Food Toxins Research Articles

Application of Electrochemical Aptasensors toward Clinical Diagnostics, Food, and Environmental Monitoring: Review.

Aptamers are synthetic bio-receptors of deoxyribonucleic acid (DNA) or ribonucleic acid (RNA) origin selected by the systematic evolution of ligands (SELEX) process that bind a broad range of target analytes with high affinity and specificity. So far, electrochemical biosensors have come up as a simple and sensitive method to utilize aptamers as a bio-recognition element. Numerous aptamer based sensors have been developed for clinical diagnostics, food, and environmental monitoring and several other applications are under development. Aptasensors are capable of extending the limits of current analytical techniques in clinical diagnostics, food, and environmental sample analysis. However, the potential applications of aptamer based electrochemical biosensors are unlimited; current applications are observed in the areas of food toxins, clinical biomarkers, and pesticide detection. This review attempts to enumerate the most representative examples of research progress in aptamer based electrochemical biosensing principles that have been developed in recent years. Additionally, this account will discuss various current developments on aptamer-based sensors toward heavy metal detection, for various cardiac biomarkers, antibiotics detection, and also on how the aptamers can be deployed to couple with antibody-based assays as a hybrid sensing platform. Aptamers can be used in various applications, however, this account will focus on the recent advancements made toward food, environmental, and clinical diagnostic application. This review paper compares various electrochemical aptamer based sensor detection strategies that have been applied so far and used as a state of the art. As illustrated in the literature, aptamers have been utilized extensively for environmental, cancer biomarker, biomedical application, and antibiotic detection and thus have been extensively discussed in this article.

Allergens – food service responsibilities

Allergens – food service responsibilities

A Sustainable Graphene Aerogel Capable of the Adsorptive Elimination of Biogenic Amines and Bacteria from Soy Sauce and Highly Efficient Cell Proliferation.

A graphene aerogel (GA) with a three-dimensional (3D) structure, ultra-lightweight nature, and high hydrophobicity was simply fabricated by the one-step pyrolysis of glucose and ammonium chloride. The as-synthesized GA exhibited a 3D interconnected microporous architecture with a high surface area of ∼2860 m2 g-1 and pore volume of 2.24 cm3 g-1. The hydrophobic GA (10 mg 100 mL-1) demonstrated rapid and excellent adsorption performance for the removal of food toxins such as various biogenic amines (histamine, cadaverine, and spermine) and the hazardous bacterium Staphylococcus aureus (a food contaminant and a cause of poor wound healing) from a liquid matrix with a maximum simultaneous adsorption capacity for multiple biogenic amines of >85.19% (histamine), 74.1% (cadaverine), and 70.11% (spermidine) and a 100% reduction in the viable cell count of S.aureus within 80 min of interaction. The outstanding adsorption capacity can be attributed to a highly interconnected porous network in the 3D architecture and a high surface-to-volume ratio. A case study using soy sauce spiked with multiple biogenic amines showed successful removal of toxins with excellent recyclability without any loss in absorption performance. Biocompatibility of the GA in terms of cell viability was observed even at high concentrations (83.46% and 75.28% at 25 and 50 mg mL-1, respectively). Confirmatory biocompatibility testing was conducted via live/dead cell evaluation, and the morphology of normal lung epithelial cells was examined via scanning electron microscopy showed no cellular shrinkage. Moreover, GA showed excellent removal of live colonies of S.aureus from the food matrix and immunoblotting analysis showed elevated protein expression levels of β-catenin and α-SMA (α-smooth muscle actin). The biocompatible sugar-based GA could simultaneously adsorb multiple biogenic amines and live bacteria and was easy to regenerate via simple separation due to its high floatability, hydrophobicity, surface area, and porosity without any structural and functional loss, making it especially relevant for food safety and biomedical applications.

Calorimetric lateral flow immunoassay detection platform based on the photothermal effect of gold nanocages with high sensitivity, specificity, and accuracy.

