Analytical methods for determination of mycotoxins: a review

Molecularly imprinted polymer coupled to UHPLC-MS/MS for the analysis of phomopsins in lupin samples

The demand for plant-based protein sources in the food industry has significantly increased in recent years, leading to the introduction of legume-based products as meat substitutes. However, concerns regarding food quality have emerged, particularly related to the presence of mycotoxins. This study addresses the need for the sensitive detection of phomopsins (PHOs), a class of peptide-based toxins. A selective extraction method using molecularly imprinted polymer (MIP) coupled with ultra-high performance liquid chromatography and tandem mass spectrometry (UHPLC-MS/MS) was focused on the most toxic Phomopsin A (PHO-A). A rapid ultrasonochemical synthesis of MIP (5 min) was proposed and its performance was optimized in response to various factors, including the choice of dummy template and the selection of the monomer. The methacrylic acid-vinyl pyridine (MAA-VP) MIP exhibited high selectivity and affinity for PHO-A. The method was tested in lupin samples and the validation, according to SANTE/11312/2021 international guidelines, gave excellent recovery (80-90 %), low matrix effects, and high accuracy and precision. Real samples analysis confirmed the presence of PHO-A in artificially fungal inoculated lupins, with levels ranging from 0.377 to 0.576 mg kg-1. In order to identify further PHOs, a semi-untargeted approach using multiple reaction monitoring-information dependent acquisition-enhanced product ion (MRM-IDA-EPI) was developed. PHO-B, PHO-D, PHO-E and PHO-P, rarely previously reported in lupin matrix, were tentatively identified. This study accounts for the effectiveness of MIP-based extraction coupled with UHPLC-triple quadrupole with linear ionic trap-MS/MS (UHPLC-QqQ-LIT-MS/MS) for quantification of PHO-A and putative detection of other PHOs, offering a promising method for investigating this class of toxins in food.

Infant exposure to ochratoxin A, zearalenone, and deoxynivalenol from the consumption of milk formula and baby cereal in Chile

Ochratoxin A (OTA), zearalenone (ZEN), and deoxynivalenol (DON) are mycotoxins whose exposure is associated with various adverse health effects, including cancer and renal disorders, estrogenic effects, and immunosuppressive and gastrointestinal disorders, respectively. Infants (<2 years) are the most vulnerable group to mycotoxins, representing a unique combination of restricted food consumption types, low body weight, lower ability to eliminate toxins, and more future years to accumulate toxins. This study aimed to estimate the infant́s exposure to OTA, DON, and ZEN due to the consumption of milk formula and baby cereals in Chile. Milk formula samples (n = 41) and baby cereals (n = 30) were collected and analyzed using commercial ELISA kits for OTA, DON, and ZEA determination. Exposure was assessed by the Estimated Daily Intake (EDI) approach (mean and worst-case scenario, WCS) with the levels found in a modified Lower Bound (mLB) and Upper Bound (UB); ideal consumption (<6m, 7-12 m, and 13-24 m); adjusted by the weight of each group. The risk was estimated by comparing the EDI with a reference tolerable daily intake or by the margin of exposure (MOE) in the case of OTA. DON and OTA occurrence in infant formula were 34 % and 41 %, respectively. The co-occurrence between these mycotoxins was 22 %. Mycotoxin contents were below LOQ values except for OTA determined in one sample (0.29 ng/ml). No milk formulae were contaminated with ZEN. In the case of baby cereals, the occurrences were 17 % for OTA, 30 % for DON, and 7 % for ZEN, all below LOQ. Co-occurrence was seen in two samples between ZEN and OTA. According to exposure calculations, the MOE for OTA was less than 10,000 in all models for milk formula between 0 to 12 months of age and in the UB and WCS for cereal consumption. Health concerns were observed for DON in the WCS and UB for milk consumption in all ages and only in the UB WCS for cereal consumption. Considering the high consumption of milk formula in these age groups, regulation of OTA and other co-occurring mycotoxins in infant milk and food is strongly suggested.

Recent advances in nanomaterial-based optical biosensors for food safety applications: Ochratoxin-A detection, as case study

Global population growth tremendously impacts the global food industry, endangering food safety and quality. Mycotoxins, particularly Ochratoxin-A (OTA), emerge as a food chain production threat, since it is produced by fungus that contaminates different food species and products. Beyond this, OTA exhibits a possible human toxicological risk that can lead to carcinogenic and neurological diseases. A selective, sensitive, and reliable OTA biodetection approach is essential to ensure food safety. Current detection approaches rely on accurate and time-consuming laboratory techniques performed at the end of the food production process, or lateral-flow technologies that are rapid and on-site, but do not provide quantitative and precise OTA concentration measurements. Nanoengineered optical biosensors arise as an avant-garde solution, providing high sensing performance, and a fast and accurate OTA biodetection screening, which is attractive for the industrial market. This review core presents and discusses the recent advancements in optical OTA biosensing, considering engineered nanomaterials, optical transduction principle and biorecognition methodologies. Finally, the major challenges and future trends are discussed, and current patented OTA optical biosensors are emphasized for a particular promising detection method.

Application of Biosensors for the Detection of Mycotoxins for the Improvement of Food Safety

Mycotoxins, secondary metabolites synthesized by various filamentous fungi genera such as Aspergillus, Penicillium, Fusarium, Claviceps, and Alternaria, are potent toxic compounds. Their production is contingent upon specific environmental conditions during fungal growth. Arising as byproducts of fungal metabolic processes, mycotoxins exhibit significant toxicity, posing risks of acute or chronic health complications. Recognized as highly hazardous food contaminants, mycotoxins present a pervasive threat throughout the agricultural and food processing continuum, from plant cultivation to post-harvest stages. The imperative to adhere to principles of good agricultural and industrial practice is underscored to mitigate the risk of mycotoxin contamination in food production. In the domain of food safety, the rapid and efficient detection of mycotoxins holds paramount significance. This paper delineates conventional and commercial methodologies for mycotoxin detection in ensuring food safety, encompassing techniques like liquid chromatography, immunoassays, and test strips, with a significant emphasis on the role of electrochemiluminescence (ECL) biosensors, which are known for their high sensitivity and specificity. These are categorized into antibody-, and aptamer-based, as well as molecular imprinting methods. This paper examines the latest advancements in biosensors for mycotoxin testing, with a particular focus on their amplification strategies and operating mechanisms.

Prediction of Deoxynivalenol Contamination in Wheat via Infrared Attenuated Total Reflection Spectroscopy and Multivariate Data Analysis

The climate crisis further exacerbates the challenges for food production. For instance, the increasingly unpredictable growth of fungal species in the field can lead to an unprecedented high prevalence of several mycotoxins, including the most important toxic secondary metabolite produced by Fusarium spp., i.e., deoxynivalenol (DON). The presence of DON in crops may cause health problems in the population and livestock. Hence, there is a demand for advanced strategies facilitating the detection of DON contamination in cereal-based products. To address this need, we introduce infrared attenuated total reflection (IR-ATR) spectroscopy combined with advanced data modeling routines and optimized sample preparation protocols. In this study, we address the limited exploration of wheat commodities to date via IR-ATR spectroscopy. The focus of this study was optimizing the extraction protocol for wheat by testing various solvents aligned with a greener and more sustainable analytical approach. The employed chemometric method, i.e., sparse partial least-squares discriminant analysis, not only facilitated establishing robust classification models capable of discriminating between high vs low DON-contaminated samples adhering to the EU regulatory limit of 1250 μg/kg but also provided valuable insights into the relevant parameters shaping these models.

