New perspective approaches in controlling fungi and mycotoxins in food using emerging and green technologies

Application of chitosan and other biopolymers based edible coatings containing essential oils as green and innovative strategy for preservation of perishable food products: A review

Deterioration of perishable foods due to fungal contamination and lipid peroxidation are the most threatened concern to food industry. Different chemical preservatives have been used to overcome these constrains; however their repetitive use has been cautioned owing to their negative impact after consumption. Therefore, attention has been paid to essential oils (EOs) because of their natural origin and proven antifungal and antioxidant activities. Many EO-based formulations have been in use but their industrial-scale application is still limited, possibly due to its poor solubility, vulnerability towards oxidation, and aroma effect on treated foods. In this sense, active food packaging using biopolymers could be considered as promising approach. The biopolymers can enhance the stability and effectiveness of EOs through controlled release, thus minimizes the deterioration of foods caused by fungal pathogens and oxidation without compromising their sensory properties. This review gives a concise appraisal on latest advances in active food packaging, particularly developed from natural polymers (chitosan, cellulose, cyclodextrins etc.), characteristics of biopolymers, and current status of EOs. Then, different packaging and their effectiveness against fungal pathogens, lipid-oxidation, and sensory properties with recent previous works has been discussed. Finally, effort was made to highlights their safety and commercialization aspects towards market solutions.

Efficacy of pterostilbene suppression on Aspergillus flavus growth, aflatoxin B1 biosynthesis and potential mechanisms

Aspergillus flavus, a widespread saprotrophic filamentous fungus, could colonize agricultural crops with aflatoxin contamination, which endangers food security and the agricultural economy. A safe, effective and environmentally friendly fungicide is urgently needed. Pterostilbene, a natural phytoalexin originated from Pterocarpus indicus Willd., Vaccinium spp. and Vitis vinifera L., has been reported to possess excellent antimicrobial activity. More importantly, it is quite safe and healthy. In our screening tests of plant polyphenols for the inhibition of A. flavus, we found that pterostilbene evidently inhibited mycelial growth of Aspergillus flavus (EC50 = 15.94 μg/mL) and the inhibitory effect was better than that of natamycin (EC50 = 22.01 μg/mL), which is a natural product widely used in food preservation. Therefore, we provided insights into the efficacy of pterostilbene suppression on A. flavus growth, aflatoxin B1 biosynthesis and its potential mechanisms against A. flavus in the present study. Here, pterostilbene at concentrations of 250 and 500 μg/mL could effectively inhibit the infection of A. flavus on peanuts. And the biosynthesis of the secondary metabolite aflatoxin B1 was also inhibited. The antifungal effects of pterostilbene are exerted by inducing a large amount of intracellular reactive oxygen species production to bring the cells into a state of oxidative stress, damaging cellular biomolecules such as DNA, proteins and lipids and destroying the integrity of the cell membrane. Taken together, our study strongly supported the fact that pterostilbene could be considered a safe and effective antifungal agent against A. flavus infection.

Detoxification of mycotoxins in agricultural products by non-thermal physical technologies: a review of the past five years

Mycotoxins produced by Aspergillus spp., Penicillium spp. and Fusarium spp. with small molecular weight and thermal stability, are highly toxic and carcinogenic secondary metabolites. Mycotoxins have caused widespread concern regarding food safety internationally because of their adverse effects on the health of humans and animals, and the major economic losses they cause. There is an urgent need to find ways to reduce or eliminate the impact of mycotoxins in food and feed without introducing new safety issues, or reducing nutritional quality. Non-thermal physical technology is the basis for new techniques to degrade mycotoxins, with great potential for practical detoxification applications in the food industry. Compared with conventional thermal treatments, non-thermal physical detoxification technologies are easier to apply and effective, with less adverse impact on the nutritional value of agricultural products. The advantages, limitations and development prospects of these new detoxification technologies are discussed. Further studies are recommended to standardize the treatment conditions for each detoxification technology, evaluate the safety of the degradation products, and to combine different detoxification technologies to achieve synergistic effects. This will facilitate realization of the great potential of the new technologies and the development of practical applications.

