jejuni) are pathogenic microorganisms that can cause severe clinical symptoms in humans and are associated with bovine meat consumption. Specific monitoring for E. coli O157: H7 or C. jejuni in meat is not mandatory under Chilean regulations. In this study, we analyzed 544 samples for the detection of both microorganisms, obtained from 272 bovine carcasses (280 kg average) at two slaughterhouses in the Bio-Bío District, Chile. Sampling was carried out at post-shower of carcasses and after channel passage through the cold chamber. Eleven samples were found to be positive for E. coli O157:H7 (4.0%) using microbiological and biochemical detection techniques and were subjected to a multiplex PCR to detect fliC and rfbE genes. Six samples (2.2%) were also found to be positive for the pathogenicity genes stx1, stx2, and eaeA. Twenty-two carcasses (8.0%) were found to be positive for C. jejuni using microbiological and biochemical detection techniques, but no sample with amplified mapA gene was found.

RpoS Acts as a Global Repressor of Virulence Gene Expression in Escherichia coli O104:H4 and Enteroaggregative E coli.

In 2011, in Germany, Escherichia coli O104:H4 caused the enterohemorrhagic E coli (EHEC) outbreak with the highest incidence rate of hemolytic uremic syndrome. This pathogen carries an exceptionally potent combination of EHEC- and enteroaggregative E coli (EAEC)-specific virulence factors. Here, we identified an E coli O104:H4 isolate that carried a single-nucleotide polymorphism (SNP) in the start codon (ATG > ATA) of rpoS, encoding the alternative sigma factor S. The rpoS ATG > ATA SNP was associated with enhanced EAEC-specific virulence gene expression. Deletion of rpoS in E coli O104:H4 Δstx2 and typical EAEC resulted in a similar effect. Both rpoS ATG > ATA and ΔrpoS strains exhibited stronger virulence-related phenotypes in comparison to wild type. Using promoter-reporter gene fusions, we demonstrated that wild-type RpoS repressed aggR, encoding the main regulator of EAEC virulence. In summary, our work demonstrates that RpoS acts as a global repressor of E coli O104:H4 virulence, primarily through an AggR-dependent mechanism.

A Fully Integrated Handheld Electrochemical Sensing Platform for Point-of-Care Testing of Escherichia coli O157:H7.

Fully integrated devices that enable full functioning execution without or with minimum external accessories or equipment are deemed to be one of the most desirable and ultimate objectives for modern device design and construction. Escherichia coli O157:H7 (E. coli O157:H7) is often linked to outbreaks caused by contaminated water and food. However, the sensors that are currently used for point-of-care E. coli O157:H7 (E. coli O157:H7) detection are often large and cumbersome. Herein, we demonstrate the first example of a handheld and pump-free fully integrated electrochemical sensing platform with the capability to point-of-care test E. coli O157:H7 in the actual samples of E. coli O157:H7-spiked tap water and E. coli O157:H7-spiked watermelon juice. This platform was made possible by overcoming major engineering challenges in the seamless integration of a microfluidic module for pump-free liquid sample collection and transportation, a sensing module for efficient E. coli O157:H7 testing, and an electronic module for automatically converting and wirelessly transmitting signals into a single and compact electrochemical sensing platform that retains its inimitable stand-alone, handheld, pump-free, and cost-effective feature. Although our primary emphasis in this study is on detecting E. coli O157:H7, this pump-free fully integrated handheld electrochemical sensing platform may also be used to monitor other pathogens in food and water by including specific antipathogen antibodies.

Mircrofabricating double-sided polydimethylsiloxane (PDMS) artificial phylloplane for microbial food safety research

Leafy green surface microbiology studies often experience significant variations in results due to the heterogeneous nature of leaf surfaces. To provide a precise and controllable substitute, we microfabricated double-sided artificial leafy green phylloplanes using polydimethylsiloxane (PDMS) with a vinyl-terminated polyethylene glycol chain-based hydrophobicity modifier (PDMS-PEG) to modify PDMS hydrophobicity. We further tested the properties and applications of these artificial leaves, by examining the function of epicuticular wax, growth and survival of E. coli O157:H7 87–23 on the surface, and removal of attached E. coli cells via sanitation. The double-sided PDMS-PDMS-PEG leaves well-replicated their natural counterparts in macroscopic and microscopic structure, hydrophobicity, and E. coli O157:H7 87–23 attachment. After depositing natural epicuticular wax onto artificial leaves, the leaf surface wetting ability decreased, while E. coli O157:H7 87–23 surface retention increased. The artificial leaves supplied with lettuce lysate or bacterial growth media supported E. coli O157:H7 87–23 growth and survival similarly to those on natural leaves. In the sanitation test, the artificial lettuce leaves also displayed patterns similar to those of natural leaves regarding sanitizer efficiency. Overall, this study showcased the microfabrication and applications of double-sided PDMS-PDMS-PEG leaves as a replicable and controllable platform for future leafy green food safety studies.

