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Fungal growth inhibition and aflatoxins (AFs) reduction using allyl (AITC), benzyl (BITC) and phenyl (PITC) isothiocyanates were studied in loaf bread contaminated with Aspergillus parasiticus . Two inoculated loaf bread slices were introduced into a plastic tray together with paper filters or small plastic bags paper filters soaked with AITC, BITC or PITC, the final concentration inside the package was of 0.5, 1 or 5 μL/L. The plastic trays, incubated at room temperature, were visual examined for the shelf life evaluation during 8 days. The quantification of the AFs was carried out using liquid chromatography coupled to mass spectrometry (LC-MS/MS). Shelf life increase of three and four days was obtained with small plastic bag paper filter and paper filter soaked with AITC 5 μL/L, respectively. These treatments also showed the highest reductions of AFs. All treatments with small plastic bag paper filter significantly reduced the content of AFs at percentages above 60% except the reduction of AFB 1 in the samples treated with BITC 0.5 μL/L and PITC 1 μL/L. The AFs reduction observed in the packaging with paper filter were above 60% only using AITC at the concentrations of 1 and 5 μL/L.

Food spoilage caused by mycotoxigenic fungi represents an important food safety problem. Lactic acid bacteria (LAB) are used as starter cultures in a larger number of food products. In this study, 16 strains of LAB were cultivated in MRS broth under anaerobiosis. Then, cell free supernatants were obtained by centrifugation and their antifungal activity against Aspergillus parasiticus and Penicillium expansum was tested using the disc-diffusion method. Furthermore, the LABs that showed in vitro antifungal activity were used in bread fermentation with yeast in order to study fungal growth inhibition and aflatoxin (AF) reduction in processed bread previously inoculated with A. parasiticus. The compounds present in the fermented medium of six LAB strains induced inhibition of P. expansum growth, whereas five probiotic strains produced antifungal compounds against A. parasiticus. The analysis by liquid chromatography coupled to mass spectrometry in tandem showed a reduction of the AF content in bread samples fermented with yeast and LABs. The reduction of AFs ranged from 84.1 to 99.9%. Moreover, bread sample studies showed a shelf life increase of about 3–4 days.

Patulin (PAT) is a toxic fungal metabolite produced by Penicillium, Aspergillus and Byssochlamys growing especially in fruit and cereals. PAT exhibits a number of toxic effects in animals and its presence in food is undesirable. In this study the reduction of the mycotoxin PAT produced by a strain of Penicillium expansum, on wheat tortillas was studied using volatile bioactive compounds present in the oriental and yellow mustard flour and also using the standard solution of the antifungal compound allyl isothiocyanate (AIT), developing an active packaging with two different systems of release of those bioactive compounds. Also the kinetic of volatilization of the compounds used in the bioactive packaging was evaluated using the technique of the gas chromatography (GC) coupled to the flame ionization detector (FID). The PAT was extracted from the samples using the QUECHERS methodology and was determined using the technique of the liquid chromatography (LC) coupled to the mass spectrometry detector in tandem (MS/MS). The maximum of volatilization of the AIT in the bioactive packaging is produced between 1 and 24 h depending on the volatilization technique and is stable during two months, whereas the reduction of PAT evidenced in the samples treated ranged from 80 to 100%.

Aflatoxins (AFs) are produced mainly by the molds Aspergillus flavus and Aspergillus parasiticus. Aflatoxin B1 (AFB1) is classified as carcinogenic to humans. The aim of this study was to evaluate the capacity of different strains of Lactobacilli (Lb.) and Bifidobacteria (Bf.) to reduce the bioaccessibility of AFB1 and aflatoxin B2 (AFB2), spiked in loaf bread, using a dynamic in vitro simulated gastrointestinal digestion system. Aliquots of 20 mL of gastric and duodenal fluids were sampled for the determination of the mycotoxins gastric and duodenal bioaccessibility respectively, by liquid-chromatography coupled to the mass spectrometry in tandem (LC–MS/MS). A reduction of AFs bioaccessibility compared to the control (digestion without bacterial strains) was evidenced. The strains that evidenced the highest gastric and duodenal bioaccessibility reductions of AFB1 and AFB2 were Lb. johnsoni CECT 289, Lb. reuteri CECT 725, Lb. plantarum CECT 220 and Lb. casei CECT 4180, with values ranging from 76.38 to 98.34% for AFB1 and from 77.14 to 98.66% for AFB2. These results suggest that a food enriched with specific probiotic microorganisms and consumed at the same time as food contaminated with AFs, could reduce the risk associated to the intake of these toxic compounds contained in food.

