Effects of inulin and lactic acid bacteria strains on aflatoxin M1 detoxification in yoghurt

Starting with screening strains to construct synthetic microbial communities (SynComs) for traditional food fermentation

With the elucidation of community structures and assembly mechanisms in various fermented foods, core communities that significantly influence or guide fermentation have been pinpointed and used for exogenous restructuring into synthetic microbial communities (SynComs). These SynComs simulate ecological systems or function as adjuncts or substitutes in starters, and their efficacy has been widely verified. However, screening and assembly are still the main limiting factors for implementing theoretic SynComs, as desired strains cannot be effectively obtained and integrated. To expand strain screening methods suitable for SynComs in food fermentation, this review summarizes the recent research trends in using SynComs to study community evolution or interaction and improve the quality of food fermentation, as well as the specific process of constructing synthetic communities. The potential for novel screening modalities based on genes, enzymes and metabolites in food microbial screening is discussed, along with the emphasis on strategies to optimize assembly for facilitating the development of synthetic communities.

Detoxification of aflatoxin M1 in different milk types using probiotics

The aim of this study, research the potential use of probiotics in reducing the toxic effect of Aflatoxin M1 in cow milk, goat milk, sheep milk, and Phosphate-buffered saline (PBS). Milk and Phosphate-buffered saline were contaminated with Aflatoxin M1 at a concentration of 100 ppt. Then, various study groups were formed by adding Lactobacillus acidophilus DSMZ 20079, Lactobacillus rhamnosus GG, and Bifidobacterium bifidum DSMZ 20456 probiotic bacteria at a density of 108 CFU/ml. Then, working groups were stored for 1 day and Aflatoxin M1 levels were analyzed by an Enzyme-Linked Immunosorbent Assay kit. The binding level of Aflatoxin M1 by probiotic bacteria varies between 2.32-12.52% in Phosphate-buffered saline, 9.08-40.14% in cow milk, 15.01-38.01% in goat milk, and 32.49-42.90% in sheep milk. The highest binding level of Aflatoxin M1 was detected in sheep milk and the lowest in Phosphate-buffered saline. The binding ability of Aflatoxin M1 is ranked from highest to lowest in sheep milk, cow milk, and goat milk. The data obtained from this study is important because it is the first study to show that if sheep and goat milk is enriched with probiotics, it can reduce AFM1 exposure.

Potential probiotic strains with heavy metals and mycotoxins bioremoval capacity for application in foodstuffs

Heavy metals and mycotoxins in foodstuffs are one of the major concerns of our world nowadays. Food decontamination with the help of microbial biomass is a cheap, easy, efficient, and green method known as bioremoval. Probiotics are able to reduce the availability of heavy metals and toxins in food products. The purpose of this review is to summarize the probiotics and potential probiotics' interesting role in food bio-decontamination. After a brief glance at the definition of potential probiotic strains with bioremoval ability, LABs (lactic acid bacteria) are described as they are the most important groups of probiotics. After that, the role of the main probiotic and potential probiotic strains (Bacillus, Lactobacillus, Lactococcus, Enterococcus, Bifidobacterium, Pediococcus, Propionibacterium, Streptococcus, and Saccharomyces cerevisiae) for heavy metals and mycotoxins bioremoval are described. Additionally, the bioremoval mechanism and the effect of some factors in bioremoval efficiency are explained. Finally, the investigations about probiotic and contaminant stability are mentioned. It is worth mentioning that this review article can be exerted in different food and beverage industries to eliminate the heavy metals and mycotoxins in foodstuffs.

Fate of aflatoxins M1 and B1 within the period of production and storage of Tarkhineh: A traditional Persian fermented food

The objective of the study was to assess the amount of aflatoxin M₁ (AFM₁) and aflatoxin B₁ (AFB₁) during fermentation, drying, and storage of Tarkhineh-a traditional Persian fermented food-over four months. Tarkhineh samples were produced based on a traditional method. Various concentrations of AFB₁ (2.5, 5, 7.5, and 10 µg/kg) and AFM₁, stood at 0.25, 0.5, 0.75, and 1 µg/kg, were added to Iranian yogurt drink, called doogh, samples. Tarkhineh samples were evaluated for AFB₁ and AFM₁ on days 0, 2, 6, and 8 and also after drying and four months of storage. In cases of repeatability, recovery, and reproducibility, the high-performance liquid chromatography through fluorescence detector (HPLC-FD) method was successfully done to demonstrate aflatoxins (AFs) in Tarkhineh samples. The fermentation process had a considerable consequence on the reduction in AFM₁ and AFB₁ as compared to the control group, evidenced by 65.10%-81.20% and 55.80%-74.10%, respectively, after eight days of fermentation (p < .05). The highest reduction in AFB₁ existed in samples containing 2.5 µg/kg toxin, followed by 5, 7.5, and 10 µg/kg, respectively. A similar trend was found for AFM₁, as the highest concentration was found in samples containing 0.25 µg/kg toxin, followed by 0.5, 0.75, and 1 µg/kg, respectively.