BackgroundLateral flow assays (LFA) play an increasingly important role in the rapid detection of various pathogens, pollutants, and toxins.PurposeTo overcome the drawbacks of low sensitivity and poor quantification in LFA, we developed a new calorimetric LFA (CLFA) using gold nanocages (GNCs) due to their high photothermal conversion efficiency, good stability of photophysical properties, and stronger penetrating ability of NIR light.MethodsThiol-polyethylene glycol-succinyl imide ester (HS-PEG-NHS) was modified onto GNCs, and the complex was conjugated with an antibody. Subsequently, the antibody-conjugated GNCs were analyzed by UV/Vis spectrophotometer, transmission electron microscope, high-resolution transmission electron microscope with energy dispersive spectrometer, dynamic light scattering instrument, and Atom force microscope. The GNC-based CLFA of alpha-fetoprotein (AFP) and zearalenone (ZEN), a food toxin, required nitrocellulose strips, a NIR laser source, and an infrared camera.ResultsThe GNC-labeled CLFA platform technique exhibited detection sensitivity, qualitative specificity, and quantitative accuracy. The superior performance of the technique was evident both in sandwich format detection of biomacromolecules (eg, AFP protein) or competitive format detection of small molecules (eg, ZEN). After optimizing various test parameters, GNC-labeled CLFA provided ca. 5-6-fold enhanced sensitivity, higher correlativity (R2>0.99), and more favorable recovery (82–115%) when compared with visual LFA.ConclusionGNC-labeled CLFA may be a promising detection platform with high sensitivity, specificity, and precision.

Synthesis, characterization and applications of silylation based grafted bentonites for the removal of Sudan dyes: Isothermal, kinetic and thermodynamic studies

Abstract The potential of synthesized clay grafted with new organochlorosilanes as an inorganic-organic composite sorbent to remove Sudan dyes have been reported. The synthesized grafted bentonite was characterized via XRD, SEM, EDX, TGA, FT-IR, BET and XRF. The results form FTIR, XRD and DTA/TG confirms the grafting of silyl group to surface/interlayer of clays via reaction with the available –OH groups of clay, moreover, the basel spacing of modified clays were also different from pristine clay. The three kinetics models of adsorption, i.e., Pseudo-first order (Lagergren), Pseudo-Second-order and Fickian (diffusion model) were also studied in detail. The Pseudo-second-order kinetic model fits satisfactorily for adsorption of Sudan dyes. The adsorption behavior of dye on grafted silylated bentonite shows the following order: B-TPCS > B-DPDCS > B-PTCS > B-ODTCS > B-OTCS > B-CTMS. B-TPCS shows maximum efficiency (qe = 95 mg/g) at optimum conditions and follows Langmuir isotherm model which represents the homogeneity of adsorption sites. The results of thermodynamic studies (ΔG°, ΔH° and ΔS°) showed the spontaneous, endothermic and randomness in adsorption process. The method offers high adsorption capacity, cost effective with ease of preparation for Sudan dyes removal, further the modified clays will be explored for the sorption of other food toxins such as mycotoxin in future.

A novel sandwich aptasensor for detecting T-2 toxin based on rGO-TEPA-Au@Pt nanorods with a dual signal amplification strategy

T-2 toxin is a mycotoxin that can cause chronic illnesses, and the detection of T-2 toxin in food is critical for human health. Herein, a novel sandwich aptasensor with a dual signal amplification strategy was developed for the detection of T-2 toxin. Molybdenum disulfide-polyaniline-chitosan-gold nanoparticles (MoS2-PANI-Chi-Au) were processed to the modified glassy carbon electrode (GCE) and used as the aptasensor platform to expedite the electronics transport and immobilize the amino-terminated capture DNA probe by Au–N bonds. The reduced graphene oxide-tetraethylene pentamine-gold@platinum nanorods (rGO-TEPA-Au@Pt NRs) were first synthesized and immobilized with a signal DNA probe. Once T-2 toxin was added into the biosensing system, the aptamer would trap T-2 toxin to turn the signal off. Next, dissociative aptamer hybridized with the capture DNA probe in GCE and linked simultaneously to the signal DNA probe on rGO-TEPA-Au@Pt NRs with another end sequence of aptamer to turn the signal on. Owing to the efficient catalytic ability of bimetallic Au@Pt nanorods, the signal was perfectly amplified through the catalysis of hydrogen peroxide (H2O2) and recorded by chronoamperometry. With the outstanding augment response, the limit of detection reached 1.79 fg mL−1 (3SB/m) and a wide linear range from 10 fg mL−1 to 100 ng mL−1 was presented. The sensitivity of the aptasensor was 19.88 μA⋅μM−1⋅cm−2. Meanwhile, the DNA aptamer-bimetallic nanorod based sensing system presented excellent specificity. The developed aptasensor provides a new platform for T-2 toxin detection with low cost for real sample assays.