Chemical decontamination of foods using non-thermal plasma-activated water

The presence of chemical contaminants in foods and agricultural products is one of the major safety issues worldwide, posing a serious concern to human health. Nonthermal plasma (NTP) containing richly reactive oxygen and nitrogen species (RONS) has been trialed as a potential decontamination method. Yet, this technology comes with multiple downsides, including adverse effects on the quality of treated foods and limited exposure to entire surfaces on samples with hard-to-reach spots, further hindering real-life applications. Therefore, plasma-activated water (PAW) has been recently developed to facilitate the interactions between RONS and contaminant molecules in the liquid phase, allowing a whole surface treatment with efficient chemical degradation. Here, we review the recent advances in PAW utilized as a chemical decontamination agent in foods. The reaction mechanisms and the main RONS contributors involved in the PAW-assisted removal of chemical contaminants are briefly outlined. Also, the comprehensive effects of these treatments on food qualities (chemical and physical characteristics) and toxicological evaluation of PAW (in vitro and in vivo) are thoroughly discussed. Ultimately, we identified some current challenges and provided relevant suggestions, which can further promote PAW research for real-life applications in the future.

The natural occurrence, toxicity mechanisms and management strategies of Fumonisin B1：A review

Fumonisin B1 (FB1) contaminates various crops, causing huge losses to agriculture and livestock worldwide. This review summarizes the occurrence regularity, toxicity, toxic mechanisms and management strategies of FB1. Specifically, FB1 contamination is particularly serious in developing countries, humid and hot regions. FB1 exposure can produce different toxic effects on the nervous system, respiratory system, digestive system and reproductive system. Furthermore, FB1 can also cause systemic immunotoxicity. The mechanism of toxic effects of FB1 is to interfere with the normal pathway of sphingolipid de novo biosynthesis by acting as a competitive inhibitor of ceramide synthase. Meanwhile, the toxic products of sphingolipid metabolic disorders can cause oxidative stress and apoptosis. FB1 also often causes feed contamination by mixing with other mycotoxins, and then exerts combined toxicity. For detection, lateral flow dipstick technology and enzyme linked immunosorbent assay are widely used in the detection of FB1 in commercial feeds, while mainstream detection methods such as high performance liquid chromatography and liquid chromatography-mass spectrometry are widely used in the laboratory theoretical study of FB1. For purification means of FB1, some natural plant extracts (such as Zingiber officinale and Litsea Cubeba essential oil) and their active compounds have been proved to inhibit the toxic effects of FB1 and protect livestock due to their antifungal and antioxidant effects. Natural plant extract has the advantages of high efficiency, low cost and no contamination residue. This review can provide information for comprehensive understanding of FB1, and provide reference for formulating reasonable treatment and management strategies in livestock production.

Antifungal Effect of Metabolites from a New Strain Lactiplantibacillus Plantarum LPP703 Isolated from Naturally Fermented Yak Yogurt

The antifungal effect of metabolites produced by a new strain of Lactiplantibacillus (Lpb.) plantarum LPP703, isolated from naturally fermented yak yogurt, was investigated. The results showed that Lpb. plantarum LPP703 significantly inhibited four fungal species, including Penicillium sp., Rhizopus delemar, Aspergillus flavus, and Aspergillus niger. The metabolites produced after 20 h of Lpb. plantarum LPP703 fermentation showed the highest antifungal activity against Penicillium sp. Compared with the control group, the Lpb. plantarum LPP703 metabolites-treated Penicillium sp. spores were stained red by propidium iodide, indicating that the cell membrane of the fungal spores was damaged. Moreover, the antifungal effect of the Lpb. plantarum LPP703 metabolites on Penicillium sp. was not changed after heating or treatment with various proteases, but showed a sharp decrease when the pH value was regulated to 5.0 or above. The oleamide, trans-cinnamic acid, and citric acid were the three most abundant in the Lpb. plantarum LPP703 metabolites. Molecular docking predicated that the oleamide interacted with the active site of lanosterol 14-alpha-demethylase (CYP51, a crucial enzyme for fungal membrane integrity) through hydrogen bonds and had the lowest docking score, representing the strongest binding affinity to CYP51. Taken together, the metabolites from a new strain of Lpb. plantarum, LPP703, had potent antifungal activity against Penicillium sp., which might be associated with the damage of the active ingredient to fungal membrane integrity. This study indicated that Lpb. plantarum LPP703 and its metabolites might act as biological control agents to prevent fungal growth in the food industry.