Determination of Virulence Factors and Antibiotic Resistance Profile of E. coli O157:H7 in some Marine and Freshwater Fish from Samsun, Türkiye

In this study, Escherichia coli O157:H7 contamination was investigated in Engraulis encrasicolus, Merlangius euxmus, Trachurus mediterraneus, Mullus barbutus, Tinca tinca, Cyprinus carpio and Oncorchynhus mykiss (total of 300 samples). The presence of certain virulence genes such as shiga toxin 1 (stx1), shiga toxin 2 (stx2), intimin (eaeA), and hemolysin (hlyA) was determined. The E-test method was employed to determine the antibiotic resistance profile and minimum inhibitory concentration (MIC) values of the isolates. Out of a total 141 freshwater fish samples, E. coli O157:H7 was detected in 5 of them (3.5%). In 159 marine fish, 2 of them (1.25%) were E. coli O157 positive. In terms of virulence characteristics, the E. coli O157:H7 isolate obtained from the Oncorhynchus mykiss sample had the stx1, eaeA, and hlyA genes. Both eaeA and hlyA genes were determined as positive in the E. coli O157 isolate identified from the Merlangius euxmus sample. Resistance to tetracycline, cefotaxime, cefepime, ciprofloxacin, gentamicin, ertapenem and cefoxitin was demonstrated in both samples. In this study, the presence of E. coli O157 in fish, detection of virulence genes and antibiotic resistance profile indicate the potential risk of infection from contaminated seafood.

Development of High-Performance and Multifunctional Nanoparticles Powered the Integrated Diagnosis and Treatment of Escherichia coli O157:H7.

Pathogenic diseases that trigger food safety remain a noteworthy concern due to substantial public health, economic, and social burdens worldwide. It is vital for developing an integrated diagnosis and treatment strategy for bacteria, which could achieve quick detection of pathogenic bacteria and the inhibition of multidrug-resistant bacteria. Herein, we reported an organic molecule (M-3) possessed strong light capture capacity, emerging a low energy gap and ΔEST. Subsequently, M-3 was integrated into a nanostructured system (BTBNPs) with excellent ROS generation, light absorption capability, and photothermal performance. Reactive oxygen species (ROS) generated by BTBNPs were mainly free radicals from a type I mechanism, and the high photothermal conversion efficiency of BTBNPs was 41.26%. Benefiting from these advantages of BTBNPs, BTBNPs could achieve a ∼99% antibacterial effect for Escherichia coli O157:H7 with 20 μM dosage and 5 min of irradiation. Furthermore, the limit of detection (LoD) of the proposed BTBNPs-LFIA (colorimetric and photothermal modalities) for detecting E. coli O157:H7 was 4105 and 419 CFU mL-1, respectively. Overall, this work is expected to provide a new and sophisticated perspective for integrated diagnosis and treatment systems regarding pathogenic bacteria.

The influence of pH on the efficacy of oxidation-reduction potential (ORP) to predict chlorine disinfection of surrogate bacteria, Escherichia coli O157:H7 and Listeria monocytogenes in oxidant demand free conditions and fresh produce wash water

Oxidation-reduction potential (ORP) is commonly used as a rapid measurement of the antimicrobial potential of free chlorine during industrial fresh produce washing. The current study tested the hypothesis that ORP can act as a “single variable” measurement of bacterial (vegetative and endospores) inactivation effectiveness with free chlorine irrespective of the water pH value. This situation has on occasion been assumed but never confirmed nor disproven. Chlorine-dosed pH 6.5 and 8.5 phosphate buffer solutions were inoculated with Escherichia coli (E. coli), Listeria innocua (L. innocua), or Bacillus subtilis (B. subtilis) endospores. ORP, free chlorine (FC), and log reduction were monitored after 5 s (for E. coli and L. innocua) and up to 30 min (for B. subtilis spores) of disinfection. Logistic and exponential models were developed to describe how bacteria reduction varied as a function of ORP at different pH levels. Validation tests were performed in phosphate buffered pH 6.5 and 8.5 cabbage wash water periodically dosed with FC, cabbage extract and a cocktail of Escherichia coli O157:H7 (E. coli O157:H7) and Listeria monocytogenes (L. monocytogenes). The built logistic and exponential models confirmed that at equal ORP values, the inactivation of the surrogate strains was not consistent across pH 6.5 and pH 8.5, with higher reductions at higher pH. This is the opposite of the well-known free chlorine-controlled bacterial inactivation, where the antibacterial effect is higher at lower pH. The validation test results indicated that in the cabbage wash water, the relationship between disinfection efficiency and ORP was consistent with the oxidant demand free systems. The study suggests that ORP cannot serve as a reliable single variable measurement to predict bacterial disinfection in buffered systems. When using ORP to monitor and control the antibacterial effectiveness of the chlorinated wash water, it is crucial to take into account (and control) the pH.