Lactic Acid Bacteria from African Fermented Cereal-Based Products: Potential Biological Control Agents for Mycotoxins in Kenya

Cereals play an important role in global food security. Data from the UN Food and Agriculture Organization projects increased consumption of cereals from 2.6 billion tonnes in 2017 to approximately 2.9 billion tonnes by 2027. However, cereals are prone to contamination by toxigenic fungi, which lead to mycotoxicosis. The current methods for mycotoxin control involve the use of chemical preservatives. However, there are concerns about the use of chemicals in food preservation due to their effects on the health, nutritional quality, and organoleptic properties of food. Therefore, alternative methods are needed that are affordable and simple to use. The fermentation technique is based on the use of microorganisms mainly to impart desirable sensory properties and shelf-life extension. The lactic acid bacteria (LAB) are generally regarded as safe (GRAS) due to their long history of application in food fermentation systems and ability to produce antimicrobial compounds (hydroxyl fatty acids, organic acids, phenyllactic acid, hydrogen peroxide, bacteriocins, and carbon dioxide) with a broad range of antifungal activity. Hence, LAB can inhibit the growth of mycotoxin-producing fungi, thereby preventing the production of mycotoxins. Fermentation is also an efficient technique for improving nutrient bioavailability and other functional properties of cereal-based products. This review seeks to provide evidence of the potential of LAB from African fermented cereal-based products as potential biological agents against mycotoxin-producing fungi.

A novel electrochemical aptasensor based on layer-by-layer assembly of DNA-Au@Ag conjugates for rapid detection of aflatoxin M1 in milk samples

Aflatoxin M₁ (AFM₁) is a common toxin in dairy products that causes acute and chronic human health disorders. Thus, the development of a rapid and accurate AFM₁ detection method is of vital importance for food safety monitoring. This work was to develop a novel electrochemical aptasensor for sensitive and specific determination of AFM_1. The dendritic-like nanostructure was formed on the gold electrode surface by layer-by-layer assembly of gold-silver core-shell nanoparticles modified with DNA conjugates. In the presence of AFM₁, the specific recognition between AFM₁ and Apt caused the disassociation of the DNA controlled dual Au@Ag conjugates from the surface of the electrode, causing less methylene blue to bind to the surface and weakening the electrochemical signal. The more AFM₁ there is, the weaker the electrochemical signal. Transmission electron microscope results showed that the successfully synthesized Au@Ag nanoparticles exhibited a core-shell structure with Au as core and Ag as shell, and their average diameter was about 30 nm. Under optimal conditions, the electrochemical aptasensor showed a wide detection ranging from 0.05 ng mL^-1 to 200 ng mL^-1, and a low detection limit of 0.02 ng mL^-1. Moreover, the proposed strategy has been successfully applied to the detection of AFM₁ in cow, goat, and sheep milk samples with satisfactory recoveries ranging from 91.10% to 104.05%. This work can provide a novel rapid detection method for AFM₁, and also provide a new sensing platform for the detection of other toxins.

The effect of β-glucan and inulin on the reduction of aflatoxin B1 level and assessment of textural and sensory properties in chicken sausages

In recent years, people have a tendency to consume ready-made foods such as sausages. Therefore, the use of quality raw materials in these products is very important because these compounds may be contaminated with aflatoxin B₁ (AFB₁). Various biological and natural methods have been introduced to reduce aflatoxins in food products. The aim of the present study was to reduce AFB₁ levels. So, β-glucan (βG) and Inulin (IN) were used in different ratios (1: 2%, 2: 1%, 1.5: 1.5%, 0: 3, 3: 0%) in chicken sausages. AFB₁ levels were measured by High Performance Liquid Chromatography (HPLC) in a period of 1–45 days. Then, texture and sensory properties were examined. After 45 days, AFB₁ levels were decreased in all samples, and the highest level of reduction (73.7%) was observed in samples with 5 μg/kg AFB₁ and 3% βG. Texture analysis showed that all the evaluated features complied with the standard. The hardness of chicken sausage with addition of IN (3%) (3.162N) was close to that of the control (2.99N). None of the products were significantly different from the control sample in terms of sensory properties. Therefore, βG and IN are effective in reducing AFB1, and the produced sausages can be acceptable for marketing and be offered for consumption.

