Scientific Opinion on the risks for animal and public health related to the presence of phomopsins in feed and food

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.

Quinolizidine alkaloids and phomopsin A in animal feed containing lupins: co-occurrence and carry-over into veal products

Lupins are used in animal feed because of their excellent nutritional composition. Australian and European Lupinus angustifolius seeds are incorporated in compound feed of calves for veal production in Belgium. To investigate the co-occurrence of quinolizidine alkaloids (QAs) and phomopsin A (PHO A) in lupin seeds and lupin-containing feed, and the potential transfer to animal-derived foods, representative samples were obtained from various actors in the chain. A UHPLC-MS/MS method was validated for the simultaneous quantification of seven QAs and PHO A in relevant matrices. Results indicate highly consistent total QA (TQA) levels in Australian lupins (173 ± 24 mg/kg) (n = 25), while European samples showed a high variability (1442 ± 1497 mg/kg) (n = 15). PHO A was detected in 7 of 40 samples. Lupin-containing feed had a mean TQA content of 42 ± 28 mg/kg (n = 20). An in vivo feeding trial demonstrated the transfer of QAs to muscle and liver of calves that were fed the lupin-containing feed. Highest concentrations were found for lupanine in liver tissue samples (67 ± 46 µg/kg). PHO A concentrations were below the LOD in all feed and tissue samples. These results indicate that animal-derived foods (veal meat/liver) are a potential route for QAs to enter the food chain.

Multiple mycotoxins in commonly used edible oils: Occurrence and evaluation of potential health risks

In this study, the contamination of 51 mycotoxins in 416 edible oils were determined by UPLC-MS/MS. Totally, twenty-four mycotoxins were detected and nearly half of the samples (46.9%, n = 195) were contaminated simultaneously with six to nine kinds of mycotoxins. The predominant mycotoxins and contamination characteristics varied depending on the type of oils. More specifically, four enniatins, alternariol monomethyl ether (AME) and zearalenone were the most frequent combination. Overall, peanut and sesame oils (10.7-11.7 mycotoxins on average) were found to be the most contaminated matrices whereas camellia and sunflower seed oils (1.8-2.7 species) were the opposite. Dietary exposure risks of mycotoxins were acceptable in most cases, however, the ingestion of aflatoxins (especially aflatoxin B₁) through peanut and sesame oil (margin of exposure: 239.4-386.3 < 10000) exceeded the acceptable carcinogenic risk level. Meanwhile, the risks of cumulative ingestion through the food chain should be of great concern, especially sterigmatocystin, ochratoxin A, AME and zearalenone.

[Determination of seven Alternaria toxins in infant milk powder by solid phase extraction coupled with ultra-performance liquid chromatography-tandem mass spectrometry]

Alternaria toxin is a general term for a class of toxic metabolites produced by Alternaria, which widely exists in soil, grain, vegetables, and fruits. This mycotoxin is extremely harmful to human health. It is well known that infant milk powder containing vegetable oil is easily contaminated by Alternaria alternata. Alternaria toxins have thus become an increasingly important focus in food. Rapid and accurate detection of Alternaria toxin residues in food is of great significance for food safety. This requires pretreatment to purify the target toxins and maximize the accuracy and precision of the analysis. In this study, a rapid method based on online solid phase extraction/purification and ultra-performance liquid chromatography-tandem mass spectrometry (online SPE UPLC MS/MS) was established to detect seven Alternaria toxins (alternariol monomethyl ether, altenuene, tenuazonic acid, alternariol, tentoxin, altenusin, and altertoxin Ⅰ) in infant milk powder. First, the mass spectrometry and chromatographic conditions were optimized. A BEH-C18 column (50 mm×2.1 mm, 1.7 μm) was selected, with 0.1% formic acid aqueous solution-acetonitrile as the mobile phase. Then, the extraction conditions (extraction agent ratio and extraction method) and the solid phase extraction process (extraction column, type and volume of the eluent, and pH of the sample loading solution) were optimized. One gram of milk powder (accurate to 0.01 g) was weighed into a 50 mL tip and bottom plug centrifuge tube. Acetonitrile-water (84∶16, v/v) was set as the extraction agent for the first two cycles, and acetonitrile-methanol-water (45∶10∶45, v/v/v) was set as the third extraction agent. Horizontal shaking for 30 min was the best extraction method. The sample was centrifuged at 9500 r/min for 10 min, and the supernatant extracted many times was mixed and blown with nitrogen at 40 ℃. The sample was redissolved in first-order water (pH 5.5), purified on an HLB column, and successively activated with 6 mL methanol and 6 mL first-order water (pH 5.5). The solution was then loaded onto the column, and the SPE was adjusted to ensure that the water sample flowed through the column at the rate of 1 mL/min so that the column did not dry up during the analysis process before the end of sample loading. The column was rinsed with 12 mL of first-order water. After leaching, the negative pressure filtration was continued for approximately 5 min, followed by elution with 10 mL methanol, and the eluted solution was directly tested after passing through a 0.22 μm filter membrane, without concentration. The analytes were determined by electrospray ionization (ESI) with alternating positive and negative ions. Under the optimal analysis conditions, the linear relationships of the seven Alternaria toxins were good in the mass concentration range of 0.5-200 μg/L, with coefficients of determination (R2)>0.9903. The limits of detection and limits of quantification were 0.15-0.64 μg/kg and 0.54-2.24 μg/kg, respectively. The recoveries of the seven Alternaria toxins were 79.1%-114.3%, and the relative standard deviations were less than 8.87% at different concentrations. The method was applied to the determination and analysis of 60 samples of infant milk powder, and the results showed that no toxin was found in stage one or stage two of the milk powder. Only one sample of the stage three of milk powder was detected, which was tentoxin, and the content was 4.97 μg/kg. The developed method is accurate, rapid, simple, sensitive, repeatable, and stable. It can be used for the practical determination of seven Alternaria toxins in infant milk powder.