A zinc-air battery assisted self-powered electrochemical sensor for sensitive detection of microcystin-RR

Building a high-performance sensing platform is the key to developing sensitive sensors. Herein, a highly sensitive self-powered electrochemical sensor (SPES) was constructed using a WO3·H2O film as the cathode prepared by a hydrothermal method and Zn as the anode, and it could be applied to sensitive detection of microcystin (MC-RR). The WO3·H2O film with a larger specific surface area could boost the oxygen reduction reaction (ORR), which could achieve signal amplification and significantly increase the sensitivity of the sensors. Under the optimal conditions, there was a good linear relationship between the increased electrical power density and the logarithm of MC-RR concentration with a detection limit of 1.31 × 10-15 M (S/N = 3). This method had good anti-interference ability and stability when applied to the determination of MC-RR content in actual samples, which could boost the potential application of electrochemical sensors in the field of environmental monitoring.

Comprehensive Insights into Ochratoxin A: Occurrence, Analysis, and Control Strategies

Ochratoxin A (OTA) is a toxic mycotoxin produced by some mold species from genera Penicillium and Aspergillus. OTA has been detected in cereals, cereal-derived products, dried fruits, wine, grape juice, beer, tea, coffee, cocoa, nuts, spices, licorice, processed meat, cheese, and other foods. OTA can induce a wide range of health effects attributable to its toxicological properties, including teratogenicity, immunotoxicity, carcinogenicity, genotoxicity, neurotoxicity, and hepatotoxicity. OTA is not only toxic to humans but also harmful to livestock like cows, goats, and poultry. This is why the European Union and various countries regulate the maximum permitted levels of OTA in foods. This review intends to summarize all the main aspects concerning OTA, starting from the chemical structure and fungi that produce it, its presence in food, its toxicity, and methods of analysis, as well as control strategies, including both fungal development and methods of inactivation of the molecule. Finally, the review provides some ideas for future approaches aimed at reducing the OTA levels in foods.

Smartphone-Controlled Aptasensor for Voltammetric Detection of Patulin in Apple Juice

Patulin (PAT) is a mycotoxin that adversely affects the health of humans and animals. PAT can be particularly found in products such as apples and apple juice and can cause many health problems if consumed. Therefore, accurate and sensitive determination of PAT is very important for food quality and human and animal health. A voltammetric aptasensor was introduced in this study for PAT determination while measuring the changes at redox probe signal. The limit of detection (LOD) was found to be 0.18 pg/mL in the range of 1-104 pg/mL of PAT in buffer medium under optimum experimental conditions. The selectivity of the PAT aptasensor against ochratoxin A, fumonisin B1 and deoxynivalenol mycotoxins was examined and it was found that the aptasensor was very selective to PAT. PAT determination was performed in an apple juice medium for the first time by using a smartphone-integrated portable device, and accordingly, an LOD of 0.47 pg/mL was achieved in diluted apple juice medium. A recovery range of 91.24-93.47% was obtained for PAT detection.

Co-Occurrence of Aflatoxin B1, Zearalenone and Ochratoxin A in Feed and Feed Materials in Central Italy from 2018 to 2022

Mycotoxin contamination of feed and feed materials represent a serious health hazard. This study details the occurrence of aflatoxin B1 (AFB1), zearalenone (ZEN) and ochratoxin A (OTA) in 826 feed and 617 feed material samples, collected in two Italian Regions (Umbria and Marche) from 2018 to 2022 analyzed using a UPLC-FLD platform. The developed method was validated and accredited (ISO/IEC 17025) with satisfactory accuracy and precision data obtained in repeatability and intralaboratory reproducibility conditions. Feed had a higher incidence of contaminated samples (26%) with respect to feed materials (6%). AFB1 was found up to 0.1045 mg/kg in cattle feeds and 0.1234 mg/kg in maize; ZEN was detected up to 6.420 mg/kg in sheep feed while OTA was rarely reported and in lower concentrations (up to 0.085 mg/kg). Co-contamination of at least two mycotoxins was reported in 0.8% of the analyzed samples. The incidence of above maximum content/guidance level samples was 2% for feed and feed materials while almost 3-fold-higher for maize (5.8%) suggesting how mycotoxin contamination can affect some matrices more than others. Obtained data can be useful to improve official monitoring plans and therefore further raise awareness of this issue between agriculture stakeholders, healthcare entities and non-professionals.

Mycotoxins-Imprinted Polymers: A State-of-the-Art Review

Mycotoxins are toxic metabolites of molds which can contaminate food and beverages. Because of their acute and chronic toxicity, they can have harmful effects when ingested or inhaled, posing severe risks to human health. Contemporary analytical methods have the sensitivity required for contamination detection and quantification, but the direct application of these methods on real samples is not straightforward because of matrix complexity, and clean-up and preconcentration steps are needed, more and more requiring the application of highly selective solid-phase extraction materials. Molecularly imprinted polymers (MIPs) are artificial receptors mimicking the natural antibodies that are increasingly being used as a solid phase in extraction methods where selectivity towards target analytes is mandatory. In this review, the state-of-the-art about molecularly imprinted polymers as solid-phase extraction materials in mycotoxin contamination analysis will be discussed, with particular attention paid to the use of mimic molecules in the synthesis of mycotoxin-imprinted materials, to the application of these materials to food real samples, and to the development of advanced extraction methods involving molecular imprinting technology.

Innovative approaches for mycotoxin detection in various food categories

Mycotoxins (MTs), produced by filamentous fungi, represent a severe hazard to the health of humans and food safety, affecting the quality of various agricultural products. They can contaminate a wide range of foods, during any processing phase before or after harvest. Animals and humans who consume MTs-contaminated food or feed may experience acute or chronic poisoning, which may result in serious pathological consequences. Accordingly, developing rapid, easy, and accurate methods of MTs detection in food becomes highly urgent and critical as a quality control and to guarantee food safety and lower health hazards. In this review, we highlighted and discussed innovative approaches like biosensors, fluorescent polarization, capillary electrophoresis, infrared spectroscopy, and electronic noses for MT identification pointing out current challenges and future directions. The limitations, current challenges, and future directions of conventional detection methods versus innovative methods have also been highlighted and discussed.

Production of AFB1 High-Specificity Monoclonal Antibody by Three-Stage Screening Combined with the De-Homologation of Antibodies and the Development of High-Throughput icELISA

To achieve accurate detection of AFB1 toxin content in agricultural products and avoid false-positive rates in the assays, the specificity of mAbs is critical. We improved the specificity of the prepared monoclonal antibodies by modifying the traditional limiting dilution subcloning method. The traditional finite dilution method was modified with three-stage screening (the trending concentration of standards used in the screening is low-high-low) to achieve high specificity in pre-cell screening and increased the number of subclones to 10 to achieve the de-homologation of antibodies. A modified limiting dilution obtained a highly specific AFB1 monoclonal cell line, ZFG8, with a 50% inhibition concentration (IC50) of 0.3162 ng/mL. Notably, it exhibited the highest specificity compared to anti-AFB1 monoclonal antibodies prepared by other investigators. The maximum cross-reactivity of the mAb with structural analogues for AFB2, AFG1, AFG2, and AFM1 was 0.34%. The results showed that this type of screening improves the monoclonal antibodies' specificity. Based on this ZFG8 monoclonal antibody, an icELISA assay was established with an IC50 of 0.2135 ng/mL for AFB1. The limit of the linear detection range of icELISA is 0.0422-1.29267 ng/mL with reasonable specificity and precision. The recoveries of AFB1 in samples of corn flour and wheat meal ranged from 84 to 107%, with CVs below 9.3%. The recoveries of structural analogues (AFB2, AFM1, AFG1, and AFG2) were less than 10% in both corn flour and wheat meal. The results showed that the prepared AFB1 monoclonal antibody could accurately and specifically recognize AFB1 residues in agricultural products while ignoring the effects of other structural analogues.

