Determination of mycotoxins in feedstuffs and ruminant׳s milk using an easy and simple LC–MS/MS multiresidue method

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.

LC-MS/MS and GC-MS based phytochemical perspectives and antimicrobial effects of endophytic fungus Chaetomium ovatoascomatis isolated from Euphorbia milii

The antimicrobial activity of endophytic fungi isolated from Euphorbia milii was evaluated against Gram-positive, Gram-negative bacteria, unicellular yeast, and filamentous fungi. Chaetomium ovatoascomatis NRC was identified morphologically and genetically as the most active strain. The total ethyl acetate extract of C. ovatoascomatis NRC demonstrated significant antimicrobial activity against Gram-negative; Escherichia coli, Salmonella enteric, and fungi; Aspergillus niger with MIC of 62.5 ug/ml. Whereas n-hexane fraction demonstrated broader activity against Gram-positive; Bacillus subtilis, Lactobacillus cereus, Gram-negative; Escherichia coli and Salmonella enteric, fungi; Candida albicans and F. solani. LC–MS/MS analysis of ethyl acetate strain extract and GC–MS analysis of the n-hexane fraction were used to identify the metabolites of the strain extract. LC–MS/MS determined three major metabolites with potential antimicrobial activities including grevilline B, aflatoxin G2 and apigenin. GC–MS analysis of n-hexane fraction tentatively identified 30 compounds, where 9,12-octadecadienoic acid methyl ester was the major compound.

Recent Progress on Techniques in the Detection of Aflatoxin B1 in Edible Oil: A Mini Review

Contamination of agricultural products and foods by aflatoxin B1 (AFB1) is becoming a serious global problem, and the presence of AFB1 in edible oil is frequent and has become inevitable, especially in underdeveloped countries and regions. As AFB1 results from a possible degradation of aflatoxins and the interaction of the resulting toxic compound with food components, it could cause chronic disease or severe cancers, increasing morbidity and mortality. Therefore, rapid and reliable detection methods are essential for checking AFB1 occurrence in foodstuffs to ensure food safety. Recently, new biosensor technologies have become a research hotspot due to their characteristics of speed and accuracy. This review describes various technologies such as chromatographic and spectroscopic techniques, ELISA techniques, and biosensing techniques, along with their advantages and weaknesses, for AFB1 control in edible oil and provides new insight into AFB1 detection for future work. Although compared with other technologies, biosensor technology involves the cross integration of multiple technologies, such as spectral technology and new nano materials, and has great potential, some challenges regarding their stability, cost, etc., need further studies.

Analysis of Aflatoxins, Fumonisins, Deoxynivalenol, Ochratoxin A, Zearalenone, HT-2, and T-2 Toxins in Animal Feed by LC-MS/MS Using Cleanup with a Multi-Antibody Immunoaffinity Column

BACKGROUND

Regulations limiting aflatoxin levels in animal feed and guidance values for maximum levels for fumonisins (FB1 and FB2), deoxynivalenol (DON), ochratoxin A (OTA), zearalenone (ZON), HT-2, and T-2 toxins are in place both to protect animal health and to minimize potential transfer to animal products for human consumption. A multi-mycotoxin method which can handle complex feed matrices such as distillers dried grains with solubles (DDGS) is essential for analysis and accurate quantification without the need to revert to separately analyze individual mycotoxins.

OBJECTIVE

The objective of this study is to generate single laboratory validation data for a method employing a multi-antibody immunoaffinity column (IAC) capable of providing cleanup for eleven mycotoxins, followed by LC-MS/MS quantification without the need for isotopic labelled and matrix-matched standards. The applicability of method is to be demonstrated for corn feed, pig feed, and DDGS by fortification and naturally occurring mycotoxins covering the range of regulated limits.

METHODS

Feed sample (1 kg) ground by milling to approximately 1-2 mm particle size and sub-sample (5 g) extracted with acetonitrile-water-formic acid, passing through a multi-mycotoxin IAC, washing, and eluting prior to LC-MS/MS analysis monitoring selected ion transitions.

RESULTS

Recoveries were in the range 74 to 117% (excluding five outliers) for aflatoxins, FB1, FB2, DON, OTA, ZON, HT-2, and T2- toxins spiked into three commercial animal feed matrixes (n = 84) and within-day RSDs averaged 1.7 to 10.3% (n = 99).

CONCLUSION

Single laboratory validation of a multi-antibody IAC method coupled with LC-MS/MS has shown the method to be suitable for accurate quantification of eleven regulated mycotoxins in DDGS, pig feed, and poultry feed.