Growth and toxin production of phomopsin A and ochratoxin A forming fungi under different storage conditions in a pea (Pisum sativum) model system

Phomopsins are mycotoxins mainly infesting lupines, with phomopsin A (PHOA) being the main mycotoxin. PHOA is produced by Diaporthe toxica, formerly assigned as toxigenic Phomopsis leptostromiformis, causing infections in lupine plants and harvested seeds. However, Diaporthe species may also grow on other grain legumes, similar to Aspergillus westerdijkiae as an especially potent ochratoxin A (OTA) producer. Formation of PHOA and OTA was investigated on whole field peas as model system to assess fungal growth and toxin production at adverse storage conditions. Field pea samples were inoculated with the two fungal strains at two water activity (aw) values of 0.94 and 0.98 and three different levels of 30, 50, and 80% relative air humidity.After 14 days at an aw value of 0.98, the fungi produced 4.49 to 34.3 mg/kg PHOA and 1.44 to 3.35 g/kg OTA, respectively. Strains of D. toxica also tested showed higher PHOA concentrations of 28.3 to 32.4 mg/kg.D. toxica strains did not grow or produce PHOA at an aw values of 0.94, while A. westerdijkiae still showed growth and OTA production.Elevated water activity has a major impact both on OTA and, even more pronouncedly, on PHOA formation and thus, proper drying and storage of lupins as well as other grain legumes is crucial for product safety.

Single and combined effects of regulated and emerging mycotoxins on viability and mitochondrial function of SH-SY5Y cells

Co-occurrence of emerging and regulated mycotoxins in contaminated samples has been widely documented, but studies about their combined toxicity are scarce. In this report, the regulated mycotoxins deoxynivalenol, fumonisin B1 and zearalenone, and the emerging ones enniatin A, enniatin B and beauvericin were tested in SH-SY5Y human neuroblastoma cells. Their individual and binary combined effects on cell viability and mitochondrial function were evaluated. The results with individual mycotoxins revealed that deoxynivalenol and emerging mycotoxins were the most damaging to neuronal cells, presenting IC₅₀ values between 0.35 and 2.4 μM. Interestingly, non-regulated mycotoxins triggered apoptosis by affecting to mitochondrial membrane potential. However, when regulated and non-regulated mycotoxins were binary mixed, antagonistic effects were found in all cases. Finally, cow feed and milk extracts were analysed by UHPLC-MS/MS, detecting the presence of several mycotoxins included in this study. These extracts were tested in neuroblastoma cells, and damaging effects on cell viability were found. Although binary combinations of mycotoxins produced antagonistic effects, their mixture in natural matrixes induces greater effects than expected. Therefore, it would be interesting to explore the matrix influence on mycotoxin toxicity, and to continue studying the neurotoxic mechanism of action of emerging mycotoxins, as they could be a health hazard.

A Dilute and Shoot Strategy for Determining Alternaria Toxins in Tomato-Based Samples and in Different Flours Using LC-IDMS Separation

Alternaria toxins are emerging mycotoxins whose regulation and standardization are in progress by the European Commission and the European Committee for Standardization. This paper describes a dilute and shoot approach to determine five Alternaria toxins in selected food samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The strategy involves sample extraction with acidified aqueous methanol, followed by a solvent change accomplished via sample evaporation and reconstitution. The quantification is based on isotope dilution, applying all corresponding isotopically labeled internal standards to compensate possible matrix effects of the analysis. The main advantages of the present method over other existing methods includes simple and effective sample preparation, as well as detection with high sensitivity. The five-fold sample dilution can decrease matrix effects, which were evaluated with both external and internal standard methods. The results demonstrated a limit of quantification lower than 1.0 µg/kg for all five analytes for the first time. The newly presented method showed acceptable accuracy (52.7-111%) when analyzing naturally contaminated and spiked standard samples at the described levels. The method was validated for tomato-based and flour samples (wheat, rye, and maize). The absolute recovery ranged from 66.7% to 91.6% (RSD < 10%). The developed method could be an alternative approach for those laboratories that exclude sample cleanup and pre-concentration of state-of-the-art instruments with enhanced sensitivity.