Mycotoxins in Vegetable Oils: A Review of Recent Developments, Current Challenges and Future Perspectives in Sample Preparation, Chromatographic Determination, and Analysis of Real Samples

Mycotoxins are toxic compounds that are formed as secondary metabolites by some fungal species that contaminate crops during pre- and postharvest stages. Exposure to mycotoxins can lead to adverse health effects in humans, such as carcinogenicity, mutagenicity, and teratogenicity. Hence, there is a need to develop analytical methods for their determination in vegetable oils that possess high sensitivity and selectivity. In the current review (116 references), the recent developments, current challenges, and perspectives in sample preparation techniques and chromatographic determination are summarized. It is impressive that current sample preparation techniques such as dispersive liquid-liquid microextraction (DLLME), quick, easy, cheap, rugged, and safe method (QuEChERS) and solid phase extraction (SPE) have exhibited high extraction recoveries and minimal matrix effects. However, a few studies have reported signal suppression or enhancement. Regarding chromatographic techniques, high sensitivity and selectivity have been reported by liquid chromatography coupled to fluorescence detection, tandem mass spectrometry, or high-resolution mass spectrometry. Furthermore, current challenges and perspectives in this field are tentatively proposed.

Recent Advances in the Detection of Food Toxins Using Mass Spectrometry

Edibles are the only source of nutrients and energy for humans. However, ingredients of edibles have undergone many physicochemical changes during preparation and storage. Aging, hydrolysis, oxidation, and rancidity are some of the major changes that not only change the native flavor, texture, and taste of food but also destroy the nutritive value and jeopardize public health. The major reasons for the production of harmful metabolites, chemicals, and toxins are poor processing, inappropriate storage, and microbial spoilage, which are lethal to consumers. In addition, the emergence of new pollutants has intensified the need for advanced and rapid food analysis techniques to detect such toxins. The issue with the detection of toxins in food samples is the nonvolatile nature and absence of detectable chromophores; hence, normal conventional techniques need additional derivatization. Mass spectrometry (MS) offers high sensitivity, selectivity, and capability to handle complex mixtures, making it an ideal analytical technique for the identification and quantification of food toxins. Recent technological advancements, such as high-resolution MS and tandem mass spectrometry (MS/MS), have significantly improved sensitivity, enabling the detection of food toxins at ultralow levels. Moreover, the emergence of ambient ionization techniques has facilitated rapid in situ analysis of samples with lower time and resources. Despite numerous advantages, the widespread adoption of MS in routine food safety monitoring faces certain challenges such as instrument cost, complexity, data analysis, and standardization of methods. Nevertheless, the continuous advancements in MS-technology and its integration with complementary techniques hold promising prospects for revolutionizing food safety monitoring. This review discusses the application of MS in detecting various food toxins including mycotoxins, marine biotoxins, and plant-derived toxins. It also explores the implementation of untargeted approaches, such as metabolomics and proteomics, for the discovery of novel and emerging food toxins, enhancing our understanding of potential hazards in the food supply chain.

Low-Cost Pocket Fluorometer and Chemometric Tools for Green and Rapid Screening of Deoxynivalenol in Durum Wheat Bran

Cereal crops are frequently contaminated by deoxynivalenol (DON), a harmful type of mycotoxin produced by several Fusarium species fungi. The early detection of mycotoxin contamination is crucial for ensuring safety and quality of food and feed products, for preventing health risks and for avoiding economic losses because of product rejection or costly mycotoxin removal. A LED-based pocket-size fluorometer is presented that allows a rapid and low-cost screening of DON-contaminated durum wheat bran samples, without using chemicals or product handling. Forty-two samples with DON contamination in the 40-1650 µg/kg range were considered. A chemometric processing of spectroscopic data allowed distinguishing of samples based on their DON content using a cut-off level set at 400 µg/kg DON. Although much lower than the EU limit of 750 µg/kg for wheat bran, this cut-off limit was considered useful whether accepting the sample as safe or implying further inspection by means of more accurate but also more expensive standard analytical techniques. Chemometric data processing using Principal Component Analysis and Quadratic Discriminant Analysis demonstrated a classification rate of 79% in cross-validation. To the best of our knowledge, this is the first time that a pocket-size fluorometer was used for DON screening of wheat bran.

Dispersive solid phase extraction using a hydrophilic molecularly imprinted polymer for the selective extraction of patulin in apple juice samples

A molecularly imprinted polymer with a specific selectivity for patulin was successfully synthesized. The molecularly imprinted material was prepared using the two functional monomers dopamine and melamine and formaldehyde as the cross-linker. The resulting material possessed a large number of hydrophilic groups, such as hydroxyls, imino groups, and ether linkages. For the first time, uric acid was used as a dummy template for its structural similarity to patulin. Comprehensive characterization and detailed studies of the adsorption process were carried out via adsorption isotherms, while the rate-limiting steps were investigated using adsorption kinetics. Separation, determination, and quantification of patulin were achieved by ultra-high performance liquid chromatography coupled with both photodiode array detection and tandem mass spectrometry. The latter was applied to patulin confirmation in the analysis of real samples. The methodology was validated in 20 apple juice samples. The results showed that the developed hydrophilic molecularly imprinted polymer had high selectivity and specific adsorption towards patulin, with mean recoveries ranging between 85 and 90% and a relative standard deviation lower than 15%. The developed molecularly imprinted polymer exhibited good linearity in the range 1-100 ng mL-1 with coefficient of determination (R2) > 0.99. The limit of detection was 0.5 ng mL-1, and the limit of quantification was 1 ng g-1. The developed method showed a good purification capacity for apple juices due to its hydrophilic nature and the polar interactions established with the target analyte.

Current Trends in Mycotoxin Detection with Various Types of Biosensors

One of the most important tasks in food safety is to properly manage the investigation of mycotoxin contamination in agricultural products and foods made from them, as well as to prevent its occurrence. Monitoring requires a wide range of analytical methods, from expensive analytical procedures with high-tech instrumentation to significantly cheaper biosensor developments or even single-use assays suitable for on-site monitoring. This review provides a summary of the development directions over approximately a decade and a half, grouped according to the biologically sensitive components used. We provide an overview of the use of antibodies, molecularly imprinted polymers, and aptamers, as well as the diversity of biosensors and their applications within the food industry. We also mention the possibility of determining multiple toxins side by side, which would significantly reduce the time required for the analyses.

Multi-Mycotoxin Analysis in Italian Grains Using Ultra-High-Performance Chromatography Coupled to Quadrupole Orbitrap Mass Spectrometry

Mycotoxins are a major source of contamination in cereals, posing risks to human health and causing significant economic losses to the industry. A comprehensive strategy for the analysis of 21 mycotoxins in Italian cereal grain samples (n = 200) was developed using a simple and quick sample preparation method combined with ultra-high-performance liquid chromatography coupled with quadrupole Orbitrap high-resolution mass spectrometry (UHPLC Q-Orbitrap HRMS). The proposed method showed some advantages, such as multi-mycotoxin analyses with simple sample preparation, fast determination, and high sensitivity. The analysis of the sample revealed the presence of 11 mycotoxins, with α-zearalenol being the most frequently detected, while deoxynivalenol exhibited the highest contamination level. Furthermore, co-occurrence was identified in 15.5% of the samples under analysis. Among these, 13% of the samples reported the simultaneous presence of two mycotoxins, while 2.5% showed the co-occurrence of three mycotoxins. Currently, there has been a renewed interest in guaranteeing the quality and safety of products intended for human consumption. This study holds significant value due to its ability to simultaneously detect multiple mycotoxins within a complex matrix. Furthermore, it provides findings regarding the occurrence and co-occurrence of emerging mycotoxins that currently lack regulation under the existing European Commission Regulation.