Fungal growth inhibition and aflatoxins (AFs) reduction using allyl (AITC), benzyl (BITC) and phenyl (PITC) isothiocyanates were studied in loaf bread contaminated with Aspergillus parasiticus. Two inoculated loaf bread slices were introduced into a plastic tray together with paper filters or small plastic bags paper filters soaked with AITC, BITC or PITC, the final concentration inside the package was of 0.5, 1 or 5μL/L. The plastic trays, incubated at room temperature, were visual examined for the shelf life evaluation during 8 days. The quantification of the AFs was carried out using liquid chromatography coupled to mass spectrometry (LC-MS/MS). Shelf life increase of three and four days was obtained with small plastic bag paper filter and paper filter soaked with AITC 5μL/L, respectively. These treatments also showed the highest reductions of AFs. All treatments with small plastic bag paper filter significantly reduced the content of AFs at percentages above 60% except the reduction of AFB1 in the samples treated with BITC 0.5μL/L and PITC 1μL/L. The AFs reduction observed in the packaging with paper filter were above 60% only using AITC at the concentrations of 1 and 5μL/L.

Humans can be exposed to cyanotoxins through the ingestion of contaminated water, food or beverages. In the present work, the bioaccesibility of Cylindrospermopsin (CYN), one of the most relevant cyanotoxins, was evaluated in a pure CYN solution and cooked CYN-contaminated fish muscles (20 μg/mL). An in vitro digestion model including the salivar, gastric, duodenal and colonic phases was performed, being each fraction analyzed by HPLC-MS-MS to evaluate CYN degradation. Moreover, Caco-2/TC7 cells were exposed to the digested duodenal and colonic phases to elucidate the final bioavailability of CYN in an approximation to the real human exposure scenario. The results revealed that CYN bioaccesibility decreased after the digestive process in all the cooked fish samples. The most drastic reductions were observed after lactic acid bacteria exposure. Thus, the highest bioaccesibility values were obtained in fish cooked by steaming (12.5%) and broiling (10.9%) meanwhile CYN was not detected in the colonic phase after boiling and microwaving. Regarding the duodenal and colonic availability, only in CYN pure digested solution the cyanotoxin was identified. The results obtained showed that digestion processes plays a very important role in the degradation of CYN, which should be considered when preparing a risk assessment of CYN.

Emerging Fusarium mycotoxins include the toxic secondary metabolites fusaproliferin, enniatins, beauvericin (BEA), and moniliform. BEA is produced by some entomo- and phytopathogenic Fusarium species and occurs naturally on corn and corn-based foods and feeds infected by Fusarium spp. BEA has shown various biological activities (antibacterial, antifungal, and insecticidal) and possesses toxic activity, including the induction of apoptosis, increase cytoplasmic calcium concentration and lead to DNA fragmentation in mammalian cell lines. Cereals food processing has an important effect on mycotoxin stability, leading to less-contaminated food compared to the raw materials. Different industrial processes have shown to be effective practices to reduce BEA contents due to thermal food processing applied, such as cooking, boiling, baking, frying, roasting and pasteurization. Some studies demonstrated the capacity of lactic acid bacteria to reduce the presence of the BEA in model solution and in food chain through fermentation processes, modifying this mycotoxin in a less toxic derivate. Prebiotic and probiotic ingredient can modulate the bioaccessibility of BEA reducing the risk of intake of this minor Fusarium mycotoxin. This review summarizes the existing data on occurrence, toxicity and especially on BEA reduction strategies in food and feed such as chemical reduction, biocontrol and food processing.

Food spoilage caused by mycotoxigenic moulds represents an important problem in food security. The antimicrobial peptides are compounds of natural origin constituted by a variable number (5–100) of amino acids held together through peptide bonds. In this work, the cell free supernatants (CFSs) containing peptides obtained from four strains of LAB were lyophilized, filtered and tested to determine the antifungal activity against Aspergillus Parasiticus and Penicillium expansum . CFS obtained by Lactobacillus plantarum showed the highest inhibition activity. CFS was fractionated by size exclusion chromatography and injected into the liquid chromatography coupled to diode array detector. One of the recollected fractions resulted interesting for the presence of three peaks that were purified by the technique of the LC-DAD using a semi preparative C18 column. Finally, the antifungal activity of the purified peptides was studied against A. Parasiticus and P. expansum in liquid medium. The MALDI-TOF/TOF mass spectrometry was used for the peptides identification. The three purified peptides presented an amino acidic sequence identified by a bioinformatics program of SGADTTFLTK, LVGKKVQTF, and GTLIGQDYK. The first peptide purified reduced 58% and 73% the growth of P. expansum and A. parasiticus , respectively, in liquid medium after 48 h incubation.

Mycotoxins are toxic metabolites produced by filamentous fungi, as Aspergillus, Penicillium and Fusarium. The first objective of this research was to study the presence of mycotoxins in 60 samples of refrigerated pizza dough, by extraction with methanol and determination by liquid chromatography associated with tandem mass spectrometry (LC-MS/MS). Then, the estimated dietary intakes (EDIs) of these mycotoxins, among the Spanish population, was calculated and the health risk assessment was performed, comparing the EDIs data with the tolerable daily intake values (TDIs). The mycotoxins detected in the analyzed samples were aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), zearalenone (ZEA), enniatin A (ENA), enniatin A1 (ENA1), enniatin (ENB), enniatin B1 (ENB1) and BEA (beauvericin) with average concentration of the positive samples of 4.09 μg/kg, 0.50 μg/kg, 0.79 μg/kg, 77.78 μg/kg, 14.96 μg/kg, 4.54 μg/kg, 3.37 μg/kg, 1.69 μg/kg and 22.39 μg/kg, respectively. The presence of ZEA, ENA1, ENB and ENB1 was detected in 100% of the samples, AFB2 in 32%, AFB1 in 23%, ENA in 8% and BEA in 3%. Twelve percent of the samples contaminated with AFB1 and 12% of the doughs contaminated with ZEA exceeded the EU legislated maximum limits. The dietary intakes were estimated considering three different age groups of population, and the EDIs calculated for the mycotoxins detected in the samples were all below the established TDI.