Anti-toxicogenic fungi and toxin-reducing effects of bacillomycin D in combination with fungicides

Mycotoxins are toxic secondary metabolites produced by fungus including Aspergillus and Fusarium. They can contaminate food and cause major health issues. Bacillomycin D (BD) is a natural antimicrobial lipopeptide generated by Bacillus that has excellent antifungal capabilities, but its high price prevents it from being widely used. Chemically produced and essential oil-based fungicides are also currently the most frequent types. In the study, the effects of combining BD with two types of fungicides on the growth of toxicogenic fungi as well as the generation of deoxynivalenol (DON) and fumonisin B₁ (FB₁) were examined. It was discovered that BD was more effective in suppressing molds than the other two types of fungicides, and it could be combined with synthetic or essential oil-based fungicides to provide a synergistic or additive effect. BD 31.25 μg/mL + Thymol (Thy) 7.81 μg/mL and BD 11.45 μg/mL + Cinnamon oil (Cin) 3.90 μg/mL inhibited F. graminearum, respectively. The combination of BD+Thy and BD+Cin at this concentration considerably reduced 60%-80% spore germination, when DON dropped below 300 ng/L. Furthermore, both combinations suppressed F. moniliforme growth and FB₁ synthesis in a dose-dependent manner at lower concentrations. At an action dose of 2 MIC, FB₁ production might be reduced to less than 100 ng/L. Our findings indicated that BD might interact synergistically with various fungicides, suggesting that it could be useful in the field of antifungal and toxicity reduction in food.

Relevant Fusarium Mycotoxins in Malt and Beer

Mycotoxins are secondary fungal metabolites of high concern in the food and feed industry. Their presence in many cereal-based products has been numerously reported. Beer is the most consumed alcoholic beverage worldwide, and Fusarium mycotoxins originating from the malted and unmalted cereals might reach the final product. This review aims to describe the possible Fusarium fungi that could infect the cereals used in beer production, the transfer of mycotoxins throughout malting and brewing as well as an insight into the incidence of mycotoxins in the craft beer segment of the industry. Studies show that germination is the malting step that can lead to a significant increase in the level of all Fusarium mycotoxins. The first step of mashing (45 °C) has been proved to possess the most significant impact in the transfer of hydrophilic toxins from the grist into the wort. However, during fermentation, a slight reduction of deoxynivalenol, and especially of zearalenone, is achieved. This review also highlights the limited research available on craft beer and the occurrence of mycotoxins in these products.

Essential Oil Nanoemulsion as Eco-Friendly and Safe Preservative: Bioefficacy Against Microbial Food Deterioration and Toxin Secretion, Mode of Action, and Future Opportunities

Microbes are the biggest shareholder for the quantitative and qualitative deterioration of food commodities at different stages of production, transportation, and storage, along with the secretion of toxic secondary metabolites. Indiscriminate application of synthetic preservatives may develop resistance in microbial strains and associated complications in human health with broad-spectrum environmental non-sustainability. The application of essential oils (EOs) as a natural antimicrobial and their efficacy for the preservation of foods has been of present interest and growing consumer demand in the current generation. However, the loss in bioactivity of EOs from fluctuating environmental conditions is a major limitation during their practical application, which could be overcome by encapsulating them in a suitable biodegradable and biocompatible polymer matrix with enhancement to their efficacy and stability. Among different nanoencapsulated systems, nanoemulsions effectively contribute to the practical applications of EOs by expanding their dispersibility and foster their controlled delivery in food systems. In line with the above background, this review aims to present the practical application of nanoemulsions (a) by addressing their direct and indirect (EO nanoemulsion coating leading to active packaging) consistent support in a real food system, (b) biochemical actions related to antimicrobial mechanisms, (c) effectiveness of nanoemulsion as bio-nanosensor with large scale practical applicability, (d) critical evaluation of toxicity, safety, and regulatory issues, and (e) market demand of nanoemulsion in pharmaceuticals and nutraceuticals along with the current challenges and future opportunities.

Effect of high hydrostatic pressure on the edible quality, health and safety attributes of plant-based foods represented by cereals and legumes: a review

Consumers today are increasingly willing to reduce their meat consumption and adopt plant-based alternatives in their diet. As a main source of plant-based foods, cereals and legumes (CLs) together could make up for all the essential nutrients that humans consume daily. However, the consumption of CLs and their derivatives is facing many challenges, such as the poor palatability of coarse grains and vegetarian meat, the presence of anti-nutritional factors, and allergenic proteins in CLs, and the vulnerability of plant-based foods to microbial contamination. Recently, high hydrostatic pressure (HHP) technology has been used to tailor the techno-functionality of plant proteins and induce cold gelatinization of starch in CLs to improve the edible quality of plant-based products. The nutritional value (e.g., the bioavailability of vitamins and minerals, reduction of anti-nutritional factors of legume proteins) and bio-functional properties (e.g., production of bioactive peptides, increasing the content of γ-aminobutyric acid) of CLs were significantly improved as affected by HHP. Moreover, the food safety of plant-based products could be significantly improved as well. HHP lowered the risk of microbial contamination through the inactivation of numerous microorganisms, spores, and enzymes in CLs and alleviated the allergy symptoms from consumption of plant-based foods.