Impact of Mycotoxins on Animals' Oxidative Status

Mycotoxins appear to be the "Achilles' heel" of the agriculture sector inducing enormous economic losses and representing a severe risk to the health of humans and animals. Although novel determination protocols have been developed and legislation has been implemented within Europe, the side effects of mycotoxins on the homeostatic mechanisms of the animals have not been extensively considered. Feed mycotoxin contamination and the effects on the antioxidant status of livestock (poultry, swine, and ruminants) are presented. The findings support the idea that the antioxidant systems in both monogastrics and ruminants are challenged under the detrimental effect of mycotoxins by increasing the toxic lipid peroxidation by-product malondialdehyde (MDA) and inhibiting the activity of antioxidant defense mechanisms. The degree of oxidative stress is related to the duration of contamination, co-contamination, the synergetic effects, toxin levels, animal age, species, and productive stage. Since the damaging effects of MDA and other by-products derived by lipid peroxidation as well as reactive oxygen species have been extensively studied on human health, a more integrated monitoring mechanism (which will take into account the oxidative stability) is urgently required to be implemented in animal products.

Scientific opinion on the risks for animal and human health related to the presence of quinolizidine alkaloids in feed and food, in particular in lupins and lupin-derived products

The European Commission asked EFSA for a scientific opinion on the risks for animal and human health related to the presence of quinolizidine alkaloids (QAs) in feed and food. This risk assessment is limited to QAs occurring in Lupinus species/varieties relevant for animal and human consumption in Europe (i.e. Lupinus albus L., Lupinus angustifolius L., Lupinus luteus L. and Lupinus mutabilis Sweet). Information on the toxicity of QAs in animals and humans is limited. Following acute exposure to sparteine (reference compound), anticholinergic effects and changes in cardiac electric conductivity are considered to be critical for human hazard characterisation. The CONTAM Panel used a margin of exposure (MOE) approach identifying a lowest single oral effective dose of 0.16 mg sparteine/kg body weight as reference point to characterise the risk following acute exposure. No reference point could be identified to characterise the risk of chronic exposure. Because of similar modes of action for QAs, the CONTAM Panel used a group approach assuming dose additivity. For food, the highest mean concentration of Total QAs (TotQAs) (i.e. the 6 most abundant QAs) was found in lupin seed samples classified as 'Lupins (dry) and similar-'. Due to the limited data on occurrence and consumption, dietary exposure was calculated for some specific scenarios and no full human health risk characterisation was possible. The calculated margin of exposures (MOEs) may indicate a risk for some consumers. For example, when lupin seeds are consumed without a debittering step, or as debittered lupin seeds high in QA content and when 'lupin-based meat imitates' are consumed. For horses, companion and farm animals, other than salmonids, the available database on adverse effects was too limited to identify no-observed-adverse-effect levels and/or lowest-observed-adverse-effect levels and no risk characterisation was possible. For salmonids, the CONTAM Panel considers the risk for adverse effects to be low.

Overview of the activities of the European Food Safety Authority on mycotoxins in food and feed

Mycotoxins are widely occurring in foods and feeds and dietary exposure to them can induce various types of adverse health effects in humans and animals. Since its establishment in 2002, the European Food Safety Authority (EFSA) has assessed risks of dietary exposure to mycotoxins for public health and for the health of farm and companion animals on the request of the European Commission and has assessed safety and efficacy of feed additives for the reduction of contamination of feed by mycotoxins within the European Union authorisation process for feed additives. Over 40 scientific opinions on risks of mycotoxins for human and animal health and other reports on mycotoxins have been issued by the authority for the use of the European risk managers. Mycotoxins belong to one of the important areas of the EFSA work. Occurrence data on mycotoxins submitted to EFSA by the European national food safety bodies and research institutions have been collected in the EFSA databases and have informed its scientific opinions and reports on mycotoxins. Similarly, many EFSA-funded projects conducted by the European research organisations, not only to generate data on occurrence, but also data on toxicity of mycotoxins, have provided valuable information for the risk assessments of EFSA. Aflatoxin and deoxynivalenol are the mycotoxins, for which EFSA has delivered most of its scientific mycotoxin opinions. Very recently also modified forms of mycotoxins have been included in the EFSA risk assessments. In this review paper an overview of many different EFSA activities on mycotoxins is given. It also includes a brief description how EFSA develops its scientific opinions and works.