Biosensors for early detection of fungi spoilage and toxigenic and mycotoxins in food

Biosensors represent technology that can be applied to several sectors of the food industry from the storage of grains and raw materials, food production/processing, security and protection, packaging of food. Diverse biosensors have emerged in the last decade as an alternative for analyzing microorganisms and toxins in food due to the capability for fast analysis, reproducibility, stability, and accuracy. A wide variety of transducers can be explored for mycotoxin and spoilage, fungi detection, where optical (surface plasmon resonance – SPR and fluorescence), piezoelectric (quartz crystal microbalance – QCM), and electrochemical (impedimetric, potentiometric and amperometric) spectroscopies stand out as main biosensing method. Biological materials (e.g. peptides, enzymes, antibodies, cells, nucleic acids) and bioinspired tools such as aptamers, molecularly imprinted polymers (MIPs) and recombinant antibodies present a high focus as sensing elements on biosensor studies Herein, we present an overview of the recent progress of the development of new biosensors for early detection of fungi (spoilage and toxigenic) and mycotoxins in food.

Внесок ІІ Українського санітарно-харчового з’їзду 1936 р. у розвиток гігієни харчування в Україні

Стаття присвячена висвітленню проблем гігієни харчування на ІІ Українському санітарно-харчовому з’їзді в Одесі у 1936 р. Проблема споживання безпечних харчових продуктів була завжди актуальною для людства. Ця ж проблема потребувала негайного вирішення і в Україні у другій половині 30-х рр. ХХ ст. – в умовах пережитого голодомору і тогочасних змін державної політики країни. Саме через це питання поліпшення харчування почали розглядатися на Першому Всеукраїнському санітарно-харчовому з’їзді (1934 р.) і продовжувалися на ІІ Українському санітарнохарчовому з’їзді у 1936 р. в Одесі. З’ясовано, що в українській історіографії відсутнє наукове дослідження щодо ґрунтовного розгляду діяльності ІІ Українського санітарно-харчового з’їзду, котрий відігравав важливу роль для розвитку гігієни харчування як наукової, так і поліпшення практичної галузі в Україні у 1930-х роках. Метою дослідження є на основі доступних джерел і літератури розглянути питання гігієни харчування на ІІ Українському санітарно-харчовому з’їзді у 1936 р. Ця розвідка є однією зі складових, яка сприятиме кращому розкриттю проблеми розвитку гігієни як науки в Україні у міжвоєнний період 1921-1941 рр. Методологія даного дослідження ґрунтується на сукупності принципів об’єктивності, історизму та системного аналізу фактів і подій. Використано методи теоретичного дослідження, історіографічного, джерелознавчого та термінологічного аналізу. Встановлено, що ІІ Український санітарно-харчовий з’їзд 1936 р. підвів підсумки щодо гігієнічного стану підприємств харчової промисловості країни за останні три роки; визначив завдання подальшої гігієнізації виробництв на харчових підприємствах. Обговорено доповіді з питань санітарної характеристики і гігієнізації виробництв в окремих галузях харчової промисловості й окремих територіальних районах; торгівлі харчовою продукцією в Україні і завдання її санітарно-гігієнічного поліпшення; чергові питання гігієни громадського харчування; санітарно-гігієнічний контроль якості харчових продуктів; профіль і підготовка санітарно-харчових кадрів. Розглянуто науково-дослідні питання: пришвидшені методи хімічного дослідження харчових продуктів, бактеріоскопічні методи дослідження харчових продуктів, діагностика токсину ботулізму у харчових продуктах і корелятивний зв’язок фізико-хімічних і бактеріологічних показників у харчових продуктах. Обговорено зміни до санітарно-харчового законодавства країни: проект санітарно-харчового кодексу, питання нормування солей тяжких металів у харчових продуктах і нормативи санітарно-гігієнічної оцінки харчових продуктів. Опрацьовані питання впровадження дієтичних продуктів у виробництво харчової промисловості.