The Effect of Mycotoxins and Their Mixtures on Bovine Spermatozoa Characteristics

There is growing concern about the effects of mycotoxins on mammalian reproduction. Although the effects of single mycotoxins have been well documented, the impact of their mixtures on spermatozoon quality is less known. Here, frozen-thawed semen (n = 6 bulls) was in-vitro-cultured (2 h) without (control) or with (i) a single mycotoxin [zearalenone (ZEN), ochratoxin A (OTA), toxin 2 (T2), and diacetoxyscirpenol (DAS)] in a dose-response manner; (ii) binary mixtures (OTA + T2, OTA + ZEN, OTA + DAS, ZEN + T2, DAS + T2 and ZEN + DAS); or (iii) ternary mixtures (OTA + DAS + T2, OTA + ZEN + T2, and ZEN + DAS + T2). Then, the spermatozoa quality was characterized according to its plasma- and acrosome-membrane integrity, mitochondrial membrane potential, and oxidation status by a flow cytometer. Exposure to single mycotoxins or binary mixtures did not affect the spermatozoa characteristics. However, exposure to the ternary mixtures, OTA + DAS + T2 and OTA + ZEN + T2, reduced (p < 0.05) the mitochondrial membrane potential relative to the control. In addition, OTA + ZEN + T2 increased (p < 0.05) the proportion of spermatozoa with reactive oxygen species relative to the control. The most suggested interaction effect between the mycotoxins was found to be an additive one. A synergistic interaction, mainly regarding the oxidation status of the spermatozoa, was also found between the mycotoxins. The current study sheds light on the potential risk of exposing spermatozoa to a mycotoxin mixture.

Modified Mycotoxins and Multitoxin Contamination of Food and Feed as Major Analytical Challenges

Mycotoxins, as natural products of molds, are often unavoidable contaminants of food and feed, to which the increasingly evident climate changes contribute a large part. The consequences are more or less severe and range from economic losses to worrying health problems to a fatal outcome. One of the best preventive approaches is regular monitoring of food and feed for the presence of mycotoxins. However, even under conditions of frequent, comprehensive, and conscientious controls, the desired protection goal may not be achieved. In fact, it often happens that, despite favorable analytical results that do not indicate high mycotoxin contamination, symptoms of their presence occur in practice. The most common reasons for this are the simultaneous presence of several different mycotoxins whose individual content does not exceed the detectable or prescribed values and/or the alteration of the form of the mycotoxin, which renders it impossible to be analytically determined using routine methods. When such contaminated foods enter a living organism, toxic effects occur. This article aims to shed light on the above problems in order to pay more attention to them, work to reduce their impact, and, eventually, overcome them.

The Ultrasensitive Detection of Aflatoxin M1 Using Gold Nanoparticles Modified Electrode with Fe3+ as a Probe

The increasing incidence of diseases caused by highly carcinogenic aflatoxin M₁ (AFM₁) in food demands a simple, fast, and cost-effective detection technique capable of sensitively monitoring AFM₁. Recent works predominantly focus on the electrochemical aptamer-based biosensor, which still faces challenges and high costs in experimentally identifying an efficient candidate aptamer. However, the direct electrochemical detection of AFM₁ has been scarcely reported thus far. In this study, we observed a significant influence on the electrochemical signals of ferric ions at a gold nanoparticle-modified glassy carbon electrode (AuNPs/GCE) by adding varying amounts of AFM₁. Utilizing ferricyanide as a sensitive indicator of AFM₁, we have introduced a novel approach for detecting AFM₁, achieving an unprecedentedly low detection limit of 1.6 × 10^-21 g/L. Through monitoring the fluorescence quenching of AFM₁ with Fe³⁺ addition, the interaction between them has been identified at a ratio of 1:936. Transient fluorescence analysis reveals that the fluorescence quenching process is predominantly static. It is interesting that the application of iron chelator diethylenetriaminepentaacetic acid (DTPA) cannot prevent the interaction between AFM₁ and Fe³⁺. With a particle size distribution analysis, it is suggested that a combination of AFM₁ and Fe³⁺ occurs and forms a polymer-like aggregate. Nonetheless, the mutual reaction mechanism between AFM₁ and Fe³⁺ remains unexplained and urgently necessitates unveiling. Finally, the developed sensor is successfully applied for the AFM₁ test in real samples, fully meeting the detection requirements for milk.

Determination of mycotoxins and their dietary exposure assessment in pale lager beers using immunoaffinity columns and UPLC-MS/MS

The use of contaminated raw materials can lead to the transfer of mycotoxins into the final product, including beer. This study describes the use of the commercially available immunoaffinity column 11⁺Myco MS-PREP^® and UPLC-MS/MS for the determination of mycotoxins in pale lager-type beers brewed in Czech Republic and other European countries. The additional aim of the work was to develop, optimize and validate this analytical method. Validation parameters such as linearity, limit of detection (LOD), limit of quantification (LOQ), precision and accuracy were tested. The calibration curves were linear with correlation coefficients (R² > 0.99) for all mycotoxins under investigation. The LOD ranged from 0.1 to 50 ng/L and LOQ from 0.4 to 167 ng/L. Recoveries of the selected analytes ranged from 72.2 to 101.1%, and the relative standard deviation under conditions repeatability (RSDr) did not exceed 16.3% for any mycotoxin. The validated procedure was successfully applied for the analysis of mycotoxins in a total of 89 beers from the retail network. The results were also processed using advanced chemometric techniques and compared with similar published studies. The toxicological impact was taken into account.

High throughput and automated solid-phase microextraction and determination by liquid chromatography-mass spectrometry for the analysis of mycotoxins in beer

There is high demand for rapid screening of toxics in food analysis. In this study, a new high-throughput and automated solid-phase microextraction (SPME) system was employed for the sample preparation of mycotoxins in beers. Matrix compatible SPME blades with thin coating layer were used, which significantly decreased the matrix effects in beer samples (≤ 12%). This SPME system allows 96 samples to be processed automatically and simultaneously with average preparation time of 57 s per sample. After sample preparation, the 96-well plate with desorption solution was sealed with a thin film and put into the LC-MS sampler for analysis via positive/negative ESI switching mode. The results also showed good sensitivity (limits of detection between 0.02 and 3 ng/mL) with R²≥ 0.9971, reproducibility (intra- and inter-day ≤ 8% and ≤ 13%, respectively), and accuracy (recoveries between 79% and 121%).

Extraction and characterization of bioactive secondary metabolites from lactic acid bacteria and evaluating their antifungal and antiaflatoxigenic activity

Aflatoxins are toxic carcinogens and mutagens formed by some moulds, specifically Aspergillus spp. Therefore, this study aimed to extract and identify bioactive secondary metabolites from Lactobacillus species, to evaluate their efficacy in reducing fungal growth and aflatoxin production and to investigate their toxicity. The bioactive secondary metabolites of Lactobacillus species showed variable degrees of antifungal activity, whereas L. rhamnosus ethyl acetate extract No. 5 exhibited the highest antifungal activity and, thus, was selected for further identification studies. Data revealed that L. rhamnosus ethyl acetate extract No. 5 produced various organic acids, volatile organic compounds and polyphenols, displayed antifungal activity against A. flavus, and triggered morphological changes in fungal conidiophores and conidiospores. L. rhamnosus ethyl acetate extract No. 5 at a 9 mg/mL concentration reduced AFB₁ production by 99.98%. When the effect of L. rhamnosus ethyl acetate extract No. 5 on brine shrimp mortality was studied, the extract attained a 100% mortality at a concentration of 400 µg/mL, with an IC₅₀ of 230 µg/mL. Meanwhile, a mouse bioassay was performed to assess the toxicity of L. rhamnosus ethyl acetate extract No. 5, whereas there were no harmful effects or symptoms in mice injected with L. rhamnosus ethyl acetate extract at concentrations of 1, 3, 5, 7, and 9 mg/kg body weight.