Detection of a Toxic Methylated Derivative of Phomopsin A Produced by the Legume-Infesting Fungus Diaporthe toxica

Phomopsin A (PHO-A), produced by the fungus Diaporthe toxica, is a mycotoxin known to be responsible for fatal liver disease of lupin-fed sheep. The full spectrum of the toxic secondary metabolites produced by D. toxica is still unknown. PHO-A and the naturally occurring derivatives B-E have been subject to several studies to reveal their structures as well as chemical and toxicological properties. In this work, a methylated derivative (1) of PHO-A isolated from lupin seeds inoculated with D. toxica is described. It was characterized by high-resolution mass and NMR data and shown to be the N-methylated derivative of PHO-A. 1 is cytotoxic against HepG2 cells.

A review of the efficacy of mycotoxin detoxifying agents used in feed in light of changing global environment and legislation

In the recent years, mycotoxins have undoubtedly gained a keen interest of the scientific community studying food safety. The main reason is their profound impact on both human and animal health. International surveys reveal a low percentage of feed samples being contaminated above permitted/guideline levels, developed to protect consumers of animal derived products. However, the deleterious impact of feed co-contaminated at low levels with numerous both known and regulated as well as novel mycotoxins on producing animals has been described. Associated effects on agro-economics world-wide include substantial pecuniary losses which are borne by the society as a whole. Even though good agronomic practice is thought to be the most effective way of preventing animal feed contamination, the EC have recognised the need to introduce an additional means of management of feed already contaminated with low-levels of mycotoxins to alleviate detrimental effects on agricultural production efficiency. This review discusses types of feed detoxifying agents described in scientific literature, their reported efficacy in both in vitro and in vivo systems, and comparison with available commercial formulations in the light of increasing knowledge regarding mycotoxin prevalence in the changing global environment.

Biosynthesis and characterization of ¹⁵N₆-labeled phomopsin A, a lupin associated mycotoxin produced by Diaporthe toxica

The hepatotoxin phomopsin A (PHO-A), a secondary metabolite mainly produced by the fungus Diaporthe toxica, occurs predominantly on sweet lupins. Along with the growing interest in sweet lupins for food and feed commodities, concerns have been raised about fungal infestations, and consequently, about the determination of PHO-A. High performance liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) represents the most suitable analytical technique for sensitive and selective detection of mycotoxins including PHO-A. However, isotopic labeled substances are needed as internal standards for a reliable and convenient quantification. As no isotope standard for PHO-A is currently available, a biosynthesis of fully (15)N6-labeled PHO-A was established by cultivation of D. toxica on defined media containing Na(15)NO3 and (15)N-labeled yeast extract as the only nitrogen sources. The identity of (15)N6-PHO-A was confirmed by high resolution mass spectrometry. The new (15)N6-labeled standard will facilitate the method development for PHO-A including a more accurate quantification by LC-MS/MS.

Development and validation of an LC-MS/MS method for the detection of phomopsin A in lupin and lupin-containing retail food samples from the Netherlands

Phomopsins (PHO) are mycotoxins produced by the fungus Diaporthe toxica (also referred to as Phomopsis leptostromiformis). Lupin is the most important host crop for this fungus and PHO are suspected as cause of lupinosis, a deadly liver disease, in sheep. Lupin is currently in use to replace genetically modified soy in many food products available on the European market. However, a validated method for analysis of PHO is not available until now. In this work, a dilute-and-shoot LC-MS/MS-based method was developed for the quantitative determination and identification of phomopsin A (PHO-A) in lupin and lupin-containing food. The method involved extraction by a mixture of acetonitrile/water/acetic acid (80/20/1 v/v), dilution of the sample in water, and direct injection of the crude extract after centrifugation. The method was validated at 5 and 25 µg PHO-A kg(-1) product. The average recovery and RSD obtained were 79% and 9%, respectively. The LOQ (the lowest level for which adequate recovery and RSD were demonstrated) was 5 µg PHO-A kg(-1). Identification of PHO-A was based on retention time and two transitions (789 > 226 and 789 > 323). Using the average of solvent standards from the sequence as a reference, retention times were all within ± 0.03 min and ion ratios were within ± 12%, which is compliant with European Union requirements. The LOD (S/N = 3 for the least sensitive transition) was 1 µg PHO-A kg(-1) product. Forty-two samples of lupin and lupin-containing food products were collected in 2011-2012 from grocery stores and internet shops in the Netherlands and analysed. In none of the samples was PHO-A detected.