Natural occurrence, analysis, and prevention of mycotoxins in fruits and their processed products

Simultaneous detection of five mycotoxins in traditional Chinese medicines (TCMs) by visual protein microarray

The pollution of mycotoxins to crops such as traditional Chinese medicines (TCMs) is an established problem throughout the world. Thus, mycotoxin determination in TCMs during production and processing is significantly necessary, which means rapid, sensitive and accurate analytical methods are needed. In this work, a new method of visual protein microarray based on a 96-well microtiter plate was proposed. Combined with a colorimetric method, five mycotoxins (ochratoxin A, zearalenone, deoxynivalenol, aflatoxin B1 and fumonisin B1) in 90 samples (TCMs) could be detected simultaneously within 30 minutes. The detection limits for the five mycotoxins are 0.25 μg/kg, 0.33 μg/kg, 11.84 μg/kg, 0.06 μg/kg, and 3.58 μg/kg, which can satisfy specified requirements of mycotoxins in the Chinese Pharmacopoeia (2020 edition) adequately. Under repeated conditions, experiments were carried out on actual samples to verify the feasibility of the method. The results showed that the recoveries of all analytes were between 70 % and 120 %, and the relative standard deviations were less than 15 %. In comparison to LC-MS/MS, this method significantly reduces the required time, and the colorimetric technique offers more direct results compared to fluorescence-based screening assays. This method exhibits substantial potential for the rapid and sensitive on-site detection of TCMs for quality control.

Spirobenzofuran Mitigates Ochratoxin A-Mediated Intestinal Adverse Effects in Pigs through Regulation of Beta Defensin 1

Antimicrobial peptides (AMPs) function to extensively suppress various problematic factors and are considered a new alternative for improving livestock health and enhancing immunomodulation. In this study, we explored whether AMP regulation has positive influences on Ochratoxin A (OTA) exposure using a porcine intestinal epithelial cell line (IPEC-J2 cells). We constructed a beta-defensin 1 (DEFB1) expression vector and used it to transfection IPEC-J2 cells to construct AMP overexpression cell lines. The results showed that OTA induced cytotoxicity, decreased cell migration, and increased inflammatory markers mRNA in IPEC-J2 cells. In DEFB1 overexpressing cell lines, OTA-induced reduced cell migration and increased inflammatory markers mRNA were alleviated. Additionally, a natural product capable of inducing DEFB1 expression, which was selected through high-throughput screening, showed significant alleviation of cytotoxicity, cell migration, and inflammatory markers compared to OTA-treated IPEC-J2 cells. Our finding provides novel insights and clues for the porcine industry, which is affected by OTA exposure.

The occurrence and management of fumonisin contamination across the food production and supply chains

BACKGROUND

Fumonisins (FUMs) are among the most common mycotoxins in plant-derived food products. FUMs contamination has considerably impacted human and animal health, while causing significant economic losses. Hence, management of FUMs contamination in food production and supply chains is needed. The toxicities of FUMs have been widely investigated. FUMs management has been reported and several available strategies have been developed successfully to mitigate FUMs contamination present in foods. However, currently available management of FUMs contamination from different phases of food chains and the mechanisms of some major strategies are not comprehensively summarized.

AIM OF REVIEW

This review comprehensively characterize the occurrence, impacts, and management of FUMs contamination across food production and supply chains. Pre- and post-harvest strategies to prevent FUMs contamination also are reviewed, with an emphasis on the potential applications and the mechanisms of major mitigation strategies. The presence of modified FUMs products and their potential toxic effects are also considered. Importantly, the potential application of biotechnological approaches and emerging technologies are enunciated.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Currently available pre- and post-harvest management of FUMs contamination primarily involves prevention and decontamination. Prevention strategies are mainly based on limiting fungal growth and FUMs biosynthesis. Decontamination strategies are implemented through alkalization, hydrolysis, thermal or chemical transformation, and enzymatic or chemical degradation of FUMs. Concerns have been raised about toxicities of modified FUMs derivatives, which presents challenges for reducing FUMs contamination in foods with conventional methodologies. Integrated prevention and decontamination protocols are recommended to control FUMs contamination across entire value chains in developed countries. In developing countries, several other approaches, including cultivating, introducing Bt maize, simple sorting/cleaning, and dehulling, are suggested. Future studies should focus on biotechnological approaches, emerging technologies, and metagenomic/genomic identification of new degradation enzymes that could allow better opportunities to manage FUMs contamination in the entire food system.

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.

Nutritional Values and Bio-Functional Properties of Fungal Proteins: Applications in Foods as a Sustainable Source

From the preparation of bread, cheese, beer, and condiments to vegetarian meat products, fungi play a leading role in the food fermentation industry. With the shortage of global protein resources and the decrease in cultivated land, fungal protein has received much attention for its sustainability. Fungi are high in protein, rich in amino acids, low in fat, and almost cholesterol-free. These properties mean they could be used as a promising supplement for animal and plant proteins. The selection of strains and the fermentation process dominate the flavor and quality of fungal-protein-based products. In terms of function, fungal proteins exhibit better digestive properties, can regulate blood lipid and cholesterol levels, improve immunity, and promote gut health. However, consumer acceptance of fungal proteins is low due to their flavor and safety. Thus, this review puts forward prospects in terms of these issues.