Molecular Dynamics Study of One-Base Deletion Duplexes Containing the Major DNA Adduct Formed by Ochratoxin A: Effects of Sequence Context and Adduct Ionization State on Lesion Site Structure and Mutagenicity.

Ochratoxin A (OTA) is a ubiquitous food toxin associated with chronic nephropathy in humans and renal carcinogenicity in rodents. The mutational spectra of cells exposed to OTA reveal that one-base deletions comprise the largest percentage (73%) of the total mutations that occur upon OTA exposure. To contribute toward understanding the prevalence of OTA-induced one-base deletion mutations, the present work uses molecular dynamics (MD) simulations to analyze the conformational preferences of one-base deletion duplexes containing OT-G, the major OTA adduct (addition product) at the C8-site of guanine. Specifically, the influence of OT-G in four possible ionization states and three sequence contexts (G1, G2 and G3 in the NarI (5'-G1G2CG3CC-3'), a prokaryotic mutational hotspot sequence) on the structure of the adducted DNA is investigated. Our data reveal that the damaged helices are stable in two (B-type (B) and stacked (S)) conformations that are structurally similar to those adopted by common N-linked C8-guanine lesions. However, the adduct ionization state and sequence context affect the degree of helical distortion and the B/S conformational heterogeneity, which will impact the lesion repair and replication outcomes. This finding correlates with the experimentally reported tissue-specific mutagenicity of OTA exposure. Furthermore, regardless of the adduct conformation, ionization state, or sequence context, more stable lesion-site interactions and lack of disruption of the flanking base pairs in the one-base deletion duplexes compared to the corresponding two-base deletion helices rationalize the greater abundance of OTA induced one-base deletions. Overall, our work provides valuable structural insights that help explain the experimentally observed mutagenicity associated with OTA.

High-affinity phage-displayed peptide as a recognition probe for the detection of Cry2Ad2-3

Cry2A is widely used in transgenic crops in combination with Cry1A toxins. The sensitive and robust detection of Cry2A toxin in food and the environment is necessary to monitor the safety of biopesticides. Here, we describe an approach that involves the use of phage-displayed peptide for the detection of Cry2Ad2-3–the main area of Cry2Ad2 insecticidal activity. After four rounds of panning, six positive monoclonal phage particles were obtained. Pep5 with a sequence of ACSYNHNSKCGGG displayed low cross-reactivity with other Cry toxins. The working range of detection for Cry2Ad2-3 toxin standards in the brush border membrane vesicle (BBMV)–peptide sandwich ELISA was 10–50.625 ng mL−1 and the detection limit (LOD) was 8 ng mL−1. Molecular insight into the interaction of pep5 with Cry2Ad2-3 was gleaned using homology modeling and docking. Molecular docking results showed that high-affinity peptide tended to dock in the groove between the two domains of Cry2Ad2-3. The interactions within the toxin-pep5 complex were due to hydrogen bond and hydrophobic interaction. Pep5 also lead us to trap the binding region. Therefore, peptides may be a cost-efficient alternative for detecting Cry toxins and studying their mechanisms.