Differential responses to avian pathogenic E. coli and the regulatory role of splenic miRNAs in APEC infection in Silkie chickens.

Avian pathogenic Escherichia coli (APEC) is a bacterial disease that harms the poultry industry worldwide, but its effect on Chinese Silkie has not been reported. Studies on whether there are differences in Silkie individual resistance to APEC and the regulatory role of spleen miRNAs lay the foundation for strategies against APEC. Therefore, 270 Silkie chickens were infected with the median lethal dose of an E. coli O1, O2, and O78 mixture. These chickens were divided into a susceptible group (Group S) and a recovery group (Group R) according to whether they survived 15 days postinfection (dpi). Moreover, 90 uninfected APEC Silkie served as controls (Group C). The splenic miRNA expression profile was examined to evaluate the role of miRNAs in the APEC infection response. Of the 270 Silkies infected with APEC, 144 were alive at 15 dpi. Cluster analysis and principal component analysis (PCA) of splenic miRNAs revealed that the four Group R replicates were clustered with the three Group C replicates and were far from the three Group S replicates. Differentially expressed (DE) miRNAs, especially gga-miR-146b-5p, play essential roles in immune and inflammatory responses to APEC. Functional enrichment analyses of DEmiRNAs suggested that suppression of immune system processes (biological processes) might contribute to susceptibility to APEC and that FoxO signaling pathways might be closely associated with the APEC infection response and postinfection repair. This study paves the way for screening anti-APEC Silkies and provides novel insights into the regulatory role of miRNAs in APEC infection.

Isolation, and Identification of Escherichia coli O157:H7 Recovered from Chicken Meat at Addis Ababa Slaughterhouses.

It is a growing concern that pathogenic bacteria can be found in poultry meat, and an additional problem is the ongoing rise in food-derived bacteria's resistance to antibiotics. A cross-sectional study was conducted from February 2021 to March 2023. This study aimed to isolate, identify and analyze E. coli in poultry meat collected from slaughterhouses in Addis Ababa. A total of 499 samples were collected from fecal content, carcass, hand and knife swab samples by using purposive and systematic random sampling methods. An overall 5.2% Escherichia coli (E. coli O157:H7) prevalence was found in this study. On average, antimicrobial susceptibility tests revealed that the sensitivities of (Escherichia coli) E. coli O157:H7 isolates from carcass swabs, fecal content, manuals, knife swabs and water samples were 62.3%, 52.5%, 53%, 60% and 60%, respectively. However, few (Escherichia coli) E. coli O157:H7 isolates have developed multidrug resistance to some antibiotics, for an overall rate of 13.8%. Knowledge and attitude assessment of the slaughterhouse workers showed that 44.2% had no wash their hands at all and that 125.6% had washed their hands before slaughter commencement. The detection of (Escherichia coli) E. coli O157:H7 isolates from all sample types had a slight prevalence of serious public health concerns. It is important to monitor antibiotic use for both human and animal health in order to make sure that it is safe and effective.

Anticipatory surveillance for detection of Escherichia coli from fresh fruits and vegetables using DuPont BAX System

Escherichia coli is a foodborne pathogen that causes severe illnesses in humans worldwide. Cows are a source of E. coli O157:H7, and raw products contaminated with cattle faeces are typical carriers of the pathogen. The consumption of unhygienic fresh fruits and vegetables provides a potential risk factor for microbial contamination-related infections. In this context, the present work was performed to investigate the prevalence rate of E. coli in fresh fruits and vegetables that were commonly distributed and consumed in Zakho City, Iraq. In addition, the present work also aimed to detect the incidence rate of pathogenic strain E. coli O157:H7, thereafter suggesting the best and most efficient sanitiser for the decontamination of fruits and vegetables. A total of 172 samples, comprising various types of fruits and vegetables, were randomly collected for this cross-sectional study from retail markets in Zakho City. A number of laboratory tests, including DuPont BAX System PCR, microbiological, and biochemical-based techniques were performed for the isolation and identification of E. coli microbial contamination. Out of the 172 samples collected, 32 (18.6%) tested positive for E. coli using traditional enrichment and selective media. The DuPont BAX system technique confirmed that all isolates were E. coli, and none of the isolates were identified as E. coli O157:H7 strain. Furthermore, peracetic acid was found to be a more effective sanitiser than aqueous chlorine for cleaning leafy green vegetables. Despite the absence of the pathogenic strain E. coli O157:H7, the present work highlighted the potential health risk to the community due to E. coli contamination of leafy green vegetables.