The use of surfactin in inhibiting Botrytis cinerea and in protecting winter jujube from the gray mold

Surfactin has the potential to be used as a food preservative. However, efficiency and action mechanism in various applications need more assessments and research. In this study, the antifungal effects and the mechanism of action of surfactin on the fungus Botrytis cinerea were investigated. The effects of applying surfactin for the removal of gray mold on the quality of winter jujube were investigated based on the changes in fruit fatty acids. The results showed that (1) surfactin significantly inhibited the growth of B. cinerea, the EC₅₀ at 5 d was 46.42 mg/L. (2) Surfactin significantly reduced the disease incidence and diameter of gray mold-inoculated winter jujube in a concentration-dependent manner. For that treated with surfactin at the EC_50, the incidence decreased by 38.89%. (3) For B. cinerea under surfactin treatment, the mycelial morphology changed, the levels of total lipids and ergosterol decreased, the reactive oxygen species levels increased, and the cell integrity was completely damaged. (4) For winter jujube inoculated by B. cinerea, the contents of saturated fatty acids decreased and unsaturated fatty acids increased. For those under the surfactin treatments, winter jujube maintained the fatty acid composition at the level of non-inoculated groups. Mechanical injury significantly changed the fatty acid composition of winter jujube; however, surfactin not only was able to inhibit the growth of gray mold but also mitigated the adverse effects from mechanical injury. The present study demonstrated the potential applications of surfactin in the preservation of postharvest fruit quality.

Comprehensive review on patulin and Alternaria toxins in fruit and derived products

Mycotoxins are toxic secondary metabolites produced by certain fungi, which can contaminate various food commodities, including fruits and their derived products. Patulin and Alternaria toxins are among the most commonly encountered mycotoxins in fruit and their derived products. In this review, the sources, toxicity, and regulations related to these mycotoxins, as well as their detection and mitigation strategies are widely discussed. Patulin is a mycotoxin produced mainly by the fungal genera Penicillium, Aspergillus, and Byssochlamys. Alternaria toxins, produced by fungi in the Alternaria genus, are another common group of mycotoxins found in fruits and fruit products. The most prevalent Alternaria toxins are alternariol (AOH) and alternariol monomethyl ether (AME). These mycotoxins are of concern due to their potential negative effects on human health. Ingesting fruits contaminated with these mycotoxins can cause acute and chronic health problems. Detection of patulin and Alternaria toxins in fruit and their derived products can be challenging due to their low concentrations and the complexity of the food matrices. Common analytical methods, good agricultural practices, and contamination monitoring of these mycotoxins are important for safe consumption of fruits and derived products. And Future research will continue to explore new methods for detecting and managing these mycotoxins, with the ultimate goal of ensuring the safety and quality of fruits and derived product supply.

The mediating role of coagulation function on the association of prenatal exposure to aflatoxin B1 and postpartum hemorrhage in Guangxi, China

Pregnant women are vulnerable to certain environmental agents, one of which is aflatoxin. As one of the most popular aflatoxins, Aflatoxin B1 (AFB1) has recently garnered increased attention concerning its potential association between exposure and adverse pregnancy outcomes. The aims of the study were to examine the associations between prenatal exposure to AFB1 and postpartum hemorrhage (PPH), and whether coagulation function has a mediating effect on their relationship. A total of 379 mother-infant pairs were included in the present study. Prenatal serum AFB1 albumin (AFB1-Alb) adduct levels in peripheral venous blood were detected by using an ELISA kit. Multiple linear and logistics regression models were applied to analyze the relationship between AFB1-Alb levels and PPH. We found mothers with high levels of AFB1-Alb adduct levels had significantly increased postpartum blood loss (partial regression coefficient (β) = 50.71, 95% confidence interval (CI) 3.48, 97.95). Mothers with high levels of AFB1-Alb adduct levels also had significantly increased risk of PPH (odds ratio (OR) = 4.81, 95% CI 1.01, 22.98). Moreover, concentrations of AFB1-Alb were positively associated with activated partial thromboplastin time (APTT) while negatively associated with fibrinogen (FIB). One-unit increase in APTT was correlated with a 6.62-ml (95% CI 3.04, 10.20) increase in postpartum blood loss. Mediation analysis suggested that the maternal blood APTT levels had a positive mediating effect in the association between AFB1-Alb adduct levels and postpartum blood loss (β = 0.32, 95% CI 0.04, 0.68). These results indicated that prenatal exposure to AFB1 was associated with increased postpartum blood loss, possibly by interfering with maternal APTT levels.

Contamination, Detection and Control of Mycotoxins in Fruits and Vegetables

Mycotoxins are secondary metabolites produced by pathogenic fungi that colonize fruits and vegetables either during harvesting or during storage. Mycotoxin contamination in fruits and vegetables has been a major problem worldwide, which poses a serious threat to human and animal health through the food chain. This review systematically describes the major mycotoxigenic fungi and the produced mycotoxins in fruits and vegetables, analyzes recent mycotoxin detection technologies including chromatography coupled with detector (i.e., mass, ultraviolet, fluorescence, etc.) technology, electrochemical biosensors technology and immunological techniques, as well as summarizes the degradation and detoxification technologies of mycotoxins in fruits and vegetables, including physical, chemical and biological methods. The future prospect is also proposed to provide an overview and suggestions for future mycotoxin research directions.

Presence of Aflatoxin M1 in Commercial Milk in Paraguay

ABSTRACT

The presence of aflatoxin M1 (AFM1) in milk is a public health concern because milk is a significant part of human diets worldwide. In economies where AFM1 monitoring is low or nonexistent, the possibility of AFM1 contamination might be increased. Our study was conducted to detect and quantify AFM1 in fluid milk and milk drinks of various brands, fat concentrations, packages, and heat treatments sold in the Metropolitan Area of Asunción, Paraguay. Eighty samples were collected from supermarkets in the Metropolitan Area of Asunción following a nonprobability sampling method. An enzyme-linked immunosorbent assay for AFM1 (25 to 500 ppt) was used to quantify the toxin, and results were analyzed with nonparametric methods. All samples were positive values for AFM1 (above the detection limit of 25 ng/kg); 85% of the samples had 30 to 50 ng/kg, and 15% had >500 ng/kg. No significant difference in AFM1 concentration was found based on fat concentration, heat treatment, or type of packaging of these milk products; however, significant differences were found between brands.