HIGHLIGHTS

IAC method capable of accurately quantifying eleven regulated mycotoxins in complex feed matrices.

Multianalyte method for the determination of regulated, emerging and modified mycotoxins in milk: QuEChERS extraction followed by UHPLC-MS/MS analysis

A simple method for the quantification of 40 mycotoxins in milk was developed. This method is based on a QuEChERS extraction followed by the ultra-high liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) detection, and allows the simultaneous analysis of regulated, emerging, and modified mycotoxins. A sample treatment procedure was optimized to include a concentration step for the analysis of some compounds such as aflatoxin M₁. The method was in-house validated in terms of limits of detection (LODs), limits of quantification (LOQs), linearity, recoveries, and precision. LOQs lower than 10 ng/mL were obtained, and recoveries ranged from 61% to 120% with a precision, expressed as the relative standard deviation, lower than 15%. Therefore, acceptable performance characteristics were obtained fulfilling European regulations. The method was successfully applied for the quantification of mycotoxins in raw milk. It can be highlighted high occurrence of beauvericin and enniatins were found in low amounts.

Multi-Mycotoxin Contamination of Maize Silages in Flanders, Belgium: Monitoring Mycotoxin Levels from Seed to Feed

Maize silage, which in Europe is the main feed for dairy cattle in winter, can be contaminated by mycotoxins. Mycotoxigenic Fusarium spp. originating from field infections may survive in badly sealed silages or re-infect at the cutting edge during feed-out. In this way, mycotoxins produced in the field may persist during the silage process. In addition, typical silage fungi such as Penicillium spp. and Aspergillus spp. survive in silage conditions and produce mycotoxins. In this research, 56 maize silages in Flanders were sampled over the course of three years (2016-2018). The concentration of 22 different mycotoxins was investigated using a multi-mycotoxin liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, and the presence of DNA of three Fusarium spp. (F. graminearum, F. culmorum and F. verticillioides) was analyzed in a selection of these samples using quantitative polymerase chain reaction (qPCR). Every maize silage contained at least two different mycotoxins. Nivalenol (NIV) and deoxynivalenol (DON) were the most prevalent (both in 97.7% of maize silages), followed by ENN B (88.7%). Concentrations often exceeded the EU recommendations for DON and zearalenone (ZEN), especially in 2017 (21.3% and 27.7% of the maize silages, respectively). No correlations were found between fungal DNA and mycotoxin concentrations. Furthermore, by ensiling maize with a known mycotoxin load in a net bag, the mycotoxin contamination could be monitored from seed to feed. Analysis of these net bag samples revealed that the average concentration of all detected mycotoxins decreased after fermentation. We hypothesize that mycotoxins are eluted, degraded, or adsorbed during fermentation, but certain badly preserved silages are prone to additional mycotoxin production during the stable phase due to oxygen ingression, leading to extremely high toxin levels.

Mycotoxins in food: a review on liquid chromatographic methods coupled to mass spectrometry and their experimental designs

The development of a multi-mycotoxins method using LC-MS/MS is necessary and it is clear that the development of such method involves many compromises in the choice of the different parameters. This review summarizes applications using conventional experimental designs and some recent studies using response surface methodology (RSM) as a mathematical modeling tool for the optimization of extraction procedures. The authors also discuss pros and cons of the different procedures. To our knowledge, it is the first review on experimental design for the development of multi-mycotoxin methods. This review could be useful in the development and optimization of LC-MS/MS methods with the aim of describing experimental design and variables (factors) that are likely to affect sensitivity and specificity.

Combined (d)SPE-QuEChERS Extraction of Mycotoxins in Mixed Feed Rations and Analysis by High Performance Liquid Chromatography-High-Resolution Mass Spectrometry

The objective of this work was the development of a methodology capable of simultaneously determine 26 mycotoxins in mixed feed rations collected in 20 dairy farms. A sample preparation methodology based on a combination of (d)SPE and QuEChERS extractions was used. Liquid chromatography-high resolution mass spectrometry was employed for both identification and quantification purposes. To this respect, a powerful workflow based on data-independent acquisition, consisting of fragmenting all precursor ions entering the mass spectrometer in narrow m/z isolation windows (SWATH), was implemented. SWATH data file then contains all the information that would be acquired in a multitude of different experimental approaches in a single all-encompassing dataset. Analytical method performance was evaluated in terms of linearity, repeatability and matrix effect. Relative recoveries were also measured, giving values above 80% for most compounds. Matrix-matched calibration was carried out and enabled reaching the low ng mL-1 level for many mycotoxins. The observed matrix effect, in most cases suppressive, reached even values higher than 60%. The repeatability was also adequate, showing a relative standard deviation lower than 10%. All unified samples analyzed showed co-occurrence of two or more mycotoxins, recurrently zearalenone, fumonisin B1, and β-zearalenol, with an occurrence frequency ranging from 60% to 90%.