The viability of microorganism of probiotic yogurt enriched with bee pollen

ABSTRACT It aims to offer an alternative product to the food industry for the increasing demands of healthy nutrition with production of yogurt containing bee pollen. Probiotic yogurt prepared with different levels of bee pollen (0.5%, 1.5%, 3% and 6%) were evaluated for antimicrobial properties, viability of S. thermophilus, L. bulgaricus, L. acidophilus, and Bifidobacterium spp. during 14 days of refrigerated storage, and resistance to in vitro gastrointestinal conditions. Yogurt samples showed antimicrobial activity against L. monocytogenes, S. Typhimurium, E. coli, E. coli O157:H7, and S. aureus at high level of cell concentration (108 CFU/mL). The viability of S. thermophilus, L. bulgaricus, L. acidophilus, and Bifidobacterium spp. decreased in vitro gastrointestinal digestion model depending on bee pollen content and bacterial species as the application time increased. The simulated gastric and intestinal juice tolerance of bacteria was strain dependent and pH-dependent. The addition bee pollen enhanced the survival of L. acidophilus in both simulated juices.

A novel multifunctional carboxymethyl cellulose packaging film with encapsulated lemon oil for quality enhancement of cherry tomato and baby spinach leaves

This is the first report on fabricating an active edible film based on CMC and lemon essential oil (LEO) micro/nanocapsules for packaging cherry tomatoes and baby spinach leaves. LEO extracted by hydrodistillation from lemon peels was efficiently encapsulated by oil-in-water emulsification method using high dextrose equivalent maltodextrin (MD) as the sole wall material, yielding physically stable MD-LEO micro/nanocapsules with potent cytotoxicity against Caco-2 cells, and antimicrobial activity against foodborne pathogens. Incorporating LEO micro/nanocapsules into CMC confirmed by SEM/FTIR analyses, significantly improved the film's water vapor permeability by 37.50%, increased its thermal stability by 25 ℃, and reduced its moisture content/water absorption. The transparent film demonstrated strong DPPH radicle scavenging activity, UV-blocking ability, low moisture, enhanced tensile strength, and soil biodegradability (96.84%) within 14 days. Direct application of the novel film as a single-layer overwrap to cherry tomatoes and spinach leaves stored at abusive temperature for up to 4 days revealed good prospects of preserving physical appearance, preventing water/texture loss, maintaining pH, and inhibiting growth of aerobic mesophilic/E. coli O157:H7 populations by 0.65 and 1.0 log units, respectively, highlighting that CMC is an optimal vehicle for encapsulated LEO. The data emphasizes the significant contribution of the novel film to active packaging of minimally processed fresh produce and its potential to compete with inert plastic films dominating food markets. Extending the film's applicability range to other pertinent food systems may promote industrial interest for production upscaling as a commercially viable postharvest preservation strategy to meet the demands of sustainable packaging industry in Egypt.

Surveillance of pathogenic bacteria on a food matrix using machine-learning-enabled paper chromogenic arrays

Global food systems can benefit significantly from continuous monitoring of microbial food safety, a task for which tedious operations, destructive sampling, and the inability to monitor multiple pathogens remain challenging. This study reports significant improvements to a paper chromogenic array sensor - machine learning (PCA-ML) methodology sensing concentrations of volatile organic compounds (VOCs) emitted on a species-specific basis by pathogens by streamlining dye selection, sensor fabrication, database construction, and machine learning and validation. This approach enables noncontact, time-dependent, simultaneous monitoring of multiple pathogens (Listeria monocytogenes, Salmonella, and E. coli O157:H7) at levels as low as 1 log CFU/g with over 90% accuracy. The report provides theoretical and practical frameworks demonstrating that chromogenic response, including limits of detection, depends on time integrals of VOC concentrations. The paper also discusses the potential for implementing PCA-ML in the food supply chain for different food matrices and pathogens, with species- and strain-specific identification.