HIGHLIGHTS

Antifungal Activity of Biocontrol Agents In Vitro and Potential Application to Reduce Mycotoxins (Aflatoxin B1 and Ochratoxin A)

Food bio-preservatives are requested as substituents of chemical pesticides in food. The aim of this study was to carry out a screening of twenty biocontrol agents (BCAs) for their potential fungicidal activity in vitro. Twenty BCAs were tested against ten pathogenic fungi. Some of the cell-free supernatants (CFS) tested showed in vitro antifungal activity versus pathogenic fungi. The highest fungicidal activity was observed in the fermented CFS of Paenibacillus chibensis CECT 375, Bacillus amyloliquefaciens CECT 493, and Pantoea agglomerans CECT 850, which showed a minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values of 125 and 250 g/L, respectively. The compounds responsible for the antifungal activity, such as organic and phenolic acids, were determined. Lactic acid, acetic acid, benzoic acid, and phenyllactic acid among others can be related to antifungal activity. HPLC-MS/MS analysis showed a reduction of ochratoxin A (OTA) and aflatoxin B1 (AFB1) up to 26% (Paenibacillus alvei CECT 2) and 55% (Paenibacillus polymyxa CECT 155), respectively. The present study prompts that metabolism products of BCAs are propitious for the bioconservation of food, due to their ability to reduce the proliferation of mycotoxigenic fungi and mycotoxins production.

The Existing Methods and Novel Approaches in Mycotoxins' Detection

Mycotoxins represent a wide range of secondary, naturally occurring and practically unavoidable fungal metabolites. They contaminate various agricultural commodities like cereals, maize, peanuts, fruits, and feed at any stage in pre- or post-harvest conditions. Consumption of mycotoxin-contaminated food and feed can cause acute or chronic toxicity in human and animals. The risk that is posed to public health have prompted the need to develop methods of analysis and detection of mycotoxins in food products. Mycotoxins wide range of structural diversity, high chemical stability, and low concentrations in tested samples require robust, effective, and comprehensible detection methods. This review summarizes current methods, such as chromatographic and immunochemical techniques, as well as novel, alternative approaches like biosensors, electronic noses, or molecularly imprinted polymers that have been successfully applied in detection and identification of various mycotoxins in food commodities. In order to highlight the significance of sampling and sample treatment in the analytical process, these steps have been comprehensively described.

Mycotoxins Affecting Animals, Foods, Humans, and Plants: Types, Occurrence, Toxicities, Action Mechanisms, Prevention, and Detoxification Strategies-A Revisit

Mycotoxins are produced by fungi and are known to be toxic to humans and animals. Common mycotoxins include aflatoxins, ochratoxins, zearalenone, patulin, sterigmatocystin, citrinin, ergot alkaloids, deoxynivalenol, fumonisins, trichothecenes, Alternaria toxins, tremorgenic mycotoxins, fusarins, 3-nitropropionic acid, cyclochlorotine, sporidesmin, etc. These mycotoxins can pose several health risks to both animals and humans, including death. As several mycotoxins simultaneously occur in nature, especially in foods and feeds, the detoxification and/or total removal of mycotoxins remains challenging. Moreover, given that the volume of scientific literature regarding mycotoxins is steadily on the rise, there is need for continuous synthesis of the body of knowledge. To supplement existing information, knowledge of mycotoxins affecting animals, foods, humans, and plants, with more focus on types, toxicity, and prevention measures, including strategies employed in detoxification and removal, were revisited in this work. Our synthesis revealed that mycotoxin decontamination, control, and detoxification strategies cut across pre-and post-harvest preventive measures. In particular, pre-harvest measures can include good agricultural practices, fertilization/irrigation, crop rotation, using resistant varieties of crops, avoiding insect damage, early harvesting, maintaining adequate humidity, and removing debris from the preceding harvests. On the other hand, post-harvest measures can include processing, chemical, biological, and physical measures. Additionally, chemical-based methods and other emerging strategies for mycotoxin detoxification can involve the usage of chitosan, ozone, nanoparticles, and plant extracts.

Occurrence of Alternariol and Alternariolmonomethyl ether in edible oils: Their thermal stability and intake assessment in state of Uttar Pradesh, India

Alternariol (AOH) and Alternariol monomethyl ether (AME) mycotoxins are found to be present naturally in various food commodities, such as barley, oats, pepper, rye, sorghum, sunflower seeds, tomatoes, and wheat. A few epidemiological studies have correlated the consumption of Alternaria-contaminated cereal grains with higher occurrence of esophageal cancer in Chinese populations. In addition, several studies have reported the toxicological properties of Alternaria mycotoxins. However, surveillance data on AOH and AME occurrence are still limited. Therefore, the goal of this study was to determine the presence of AOH and AME in various commonly consumed, edible oils using HPLC-FLD method. Thirty four percent of samples were found positive for AOH and 35% for AME. Moreover, AOH retained 80% stability, while AME retained 84% stability, after deep frying for 25 min, which is an important factor with respect to Indian cooking style. To the best of our knowledge, this is the first report on the presence of Alternaria mycotoxins in edible oils and their probable dietary intake in Indian population. This surveillance study may help in formulating guidelines for Alternaria mycotoxin levels in India, which are not yet implemented by Food Safety and Standards Authority of India. PRACTICAL APPLICATIONS: At present, no safety guidelines exist for Alternaria mycotoxins in any part of the world. This study will help the regulatory bodies to set permissible levels of Alternaria mycotoxins to safeguard the health of consumers. This study shows that Alternaria mycotoxins are heat stable even after deep frying for 25 min. The data will also help to issue guidelines against exposure of these mycotoxins, keeping in the mind the heat stability factor.