BACKGROUND Brazil produces approximately 40 000 tons of Brazil nuts annually, which is commonly contaminated with fungi and mycotoxins. Gaseous allyl isothiocyanate (AITC) was used to inhibit the growth of Aspergillus parasiticus and its production of aflatoxins (AFs) in Brazil nuts. RESULTS Nuts were inoculated with 104 spores g−1 of A. parasiticus and placed in airtight glass jars with controlled relative humidity (RH = 95 or 85%). Samples were treated with 0, 0.5, 1.0 or 2.5 µL L−1 of gaseous AITC and analyzed after 30 days to determine the fungal population and AFs content. Samples were also submitted to sensory evaluation. AITC at 2.5 µL L−1 could completely inhibit the fungal growth and AFs production in both the RH tested. AITC at 0.5 and 1 µL L−1 did not affect the microbial growth at RH = 95%, but 1 µL L−1 reduced the production of AFs by ∼50%. All AITC treatments reduced the fungal population and AFs to undetectable levels at RH = 85%. None of the concentrations altered sensory characteristics of Brazil nuts. CONCLUSION Gaseous AITC could be used as an alternative to inhibit the growth of A. parasiticus during storage and transport of Brazil nuts. © 2017 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

This study investigates the reduction of zearalenone (ZEA) and α-zearalenol (α-ZOL) on a solution model using allyl isothiocyanate (AITC) and also determines the bioaccessibility and bioavailability of the reaction products isolated and identified by MS-LIT. Mycotoxin reductions were dose-dependent, and ZEA levels decreased more than α-ZOL, ranging from 0.2 to 96.9% and 0 to 89.5% respectively, with no difference (p⩽0.05) between pH 4 and 7. Overall, simulated gastric bioaccessibility was higher than duodenal bioaccessibility for both mycotoxins and mycotoxin-AITC conjugates, with duodenal fractions representing ⩾63.5% of the original concentration. Simulated bioavailability of reaction products (α-ZOL/ZEA-AITC) were lower than 42.13%, but significantly higher than the original mycotoxins. The cytotoxicity of α-ZOL and ZEA in Caco-2/TC7 cells was also evaluated, with toxic effects observed at higher levels than 75μM. Further studies should be performed to evaluate the toxicity and estrogenic effect of α-ZOL/ZEA-AITC.

ɛ‐Poly‐l‐lysine (ɛ‐PL) is a cationic peptide with a broad‐spectrum antimicrobial activity. This study investigates the use of ɛ‐PL as natural antimicrobial to inhibit fungal growth and to reduce aflatoxins (AFs) production. Antifungal activity of starch biofilms with different concentrations of ɛ‐Poly‐l‐lysine (ɛ‐PL) was determined in solid medium against Aspergillus parasiticus (AFs producer) and Penicillium expansum. Then, biofilms were tested as antimicrobial devices for the preservation of bread loaf inoculated with A. parasiticus CECT 2681 and P. expansum CECT 2278. Shelf life and AFs content were examined. Biofilms with concentrations of ɛ‐PL less than 1.6 mg/cm2 showed no fungal growth inhibition in solid medium, while the antifungal activity of the films with greater than 1.6 mg/cm2 of ɛ‐PL was dose dependent. The shelf life of bread inoculated with A. parasiticus was increased by 1 day with the use of films containing 1.6–6.5 mg ɛ‐PL/cm2, while shelf life of bread tainted with P. expansum was increased by 3 day with 6.5 mg ɛ‐PL/cm2. AFs production was greatly inhibited by ɛ‐PL biofilms (93–100%). Thus, ɛ‐PL biofilms could be potentially used as antimicrobial device during bread storage as a natural alternative to the synthetic preservatives. Practical applications Ɛ‐Polylysin is a natural substance from microbial metabolism. Polylysine has a function to prevent a microbe from proliferating by ionic adsorption in the microbe. ɛ‐polylysine has a wide antibacterial spectrum and has an obvious lethal effect on Gram‐positive and Gram‐negative bacteria, yeast, mold, viruses, etc. It has a good antibacterial effect on the Gram‐negative bacteria E. coli and Salmonellae, which are difficult to control with other natural preservatives. ɛ‐Polylysine has already been used generally as a food additive in Japan, Korea and other part of world. In the United States, FDA has recognized the polylysine as a GRAS material. Considered the positive results obtained in the study, this compound could be used for the production of antimicrobial biofilms, applied as separator slices in the loaf bread production, to prevent the growth of the mycotoxigenic fungi A. parasiticus and P. expansum, contributing to reduce the use of the synthetically preservatives in bakery industry and also of the negative impact that these compounds could generate on the health of the end users.