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Aflatoxin B₁ levels were assessed by adding β-glucan and inulin.

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Texture and sensory characteristics were investigated.

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Aflatoxin B₁ levels were reduced in all samples.

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The impact of β-glucan on the reduction of aflatoxin B₁ was more than that of inulin.

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The textural and sensory characteristics of the sausage samples were acceptable.

Role of the lactobacilli in food bio-decontamination: Friends with benefits

Food contamination such as toxins and heavy metals has been increasing in the last few decades as a result of industrialization in general and as part of food production in particular. Application of microorganisms in toxins and heavy metals bio-removal has been documented and applied as a favorable decontamination approach due to being environmentally friendly, reasonably simple, and economically feasible. Lactobacilli have been proposed and applied as a beneficial biologic sorbent for toxins and heavy metals in processes of reducing their hazardous bio-availability. The purpose of this review is to summarize the known role of Lactobacillus bacterial species in food bio-decontamination processes. After a quick glimpse of the worthy properties of lactobacilli, their cell wall structure is mentioned. Then the potential role of Lactobacillus strains for mycotoxins (aflatoxins, patulin, ochratoxin A, fumonisins, zearalenone, cyanotoxins, and trichothecenes) and heavy metals (lead, arsenic copper, mercury, cadmium, zinc, aluminum, chromium, and iron) bio-removal were described. In addition, the role of various factors in removal yield and the decontamination mechanism were explained. Finally, the lactobacilli-contaminant stability, in vivo studies, and being a friend or foe of Lactobacillus bacteria are discussed.

Functional yogurt aims to protect against the aflatoxin B1 toxicity in rats

Recently, the rise of mycotoxin contamination in food materials was found to be due to several factors, including climatic changes' impact. Therefore, the aim of this study was to provide a novel food product that allows the reduction of aflatoxin impact in animal tissues. Chicory root-extract (CRE) was evaluated for its active components, antioxidant potency, and antimicrobial activity. The CRE was utilized to produce functional yogurt (FY) that was evaluated in-vivo using experimental rats. The CRE showed high antioxidant activity and recorded valuable content of the active components. Results also showed a high antimicrobial effect against toxigenic fungal strains. The results have reflected the efficiency of the FY to suppress aflatoxin impacts in the animal tissues and biochemical parameters of rats-serum. An enhancement was recorded inliver and kidney functions for rats taking FY with the presence of aflatoxin. It was concluded that consumption of the FY assisted in suppression of the oxidative stress in rats-tissues.

Decontamination of Aflatoxins by Lactic Acid Bacteria

Aflatoxins are toxic secondary metabolic products, which exert great hazards to human and animal health. Decontaminating aflatoxins from food ingredients to a threshold level is a prime concern for avoiding risks to the consumers. Biological decontamination processes of aflatoxins have received widespread attention due to their mild and environmental-friendly nature. Many reports have been published on the decontamination of aflatoxins by microorganisms, especially lactic acid bacteria (LAB), a well-explored probiotic and generally recognized as safe. The present review aims at updating the decontamination of produced aflatoxins using LAB, with an emphasis on the decontamination mechanism and influence factors for decontamination. This comprehensive analysis provides insights into the binding mechanisms between LAB and aflatoxins, facilitating the theoretical and practical application of LAB for decontaminating hazardous substances in food and agriculture.

Preparation of magnetic mesoporous silica from rice husk for aflatoxin B1 removal: Optimum process and adsorption mechanism