Interference of mycotoxin binders with ELISA, HPLC and LC-MS/MS analysis of aflatoxins in maize and maize gluten

The aim of this study was to investigate the impact of mycotoxin binders on the determination of aflatoxins in maize and maize gluten using various analytical methods, including ELISA, HPLC and LC-MS/MS. Three types of commercially available mycotoxin binders, yeast cell wall, mineral, and a mixture of mineral and bacterium, were investigated at inclusion levels of 0.1%, 0.2% and 0.4%. The binders were added to maize and maize gluten contaminated with aflatoxins at concentrations between 6.9 and 26.7 μg kg^-1. The samples were analysed and the values were compared with corresponding controls (samples without binders) using ANOVA. The yeast cell wall binder had no significant effect (p=0.05) on the concentration of aflatoxins measured in either maize or maize gluten at any of the three inclusion levels, regardless of which analytical method was used. The mineral binder and the mixed mineral and bacterium binder had no significant effect (p=0.05) on the measured aflatoxin concentrations in either maize or maize gluten at any of the three inclusion levels when analysis was conducted using LC-MS/MS. Inclusion of these binders resulted in significant lower (p<0.01) detection of aflatoxins in both maize and maize gluten when analysis was conducted using ELISA; the effect was dose-dependent. They also resulted in significant lower detection of aflatoxins in maize extracted by methanol/water (70/30 v/v) (p<0.0001) and in maize gluten extracted by acetonitrile/water (80/20 v/v) (p<0.05) when analysis was conducted using HPLC. However, neither the mineral binder nor the mixed mineral and bacterium binder had significant effects (p=0.05) on aflatoxin concentrations measured in maize using HPLC, when extracted by acetonitrile/water (80/20 v/v). The study demonstrated that mycotoxin binders could result in underestimation of the levels of aflatoxin contamination, depending on the nature of the binder, the extraction solvent used in the analytical method, and the composition of tested sample.

Synthesis and application of magnetic-surfaced pseudo molecularly imprinted polymers for zearalenone pretreatment in cereal samples

Zearalenone (ZEA) is a fungal contaminant widely found in grains. In cereal samples, trace zearalenone was extracted and enriched using magnetic-surfaced pseudo molecularly imprinted polymers (SPMIPs) and detected. SPMIPs were prepared with Fe₃O₄ as the magnetic core, modified halloysites nanotubes as supporting materials, and selective imprinted polymers as shells. Vinyl was modified on the surface of halloysites nanotube. SPMIPs were synthesized with pseudo templates. SPMIPs as the adsorbent of dispersed-solid phase extraction (μ-SPE) were used to purify and enrich ZEA from maize samples. After optimized, the pretreatment method was evaluated. The linearity of the method was ranged within 10-200 ng mL^-1. LOD and LOQ were 2.5 ng mL^-1 and 8 ng mL^-1 respectively. The ZEA spiking recoveries in maize samples ranged within 74.95-88.41% were with good RSDs lower than 4.25%. The developed method was successful applied in maize, oat, and wheat sample treatments and compared.

Frequency and levels of regulated and emerging mycotoxins in silage in Poland

In this study, 120 silage samples collected in 2015 from farms in Poland were analysed by a multimycotoxin method based on liquid chromatography coupled with tandem mass spectrometry. The study included toxins which are regulated within the European Union (aflatoxins, deoxynivalenol, fumonisins, T-2/HT-2 toxins, ochratoxin A and zearalenone) and non-regulated mycotoxins (enniatins, beauvericin, 8-ketotrichothecenes, sterigmatocystin, zearalenone derivatives). All silage samples were positive for at least one mycotoxin, and 61% of samples contained five or more mycotoxins simultaneously. The most frequently detected toxins were deoxynivalenol, nivalenol, zearalenone, enniatins and beauvericin, although the levels of these toxins were relatively low. The mean concentration of deoxynivalenol and zearalenon was 406 and 80.6 μg/kg, respectively, and two toxins were positive-correlated. This is the first study that provides information about emerging mycotoxins contaminating silage in Poland.