INTERNATIONAL AND NATIONAL LEGISLATION TO CONTROL MICTOXINS IN FOOD: REVIEW

Today, the problem of monitoring mycotoxins has become global in connection with climate change, a violation of the ecological balance for the use of intensive technologies for processing crops, through air pollution and the accumulation of products of photochemical reactions (photooxidants), which leads to a decrease in plant resistance to phytopathogens. Every year, the problem of mycotoxicosis is exacerbated, as toxic fungi adapt quickly to new technologies and modern plant protection products. The increase in mycotoxins in foods also relates to the widespread use of nitrogen fertilizers and pesticides. Natural toxins create risks for the health of humans and animals, affect food security and nutrition, reducing people's access to healthy food. The World Health Organization is constantly appealing to national authorities to monitor and ensure that the levels of the most relevant natural toxins in foods are as low as possible and consistent with both national and international requirements. Ukraine's membership in the WTO, an association with the European Union, and the expansion of international trade require solutions to the issues of free movement of goods, safe and healthy food, and, accordingly, an adequate level of protection of life and health of people. One of the most important ways to solve them is to improve and harmonize national food legislation in line with international standards, including on the control of mycotoxins. The purpose of our work was to conduct an analysis of literary sources, international and national legislative acts on the control of mycotoxins in food products throughout the food chain. To prepare the publication, we have used literary sources on the subject of publication, as well as we have conducted a comparative analysis of national and international legislative acts regulating procedures and methods for controlling the residues of mycotoxins in food. An analysis of numerous sources has shown that the issue of monitoring mycotoxins in foods, improving laboratory control and risk-based approach to preventing foodborne mycotoxicosis worries scientists from different countries, including Ukrainian. The analysis of national legislation shows that national standards on maximum levels of pollutants have been revised in Ukraine and a number of standards have been harmonized for methods of monitoring the residues of mycotoxins in feed for productive animals, food products of animal and vegetable origin. Key words: mycotoxins, food chain, food, international law, national legislation, control, safety, risks.

Chocolate Intoxication in a Budgerigar

Chocolate cause clinical symptoms in birds as other animals and is well known food toxin for animals. Toxic components of chocolate are theobromine and caffeine that are within methylxanthines. In this case report; male, four months old budgerigar with abnormal behaviour, hyperactivity, tremors, ataxia, loss of appetite, vomiting, diarrhoea referred to our clinic. According to anamnesis the budgerigar had no health problem up to last 12 hours. After that, the budgerigar ate cake containing chocolate about the size of hazelnut and also 15-20 sugar covered with cacao. After this complaints mentioned above started. In the clinical examination of the budgerigar; body temperature was 41.8oC, respiration rate was 65/minutes. In the Electrocardiography findings, pulsation was 235 beat/minutes, and ventricular arrhythmias was found. In treatment; activated carbon tablet (1-3 mg/kg) were applied to the bird in every 12 hours. Owner informed that the bird got to normal health 24 hours after the treatment. As a result; with this case report choco-late intoxication and treatment were mentioned in budgerigar.

Competitive fluorometric assay for the food toxin T-2 by using DNA-modified silver nanoclusters, aptamer-modified magnetic beads, and exponential isothermal amplification.

The authors describe an aptamer based assay for the mycotoxin T-2. The method is making use of exponential isothermal amplification reaction (EXPAR) and fluorescent silver nanoclusters (AgNCs). Free T-2 and cDNA (which is a DNA that is partially complementary to the aptamer) compete for binding to aptamer-modified magnetic beads. The cDNA collected by magnetic separation can be used as a primer to trigger EXPAR to obtain ssDNA. The C-base-rich ssDNA binds and reduces Ag(I) ion to form fluorescent AgNCs. Fluorescence is measured at excitation/emission wavelengths of 480/525nm. T-2 can be detected by fluorometry with a detection limit as low as 30fg·mL-1. The method was applied to analyse spiked oat and corn, and the average recoveries ranged from 97.3 to 102.3% and from 95.9 to 107.5%, respectively. The results were in good agreement with data of the commercial ELISA kit. The assay is highly sensitive, has a wide analytical range, good specificity and reliable operation. It provides a promising alternative for the standard method for quantitative detection of T-2. Graphical abstract Schematic presentation of fluorometric assay for T-2 based on aptamer-functionalized magnetic beads exponential, isothermal amplification reaction (EXPAR) and fluorescent silver nanoclusters (AgNCs).

