Reduction of Ochratoxin A Levels in White Wine by Yeast Treatments

Natural feed additives and bioactive supplements versus chemical additives as a safe and practical approach to combat foodborne mycotoxicoses

This review highlights the possible hazard of mycotoxins occurrence in foods and feeds in regards to foodborne diseases. The possible management of the risk of contamination of foods and feeds with mycotoxins by using natural feed additives, protecting against deleterious effects of mycotoxins or inhibiting the growth of fungi and mycotoxin production, is deeply investigated in the available literature and some effective measures for safe utilization of mycotoxin contaminated feed/food are proposed. The biological methods of decontamination, degradation or biotransformation of mycotoxins are deeply analyzed and discussed. Some natural antagonists against target fungi are also reviewed and a comparison is made with conventional fungicides for ensuring a safe prevention of mycotoxin contamination. The most common and useful chemical methods of mycotoxins decontamination of agricultural commodities or raw materials are also investigated, e.g., chemical additives inactivating or destroying and/or adsorbing mycotoxins as well as chemical additives inhibiting the growth of fungi and mycotoxin production. The practical use and safety of various kind of feed/food additives or herbal/biological supplements as possible approach for ameliorating the adverse effects of some dangerous mycotoxins is deeply investigated and some suggestions are given. Various possibilities for decreasing mycotoxins toxicity, e.g., by clarifying the mechanisms of their toxicity and using some target antidotes and vitamins as supplements to the diet, are also studied in the literature and appropriate discussions or suggestions are made in this regard. Some studies on animal diets such as low carbohydrate intake, increased protein content, calorie restriction or the importance of dietary fats are also investigated in the available literature for possible amelioration of the ailments associated with mycotoxins exposure. It could be concluded that natural feed additives and bioactive supplements would be more safe and practical approach to combat foodborne mycotoxicoses as compared to chemical additives.

Obtaining an aflatoxin-free and high-alcohol-content product using contaminated dried figs

Dried fig is one of the most susceptible products to aflatoxin contamination. Since contaminated figs are not suitable for human consumption and cannot be used for any other purposes, they are burned in a chemical incinerator. In this study, we investigated the potential of using aflatoxin-contaminated dried figs as a raw material for ethanol production. For this purpose, contaminated dried figs (and also uncontaminated controls) were subjected to fermentation and subsequent distillation, and the alcohol and aflatoxin levels were determined during the processes. In addition, volatile by-products in the final product were determined using gas chromatography. Contaminated and uncontaminated figs had similar fermentation and distillation patterns. Although fermentation caused significant decreases in aflatoxin levels, there were still toxin residues in the fermented samples at the end of the process. On the other hand, aflatoxins were completely removed in the first step of the distillation. There were minor differences between the volatile compound compositions of the distillates produced from contaminated and uncontaminated figs. It was shown that obtaining aflatoxin-free and high-alcohol-content product using contaminated dried figs is possible according to the lab-scale conducted studies. Aflatoxin-contaminated dried figs can be used as a sustainable raw material for producing ethyl alcohol that can be used as an ingredient of surface disinfectants and/or fuel additive for vehicles.

Fruit-Based Fermented Beverages: Contamination Sources and Emerging Technologies Applied to Assure Their Safety

The food and beverage market has become broader due to globalization and consumer claims. Under the umbrella of consumer demands, legislation, nutritional status, and sustainability, the importance of food and beverage safety must be decisive. A significant sector of food production is related to ensuring fruit and vegetable conservation and utilization through fermentation. In this respect, in this review, we critically analyzed the scientific literature regarding the presence of chemical, microbiological and physical hazards in fruit-based fermented beverages. Furthermore, the potential formation of toxic compounds during processing is also discussed. In managing the risks, biological, physical, and chemical techniques can reduce or eliminate any contaminant from fruit-based fermented beverages. Some of these techniques belong to the technological flow of obtaining the beverages (i.e., mycotoxins bound by microorganisms used in fermentation) or are explicitly applied for a specific risk reduction (i.e., mycotoxin oxidation by ozone). Providing manufacturers with information on potential hazards that could jeopardize the safety of fermented fruit-based drinks and strategies to lower or eliminate these hazards is of paramount importance.

Bio-control on the contamination of Ochratoxin A in food: Current research and future prospects

Ochratoxin A (OTA) is a secondary metabolite of several fungi and widely exists in various species of foods. The establishment of effective methods for OTA reduction is a key measure to ensure food processing and human health. This article reviews the current research of OTA reduction by biological approaches, summarizes the characteristics and efficiency of them, and evaluates the transformation pathways and metabolites safety of each degradation technology. The shortcomings of various methods are pointed out and future prospects are also proposed. Biological methods are the most promising approaches for OTA control. The defect of them is the long processing time and the growth of microbial cells may affect the product quality. Therefore, the control of OTA contamination should be conducted according to the food processing and their product types. Besides, it is significant for the exploitation of new strains, enzyme and novel adsorbents.