Removal of aflatoxin b1 and t-2 toxin by bacteria isolated from commercially available probiotic dairy foods

This study isolated lactic acid bacteria from commercially available probiotic foods to determine their capacity to remove aflatoxin B₁ (AFB₁) and trichothecene-2 (T-2). The removal rates by original live and heat-treated cells of lactic acid bacteria (LAB) were compared to test the effect of heat treatment on efficacy. LAB is capable to remove up to 46% of AFB₁ and up to 45% of T-2 toixn. The toxin removal capability increased as toxin concentration increased despite bacterial cell viability declining. Surprisingly, the denatured LAB removed greater percentages of AFB₁ (up to 62%) and T-2 (up to 52%) than live bacterial cells (P < 0.05), lending support to the hypothesis that there is higher binding of toxins to the cell membrane of nonviable cells. The research provided practical evidences, which suggest that when ingested into the gut biota, LAB could likely reduce absorption of AFB₁ and T-2 from contaminated foods.

Investigating the Efficiency of Hydroxycinnamic Acids to Inhibit the Production of Enniatins by Fusarium avenaceum and Modulate the Expression of Enniatins Biosynthetic Genes

Enniatins (ENNs) that belong to the group of emerging mycotoxins are widespread contaminants of agricultural commodities. There is currently insufficient evidence to rule out health concerns associated with long-term exposure to ENNs and efforts must be strengthened to define a control strategy. While the potential of plant compounds to counteract the contamination with legislated mycotoxins has been reported, little remains known regarding ENNs. The present study evidenced for the first time the efficiency of hydroxycinnamic acids to inhibit the fungal growth and ENNs yield by Fusarium avenaceum. Notably, 0.5 mM of exogenous ferulic, caffeic, and p-coumaric acids led to a drastic reduction of ENNs synthesis in pH4 broths, with ferulic acid being the most potent. The ENNs production inhibitory activity of ferulic acid was shown to be associated with a significant down-regulation of the expression of ENNs biosynthetic genes. To further investigate the bioactivity of ferulic acid, its metabolic fate was characterized in fungal broths and the capacity of F. avenaceum to metabolize it through a C2-cleavage type degradation was demonstrated. Overall, our data support the promising use of ferulic acid in ENNs control strategies, either as part of an environmentally friendly plant-care product or as a biomarker of plant resistance.

Mycotoxins in Functional Beverages: A Review

Consumer dietary habits have drastically changed in recent decades and functional beverages now have a strong position in the market. The majority of these beverages are produced using simple processes that use raw products, such as cereals, legumes, fruits, and nuts, among others, and these are known to be frequently contaminated with mycotoxins. This review is focused on the occurrence of these toxic compounds in plant-based milks, fruit juices, and herbal teas. The fate of the toxins during processing is discussed to establish the potential risk posed by the consumption of these kind of beverages regarding mycotoxin uptake.

Evaluation of acute and chronic exposure to aflatoxin B1 in indigenous women of the Huasteca Potosina, Mexico

Aflatoxin B₁ (AFB₁) is one of the most studied mycotoxins due to its high occurrence in food and its hepatotoxic, immunosuppressive, carcinogenic, childhood growth, genotoxic, mutagenic, and teratogenic effects in humans and animals. Exposure to AFB₁ is reported to be both, acute and chronic; the main exposure pathway to AFB₁ is through the intake of contaminated food. In Mexico, although the reports of several studies addressing the problem of aflatoxins in maize and other foods, the evidence has been centered on exposure to AFB₁ and to the quantification of the Aflatoxins themselves, but there is null evidence about genotoxic effects of aflatoxins in vulnerable populations. Therefore, this study focused on assessing chronic AFB₁ exposure through the AFB₁-lys biomarker adduct and acute exposure through total AFB₁-DNA adducts in women from a rural indigenous community in the Huasteca Potosina (Mexico). A hundred percent of the studied population presented total AFB₁-DNA and AFB₁-lys adducts in concentrations of 1.08 (0.48-1.34) μmol of adduct/mol of DNA and 2.33 (1.08-102.6) pg/mg of albumin respectively (median (min-max)). Thus, continuous monitoring and important changes in regulations are desired and recommended. The results in this study provide enough evidence to support the toxic effects that the exposure to AFB₁ represents, as well as the population risk that it poses, and in the same sense, the current need to create an intervention program that directly influences the control of the sources of exposure in order to reduce it.

Untargeted metabolomics as a hypothesis-generation tool in plant protection product discovery: Highlighting the potential of trehalose and glycerol metabolism of fungal conidiospores as novel targets

INTRODUCTION

The production of high quality and safe food represents a main priority for the agri-food sector in the effort to sustain the exponentially growing human population. Nonetheless, there are major challenges that require the discovery of new, alternative, and improved plant protection products (PPPs). Focusing on fungal plant pathogens, the dissection of mechanisms that are essential for their survival provides insights that could be exploited towards the achievement of the aforementioned aim. In this context, the germination of fungal spores, which are essential structures for their dispersal, survival, and pathogenesis, represents a target of high potential for PPPs. To the best of our knowledge, no PPPs that target the germination of fungal spores currently exist.

OBJECTIVES

Within this context, we have mined for changes in the metabolite profiles of the model fungus Aspergillus nidulans FGSC A4 conidiospores during germination, in an effort to discover key metabolites and reactions that could potentially become targets of PPPs.