Rapid and quantitative determination of deoxynivalenol in cereal through the combination of magnetic solid-phase extraction and optical fiber-based homogeneous chemiluminescence immunosensor

An integrated strategy for the rapid and sensitive detection of deoxynivalenol in cereals was developed by combining Fe₃O₄ magnetic nanoparticle-modified metal organic framework-5-based magnetic solid-phase extraction and the optical fiber-based homogeneous chemiluminescence immunosensor. The hybrid magnetic material was prepared and characterized, exhibiting good enrichment capacity up to 1.68 mg/g. The competitive immunoassay-based homogeneous chemiluminescence immunosensor enabled washing-free and high-sensitivity detection of deoxynivalenol. Under optimized conditions, this immunosensor could detect deoxynivalenol as low as 46.7 pg/mL with a quantitatively linear range of 0.1 to 1000 ng/mL. The recoveries of this integrated detection strategy in rice, corn, and wheat ranged from 80.0 % to 118.2 %, 91.1 % to 116.7 %, and 80.0 % to 91.5 %, respectively, with a relative standard deviation that did not exceed 9.11 %. More importantly, it shows great consistency with the high-performance liquid chromatography-mass spectrometry in blind sample analysis. This integrated detection strategy provides a convenient approach for mycotoxins screening in cereals.

An aptamer-functionalized photonic crystal sensor for ultrasensitive and label-free detection of aflatoxin B1

As a novel optical responsive material, photonic crystal is a promising sensing material in the recognition and detection of small molecules. Herein, a label-free composite sensor for aflatoxin B1 (AFB1) based on aptamer-functionalized photonic crystal arrays was successfully developed. Three-dimensional photonic crystals (3D PhCs) with a controllable number of layers were produced by a layer-by-layer (LBL) approach, and the introduction of gold nanoparticles (AuNPs) facilitated the immobilization procedure of recognition element aptamers, thus creating the AFB1 sensing detection system (AFB1-Apt 3D PhCs). The sensing system AFB1-Apt 3D PhCs exhibited a good linearity in the wide range of 1 pg mL^-1-100 ng mL^-1 AFB1 with a limit of detection (LOD) of 0.28 pg mL^-1. Furthermore AFB1-Apt 3D PhC was successfully applied in the determination of AFB1 in the millet and beer samples with good recovery. The sensing system performed ultrasensitive and label-free detection to the target, which could be further applied in the fields of food safety, clinical diagnosis or environmental monitoring, establishing an efficient and rapid universal detection platform.

Recent Insights into Sample Pretreatment Methods for Mycotoxins in Different Food Matrices: A Critical Review on Novel Materials

Mycotoxins pollution is a global concern, and can pose a serious threat to human health. People and livestock eating contaminated food will encounter acute and chronic poisoning symptoms, such as carcinogenicity, acute hepatitis, and a weakened immune system. In order to prevent or reduce the exposure of human beings and livestock to mycotoxins, it is necessary to screen mycotoxins in different foods efficiently, sensitively, and selectively. Proper sample preparation is very important for the separation, purification, and enrichment of mycotoxins from complex matrices. This review provides a comprehensive summary of mycotoxins pretreatment methods since 2017, including traditionally used methods, solid-phase extraction (SPE)-based methods, liquid-liquid extraction (LLE)-based methods, matrix solid phase dispersion (MSPD), QuEChERS, and so on. The novel materials and cutting-edge technologies are systematically and comprehensively summarized. Moreover, we discuss and compare the pros and cons of different pretreatment methods and suggest a prospect.

Recent Advances in Mycotoxin Determination in Fish Feed Ingredients

Low-cost plant-based sources used in aquaculture diets are prone to the occurrence of animal feed contaminants, which may in certain conditions affect the quality and safety of aquafeeds. Mycotoxins, a toxic group of small organic molecules produced by fungi, comprise a frequently occurring plant-based feed contaminant in aquafeeds. Mycotoxin contamination can potentially cause significant mortality, reduced productivity, and higher disease susceptibility; thus, its timely detection is crucial to the aquaculture industry. The present review summarizes the methodological advances, developed mainly during the past decade, related to mycotoxin detection in aquafeed ingredients, namely analytical, chromatographic, and immunological methodologies, as well as the use of biosensors and spectroscopic methods which are becoming more prevalent. Rapid and accurate mycotoxin detection is and will continue to be crucial to the food industry, animal production, and the environment, resulting in further improvements and developments in mycotoxin detection techniques.

How different microfilters affect the recovery of eleven EU-regulated mycotoxins

Microfiltration is a common step in liquid chromatography - tandem mass spectrometry (LC-MS), a method of choice in determining several mycotoxins in a solution at once. However, microfiltration may entail filter-analyte interactions that can affect the accuracy of the procedure, and underestimate exposure. The aim of our study was to assess how five different membrane materials for syringe filters (nylon, polytetrafluoroethylene, polyethersulphone, mixed cellulose ester, and cellulose acetate) affect microfiltration and recovery of EU-regulated mycotoxins, including aflatoxins B1, B2, G1, and G2, deoxynivalenol, fumonisins B1 and B2, zearalenone, T-2 and HT-2 toxins, and ochratoxin A. Polytetrafluoroethylene filters turned out to least affect microfiltration through mycotoxin loss, followed by more commonly used nylon filters, whereas the remaining three filter membrane materials had such a negative effect on recoveries that we found them incompatible with the procedure. Our findings clearly suggest that it is important to select a proper filter type that suits analyte properties and solution composition and to discard the first few filtrate drops to ensure the accuracy of the analytical procedure.

Determination of Regulated and Emerging Mycotoxins in Organic and Conventional Gluten-Free Flours by LC-MS/MS

Gluten-free cereal products have grown in popularity in recent years as they are perceived as "healthier" alternatives and can be safely consumed by celiac patients, and people with gluten intolerance or wheat allergies. Molds that produce mycotoxins contaminate cereal crops, posing a threat to global food security. Maximum levels have been set for certain mycotoxins in cereal flours; however, little is known about the levels of emerging mycotoxins in these flours. The aim of this study was to develop an efficient, sensitive, and selective method for the detection of four emerging (beauvericin and enniatins A1, B, and B1) and three regulated (aflatoxin B1, zearalenone, and deoxynivalenol) mycotoxins in gluten-free flours. Ultrasound-assisted matrix solid-phase dispersion was used in the extraction of these mycotoxins from flour samples. The validated method was utilized for the LC-MS/MS analysis of conventional and organic wholegrain oat and rice flours. Six of the seven target mycotoxins were detected in these samples. Multi-mycotoxin contamination was found in all flour types, particularly in conventional wholegrain oat flour. Despite the low detection frequency in rice flour, one sample was found to contain zearalenone at a concentration of 83.2 μg/kg, which was higher than the level set by the European Commission for cereal flours. The emerging mycotoxins had the highest detection frequencies; enniatin B was present in 53% of the samples at a maximum concentration of 56 μg/kg, followed by enniatin B1 and beauvericin, which were detected in 46% of the samples, and at levels reaching 21 μg/kg and 10 μg/kg, respectively. These results highlight the need to improve the current knowledge and regulations on the presence of mycotoxins, particularly emerging ones, in gluten-free flours and cereal-based products.