A Newly Isolated Alcaligenes faecalis ANSA176 with the Capability of Alleviating Immune Injury and Inflammation through Efficiently Degrading Ochratoxin A

Ochratoxin A (OTA) is one of the most prevalent mycotoxins that threatens food and feed safety. Biodegradation of OTA has gained much attention. In this study, an Alcaligenes faecalis strain named ANSA176, with a strong OTA-detoxifying ability, was isolated from donkey intestinal chyme and characterized. The strain ANSA176 could degrade 97.43% of 1 mg/mL OTA into OTα within 12 h, at 37 °C. The optimal levels for bacterial growth were 22–37 °C and pH 6.0–9.0. The effects of ANSA176 on laying hens with an OTA-contaminated diet were further investigated. A total of 36 laying hens were assigned to three dietary treatments: control group, OTA (250 µg/kg) group, and OTA + ANSA176 (6.2 × 10⁸ CFU/kg diet) group. The results showed that OTA decreased the average daily feed intake (ADFI) and egg weight (EW); meanwhile, it increased serum alanine aminopeptidase (AAP), leucine aminopeptidase (LAP), β2-microglobulin (β2-MG), immunoglobulin G (IgG), tumor necrosis factor-α (TNF-α), and glutathione reductase (GR). However, the ANSA176 supplementation inhibited or attenuated the OTA-induced damages. Taken together, OTA-degrading strain A. faecalis ANSA176 was able to alleviate the immune injury and inflammation induced by OTA.

Removal of Ochratoxin A from Red Wine Using Alginate-PVA-L. plantarum (APLP) Complexes: A Preliminary Study

The presence of ochratoxin A (OTA) in wines is a problem mainly due to the health damage it can cause to frequent drinkers. A method for removing these toxic substances from wine is the use of lactic acid bacteria with mycotoxin-adsorption capacities; however, their use is limited since a matrix in which they can be immobilized, to remove them after use, is needed. In this study, L. plantarum (LP) was encapsulated in a polymeric matrix composed of polyvinyl alcohol (PVA) and alginate, forming alginate–PVA–LP (APLP) complexes. Then, these complexes were characterized, and assays of OTA and phenol removal from wines were performed. As a result, it was observed that the APLP complexes at a concentration of 0.5 g mL⁻¹ removed over 50% of the OTA without substantially affecting the concentration of total phenols. In addition, it was determined that the presence of L. plantarum directly affected the ability to adsorb OTA from wines and did not decrease the total phenols. In conclusion, an alginate–PVA matrix allows immobilizing LP, and the complexes formed are an alternative for removing ochratoxin from contaminated wines.

Microbiological Decontamination of Mycotoxins: Opportunities and Limitations

The contamination of food and feeds with mycotoxins poses a global health risk to humans and animals, with major economic consequences. Good agricultural and manufacturing practices can help control mycotoxin contamination. Since these actions are not always effective, several methods of decontamination have also been developed, including physical, chemical, and biological methods. Biological decontamination using microorganisms has revealed new opportunities. However, these biological methods require legal regulations and more research before they can be used in food production. Currently, only selected biological methods are acceptable for the decontamination of feed. This review discusses the literature on the use of microorganisms to remove mycotoxins and presents their possible mechanisms of action. Special attention is given to Saccharomyces cerevisiae yeast and lactic acid bacteria, and the use of yeast cell wall derivatives.

Exogenous Calcium Ions Enhance Patulin Adsorption Capability of Saccharomyces cerevisiae

Patulin contamination is a serious issue that restricts the development of the global fruit processing industry. Yeasts adsorb patulin more effectively than other microbial adsorbents, and this adsorption process depends mainly on the function of the cell wall. The present study examined the effect of exogenous calcium, in concentrations ranging from 0 to 1 mol/L, on Saccharomyces cerevisiae cell wall structure and on patulin adsorption capability; the patulin adsorption capability of yeast was found to strengthen with an increase in exogenous calcium concentrations from 1 × 10^-4 to 1 × 10^-2 mol/L. Moreover, yeast cell wall thickness, β-1,3-glucan content, and the activities of the key catalytic enzymes β-1,3-glucanase and β-1,3-glycosyl transferase were all increased within this range. The results indicate that exogenous calcium activates key enzymes that are crucial for cell wall network formation and patulin adsorption capability.