Pilot Study for The Presence of Fungal Metabolites in Sheep Milk from First Spring Milking

Introduction

A mini-study of 20 raw milk samples was conducted to examine the spectrum of fungal metabolites in sheep milk from the first spring milking.

Material and Methods

Samples were collected from randomly selected ewes in two animal flocks from the Bieszczady Mountains and analysed using liquid chromatography-tandem mass spectrometry.

Results

Out of ~700 bacterial, fungal, and plant metabolites tested for, only one mycotoxin – Enniatin B – was detected in sheep milk samples (18/20; 0.0055–0.0121 μg/kg; 0.0078 μg/kg average).

Conclusions

The results indicated that there was no high-level exposure to fungal metabolites via consumption of raw sheep milk during the sample collection period.

A novel bioassay based on aptamer-functionalized magnetic nanoparticle for the detection of zearalenone using time resolved-fluorescence NaYF4: Ce/Tb nanoparticles as signal probe

Zearalenone (ZEN) is a non-steroidal estrogenic mycotoxin produced by fungi on stored grains. The earlier detection methods used for ZEN rely on expensive equipment, time-consuming sample preparation and temperature sensitive antibodies. The current work, proposed a novel strategy based on ZEN aptamer labeled with amine-functionalized magnetic nanoparticle (MNPs) as a capture probe and time-resolved fluorescence (TRFL) nanoparticles labeled with complementary DNA (cDNA) as a signal probe. Under the optimized conditions, TRFL intensity at 544 nm was used to measure ZEN (R² = 0.9920) in the range of 0.001-10 ng mL^-1 and limits of detection (LOD) for proposed method was 0.21 pg mL^-1. The specificity of bioassay was also determined by using other mycotoxins (OTA, AFB₂, DON and Patulin) and results showed that the aptamer are specific to recognize only ZEN. The analytical applications of the present bioassay in maize and wheat samples were also examined and results were compared with existing methods. Based on these findings, it is suggested to use current rapid and simple bioassay for the determination of ZEN in food and agricultural products.

Effect of inoculants and storage temperature on the microbial, chemical and mycotoxin composition of corn silage

Objective

To evaluate the effect of lactic acid bacteria and storage temperature on the microbial, chemical and mycotoxin composition of corn silage.

Methods

Corn was harvested at 32.8% dry matter, and chopped to 1 to 2 cm. The chopped material was subjected to three treatments: i) control (distilled water); ii) 1×10⁶ colony forming units (cfu)/g of Lactobacillus plantarum; iii) 1×10⁶ cfu/g of Pediococcus pentosaceus. Treatments in triplicate were ensiled for 55 d at 20°C, 28°C, and 37°C in 1-L polythene jars following packing to a density of approximately 800 kg/m³ of fresh matter, respectively. At silo opening, microbial populations, fermentation characteristics, nutritive value and mycotoxins of corn silage were determined.

Results

L. plantarum significantly increased yeast number, water soluble carbohydrates, nitrate and deoxynivalenol content, and significantly decreased the ammonia N value in corn silage compared with the control (p<0.05). P. pentosaceus significantly increased lactic acid bacteria and yeast number and content of deoxynivalenol, nivalenol, T-2 toxin and zearalenone, while decreasing mold population and content of nitrate and 3-acetyl-deoxynivalneol in corn silage when stored at 20°C compared to the control (p<0.05). Storage temperature had a significant effect on deoxynivalenol, nivalenol, ochratoxin A, and zearalenone level in corn silage (p<0.05).

Conclusion

Lactobacillus plantarum and Pediococcus pentosaceus did not decrease the contents of mycotoxins or nitrate in corn silage stored at three temperatures.

Simultaneous analysis of multiple mycotoxins in Alpinia oxyphylla by UPLC-MS/MS

In this study, a reliable and fast method for the simultaneous quantitation of 11 mycotoxins in Alpinia oxyphylla was developed using ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLCMS/ MS). Three different extraction procedures (solid-liquid extraction, solid-phase extraction and modified QuEChERS) were evaluated. Solid-liquid extraction was fast and easy, and also provided the best recovery rate for all mycotoxins, compared to the other extraction procedures. Some crucial factors, including extraction solvent, time and temperature, were carefully optimised. Significant matrix effects were offset using matrix-matched calibration. Under these optimised conditions, our detection approach showed a good, linear dynamic range with correlation coefficients (R2) above 0.9958. The limit of quantification ranged from 0.1 to 20 μg/kg. Accuracy was determined in a selected matrix using blank samples spiked with the target mycotoxins at three different concentration levels. The recoveries ranged from 60% (T-2 toxin) to 111% (HT-2 toxin), with relative standard deviation <20%. The validated method was used to analyse 44 batches of A. oxyphylla purchased from different regions of China. Aflatoxin B1, zearalenone, ochratoxin A, fumonisin B1 and fumonisin B2 were detected in 4 mouldy samples.