Current Developments of Analytical Methodologies for Aflatoxins' Determination in Food during the Last Decade (2013-2022), with a Particular Focus on Nuts and Nut Products

This review aims to provide a clear overview of the most important analytical development in aflatoxins analysis during the last decade (2013-2022) with a particular focus on nuts and nuts-related products. Aflatoxins (AFs), a group of mycotoxins produced mainly by certain strains of the genus Aspergillus fungi, are known to impose a serious threat to human health. Indeed, AFs are considered carcinogenic to humans, group 1, by the International Agency for Research on Cancer (IARC). Since these toxins can be found in different food commodities, food control organizations worldwide impose maximum levels of AFs for commodities affected by this threat. Thus, they represent a cumbersome issue in terms of quality control, analytical result reliability, and economical losses. It is, therefore, mandatory for food industries to perform analysis on potentially contaminated commodities before the trade. A full perspective of the whole analytical workflow, considering each crucial step during AFs investigation, namely sampling, sample preparation, separation, and detection, will be presented to the reader, focusing on the main challenges related to the topic. A discussion will be primarily held regarding sample preparation methodologies such as partitioning, solid phase extraction (SPE), and immunoaffinity (IA) related methods. This will be followed by an overview of the leading analytical techniques for the detection of aflatoxins, in particular liquid chromatography (LC) coupled to a fluorescence detector (FLD) and/or mass spectrometry (MS). Moreover, the focus on the analytical procedure will not be specific only to traditional methodologies, such as LC, but also to new direct approaches based on imaging and the ability to detect AFs, reducing the need for sample preparation and separative techniques.

Type B Trichothecenes in Cereal Grains and Their Products: Recent Advances on Occurrence, Toxicology, Analysis and Post-Harvest Decontamination Strategies

Type B trichothecenes (deoxynivalenol, nivalenol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol) and deoxynivalenol-3-glucoside (DON-3G) are secondary toxic metabolites produced mainly by mycotoxigenic Fusarium fungi and have been recognized as natural contaminants in cereals and cereal-based foods. The latest studies have proven the various negative effects of type B trichothecenes on human health. Due to the widespread occurrence of Fusarium species, contamination by these mycotoxins has become an important aspect for public health and agro-food systems worldwide. Hence, their monitoring and surveillance in various foods have received a significant deal of attention in recent years. In this review, an up-to-date overview of the occurrence profile of major type B trichothecenes and DON-3G in cereal grains and their toxicological implications are outlined. Furthermore, current trends in analytical methodologies for their determination are overviewed. This review also covers the factors affecting the production of these mycotoxins, as well as the management strategies currently employed to mitigate their contamination in foods. Information presented in this review provides good insight into the progress that has been achieved in the last years for monitoring type B trichothecenes and DON-3G, and also would help the researchers in their further investigations on metabolic pathway analysis and toxicological studies of these Fusarium mycotoxins.

Establishment and application of a screening method for 354 organic toxicants in blood and urine with high-performance liquid chromatography-high-resolution orbitrap mass spectrometry

A rapid and sensitive high-performance liquid chromatography-high-resolution orbitrap mass spectrometry method was developed for the simultaneous screening of 354 organic poisons and metabolites in blood and urine, including drugs, medications, pesticides, rodenticides, veterinary drugs, alkaloids, and mycotoxins with a multi-toxicant chromatography-mass spectrometry information library. The method and library showed good prospects in clinical poisoning screening and forensic toxicological identification. Blood and urine samples were extracted successively with ethyl acetate in acidic and alkaline conditions; then, the extract was blown to nearly dry by nitrogen gas and redissolved with methanol-aqueous solution (v:v, 50:50), and the dissolved solution was analyzed by LC-MS/MS after filtering. Precursor ions' m/z was set for identification, retention time, fragment ions, and isotopic pattern which were used for confirmation. No interference peaks were found in the blank samples, showing good specificity. The LODs of toxicants in urine and blood were 1.00×10^-3-50.0 ng/mL and 2.07×10^-3-50.0 ng/mL, respectively, while the LOQs were 3.30×10^-3-1.67×10² ng/mL and 6.91×10^-3-1.67×10² ng/mL. The intra-day precision and inter-day precision of urine samples were 2.31-9.13% and 4.75-12.3%, respectively, which were 1.92-10.8% and 2.01-12.1% in blood samples. The established method was applied to analyze 9 cases of clinical poisoning patients, and bromadiolone, carbofuran, and amanitins were detected, respectively. A total of 382 biospecimens from drug abusers were analyzed with the proposed method, which indicated that some drugs were detected in 62 cases, mainly including methamphetamine, heroin, and MDMA. The results were consistent with the information from traditional liquid chromatography-triple quadrupole mass spectrometry.

Production of Aflatoxin B1 by Aspergillus parasiticus Grown on a Novel Meat-Based Media

The aim of the present study was to develop meat-based media with compositions similar to those of dry-fermented meat products and to evaluate their use in studying the growth of Aspergillus parasiticus and the kinetics of aflatoxin B1 (AFB1) production. In our previous experiments, we found that the strain A. parasiticus ŽMJ7 produced a high amount of AFB1. Cooked meat agar (CMA2) was used as a novel complex meat-based medium with four variations: CMA2G (CMA2 supplemented with 1% glucose), CMA2YE (CMA2 supplemented with 0.2% yeast extract), and CMA2GYE (CMA2 supplemented with 1% glucose and 0.2% yeast extract). Media were inoculated with an A. parasiticus spore suspension (105 spores/mL) and incubated at 25 °C for up to 15 days. The A. parasiticus lag phase lasted less than 1 day, irrespective of the growth medium, with the exception of control medium CMA1 (cooked meat agar) as an already known meat-based medium. The highest mean colony growth rate was observed on CMA2 and CMA2G. Reversed-phase UPLC-MS/MS analysis was performed to determine the AFB1 concentration in combination with solid phase extraction (SPE). The highest AFB1 concentration in meat-based media was detected in CMA2GYE after 15 days of incubation (13,502 ± 2367 ng/mL media). The results showed that for studying AFB1 production in dry-fermented meat products, novel suitable media such as CMA2-based media are required. This finding could represent a potential concern with regard to the production of dry-fermented meat products.

Optimizing extraction solvents for deoxynivalenol analysis in maize via infrared attenuated total reflection spectroscopy and chemometric methods

Farmers, cereal suppliers and processors demand rapid techniques for the assessment of mould-associated contamination. Deoxynivalenol (DON) is among the most important Fusarium toxins and related to human and animal diseases besides causing significant economic losses. Routine analytical techniques for the analysis of DON are either based on chromatographic or immunoanalytical techniques, which are time-consuming and frequently rely on hazardous consumables. The present study evaluates the feasibility of infrared attenuated total reflection spectroscopy (IR-ATR) for the analysis of maize extracts via different solvents optimized for the determination of DON contamination along the regulatory requirements by the European Union (EU) for unprocessed maize (1750 μg kg^-1). Reference analysis was done by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The studied maize samples were either naturally infected or had been artificially inoculated in the field with Fusarium graminearum, Fusarium culmorum or Fusarium verticillioides. Principal component analysis demonstrated that water and methanol-water (70 : 30% v) were optimum solvents for differentiating DON contamination levels. Supervised partial least squares discriminant analysis resulted in excellent classification accuracies of 86.7% and 90.8% for water and methanol-water extracts, respectively. The IR spectra of samples with fungal infection and high DON contamination had distinct spectral features, which could be related to carbohydrates, proteins and lipid content within the investigated extracts.