METHODS

Untargeted GC/EI-TOF/MS metabolomics and multivariate analyses were employed to monitor time-resolved changes in the metabolomes of germinating A. nidulans conidiospores.

RESULTS

Analyses revealed that trehalose hydrolysis plays a pivotal role in conidiospore germination and highlighted the osmoregulating role of the sugar alcohols, glycerol, and mannitol.

CONCLUSION

The ineffectiveness to introduce active ingredients that exhibit new mode(s)-of-action as fungicides, dictates the urge for the discovery of PPPs, which could be exploited to combat major plant protection issues. Based on the crucial role of trehalose hydrolysis in conidiospore dormancy breakage, and the subsequent involvement of glycerol in their germination, it is plausible to suggest their biosynthesis pathways as potential novel targets for the next-generation antifungal PPPs. Our study confirmed the applicability of untargeted metabolomics as a hypothesis-generation tool in PPPs' research and discovery.

Advances in Analysis and Detection of Major Mycotoxins in Foods

Mycotoxins are the most widely studied biological toxins, which contaminate foods at very low concentrations. This review describes the emerging extraction techniques and the current and alternatives analytical techniques and methods that have been used to successfully detect and identify important mycotoxins. Some of them have proven to be particularly effective in not only the detection of mycotoxins, but also in detecting mycotoxin-producing fungi. Chromatographic techniques such as high-performance liquid chromatography coupled with various detectors like fluorescence, diode array, UV, liquid chromatography coupled with mass spectrometry, and liquid chromatography-tandem mass spectrometry, have been powerful tools for analyzing and detecting major mycotoxins. Recent progress of the development of rapid immunoaffinity-based detection techniques such as immunoassays and biosensors, as well as emerging technologies like proteomic and genomic methods, molecular techniques, electronic nose, aggregation-induced emission dye, quantitative NMR and hyperspectral imaging for the detection of mycotoxins in foods, have also been presented.

Toxicological and Medical Aspects of Aspergillus-Derived Mycotoxins Entering the Feed and Food Chain

Due to Earth's changing climate, the ongoing and foreseeable spreading of mycotoxigenic Aspergillus species has increased the possibility of mycotoxin contamination in the feed and food production chain. These harmful mycotoxins have aroused serious health and economic problems since their first appearance. The most potent Aspergillus-derived mycotoxins include aflatoxins, ochratoxins, gliotoxin, fumonisins, sterigmatocystin, and patulin. Some of them can be found in dairy products, mainly in milk and cheese, as well as in fresh and especially in dried fruits and vegetables, in nut products, typically in groundnuts, in oil seeds, in coffee beans, in different grain products, like rice, wheat, barley, rye, and frequently in maize and, furthermore, even in the liver of livestock fed by mycotoxin-contaminated forage. Though the mycotoxins present in the feed and food chain are well documented, the human physiological effects of mycotoxin exposure are not yet fully understood. It is known that mycotoxins have nephrotoxic, genotoxic, teratogenic, carcinogenic, and cytotoxic properties and, as a consequence, these toxins may cause liver carcinomas, renal dysfunctions, and also immunosuppressed states. The deleterious physiological effects of mycotoxins on humans are still a first-priority question. In food production and also in the case of acute and chronic poisoning, there are possibilities to set suitable food safety measures into operation to minimize the effects of mycotoxin contaminations. On the other hand, preventive actions are always better, due to the multivariate nature of mycotoxin exposures. In this review, the occurrence and toxicological features of major Aspergillus-derived mycotoxins are summarized and, furthermore, the possibilities of treatments in the medical practice to heal the deleterious consequences of acute and/or chronic exposures are presented.

Role of biological control agents and physical treatments in maintaining the quality of fresh and minimally-processed fruit and vegetables

Fruit and vegetables are an important part of human diets and provide multiple health benefits. However, due to the short shelf-life of fresh and minimally-processed fruit and vegetables, significant losses occur throughout the food distribution chain. Shelf-life extension requires preserving both the quality and safety of food products. The quality of fruit and vegetables, either fresh or fresh-cut, depends on many factors and can be determined by analytical or sensory evaluation methods. Among the various technologies used to maintain the quality and increase shelf-life of fresh and minimally-processed fruit and vegetables, biological control is a promising approach. Biological control refers to postharvest control of pathogens using microbial cultures. With respect to application of biological control for increasing the shelf-life of food, the term biopreservation is favored, although the approach is identical. The methods for screening and development of biocontrol agents differ greatly according to their intended application, but the efficacy of all current approaches following scale-up to commercial conditions is recognized as insufficient. The combination of biological and physical methods to maintain quality has the potential to overcome the limitations of current approaches. This review compares biocontrol and biopreservation approaches, alone and in combination with physical methods. The recent increase in the use of meta-omics approaches and other innovative technologies, has led to the emergence of new strategies to increase the shelf-life of fruit and vegetables, which are also discussed herein.

Alternariol induced proliferation in primary mouse keratinocytes and inflammation in mouse skin is regulated via PGE2/EP2/cAMP/p-CREB signaling pathway

Alternariol (AOH) is a mycotoxin that contaminates various food stuffs as well as animal feed and may cause toxicity after consumption. However, a dermal toxic potential of AOH has not been explored so far. In the present study, skin toxicity after topical exposure of AOH and the involved mechanism/s are revealed. Single topical application of different AOH doses (12.5, 25, 50 μg/animal) caused increased bi-fold thickness as well as hyperplasia and higher production of prostaglandin E2 (PGE₂) along with cAMP in the skin demonstrating its inflammatory potential. Western blot analysis showed that exposure of AOH lead to phosphorylation of CREB and increased the expression of COX-2, cyclin D1 as well as prostanoid EP2 receptor. Further studies on primary mouse keratinocytes (PMK) revealed that very low concentrations of AOH (50-500 nM) resulted in significant PMK proliferation. Additionally, using specific antagonist or agonist of prostanoid receptors, we delineated that EP2 receptor play a key role in AOH-induced PMKs proliferation. Collectively, our findings show that AOH can lead to dermal toxicity in mice by activating the EP2/cAMP/p-CREB signaling cascade.