Advances in Biodetoxification of Ochratoxin A-A Review of the Past Five Decades

Ochratoxin A (OTA) is a toxic secondary fungal metabolite that widely takes place in various kinds of foodstuffs and feeds. Human beings and animals are inevitably threatened by OTA as a result. Therefore, it is necessary to adopt various measures to detoxify OTA-contaminated foods and feeds. Biological detoxification methods, with better safety, flavor, nutritional quality, organoleptic properties, availability, and cost-effectiveness, are more promising than physical and chemical detoxification methods. The state-of-the-art research advances of OTA biodetoxification by degradation, adsorption, or enzymes are reviewed in the present paper. Researchers have discovered a good deal of microorganisms that could degrade and/or adsorb OTA, including actinobacteria, bacteria, filamentous fungi, and yeast. The degradation of OTA to non-toxic or less toxic OTα via the hydrolysis of the amide bond is the most important OTA biodegradation mechanism. The most important influence factor of OTA adsorption capacity of microorganisms is cell wall components. A large number of microorganisms with good OTA degradation and/or adsorption ability, as well as some OTA degradation enzymes isolated or cloned from microorganisms and animal pancreas, have great application prospects in food and feed industries.

The production of yeast cell wall using an agroindustrial waste influences the wall thickness and is implicated on the aflatoxin B1 adsorption process

The objectives of this study were: to evaluate the use of dry distillery grain soluble extract - DDGse to produce yeast biomass and to obtain cell wall (CW), to use the CW as an aflatoxin B₁ (AFB₁) adsorbent, to study the variation in the composition and thickness of the CW under the influence of DDGse to evaluate their implication on the adsorption process using transmission electron microscopy (TEM) and fourier-transform infrared spectroscopy (FITR). The production of biomass and CW were variable. The CW thickness values showed that S. boulardii strain grown in yeast extract peptone dextrose (YPD) or DDGse medium, with no significant differences observed. The thickness of the CW for S. cerevisiae (RC012 and VM014) were increased when the cells were grown in DDGse medium, the thickness was almost double compared to the values obtained in YPD medium. The spectra IR of each CW in the two culture media shown regions corresponding to polysaccharides, proteins and lipids. Cells grown in DDGse medium adsorbed more AFB₁ than those grown in YPD. The CW adsorbed more AFB₁ than the same amount of whole cell. Future studies should be done to determine the type of carbohydrates and the relationship between chitin - beta glucans responsible for mycotoxin adsorption.

Differential Adsorption of Ochratoxin A and Anthocyanins by Inactivated Yeasts and Yeast Cell Walls during Simulation of Wine Aging

The adsorption of ochratoxin A (OTA) by yeasts is a promising approach for the decontamination of musts and wines, but some potential competitive or interactive phenomena between mycotoxin, yeast cells, and anthocyanins might modify the intensity of the phenomenon. The aim of this study was to examine OTA adsorption by two strains of Saccharomyces cerevisiae (the wild strain W13, and the commercial isolate BM45), previously inactivated by heat, and a yeast cell wall preparation. Experiments were conducted using Nero di Troia red wine contaminated with 2 μg/L OTA and supplemented with yeast biomass (20 g/L). The samples were analyzed periodically to assess mycotoxin concentration, chromatic characteristics, and total anthocyanins over 84 days of aging. Yeast cell walls revealed the highest OTA-adsorption in comparison to thermally-inactivated cells (50% vs. 43% toxin reduction), whilst no significant differences were found for the amount of adsorbed anthocyanins in OTA-contaminated and control wines. OTA and anthocyanins adsorption were not competitive phenomena. Unfortunately, the addition of yeast cells to wine could cause color loss; therefore, yeast selection should also focus on this trait to select the best strain.

Ochratoxin A removal by Saccharomyces cerevisiae strains: effect of wine-related physicochemical factors

BACKGROUND

This study investigated the effect of some physicochemical parameters on the removal of ochratoxin A (OTA) by yeasts.

RESULTS

Two wild strains of Saccharomyces cerevisiae (W47 and Y28) were used to assess OTA removal under various conditions of temperature, pH, ethanol content and incubation time. All samples were analysed for OTA concentration by enzyme-linked immunosorbent assay (ELISA). In addition, yeast oenological traits were investigated: qualitative and technological traits were assessed on appropriate laboratory media, while the main products of microfermentation (sugars, ethanol, glycerol, acetic acid) were evaluated by Fourier transform infrared spectroscopy (FTIR). The results showed OTA reduction by 36-42% in cultures containing 100 g L⁻¹ ethanol incubated at pH 3.5 and 37 °C.

CONCLUSION

OTA removal was affected by contact time, pH and ethanol content, as it was increased at low pH and by 100 g L⁻¹ ethanol. Moreover, the phenomenon was reversible, as OTA was lowest after 4 days, then it was partially released in the medium.

