Susceptibility of the Different Oxygen-Sensing Probes to Interferences in Respirometric Bacterial Assays with Complex Media.

Respirometric microbial assays are gaining popularity, but their uptake is limited by the availability of optimal O sensing materials and the challenge of validating assays with complex real samples. We conducted a comparative evaluation of four different O-sensing probes based on Pt-porphyrin phosphors in respirometric bacterial assays performed on standard time-resolved fluorescence reader. The macromolecular MitoXpress, nanoparticle NanO2 and small molecule PtGlc and PtPEG probes were assessed with cells in five growth media: nutrient broth (NB), McConkey (MC), Rapid Coliform ChromoSelect (RCC), M-Lauryl lauryl sulfate (MLS), and Minerals-Modified Glutamate (MMG) media.

Combining the oxygen sensor based respirometry and 16S rRNA amplicon sequencing for the analysis of microbiota in commercial mince products.

In this study, rapid respirometric microbial testing was combined with 16S rRNA amplicon sequencing, to assess the composition of microbiota in a total of 64 samples of commercial beef, turkey, lamb and pork mince. The O sensor-based respirometry system, while producing the anticipated total aerobic viable counts (TVC) data and patterns for most samples, also revealed unusual (linear) respiration profiles for some samples, mostly lamb and pork mince. The TVC values for beef mince, produced by respirometry and calculated using the available calibration equation, correlated well with the conventional plate counting method, ISO 4833-1:2013, 2013, while for the other species the correlation was less good.

Simultaneous Removal of Mycotoxins by a New Feed Additive Containing a Tri-Octahedral Smectite Mixed with Lignocellulose.

Simultaneous removal of mycotoxins has been poorly addressed, and a limited number of studies have reported the efficacy of feed additives in sequestering a large spectrum of mycotoxins. In this study, a new mycotoxin-adsorbing agent was obtained by properly mixing a tri-octahedral smectite with a lignocellulose-based material. At a dosage of 1 mg mL, these materials simultaneously adsorbed frequently occurring mycotoxins and did not exert a cytotoxic effect on intestinal cells.

Mineral Composition and Bioaccessibility in Rocket and Purslane after Zn Biofortification Process.

Zinc (Zn) is an essential key nutrient in different biochemical and physiological processes. The nutritional deficit of this mineral element is estimated to affect the health of over 3 billion people worldwide. Several strategies are available to reduce the negative impact of mineral malnutrition; among them, biofortification is the practice of deliberately increasing the nutrients and healthy compounds in the edible parts of vegetables.

A sensor-based system for rapid on-site testing of microbial contamination in meat samples and carcasses.

Aims: To develop an oxygen sensor-based method for testing total aerobic viable counts (TVC) in raw meat samples and cattle carcass swabs, which is rapid, simple, affordable, provides good sensitivity and analytical performance and allows on-site use.

Methods And Results: The test uses the same sample preparation procedure as the established plate counting TVC method for meat samples and carcasses, ISO4833-1:2013. After this liquid samples are transferred into standard 25-ml vials with built-in phosphorescent O  sensors and incubated on a block heater with hourly readings of sensor signals with a handheld reader, to determine signal threshold time (TT, hours) for each sample.

A Simple Sensor System for Onsite Monitoring of O in Vacuum-Packed Meats during the Shelf Life.

Vacuum packaging (VP) is used to reduce exposure of retail meat samples to ambient oxygen (O) and preserve their quality. A simple sensor system produced from commercial components is described, which allows for non-destructive monitoring of the O concentration in VP raw meat samples. Disposable O sensor inserts were produced by spotting small aliquots of the cocktail of the Pt-benzoporphyrin dye and polystyrene in ethyl acetate onto pieces of a PVDF membrane and allowing them to air-dry.

Facile biosensor-based system for on-site quantification of total viable counts in food and environmental swabs.

We describe a new biosensor platform for rapid and simple quantification of total aerobic viable counts of bacteria (TVC) in food and environmental swabs by oxygen respirometry. The system uses disposable swab vials with phosphorescent oxygen sensors integrated in the bottom part, a small block heater/incubator and a handheld sensor reader. In the testing, groups of 1-20 swabs samples were prepared using the standard method (ISO, 18593:2018) in sensor vials, which were then incubated at 30 °C and measured hourly in a contactless, non-invasive manner.