Detoxifying potentials of two indigenous adsorbents: imarsil and activated charcoal in the reduction of aflatoxin in vegetable oils consumed in Nigeria

Food contamination with aflatoxin is more prevalent in tropical regions where environmental conditions such as high temperature and humidity prevail, which favour the growth of toxigenic fungiand accumulation of these toxins in food and feeds represent a major threat to human and animal health. In lieu of the previously known adsorbents, adsorption studies of Aflatoxin (AF) were performed using inexpensive, readily available and local adsorbents Imarsil and activated charcoal (AC). Fifteen edible oils were purchases from open markets in Nigeria and screened for aflatoxin using High Performance Liquid Chromatography (HPLC). Thirteen out of the fifteen vegetable oil samples were positive to aflatoxin at the following concentration(172, 123, 195, 142, 46, 107, 96, 116, 22, 33, 228, 17 and 4) ng/kg while two had no detectable AF. Atsix different concentrations (0.5, 1, 1.5, 2, 2.5 and 3%) of Imarsil and activated charcoal (AC) with contact time of 1,2 and 3 h at room temperature (37 °C), the aflatoxin-adsorbing capabilities depend on the adsorbent concentrations and contact time. Imarsil demostrated 100 % adsorption efficiency within one hour. At AF contamination rates of 96–228 ng/kg, activated charcoal was not effective while Imarsil had 100 % removal efficiency within 3 h witha significant reduction (P<0.05) observed at the highest contamination rate and adsorbent concentration. AC demonstrated very mild adsorption activity. Results from this study indicated that Industrial incorporation of Imarsilinto the oil refining process would reduce greatly the menace of aflatoxicosis. Hence, the use of Imarsilshould be encouraged.

Nigella sativaand its Derivatives as Food Toxicity Protectant Agents.

Exposure to food toxins generate multiple adverse health effects. Heavy metals, antibiotics residue, mycotoxins, pesticides and some food additives are examples of the most important food toxins. The common mechanism of toxicity and carcinogenicity effects of food toxins is the generation of oxidative stress that leads to DNA damages. Moreover, based on epidemiologic evidence unhealthy eating habits and food toxicities are associated with cancers occurrence. Therefore, application of bioactive food additives as harmless or safe components in food industry is expensive. Nigella sativa L. is a broadly used herb-drug for various diseases all over the world and has been used as preservative and food additive. Based on various studies N. sativa has shown various pharmacological activities including therapeutic efficacy against different human diseases and antioxidant anti-inflammatory effects against environmental toxins. N. sativa decreases the adverse health effects induced by mentioned food toxins via modulating the action of antioxidant enzymes such as glutathione peroxidase (GPx), glutathione-S-transferase catalase and act as reactive oxygen species (ROS) scavengers in different organs. Besides, N. sativa and thymoquinone (TQ) have protective effects on food products through removal and inhibition of various toxic compounds. Therefore, in the present review we will describe all protective effects of N. sativa and its main constituents, TQ, against food induced toxicities.

Cost-effective sensor detects food toxin

Cost-effective sensor detects food toxin

Toxins in Fermented Foods: Prevalence and Preventions—A Mini Review

Fermented foods (FF) are widely consumed around the world, and FF are one of the prime sources of toxins and pathogenic microbes that are associated with several foodborne outbreaks. Mycotoxins (aflatoxins, fumonisins, sterigmatocystin, nivalenol, deoxynivalenol, zearalenone, ochratoxin, and alternariol), bacterial toxins (shiga toxin and botulinum), biogenic amines, and cyanogenic glycosides are the common toxins found in FF in addition to the pathogenic microbes. Fermented milk products and meat sausages are extremely vulnerable to contamination. Cumulative updated information about a specific topic such as toxins in FF is essential for the improvement of safer preparation and consumption of fermented foods. Accordingly, the current manuscript summarizes the reported mycotoxins, bacterial toxins, and/or toxins from other sources; detection methods and prevention of toxins in FF (use of specific starter culture, optimized fermentation process, and pre- and post-processing treatments); and major clinical outbreaks. This literature survey was made in Scopus, Web of Science, NCBI-PubMed, and Google Scholar using the search terms “Toxins” and “Fermented Foods” as keywords. The appropriate scientific documents were screened for relevant information and they were selected without any chronological restrictions.