The liquid foodstuffs such as edible oil products remain a problem of excessive aflatoxin B1 (AFB1) content. This paper focused on the preparation of magnetic mesoporous silica (MMS) from rice husk ash for the removal of AFB1 in oil system. The MMS preparation process, adsorption conditions, structural characteristics, and adsorption mechanism were investigated. The optimum conditions for MMS preparation were pH 11.0 and 80°C for 24 h. The characterization results showed that magnetic particles were successfully embedded in the MMS and had high responsiveness to a magnetic field, which was advantageous for recyclability. The MMS had ordered uniform channels with a specific surface area of 730.98 m2/g and pore diameter of 2.43 nm. The optimum adsorption conditions were 2 h at 20°C. For AFB1 with an initial concentration of 0.2 μg/mL, the MMS adsorption capacity was 171.98 μg/g and the adsorption rate was 94.59%. The MMS adsorption isotherm fitted the Langmuir model well under the assumption of monolayer AFB1 adsorption with uniformly distributed adsorption sites on the MMS surface. The maximum amount of AFB1 adsorbed according to the Langmuir isotherm was 1118.69 μg/g. A quasi-second-order kinetic model gave a better fit to the process of AFB1 adsorption on MMS. The values of ΔH (-19.17 kJ/mol) and ΔG (-34.09, -34.61, and -35.15 kJ/mol at 283, 293, and 303 K, respectively) were negative, indicating that AFB1 adsorption on MMS was a spontaneous exothermic process. The results indicated that MMS was a promising material for AFB1 removal in oil system, and this study will serve as a guide for practical MMS applications.

Isolation of acid tolerant lactic acid bacteria and evaluation of α-glucosidase inhibitory activity

In this study, lactic acid bacteria strains (LABs) were isolated from Korean traditional fermented food and examined as potential probiotics using in vitro methods. Ten LAB strains survived in de Man, Rogosa and Sharpe broth adjusted to pH 2.5 were tested for resistance to acidic conditions and bile, antimicrobial activity, and α-glucosidase inhibitory activity. Among them, strain MBEL1397 showed antimicrobial activity against Bacillus cereus and exhibited survival rates of over 97% in acidic and bile conditions. The α-glucosidase inhibitory activity was 3.91 ± 0.25%, corresponding to approximately 2.3 times higher than that of acarbose. MBEL1397 was susceptible to ampicillin, erythromycin, and penicillin G and identified as Lactobacillus sakei. It was deposited to Korean Collection for Type Culture (KCTC) as KCTC14037BP. In conclusion, these results demonstrate that L. sakei MBEL1397 might be prominent probiotics with potential hypoglycemic effects.

Characteristics, Occurrence, Detection and Detoxification of Aflatoxins in Foods and Feeds

Mycotoxin contamination continues to be a food safety concern globally, with the most toxic being aflatoxins. On-farm aflatoxins, during food transit or storage, directly or indirectly result in the contamination of foods, which affects the liver, immune system and reproduction after infiltration into human beings and animals. There are numerous reports on aflatoxins focusing on achieving appropriate methods for quantification, precise detection and control in order to ensure consumer safety. In 2012, the International Agency for Research on Cancer (IARC) classified aflatoxins B1, B2, G1, G2, M1 and M2 as group 1 carcinogenic substances, which are a global human health concern. Consequently, this review article addresses aflatoxin chemical properties and biosynthetic processes; aflatoxin contamination in foods and feeds; health effects in human beings and animals due to aflatoxin exposure, as well as aflatoxin detection and detoxification methods.

Lactic Acid Bacteria as Antifungal and Anti-Mycotoxigenic Agents: A Comprehensive Review

Fungal contamination of food and animal feed, especially by mycotoxigenic fungi, is not only a global food quality concern for food manufacturers, but it also poses serious health concerns because of the production of a variety of mycotoxins, some of which present considerable food safety challenges. In today's mega-scale food and feed productions, which involve a number of processing steps and the use of a variety of ingredients, fungal contamination is regarded as unavoidable, even good manufacturing practices are followed. Chemical preservatives, to some extent, are successful in retarding microbial growth and achieving considerably longer shelf-life. However, the increasing demand for clean label products requires manufacturers to find natural alternatives to replace chemically derived ingredients to guarantee the clean label. Lactic acid bacteria (LAB), with the status generally recognized as safe (GRAS), are apprehended as an apt choice to be used as natural preservatives in food and animal feed to control fungal growth and subsequent mycotoxin production. LAB species produce a vast spectrum of antifungal metabolites to inhibit fungal growth; and also have the capacity to adsorb, degrade, or detoxify fungal mycotoxins including ochratoxins, aflatoxins, and Fusarium toxins. The potential of many LAB species to circumvent spoilage associated with fungi has been exploited in a variety of human food and animal feed stuff. This review provides the most recent updates on the ability of LAB to serve as antifungal and anti-mycotoxigenic agents. In addition, some recent trends of the use of LAB as biopreservative agents against fungal growth and mycotoxin production are highlighted.