Development of a DNA-based biosensor for the fast and sensitive detection of ochratoxin A in urine.

In this paper, a novel DNA-based biosensor is proposed, which is based on paramagnetic microbeads carrying an ochratoxin A (OTA) capture aptamer. A sandwich-like detection complex is linked to the capture aptamer and is able to trigger, in presence of OTA, an isothermal rolling circle amplification (RCA) reaction. This latter generated autocatalytic units with a peroxidase activity (DNAzyme) that, in presence of a proper substrate, gave a blue-coloured product visible by the naked eye.

Equilibrium Isotherm Approach to Measure the Capability of Yeast Cell Wall to Adsorb .

Yeast cell wall (YCW) products are currently used as substitutes to antibiotic growth promoters, to improve animal performances, and to reduce the incidence of infectious diseases in livestock. They are claimed to bind enteropathogens, thus interfering with their colonization in the intestinal mucosa. Although the anti-infectious activity of YCW products on Gram-positive pathogens like has been reported , evidences on the adsorption of by YCW fractions are not yet available.

Antimicrobial Activity of Yeast Cell Wall Products Against .

Yeast cell wall (YCW) products are used worldwide as alternatives to antibiotics growth promoters for health and performances improvement in livestock. The success of yeast and YCW products as feed additives in farm animals' nutrition relies on their capacity to bind enteropathogenic bacteria and on their immunomodulatory activity. studies report their anti-infectious activity on Gram-positive pathogens like clostridia.

Antimicrobial properties of rosin acids-loaded nanoparticles against antibiotic-sensitive and antibiotic-resistant foodborne pathogens.

Rosin acids (RA) from coniferous trees are used in folk medicine for healing various skin infections. Despite the antimicrobial potential of RA, their poor solubility in aqueous media may limit their use. In this work RA-loaded polyethylene glycol-poly(lactic-co-glycolic acid) nanoparticles (RA-NPs) with enhanced antimicrobial properties against foodborne bacterial pathogens were produced.

Comparative efficacy of agricultural by-products in sequestering mycotoxins.

Background: Biosorption using agricultural by-products has been proven as a low-cost and safe way to sequester mycotoxins. Few agricultural by-products have been studied for their efficacy in adsorbing simultaneously a large range of mycotoxins. The present work compared the ability of 51 agricultural by-products to adsorb mycotoxins from liquid mediums simulating physiological pH values, and it studied the mechanism for mycotoxin adsorption by isotherm adsorption experiments.

Eubiotics for Food Security at Farm Level: Yeast Cell Wall Products and Their Antimicrobial Potential Against Pathogenic Bacteria.

The population increase in the last century was the first cause of the industrialization of animal productions, together with the necessity to satisfy the high food demand and the lack of space and land for the husbandry practices. As a consequence, the farmers moved from extensive to intensive agricultural systems and introduced new practices, such as the administration of antimicrobial drugs. Antibiotics were then used as growth promoters and for disease prevention.

Infection cycle of Artichoke Italian latent virus in tobacco plants: meristem invasion and recovery from disease symptoms.

Nepoviral infections induce recovery in fully expanded leaves but persist in shoot apical meristem (SAM) by a largely unknown mechanism. The dynamics of infection of a grapevine isolate of Artichoke Italian latent virus (AILV-V, genus Nepovirus) in tobacco plants, including colonization of SAM, symptom induction and subsequent recovery of mature leaves from symptoms, were characterized. AILV-V moved from the inoculated leaves systemically and invaded SAM in 7 days post-inoculation (dpi), remaining detectable in SAM at least up to 40 dpi.

Evaluation of reference genes for quantitative reverse-transcription polymerase chain reaction normalization in infected tomato plants.

The quantification of messenger RNA expression levels by real-time reverse-transcription polymerase chain reaction requires the availability of reference genes that are stably expressed regardless of the experimental conditions under study. We examined the expression variations of a set of eight candidate reference genes in tomato leaf and root tissues subjected to the infection of five taxonomically and molecularly different plant viruses and a viroid, inducing diverse pathogenic effects on inoculated plants. Parallel analyses by three commonly used dedicated algorithms, geNorm, NormFinder and BestKeeper, showed that different viral infections and tissues of origin influenced, to some extent, the expression levels of these genes.