Graphene oxide adsorbent based dispersive solid phase extraction coupled with multi-pretreatment clean-up for analysis of trace aflatoxins in traditional proprietary Chinese medicines

Graphene oxide (GO)-based dispersive solid phase extraction (D-SPE) method combined with multi-step preparation has been proposed for the evaluation of trace aflatoxins in proprietary Chinese medicines (PCM). After being extracted by methanol, the sample was purified based on multi-step preparation, including dehydration with MgSO₄/NaCl and cleanup with neutral alumina. Then GO was used as an adsorbent in D-SPE method for further preconcentration of aflatoxins prior to high performance liquid chromatography-fluorescence detection. The selected conditions were investigated. The Box-Behnken design (BBD) was used to optimize factors affecting adsorption procedure. Under the optimized conditions, good linear relationships had been achieved with the correlation coefficient (R²) varying from 0.9904 to 0.9990. The LODs and LOQs were ranging from 0.020 to 0.041ng/mL and 0.061 to 0.125ng/mL, respectively. The results of the recoveries were 74.0-102.7% for the four aflatoxins, while the precisions from 1.8% to 7.2% were obtained, which indicated that the method was suitable for the analysis of aflatoxins in PCM.

Fast determination of four polar contaminants in soy nutraceutical products by liquid chromatography coupled to tandem mass spectrometry

An analytical method based on a modified QuPPe (quick polar pesticide) extraction procedure coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was evaluated for the determination of four polar compounds (chlorate, fosetyl-Al, maleic hydrazide, and perchlorate) in nutraceutical products obtained from soy. Experimental conditions including extraction such as solvent, acidification, time, and clean-up sorbents were varied. Acidified acetonitrile (1 % formic acid, v/v) was used as extraction solvent instead of methanol (conventional QuPPe), which provides a doughy mixture which cannot be injected into the LC. Clean-up or derivatization steps were avoided. For analysis, several stationary phases were evaluated and Hypercarb (porous graphitic carbon) provided the best results. The optimized method was validated and recoveries ranged between 46 and 119 %, and correction factors can be used for quantification purposes bearing in mind that inter-day precision was equal to or lower than 17 %. Limits of quantification (LOQs) ranged from 4 to 100 μg kg-1. Soy-based nutraceutical products were analyzed and chlorate was detected in five samples at concentrations between 63 and 1642 μg kg-1. Graphical Abstract Analysis of polar compounds in soy-based nutraceutical products.

Core-shell poly(dopamine) magnetic nanoparticles for the extraction of estrogenic mycotoxins from milk and yogurt prior to LC-MS analysis

In this work, core-shell poly(dopamine) magnetic nanoparticles synthesized in our laboratory have been applied as dispersive solid-phase extraction (dSPE) sorbent for the extraction of a group of six mycotoxins of interest including zearalenone, α-zearalanol, β-zearalanol, α-zearalenol, β-zearalenol and zearalanone, from complex matrices such as milk (whole and skimmed cow milk and semi-skimmed goat milk) and yogurt (an unsweetened natural yogurt) prior to their LC-MS analysis. 17β-estradiol-D5 was used as internal standard. The procedure includes a deproteinization step prior to the extraction procedure. Matrix-matched calibration and a recovery study were carried out in the selected matrices, providing good linearity, relative recovery values in the range 70-120% with RSDs lower than 16% and LODs between 0.21 and 4.77μg/L for milk samples and between 0.29 and 4.54μg/kg for yogurt samples.

Mycotoxin detection

Mycotoxins are toxic metabolites of certain fungi that growth on a variety of crops, pre-harvest, during and post-harvest. Because of their toxicity, maximum admissible levels of mycotoxins are regulated worldwide and monitoring of their occurrence in several commodities is mandatory for assuring food safety and consumers' health protection. Analytical methods for mycotoxins include immunochemical-based techniques that principally apply for routinely controls and rapid, on-site detection, and chromatographic-based techniques that provide sensitive, accurate and selective determination of known mycotoxins, besides identification of new or modified compounds through tandem mass spectrometric detectors.