Grapevine bunch rots: impacts on wine composition, quality, and potential procedures for the removal of wine faults

Bunch rot of grape berries causes economic loss to grape and wine production worldwide. The organisms responsible are largely filamentous fungi, the most common of these being Botrytis cinerea (gray mold); however, there are a range of other fungi responsible for the rotting of grapes such as Aspergillus spp., Penicillium spp., and fungi found in subtropical climates (e.g., Colletotrichum spp. (ripe rot) and Greeneria uvicola (bitter rot)). A further group more commonly associated with diseases of the vegetative tissues of the vine can also infect grape berries (e.g., Botryosphaeriaceae, Phomopsis viticola ). The impact these fungi have on wine quality is poorly understood as are remedial practices in the winery to minimize wine faults. Compounds found in bunch rot affected grapes and wine are typically described as having mushroom, earthy odors and include geosmin, 2-methylisoborneol, 1-octen-3-ol, 2-octen-1-ol, fenchol, and fenchone. This review examines the current state of knowledge about bunch rot of grapes and how this plant disease complex affects wine chemistry. Current wine industry practices to minimize wine faults and gaps in our understanding of how grape bunch rot diseases affect wine production and quality are also identified.

Substances for reduction of the contamination of feed by mycotoxins: a review

The global occurrence of mycotoxins is considered to be a major risk factor for human and animal health. Contamination of different agricultural commodities with mycotoxins still occurs despite the most strenuous prevention efforts. As a result, mycotoxin contaminated feed can cause serious disorders and diseases in farm animals. A number of approaches, such as physical and chemical detoxification procedures, have been used to counteract mycotoxins. However, only a few of them have practical application. A recent and promising approach to protect animals against the harmful effects of mycotoxin contaminated feed is the use of substances for reduction of the contamination of feed by mycotoxins. These substances, so-called mycotoxin binders (MB), are added to the diet in order to reduce the absorption of mycotoxins from the gastrointestinal tract and their distribution to blood and target organs, thus preventing or reducing mycotoxicosis in livestock. Recently, the use of such substances as technological feed additives has been officially allowed in the European Union. The efficacy of MB appears to depend on the properties of both the binder and the mycotoxin. Depending on their mode of action, these feed additives may act either by binding mycotoxins to their surface (adsorption), or by degrading or transforming them into less toxic metabolites (biotransformation). Biotransformation can be achieved by mycotoxin-degrading enzymes or by microorganisms producing such enzymes. Various inorganic adsorbents, such as hydrated sodium calcium aluminosilicate, zeolites, bentonites, clays, and activated carbons, have been tested and used as MB. An interesting alternative to inorganic adsorbents for the detoxification of mycotoxins is the use of organic binders, such as yeast cell wall components, synthetic polymers (cholestyramine, polyvinylpyrrolidone), humic substances and dietary fibres. This paper gives an overview of the current knowledge and situation in the field of MB. The most important types of MB, mechanism of their action, and their application as a part of general strategy to counteract mycotoxins are described in this review. Recent advances in the use and study of MB, as well as data of their in vitro and in vivo effectiveness are given. Problems, potential, current trends and perspectives associated with the use of MB are discussed as well in the review.

Occurrence of ochratoxin A in Southern Spanish generous wines under the denomination of Origin "Jerez-Xérès-Sherry and 'manzanilla' Sanlúcar de Barrameda"

The mycotoxin ochratoxin A (OTA) has toxic effects in animals; the most relevant of them is nephrotoxicity. OTA has also been classified as a possible carcinogen for humans (group 2B) by the International Agency for Research on Cancer (IARC). Therefore, exposure to OTA through contaminated food can represent health impairment to humans. The maximum permitted level for this mycotoxin in wine is 2.0 μg/L. The presence of OTA in Spanish wines produced using the traditional methods under the Denomination of Origin "Jerez-Xérès-Sherry andmanzanilla Sanlúcar de Barrameda" was evaluated by a High performance Liquid Chromatography method with fluorescence detection and immunoaffinity column purification. A recovery of 95.4% and a limit of detection and quantification of 0.009 μg/L and 0.02 μg/L respectively, were achieved. In manzanilla, fino, amontillado and oloroso wine, the mean OTA values were 0.042, 0.044, 0.144, and 0.319 μg/L, respectively. These levels are not different from other data given in the reference literature on white wines, although fino and manzanilla wines have very low OTA levels.

Biological strategies to counteract the effects of mycotoxins

Mycotoxins are fungal secondary metabolites that if ingested can cause a variety of adverse effects on both humans and animals, ranging from allergic responses to death. Therefore, exposure to mycotoxins should be minimized. A variety of physical, chemical, and biological methods have been developed for decontamination and/or detoxification of mycotoxins from contaminated foods and feeds. This overview details the latest developments in the biological control of both fungal infection and mycotoxin formation and describes the detoxification of many of the most important mycotoxins by microorganisms. This review also addresses the potential for use of microorganisms as mycotoxin binders in the gastrointestinal tract of both humans and animals, thereby reducing the potential deleterious effects of exposure to these toxins.