Presence of mycotoxins in ready-to-eat food and subsequent risk assessment

A study on a set of ready-to-eat meals (n = 328) based on cereals, legumes, vegetables, fish and meat was carried out to determine the natural presence of twenty-seven mycotoxins by both liquid chromatography and gas chromatography coupled mass spectrometry in tandem (MS/MS) after QuEChERS extraction. The occurrence of mycotoxins was headed by cereal samples with 35% of samples contaminated by at least one mycotoxin followed by vegetables (32%), legumes (15%) and lastly, 9% of fish and meat samples were contaminated. DON was the most detected mycotoxin in vegetables, meat, fish and cereals with an incidence of 13% 18% 19% and 60%, respectively, and the highest mean levels were found in fish (1.19 μg/kg) and vegetable (1.53 μg/kg), respectively. The highest levels means were for HT-2 toxin ranging from 4.03 to 7.79 μg/kg, in cereal and legume samples respectively. In this last, HT-2 toxin was also the most prevalent (54%). In meat samples, OTA resulted with highest value with 8.09 μg/kg. Likewise, PCA analysis revealed a high correlation between the mycotoxins and the food groups analyzed. The findings indicate that there is no toxicological concern associated with exposure to mycotoxins for consumers as all levels were in accordance with the legislation.

Evaluation of Mycotoxin Residues on Ready-to-Eat Food by Chromatographic Methods Coupled to Mass Spectrometry in Tandem

Simultaneous determination of twenty-seven mycotoxins in ready-to-eat food samples using “Quick Easy Cheap Rough and Safe” (QuEChERS) extraction and chromatographic methods coupled to mass spectrometry in tandem is described in this study. Mycotoxins included in this survey were aflatoxins (B₁, B₂, G₁, G₂), enniatins (A, A₁, B, B₁), beauvericin (BEA), fumonisins (FB₁, FB₂), sterigmatocystin (STG), deoxynivalenol (DON), 3-acetyl-deoxynivalenol (3-ADON), 15-acetyl-deoxynivalenol (15-ADON), nivalenol (NIV), neosolaniol (NEO), diacetoxyscirpenol (DAS), fusarenon-X (FUS-X), zearalenone (ZEA), α-zearalanol (αZAL), β-zearalenone (βZAL), α-zearalenol (αZOL), β-zearalenol (βzol), T2, and HT-2 toxin. The method showed satisfactory extraction results with recoveries ranging from 63 to 119% for the different food matrix samples. Limits of detection (LODS) and quantification (LOQs) were between 0.15⁻1.5 µg/kg and 0.5⁻5 µg/kg, respectively. The method was successfully applied to the analysis of 25 ready-to-eat food samples. Results showed presence of deoxynivalenol at 36% of samples (2.61⁻21.59 µg/kg), enniatin B at 20% of samples (9.83⁻86.32 µg/kg), HT-2 toxin at 16% of samples (9.06⁻34.43 µg/kg), and aflatoxin G₂ at 4% of samples (2.84 µg/kg). Mycotoxins were detected mainly in ready-to-eat food samples prepared with cereals, vegetables, and legumes, even at levels below those often obtained from raw food.

Fungal diversity in the grapes-to-wines chain with emphasis on Penicillium species

The aim of this work was the description of surface and endogenous mycobiota colonisation of grapes, fresh grape juice, grape must, and wine primarily focused to the current spectrum of the penicillium species. One sample of white grape variety Palava and one sample of blue grape variety Dornfelder were collected in Small Carpathian wine growing region of Slovakia in the year 2017. Direct plating of grapes on agar plates was used for analysis of surface mycobiota of grapes while surface sterilsed grapes were used for endogenous mycobiota analysis. Mycobiota of juice, must, and wine was analysed by plate dilution method. Overall, we isolated 148 strains belonging to 13 genera of filamentous microscopic fungi and Mycelia sterilia from grape variety Palava, while the most frequent was Alternaria. Alternaria was the most common genus in the surface and endogenous colonisation with an average relative density 50% and 73.6%, respectively. A total of 2 species of Penicillium were detected from the grapes to wine, potentially toxigenic Penicillium expansum and P. chrysogenum. A total of 39 strains belonging to 6 genera and Mycelia sterilia were identified from grape variety Dornfelder. The most abundant genus was also Alternaria (51.3%), followed by Penicillium (12.8%). Alternaria was the most common genus in the surface and endogenous colonisation  and fresh grape juice with an average relative density from 20% (grape juice) to 71% (endogenous colonisation of grapes). A total of 3 species of Penicillium were detected from the grapes to wine, where Penicillium expansum were detected most commonly. In the second part of our work some selected isolates were tested to the ability to produce mycotoxins such as patulin, citrinin, and roquefortin C in in vitro condition by thin layer chromatography method. All tested  strains of Penicillium species were able to produce at least one mycotoxin. 