Analytical methods for determination of mycotoxins: An update (2009-2014)

Mycotoxins are a problematic and toxic group of small organic molecules that are produced as secondary metabolites by several fungal species that colonise crops. They lead to contamination at both the field and postharvest stages of food production with a considerable range of foodstuffs affected, from coffee and cereals, to dried fruit and spices. With wide ranging structural diversity of mycotoxins, severe toxic effects caused by these molecules and their high chemical stability the requirement for robust and effective detection methods is clear. This paper builds on our previous review and summarises the most recent advances in this field, in the years 2009-2014 inclusive. This review summarises traditional methods such as chromatographic and immunochemical techniques, as well as newer approaches such as biosensors, and optical techniques which are becoming more prevalent. A section on sampling and sample treatment has been prepared to highlight the importance of this step in the analytical methods. We close with a look at emerging technologies that will bring effective and rapid analysis out of the laboratory and into the field.

A Magnetic Nanoparticle Based Enzyme-Linked Immunosorbent Assay for Sensitive Quantification of Zearalenone in Cereal and Feed Samples

A novel enzyme-linked immunosorbent assay based on magnetic nanoparticles and biotin/streptavidin-HRP (MNP-bsELISA) was developed for rapid and sensitive detection of zearalenone (ZEN). The detection signal was enhanced and the sensitivity of the assay was improved by combined use of antibody-conjugated magnetic nanoparticles and biotin-streptavidin system. Under the optimized conditions, the regression equation for quantification of ZEN was y = −0.4287x + 0.3132 (R² = 0.9904). The working range was 0.07–2.41 ng/mL. The detection limit was 0.04 ng/mL and IC₅₀ was 0.37 ng/mL. The recovery rates of intra-assay and inter-assay ranged from 92.8%–111.9% and 91.7%–114.5%, respectively, in spiked corn samples. Coefficients of variation were less than 10% in both cases. Parallel analysis of cereal and feed samples showed good correlation between MNP-bsELISA and liquid chromatograph-tandem mass spectrometry (R² = 0.9283). We conclude that this method is suitable for rapid detection of zearalenone in cereal and feed samples in relevant laboratories.

Simultaneous Determination of Type A and B Trichothecenes and Their Main Metabolites in Food Animal Tissues by Ultraperformance Liquid Chromatography Coupled with Triple-Quadrupole Mass Spectrometry

A rapid method for the liquid chromatography-tandem mass spectrometric determination of type A and B trichothecenes and their major metabolites in chicken meat, pork, chicken liver, and swine liver was developed. The analytes included T-2 toxin, HT-2 toxin, T-2 triol, neosolaniol, deoxynivalenol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, deepoxydeoxynivalenol, and nivalenol. The compounds were extracted from samples with acetonitrile/ethyl acetate (1:3, v/v) and then cleaned up using Oasis HLB cartridges. Analysis was carried out with ultraperformance liquid chromatography-tandem mass spectrometry. The mean recoveries of spiked samples ranged from 74.1% to 96.9% with intraday and interday relative standard deviations of less than 9.9% and 9.1%, respectively. The limit of detection and limit of quantitation ranged from 3.0 to 15.0 μg/kg and from 10.0 to 50.0 μg/kg, respectively. The proposed method has been successfully applied for analysis of real samples, with the primary results indicating that, compared to mycotoxins themselves, their metabolites are more likely to occur and be detectable in animal tissue foods.

Aflatoxin M1 in processed milk and infant formulae and corresponding exposure of adult population in Serbia in 2013-2014

Aflatoxin M1 (AFM1) occurrence was analysed in 80 samples of milk and 21 samples of infant formulae on the Serbian market, using high-performance liquid chromatography with fluorescence detection. All milk samples collected in 2013 showed AFM1 contamination in the range 0.02-0.32 μg kg(-1), with a mean level of 0.13 μg kg(-1). The EU maximum level for AFM1 in milk (0.05 μg kg(-1)) was exceeded in 75% of the samples. In 2014, AFM1 was found in 83%, 70%, 80% and 58% of the samples collected in April, July, September and December, respectively, exceeding the limit in 5% of the samples taken in July. The additional number of liver cancer cases per year associated with exposure to AFM1 was estimated to be 0.004 in the adult population. Regarding infant formulae, AFM1 was found in only one sample.