Natural Deep Eutectic Solvents (NADESs) Combined with Sustainable Extraction Techniques: A Review of the Green Chemistry Approach in Food Analysis

Usual extraction processes for analyzing foods, supplements, and nutraceutical products involve massive amounts of organic solvents contributing to a negative impact on the environment and human health. In recent years, a new class of green solvents called natural deep eutectic solvents (NADES) have been considered a valid alternative to conventional solvents. Compared with conventional organic solvents, NADES have attracted considerable attention since they are sustainable, biodegradable, and non-toxic but also are easy to prepare, and have low production costs. Here we summarize the major aspects of NADEs such as the classification, preparation method physicochemical properties, and toxicity. Moreover, we provide an overview of novel extraction techniques using NADES as potential extractants of bioactive compounds from foods and food by-products, and application of NADEs in food analysis. This review aims to be useful for the further development of NAES and for broadening the knowledge of these new green solvents in order to increase their use for the extraction of bioactive compounds and in food analysis.

The Effect of Aflatoxin B1 on Tumor-Related Genes and Phenotypic Characters of MCF7 and MCF10A Cells

The fungal toxin aflatoxin B1 (AB1) and its reactive intermediate, aflatoxin B1-8, 9 epoxide, could cause liver cancer by inducing DNA adducts. AB1 exposure can induce changes in the expression of several cancer-related genes. In this study, the effect of AB1 exposure on breast cancer MCF7 and normal breast MCF10A cell lines at the phenotypic and epigenetic levels was investigated to evaluate its potential in increasing the risk of breast cancer development. We hypothesized that, even at low concentrations, AB1 can cause changes in the expression of important genes involved in four pathways, i.e., p53, cancer, cell cycle, and apoptosis. The transcriptomic levels of BRCA1, BRCA2, p53, HER1, HER2, cMyc, BCL2, MCL1, CCND1, WNT3A, MAPK1, MAPK3, DAPK1, Casp8, and Casp9 were determined in MCF7 and MCF10A cells. Our results illustrate that treating both cells with AB1 induced cytotoxicity and apoptosis with reduction in cell viability in a concentration-dependent manner. Additionally, AB1 reduced reactive oxygen species levels. Phenotypically, AB1 caused cell-cycle arrest at G1, hypertrophy, and increased cell migration rates. There were changes in the expression levels of several tumor-related genes, which are known to contribute to activating cancer pathways. The effects of AB1 on the phenotype and epigenetics of both MCF7 and MCF10A cells associated with cancer development observed in this study suggest that AB1 is a potential risk factor for developing breast cancer.

Simultaneous determination of twelve mycotoxins in edible oil, soy sauce and bean sauce by PRiME HLB solid phase extraction combined with HPLC-Orbitrap HRMS

A solid phase extraction-high-performance liquid chromatography-tandem Orbitrap high resolution mass spectrometry (HPLC-Orbitrap HRMS) method was established for the determination of 12 mycotoxins (ochratoxin A, ochratoxin B, aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, HT-2 toxin, sterigmatocystin, diacetoxysciroenol, penicillic acid, mycophenolic acid, and citreoviridin) in edible oil, soy sauce, and bean sauce. Samples were extracted by 80:20 (v:v) acetonitrile-water solution, purified by PRiME HLB column, separated by aQ C18 column with mobile phase consisting of 0.5 mmol/L ammonium acetate-0.1% formic acid aqueous solution and methanol. The results showed that the limits of detection (LODs) and limits of quantification (LOQs) of 12 mycotoxins were 0.12–1.2 μg/L and 0.40–4.0 μg/L, respectively. The determination coefficients of 12 mycotoxins in the range of 0.20–100 μg/L were &gt; 0.998. The average recoveries in soy sauce and bean sauce were 78.4–106.8%, and the relative standard deviations (RSDs) were 1.2–9.7% under three levels, including LOQ, 2× LOQ and 10 × LOQ. The average recoveries in edible oil were 78.3–115.6%, and the precision RSD (n = 6) was 0.9–8.6%. A total of 24 edible oils, soy sauce and bean sauce samples were analyzed by this method. AFB1, AFB2, sterigmatocystin and mycophenolic acid were detected in several samples at concentrations ranging from 1.0 to 22.1 μg/kg. The method is simple, sensitive, and rapid and can be used for screening and quantitative analysis of mycotoxin contamination in edible oil, soy sauce, and bean sauce.

Co-occurrence of mycotoxins: A review on bioanalytical methods for simultaneous analysis in human biological samples, mixture toxicity and risk assessment strategies

Mycotoxins are the toxic chemical substances that are produced by various fungal species and some of these are harmful to humans. Mycotoxins are ubiquitous in nature and humans could be exposed to multiple mycotoxins simultaneously. Unfortunately, exposure to mixed mycotoxins is not very well studied. Various studies have demonstrated the capacity of mycotoxins to show synergistic effect in the presence of other mycotoxins, thus, increasing the risk of toxicity. Hence, it is important to monitor mixed mycotoxins in human biological samples which would serve as a crucial information for risk assessment. Through this review paper, we aim to summarize the mixture toxicity of mycotoxins and the various bio-analytical techniques that are being used for the simultaneous analysis of mixed mycotoxins in human biological samples. Different sample preparation and clean-up techniques employed till date for eliminating the interferences from human biological samples without affecting the analyses of the mycotoxins are also discussed. Further, a brief introduction of risk assessment strategies that have been or could be adopted for multiple mycotoxin risk assessments is also mentioned. To the best of our knowledge, this is the first review that focuses solely on the occurrence of multiple mycotoxins in human biological samples as well as their risk assessment strategies.

Effect of roasting and frying treatments on aflatoxins and capsaicinoids content and nutritional profile of green chilies ( Capsicum annum L.)

This study was conducted to assess the effect of two thermal treatments, viz. roasting and pan frying (deep frying), on nutritional profile, aflatoxin, and capsaicin content in green chilies. Green chilies were subjected to roasting and frying to reduce the aflatoxin contamination, besides retaining their pungency and nutritional profile. Reversed‐phase HPLC was employed to determine the levels of aflatoxins B1, B2, G1, and G2 in thermally treated and control samples. The proximate compositions of roasted and fried chili samples were significantly (p ≤ .05) different from raw chili (control), except ash content. Vitamin A levels decreased significantly (p ≤ .05) during roasting and were undetected in fried chili samples. Likewise, vitamin C was undetected in both roasted and fried chili samples. Significantly decreasing (p ≤ .05) trends were noticed in capsaicinoids viz. capsaicin and dihydrocapsaicin contents including Scoville Heat Units (SHU) during roasting and frying. However, retention of capsaicinoids was higher in roasted chilies (730.00 ± 4.90 mg/kg) than fried samples (502.56 ± 5.10 mg/kg). The levels of all the four major aflatoxins (AFs)‐ AFB1, AFB2, AFG1, and AFG2 recorded in control were much higher than the limits prescribed by the European Union for spices. Both thermal treatments (roasting and frying) employed proved to be effective in reducing aflatoxins like AFB2, AFG1, and AFG2 in chilies to below the prescribed limits, while as the level of AFB1 was reduced below the limits by only the frying method. This study therefore indicated the substantial impact of frying on aflatoxins.