PR Toxin - Biosynthesis, Genetic Regulation, Toxicological Potential, Prevention and Control Measures: Overview and Challenges

Out of the various mycotoxigenic food and feed contaminant, the fungal species belonging to Penicillium genera, particularly Penicillium roqueforti is of great economic importance, and well known for its crucial role in the manufacturing of Roquefort and Gorgonzola cheese. The mycotoxicosis effect of this mold is due to secretion of several metabolites, of which PR toxin is of considerable importance, with regard to food quality and safety challenges issues. The food products and silages enriched with PR toxin could lead into damage to vital internal organs, gastrointestinal perturbations, carcinogenicity, immunotoxicity, necrosis, and enzyme inhibition. Moreover, it also has the significant mutagenic potential to disrupt/alter the crucial processes like DNA replication, transcription, and translation at the molecular level. The high genetic diversities in between the various strains of P. roqueforti persuaded their nominations with Protected Geographical Indication (PGI), accordingly to the cheese type, they have been employed. Recently, the biosynthetic mechanism and toxicogenetic studies unraveled the role of ari1 and prx gene clusters that cross-talk with the synthesis of other metabolites or involve other cross-regulatory pathways to negatively regulate/inhibit the other biosynthetic route targeted for production of a strain-specific metabolites. Interestingly, the chemical conversion that imparts toxic properties to PR toxin is the substitution/oxidation of functional hydroxyl group (-OH) to aldehyde group (-CHO). The rapid conversion of PR toxin to the other derivatives such as PR imine, PR amide, and PR acid, based on conditions available reflects their unstability and degradative aspects. Since the PR toxin-induced toxicity could not be eliminated safely, the assessment of dose-response and other pharmacological aspects for its safe consumption is indispensable. The present review describes the natural occurrences, diversity, biosynthesis, genetics, toxicological aspects, control and prevention strategies, and other management aspects of PR toxin with paying special attention on economic impacts with intended legislations for avoiding PR toxin contamination with respect to food security and other biosafety purposes.

A critical review of producers of small lactone mycotoxins: patulin, penicillic acid and moniliformin

A very large number of filamentous fungi has been reported to produce the small lactone mycotoxins patulin, penicillic acid and moniliformin. Among the 167 reported fungal producers of patulin, only production by 29 species could be confirmed. Patulin is produced by 3 Aspergillus species, 3 Paecilomyces species, 22 Penicillium species from 7 sections of Penicillium, and one Xylaria species. Among 101 reported producers of penicillic acid, 48 species could produce this mycotoxin. Penicillic acid is produced by 23 species in section Aspergillus subgenus Circumdati section Circumdati, by Malbranchea aurantiaca and by 24 Penicillium species from 9 sections in Penicillium and one species that does not actually belong to Penicillium (P. megasporum). Among 40 reported producers of moniliformin, five species have been regarded as doubtful producers of this mycotoxin or are now regarded as taxonomic synonyms. Moniliformin is produced by 34 Fusarium species and one Penicillium species. All the accepted producers of patulin, penicillic acid and moniliformin were revised according to the new one fungus – one name nomenclatural system, and the most recently accepted taxonomy of the species.

Rapid Assessment of the Toxicity of Fungal Compounds Using Luminescent Vibrio qinghaiensis sp. Q67

Most tropical fruits after harvest are very perishable because of fungal infection. Since some pathogenic fungi can produce hazardous compounds such as mycotoxins, novel rapid and effective methods to assess those hazardous compounds are urgently needed. Herein we report that Vibrio qinghaiensis sp. Q67, a luminescent bacterium, can be used to rapidly assess the toxicities of mycotoxins and cultures from mycotoxin-producing pathogens. A good correlation (R² > 0.98) between concentrations of the mycotoxins (fumonisin B1, deoxynivalenol, zearalenone, ochratoxin A, patulin, and citrinin) and the luminous intensity of V. qinghaiensis sp. Q67 was obtained. Furthermore, significant correlations (R² > 0.96) between the amount of mycotoxin and the luminous intensity from the cultures of 10 major mycotoxin-producing pathogens were also observed. In addition, Fusarium proliferatum (half-maximal inhibitory concentration (IC₅₀) = 17.49%) exhibited greater luminescence suppression than Fusarium semitectum (IC₅₀ = 92.56%) or Fusarium oxysporum (IC₅₀ = 28.61%), which was in agreement with the existing higher levels of fumonisin B1, fumonisin B2, and deoxynivalenol, which were measured by high-performance liquid chromatography-tandem mass spectrometry. These results suggest that V. qinghaiensis sp. Q67 is a promising alternative for the rapid evaluation of the toxicity of fungal mycotoxins.

Studies on the Presence of Mycotoxins in Biological Samples: An Overview

Mycotoxins are fungal secondary metabolites with bioaccumulation levels leading to their carry-over into animal fluids, organs, and tissues. As a consequence, mycotoxin determination in biological samples from humans and animals has been reported worldwide. Since most mycotoxins show toxic effects at low concentrations and considering the extremely low levels present in biological samples, the application of reliable detection methods is required. This review summarizes the information regarding the studies involving mycotoxin determination in biological samples over the last 10 years. Relevant data on extraction methodology, detection techniques, sample size, limits of detection, and quantitation are presented herein. Briefly, liquid-liquid extraction followed by LC-MS/MS determination was the most common technique. The most analyzed mycotoxin was ochratoxin A, followed by zearalenone and deoxynivalenol—including their metabolites, enniatins, fumonisins, aflatoxins, T-2 and HT-2 toxins. Moreover, the studies were classified by their purpose, mainly focused on the development of analytical methodologies, mycotoxin biomonitoring, and exposure assessment. The study of tissue distribution, bioaccumulation, carry-over, persistence and transference of mycotoxins, as well as, toxicokinetics and ADME (absorption, distribution, metabolism and excretion) were other proposed goals for biological sample analysis. Finally, an overview of risk assessment was discussed.

