0000000000203979

AUTHOR

Tiago De Melo Nazareth

Antifungal activity of natamycin and development of an edible film based on hydroxyethylcellulose to avoid Penicillium spp. growth on low-moisture mozzarella cheese

Abstract This study aimed to investigate natamycin's in vitro antifungal activity against Penicillium strains and determine its antifungal effect on Mozzarella cheese slices contaminated with P. commune. Besides, the residual content of natamycin in the samples was assessed during the storage. Natamycin was either sprayed on the cheese surface or incorporated into an edible hydroxyethylcellulose film at concentrations of 0, 0.25, 0.5, and 1 mg/dm2. Natamycin showed an antifungal effect against all Penicillium strains with MIC values ranging from 1.6 to 3.1 μg/mL and MFC values ranging from 12.5 to 200.0 μg/mL. Moreover, both applied techniques significantly (p ≤ 0.05) reduced the population…

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Evaluation of gaseous allyl isothiocyanate against the growth of mycotoxigenic fungi and mycotoxin production in corn stored for 6 months

Brazil produces approximately 63 million tons of corn kernels annually, which is commonly contaminated with fungi and mycotoxins. The objective of this study was to evaluate the efficacy of gaseous allyl isothiocyanate (AITC) to inhibit the growth of Aspergillus parasiticus and Fusarium verticillioides, and mycotoxin production (aflatoxins B1 , B2 , G1 and G2 , fumonisins B1 and B2 ) in corn during 180 days of storage.; Results: AITC at 50 µL L-1 resulted in a significant reduction of the fungal population (P < 0.05) after 180 days, decreasing 3.17 log(CFU g-1 ) and 3.9 log(CFU g-1 ) of A. parasiticus and F. verticillioides respectively in comparison with the control. In addition, 10 and 50…

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Antifungal activity of peracetic acid against toxigenic fungal contaminants of maize and barley at the postharvest stage

Contamination of maize and barley grain during storage by the toxigenic fungi Aspergillus flavus (A. flavus) and Penicillium Verrucosum (P. verrucosum) is both an economic and a public health problem, especially in less industrialized countries. Peracetic acid (PA) is a compound used for the disinfection of food and food contact surfaces. Unlike other disinfectants, it leaves no toxic residues and its decomposition products (CH3COOH, O2 nd H2O) are environmentally friendly. In order to apply PA to preserve maize and barley grain during storage, first, the Minimum Inhibitory Concentration (MIC) and Minimum Fungicidal Concentration (MFC) against both fungi were determined in a 96-well sterile…

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Development of an Antifungal and Antimycotoxigenic Device Containing Allyl Isothiocyanate for Silo Fumigation

The aims of this study were to evaluate the antifungal activity of the bioactive compound allyl isothiocyanate (AITC) against Aspergillus flavus (8111 ISPA) aflatoxins (AFs) producer and Penicillium verrucosum (D-01847 VTT) ochratoxin A (OTA) producer on corn, barley, and wheat. The experiments were carried out initially in a simulated silo system for laboratory scale composed of glass jars (1 L). Barley and wheat were contaminated with P. verrucosum and corn with A. flavus. The cereals were treated with a hydroxyethylcellulose gel disk to which 500 &micro

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Application of White Mustard Bran and Flour on Bread as Natural Preservative Agents.

In this study, the antifungal activity of white mustard bran (MB), a by-product of mustard (Sinapis alba) milling, and white mustard seed flour (MF) was tested against mycotoxigenic fungi in the agar diffusion method. The results obtained were posteriorly confirmed in a quantitative test, determining the minimum concentration of extract that inhibits the fungal growth (MIC) and the minimum concentration with fungicidal activity (MFC). Since MF demonstrated no antifungal activity, the MB was stored under different temperature conditions and storage time to determine its antifungal stability. Finally, an in situ assay was carried out, applying the MB as a natural ingredient into the dough to …

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Development of a Bioactive Sauce Based on Oriental Mustard Flour with Antifungal Properties for Pita Bread Shelf Life Improvement

Ochratoxin A (OTA) is a mycotoxin produced in the secondary metabolism of fungus belonging to the genus Aspergillus and Penicillium. In this study, the employment of oriental mustard flour (OMF) as an ingredient in a packaged sauce was evaluated for the generation in situ of the antimicrobial compound allyl isothiocyanate (AITC) in order to preserve pita bread contaminated with Penicillium verrucosum VTT D-01847, an OTA producer, in an active packaging system. Four different concentrations (8, 16, 33 and 50 mg/g) were tested. Mycelium formation, mycotoxin production, AITC absorbed by the food matrix, and volatilization kinetics were studied for each concentration. The results obtained were …

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Potential Application of Lactic Acid Bacteria to Reduce Aflatoxin B1 and Fumonisin B1 Occurrence on Corn Kernels and Corn Ears