Mycotoxins of Concern in Children and Infant Cereal Food at European Level: Incidence and Bioaccessibility

Cereals are of utmost importance for the nutrition of infants and children, as they provide important nutrients for their growth and development and, in addition, they are easily digestible, being the best choice for the transition from breast milk/infant formula to solid foods. It is well known that children are more susceptible than adults to toxic food contaminants, such as mycotoxins, common contaminants in cereals. Many mycotoxins are already regulated and controlled according to strict quality control standards in Europe and around the world. There are, however, some mycotoxins about which the level of knowledge is lower: the so-called emerging mycotoxins, which are not yet regulated. The current review summarizes the recent information (since 2014) published in the scientific literature on the amounts of mycotoxins in infants’ and children’s cereal-based food in Europe, as well as their behaviour during digestion (bioaccessibility). Additionally, analytical methods used for mycotoxin determination and in vitro methods used to evaluate bioaccessibility are also reported. Some studies demonstrated the co-occurrence of regulated and emerging mycotoxins in cereal products used in children’s food, which highlights the need to adopt guidelines on the simultaneous presence of more than one mycotoxin. Although very little research has been done on the bioaccessibility of mycotoxins in these food products, very interesting results correlating the fiber and lipid contents of such products with a higher or lower bioaccessibility of mycotoxins were reported. LC-MS/MS is the method of choice for the detection and quantification of mycotoxins due to its high sensibility and accuracy. In vitro static digestion models are the preferred ones for bioaccessibility evaluation due to their simplicity and accuracy.

Spatial barcoding-enabled highly multiplexed immunoassay with digital microfluidics

Digital microfluidics (DMF), facilitating independent manipulation of microliter samples, provides an ideal platform for immunoassay detection; however, suffering limited multiplexity. To address the need, herein we described a digital microfluidics (DMF) platform that realizes spatial barcoding on the Teflon-coated indium tin oxide (ITO) glass side to fulfill highly multiplexed immunoassay (10+) with low-volume samples (∼4 μL) in parallel, representing the highest multiplexing recorded to date for DMF-actuated immunoassay. Planar-based spatial immobilization of multiple capture antibodies was realized on a Teflon-coated ITO glass side, which was then used as the top plate of the DMF device. Droplets containing analytes, secondary antibodies, and fluorescent signaling reporters with low volume, which were electrically manipulated by our DMF control system, were shuttled sequentially along the working electrodes to complete the immuno-reaction. Evaluation of platform performance with recombinant proteins showed excellent sensitivity and reproducibility. To test the feasibility of our platform in analyzing multiplex biomarkers of the immune response, we used lipopolysaccharide-stimulated macrophages as a model system for protein secretion dynamics studies. As a result, temporal profiling of pro-inflammatory cytokine secretion dynamics was obtained. The spatial barcoding strategy presented here is easy-to-operate to enable a more comprehensive evaluation of protein abundance from biological samples, paving the way for new opportunities to realize multiplexity-associated applications with the DMF platform.

Determination of aflatoxin B1 in Pixian Douban based on aptamer magnetic solid-phase extraction

Aflatoxin B1 (AFB₁) is considered as the most prevalent and toxic mycotoxin in food, and is the indispensable index in the monitoring of Pixian Douban, a traditional chinese fermented bean paste from Sichuan. However, the effeciency of AFB₁ detection in Pixian Douban is influenced by the traditional extraction, which is usually complex and time consuming. Therefore, an aptamer-based magnetic solid-phase extraction method was designed for the pretreatment of AFB₁ in this sample, for which Fe₃O₄ was synthesized via the solvothermal method and then a Fe₃O₄@SiO₂–NH₂ with a core–shell structure was prepared, followed by an AFB₁-aptamer attachment. The validation was performed via an enzyme-linked immunosorbent assay and compared with HPLC-MS/MS. The linearity range of this method was 0.5–2.0 ng mL ⁻¹ with R² of 0.981, and recoveries of AFB₁ ranged from 80.19% to 113.92% with RSDs below 7.28% with no significant differences compared to HPLC-MS/MS. The three-time reusability efficiencies of aptamer-MNPs were averaged at 78.24%. The results proved that aptamer-MNPs were high-performance adsorbents for extracting and enriching AFB₁, facilitating quick and effective detection of AFB₁ in Pixian DouBan samples.

An aptamer-based magnetic solid-phase extraction method was designed for the pretreatment of AFB1 from a Pixian Douban sample. It was developed based on aptamer–Fe₃O₄@SiO₂–NH₂ with subsequent ELISA validation, showing an efficient result.

Development and Validation of an UHPLC-MS/MS Method for the Simultaneous Determination of 11 EU-Regulated Mycotoxins in Selected Cereals

The availability of reliable sensitive multi-analyte methods for unambiguous determination of mycotoxins is crucial for ensuring food and feed safety, considering their adverse health effects and (co-)occurrence in various foods. Accordingly, a multi-mycotoxin confirmatory method for simultaneous determination of 11 mycotoxins regulated in cereals within the European Union (EU) using ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) was developed and in-house validated to fit the EU legislation requirements for analytical methods. A simple sample preparation was based on a solid−liquid extraction using a solvent mixture acetonitrile/water/formic acid (79/20/1, v/v/v) and a dilution of raw extract using water/acetonitrile/formic acid (79/20/1, v/v/v) before instrumental analysis. Average recoveries in all three validated cereal crop types (maize, wheat, and barley), spiked at multiple levels, were found acceptable for all analytes when matrix-matched calibration was used, ranging from 63.2% to 111.2% and also showing very good repeatability, with relative standard deviations below 20%. Matrix effect (SSE) evaluation revealed maize as the most complex of the three analyzed cereal matrices, with strong SSE (<50% and >150%) recorded for all 11 analyzed mycotoxins. An additional method verification was performed through successful participation in proficiency testing schemes, with the achieved z-scores generally in the acceptable range of −2 ≤ z ≤ 2. The obtained validation results demonstrated the suitability of the developed confirmatory multi-mycotoxin UHPLC-MS/MS method based on a dilute-and-shoot principle for the simultaneous determination of low concentrations of 11 EU-regulated mycotoxins in cereals, including aflatoxins B1, B2, G1 and G2, deoxynivalenol, fumonisins B1 and B2, zearalenone, T-2 and HT-2 toxins, and ochratoxin A.

Quantitative analysis of metabolites in the aflatoxin biosynthesis pathway for early warning of aflatoxin contamination by UHPLC-HRMS combined with QAMS

Aflatoxins seriously threaten human health and food safety, and early warning benefits the reasonable use of control measures to reduce aflatoxin contamination. In this study, a novel method for quantifying aflatoxins and their precursors in the aflatoxin biosynthesis pathway was developed by combining ultra-high performance liquid chromatography high-resolution mass spectrometry (UHPLC-HRMS) with quantitative analysis of multi-components by a single marker (QAMS). The stability of the relative correction factor (RCF) of QAMS was then systematically evaluated. The validation results showed that the relative deviation (RD) between QAMS and the external standard method (ESM) was less than 11.7%, indicating that the established QAMS method could replace ESM without the use of reference standards. This method was successfully employed to compare the time-course changes of metabolites in the aflatoxin biosynthesis pathway of Aspergillus flavus and Aspergillus parasitica. As a result, the precursors of (1'S,5'R)-5'-Hydroxyaverantin (HAVN) and Versicolorin B (VerB) could be used as potential markers for the early warning of aflatoxin contamination. This study provided a quantitative method of aflatoxins and their precursors in the biosynthesis pathway, and may serve as a reference for the extension of quantitative studies on other metabolic pathways.