Occurrence, Toxicity, and Analysis of Major Mycotoxins in Food

Mycotoxins are toxic secondary metabolites produced by certain filamentous fungi (molds). These low molecular weight compounds (usually less than 1000 Daltons) are naturally occurring and practically unavoidable. They can enter our food chain either directly from plant-based food components contaminated with mycotoxins or by indirect contamination from the growth of toxigenic fungi on food. Mycotoxins can accumulate in maturing corn, cereals, soybeans, sorghum, peanuts, and other food and feed crops in the field and in grain during transportation. Consumption of mycotoxin-contaminated food or feed can cause acute or chronic toxicity in human and animals. In addition to concerns over adverse effects from direct consumption of mycotoxin-contaminated foods and feeds, there is also public health concern over the potential ingestion of animal-derived food products, such as meat, milk, or eggs, containing residues or metabolites of mycotoxins. Members of three fungal genera, Aspergillus, Fusarium, and Penicillium, are the major mycotoxin producers. While over 300 mycotoxins have been identified, six (aflatoxins, trichothecenes, zearalenone, fumonisins, ochratoxins, and patulin) are regularly found in food, posing unpredictable and ongoing food safety problems worldwide. This review summarizes the toxicity of the six mycotoxins, foods commonly contaminated by one or more of them, and the current methods for detection and analysis of these mycotoxins.

Mitigation of Patulin in Fresh and Processed Foods and Beverages

Patulin is a mycotoxin of food safety concern. It is produced by numerous species of fungi growing on fruits and vegetables. Exposure to the toxin is connected to issues neurological, immunological, and gastrointestinal in nature. Regulatory agencies worldwide have established maximum allowable levels of 50 µg/kg in foods. Despite regulations, surveys continue to find patulin in commercial food and beverage products, in some cases, to exceed the maximum limits. Patulin content in food can be mitigated throughout the food processing chain. Proper handling, storage, and transportation of food can limit fungal growth and patulin production. Common processing techniques including pasteurisation, filtration, and fermentation all have an effect on patulin content in food but individually are not sufficient safety measures. Novel methods to remove or detoxify patulin have been reviewed. Non-thermal processing techniques such as high hydrostatic pressure, UV radiation, enzymatic degradation, binding to microorganisms, and chemical degradation all have potential but have not been optimised. Until further refinement of these methods, the hurdle approach to processing should be used where food safety is concerned. Future development should focus on determining the nature and safety of chemicals produced from the breakdown of patulin in treatment techniques.

Aflatoxins: Implications on Health

Environmental occurrence of Aspergillus and other fungal spores are hazardous to humans and animals. They cause a broad spectrum of clinical complications. Contamination of aflatoxins in agri-food and feed due to A. flavus and A. parasiticus result in toxicity in humans and animals. Recent advances in aspergillus genomics and aflatoxin management practices are encouraging to tackle the challenges posed by important aspergillus species.

Effects of patulin and ascladiol on porcine intestinal mucosa: An ex vivo approach

Patulin (PAT) is a secondary metabolite mainly produced by Aspergillus and Penicillium that is frequently found contaminating apples and rotten fruits. Patulin can be transformed in potencially less toxic compounds such as ascladiol (ASC). Toxic effects of patulin were described in rats and in in vitro models, however concerning ascladiol, data are restricted to metabolic pathways. The aim of the present study was to evaluate the effects of different concentrations of PAT (10 μM, 30 μM, 100 μM) and ASC (30 μM, 100 μM) on intestinal tissue using the jejunal explant model. Explants from pigs were exposed for 4 h to PAT and ASC and after this period were processed for histological, morphometrical and immunohistochemical analysis. Mild histological changes were observed in jejunal explants exposed to PAT and ASC, however no significant difference in the lesional score or villi height was observed between the PAT/ASC-groups and the control. Also, explants exposed to 100 μM of PAT showed a significant decrease in goblet cells density and a significant increase in cell apoptosis. These results indicate that high levels of patulin can induce mild toxic effects on intestinal mucosa whereas ascladiol apparently is non-toxic to intestinal tissue.

Influence of Butylated Hydroxyanisole on the Growth, Hyphal Morphology, and the Biosynthesis of Fumonisins in Fusarium proliferatum

Fusarium proliferatum as a common fungus pathogen in foods can produce toxic fumonisins, which can cause animal diseases and increase risks of human cancers. On contrary, butylated hydroxyanisole (BHA) as a synthetic antioxidant offers a clue for preventing growth of fungal species and inhibiting production of mycotoxins. Unfortunately, information of the inhibitory mechanism of BHA on Fusarium species is still limited. In this study, influence of BHA treatment on growth and inhibition of fumonisin production in relation to the expression of the fumonisin biosynthesis-related genes of the F. proliferatum ZYF was investigated, which revealed that BHA had a negative influence on growth and fumonisin production of F. proliferatum. To further elucidate the mechanism of BHA on the growth of F. proliferatum, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to examine the F. proliferatum hyphae. The BHA treatment induced the loss of cytoplasm and cellular constituents, as well as distortion of mycelia, but it did not directly degrade the fumonisin. Furthermore, the BHA treatment markedly inhibited the expressions of FUM1 (a polyketide synthase encoding gene) and FUM8 (an aminotransferase encoding gene) genes, which resulted in the depression of metabolic pathway of F. proliferatum. The transcriptional analyses of the FUM1 and FUM8 genes confirmed a correlation between the fumonisin production and its gene expression. This study provided some insights into mechanisms of production of fumonisin and feasible prevention to reduce fumonisin contamination in favor of human and animal health.