Fungal spoilage is an important issue for the food industry, leading to food sensory defects, food waste, economic losses and public health concern through the production of mycotoxins. Concomitantly, the search for safer natural products has gained importance since consumers began to look for less processed and chemically treated foods. In this context, the aim of this study was to evaluate the antifungal and antimycotoxigenic effect of seven strains of Lactobacillus plantarum. Lactic acid bacteria (LAB) were grown on Man Rogosa Sharpe (MRS) broth at 37 &ordm

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Antifungal activity of peracetic acid against toxigenic fungal contaminants of maize and barley at the postharvest stage

Abstract Contamination of maize and barley grain during storage by the toxigenic fungi Aspergillus flavus (A. flavus) and Penicillium Verrucosum (P. verrucosum) is both an economic and a public health problem, especially in less industrialized countries. Peracetic acid (PA) is a compound used for the disinfection of food and food contact surfaces. Unlike other disinfectants, it leaves no toxic residues and its decomposition products (CH3COOH, O2 and H2O) are environmentally friendly. In order to apply PA to preserve maize and barley grain during storage, first, the Minimum Inhibitory Concentration (MIC) and Minimum Fungicidal Concentration (MFC) against both fungi were determined in a 96-we…

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Antifungal and antimycotoxigenic activity of allyl isothiocyanate on barley under different storage conditions

Abstract The present study evaluated the efficacy of allyl isothiocyanate (AITC) in avoiding the growth of Penicillium verrucosum and consequent ochratoxin A (OTA) production in barley during storage for 90 d. Environmental humidity was controlled using saturated salt solutions and moisture content (MC) of the grain was analyzed. Moreover, the residual concentration of AITC on stored barley was also examined. Samples with 20.6% of MC presented the highest absorption of AITC with levels ranging from 75 to 4 mg/kg at day 1 and 90, respectively. The population of P. verrucosum was significantly reduced after 24 h of AITC exposure. After 90 d, the non-treated control group reached a fungal popu…

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Gaseous allyl isothiocyanate to inhibit the production of aflatoxins, beauvericin and enniatins by Aspergillus parasiticus and Fusarium poae in wheat flour

Abstract There is a growing concern about the presence of mycotoxins in foods, since up to 25% of cereals and cereal foods are contaminated with these compounds. Moreover, the general public is against the use of synthetic preservatives in foods and the use of natural antimicrobials in foods is a current trend. Allyl isothiocyanate (AITC) is a volatile antimicrobial derived from oriental and black mustard. The objective of this work was to evaluate the capacity of gaseous AITC in inhibiting the production of mycotoxins by Aspergillus parasiticus (aflatoxin producer) and Fusarium poae (beauvercin and enniatin producer) in wheat flour. Petri dish lids filled with 2 g of wheat flour were inocu…

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Assessment of allyl isothiocyanate as a fumigant to avoid mycotoxin production during corn storage

The occurrence of fungi and mycotoxins in foods modify sensorial properties and represents a health risk for consumers, and the use of natural antimicrobials may be an alternative to reduce this problem. The objective of this study was evaluate the potential of allyl isothiocyanate (AITC) in inhibit the production of mycotoxins in corn kernels by Aspergillus parasticus, Fusarium tricinctum, Fusarium verticillioides, Alternaria alternata and Gibberela zeae. Kernels were treated with gaseous AITC at 50, 100 or 500 &mu;L/L during 48 h in hermetic flasks. Then, flasks were opened for 24 h and 100 g of corn were inoculated with 105 conidia/g of either fungal species. Flasks were kept at 23 &deg;…

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Fundamentals on the Molecular Mechanism of Action of Antimicrobial Peptides

Abstract Antimicrobial peptides (AMPs) are produced by several organisms as their first line of defense. Constituted by amino acids, they may present different mechanisms of action. The antimicrobial activity can be used by the peptide-producing organism itself, as innate immune strategy, or in the industry, applying as natural source preservatives. Understanding the possibilities of the operation of these compounds is a prerequisite for the development of effective uses, as well as for the establishment of combinations, which can even expand their applications considering the possibilities of genetic manipulations. Thus, the objective of this article is to review the basic principles of AM…

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Effect of allyl isothiocyanate on transcriptional profile, aflatoxin synthesis, and Aspergillus flavus growth.

Abstract The goals of this study were to determine the efficacy of allyl isothiocyanate (AITC) against the growth of A. flavus and Aflatoxin B1 (AFB1) production as well as to evaluate changes in the transcriptome profile when colonizing maize. A. flavus was inoculated in potato dextrose agar (PDA), the plates were placed inside glass jars and the mycelial growth (MG) was monitored for 7 d. Likewise, maize grains were contaminated with A. flavus in glass jars of 1 L and treated with 0.125, 0.25, 0.5, 1 and 5 µL of AITC. The moisture content (MC) of grains was 15 and 21%. After 7 days of storage, the MG was significantly reduced in doses higher than 0.125 µL/L of AITC. All doses of AITC redu…

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