A review of recent advances in the decontamination of mycotoxin and inactivation of fungi by ultrasound

Innovative technologies for the pasteurization of food products have increased due to the global demand for higher-quality food products. In this regard, the current article aimed to provide an overview regarding the latest research on US application in the decontamination of fungi in food products and highlight the parameters influencing the effectiveness of this method. Therefore, the related article with inactivation of fungi and mycotoxins by ultrasound among last four years (2018-2021) by using terms such as 'mycotoxin,' 'inactivation,' 'ultrasound,' 'decontamination' among some international databases such as PubMed, Web of Science, Embase and Google Scholar" was retrieved. Ultrasound (US) is considered a non-thermal decontamination method for food products. In US, the release of energy due to the acoustic phenomenon destroys microorganisms. This technology is advantageous as it is inexpensive, eco-friendly, and does not negatively affect food products' food structure and organoleptic properties. The influence of the US on food structure and organoleptic properties dramatically depends on the intensity and energy density applied In addition, it can preserve higher levels of ascorbic acid, lycopene, and chlorophyll in sonicated food products. The treatment conditions, including frequency, intensity, duration, temperature, and processing pressure, influence the effectiveness of decontamination. However, US displays synergistic or antagonistic effects on bacteria, yeasts, molds, and mycotoxins when combined with other types of decontamination methods such as chemical and thermal approaches. Thus, further research is needed to clarify these effects. Overall, the application of US methods in the food industry for decreasing the microbial content of food products during processing has been applied. However, the use of US with other techniques needs to be studied further.

A global systematic review and meta-analysis of concentration and prevalence of mycotoxins in birds' egg

In the current study, the concentration and prevalence of birds' egg's mycotoxins among 11 articles (66 studies) based on countries, part of eggs, and type of mycotoxins subgroups were meta-analyses using a random-effect model. The order of mycotoxin according to concentration of mycotoxin was Deoxynivalenol (20.083 μg/kg) > Zearalenone (2.065 μg/kg) > Enniatin (1.120 μg/kg) > Total aflatoxin (0.371 μg/kg) > Beauvericin (0.223 μg/kg) > Ochratoxins (0.087 μg/kg) > Citrinin (0.010 μg/kg). Further, the mycotoxins' concentration in the yolk part (2.070 μg/kg) was higher than the mixed eggs (0.283 μg/kg). The rank order of mycotoxin based on country was China (14.990 μg/kg) > Cameroon (7.594 μg/kg) > Thailand (1.870 μg/kg) > Finland (0.920 μg/kg) > Iran (0.312 μg/kg) > Jordan (0.202 μg/kg) > Belgium (0.183 μg/kg) > Spain ( South Korea ( DON (85.00%) > AFT (20.15%) > OT (16.00%). The overall prevalence of mycotoxin was equal to 29.65%. Also, the concentration of mycotoxins in China and Cameroon was higher than in other countries. Therefore, the monitoring programs to reduce mycotoxins in bird eggs consumed in some countries such as China and Cameroon should be considered.

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.

Recent advances on the efficacy of essential oils on mycotoxin secretion and their mode of action

Essential oils, as extracted compounds from plants, are volatile and aromatic liquids which their unique aromatic compounds give each essential oil its distinctive essence. Fungi toxins can induce various adverse health effects like allergy, cancer, and immunosuppression. Moreover, fungal spoilage impacts pharmaceutical and food industries economic state. A drop in the utilization of synthetic compounds as food prophylaxis has occurred due to several factors such as hygiene agents' alerts and stricter legal regulations. Therefore, the applications of natural substances such as essential oils have increased in recent years. Oregano, cinnamon, thyme, rosemary, fennel, clove, palmarosa, and eucalyptus have been the highest employed essential oils against mycotoxigenic fungi and their mycotoxins in studies conducted in the past decade. Essential oils inhibit fungi growth and mycotoxin synthesis via diverse pathways including modified fungal growth rate and extended lag phase, disruption of cell permeability, disruption of the electron transport chain and manipulating gene expression patterns and metabolic processes. In the present review, we will investigate the implications and efficacy of essential oils in preventing the growth of mycotoxigenic fungi, eliminating mycotoxins and their mechanism of actions conducted in the last decade. HighlightsThe most investigated toxigenic genera are Aspergillus, Fusarium and Penicillium Spp.AB1, AG1, OTA and AB2 are the most frequently studied toxinsOregano, cinnamon and thyme are mostly exploited EOs on toxigenic fungi & mycotoxinsOregano, thyme & cinnamon are the most significant antifungals on toxigenic generaCinnamon, oregano & cinnamaldehyde are the fittest antimycotoxins on DON, OTA & AFB1.