Enumeration of the microbiota and microbial metabolites in processed cassava products from Madagascar and Tanzania

Cassava processing practices vary among communities and countries with implications for food safety. The study examined the microbiota and microbial metabolite profiles of 126 samples of sun-dried cassava products: grits, improved chips, improved flour, kivunde, and makopa from Tanzania, and mangahazo maina from Madagascar. All samples were free of Salmonella spp. Only 12.5% makopa, 6.7% of mechanically processed flour, and 25% of chips conformed to yeast/mold regulatory limits (103 cfu/g). Among the most agriculturally important mycotoxins, aflatoxins (B1, B2, G1, and M1) were detected in 6.3–11.9%, fumonisins (B1, B2 and B3) in 3.2–41.3%, and zearalenone in 41.3% of the samples. A few samples of improved chips, improved flour, and makopa contained high aflatoxin B1 content. Some emerging mycotoxins: emodin, beauvericin, moniliformin, sterigmatocystin, alternariol methyl ether, nivalenol, mycophenolic acid, enniatin B, and enniatin B1 were detected. The most prevalent microbial metabolites were emodin (75.4%), tryptophol (67.5%), equisetin (61.9%), and beauvericin (51.6%), at mean concentrations of 8.8 μg/kg, 794.1 μg/kg, 277.2 μg/kg, and 29.5 μg/kg, respectively. Emodin and Beauvericin are the only emerging mycotoxins in this group and the mean concentrations are the lowest. Nevertheless, regular surveillance along the cassava food chain is recommended for early detection of emerging mycotoxins to prevent health problems associated with ingestion of unexpected toxins in foods.

Efficacy of a novel bacteriocin isolated from Lysinibacillus sp. against Bacillus pumilus

A strain of Lysinibacillus, isolated from spoiled fruits and vegetable wastes, was found having an inhibitory effect against foodborne pathogens. Subjected to study of different physico-chemical parameters followed by characterization based on the 16S rRNA gene, it was found exhibiting resemblance to L. boronitolerans (99%), L. xylanilyticus (98%) and L. macroides (97%) respectively. The isolate was annotated as Lysinibacillus JX402121 and found that the production capacity of the specific product recognized as bacteriocin during growth in medium the bacteriocin was further purified to homogeneity by ammonium sulphate precipitation followed by gel filtration chromatography. MALDI-TOF/MS analysis of the substance revealed it to be a 51 kDa bacteriocin, showing greater resemblance with a catalytic bacterial protein, uracil-5-methyl transferase. Based on the physico-chemical characteristics and N-terminal (IKKAPVQKNENYEV) sequence, this novel bacteriocin was found representing a class III bacteriocin. This was found highly active against foodborne bacterial pathogens, Bacillus pumilus (MIC-22 μg/mL), which is responsible for pumilacidins like food toxin. Having great potential against foodborne pathogens, Lysinibacillus JX402121 isolate will be utilized in the production of bacteriocin that acts as a bio-preservative agent against different food-borne pathogens.

Impedance Sensing Platform for Detection of the Food Pathogen Listeria monocytogenes

A great improvement in food safety and quality controls worldwide has been achieved through the development of biosensing platforms. Foodborne pathogens continue to cause serious outbreaks, due to the ingestion of contaminated food. The development of new, sensitive, portable, high-throughput, and automated platforms is a primary objective to allow detection of pathogens and their toxins in foods. Listeria monocytogenes is one common foodborne pathogen. Major outbreaks of listeriosis have been caused by a variety of foods, including milk, soft cheeses, meat, fermented sausages, poultry, seafood and vegetable products. Due to its high sensitivity and easy setup, electrochemical impedance spectroscopy (EIS) has been extensively applied for biosensor fabrication and in particular in the field of microbiology as a mean to detect and quantify foodborne bacteria. Here we describe a miniaturized, portable EIS platform consisting of a microfluidic device with EIS sensors for the detection of L. monocytogenes in milk samples, connected to a portable impedance analyzer for on-field application in clinical and food diagnostics, but also for biosecurity purposes. To achieve this goal microelectrodes were functionalized with antibodies specific for L. monocytogenes. The binding and detection of L. monocytogenes was achieved in the range 2.2 × 103 cfu/mL to 1 × 102 with a Limit of Detection (LoD) of 5.5 cfu/mL.