A Novel Niosome-Encapsulated Essential Oil Formulation to Prevent Aspergillus flavus Growth and Aflatoxin Contamination of Maize Grains During Storage

Aflatoxin (AF) contamination of maize is a major concern for food safety. The use of chemical fungicides is controversial, and it is necessary to develop new effective methods to control Aspergillus flavus growth and, therefore, to avoid the presence of AFs in grains. In this work, we tested in vitro the effect of six essential oils (EOs) extracted from aromatic plants. We selected those from Satureja montana and Origanum virens because they show high levels of antifungal and antitoxigenic activity at low concentrations against A. flavus. EOs are highly volatile compounds and we have developed a new niosome-based encapsulation method to extend their shelf life and activity. These new formulations have been successfully applied to reduce fungal growth and AF accumulation in maize grains in a small-scale test, as well as placing the maize into polypropylene woven bags to simulate common storage conditions. In this latter case, the antifungal properties lasted up to 75 days after the first application.

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In Vitro Activity of Balanites aegyptiaca and Tamarindus indica Fruit Extracts on Growth and Aflatoxigenicity of Aspergillus flavus and A. parasiticus

Journal of Food Research ◽

10.5539/jfr.v2n4p68 ◽

2013 ◽

Vol 2 (4) ◽

pp. 68 ◽

Cited By ~ 1

Author(s):

Saifeldin Ahmed El-nagerabi ◽

Abdulkadir E. Elshafie ◽

Mohamed R. Elamin

Keyword(s):

Aspergillus Flavus ◽

Fungal Growth ◽

Aflatoxin Contamination ◽

Tamarindus Indica ◽

Balanites Aegyptiaca ◽

Total Aflatoxin ◽

Animal Products ◽

Fruit Extracts ◽

Aflatoxin B

Aflatoxin and especially aflatoxin B1 (AFB1) is a carcinogenic secondary metabolite synthesized by certain Aspergillus species. They contaminate natural and processed agricultural and animal products which render them unfit for consumption. The aim of this study was to evaluate the in vitro effects of Balanites aegyptiaca and Tamarindus indica fruit extracts on the growth and aflatoxin secretion of Aspergillus flavus (SQU21) and A. parasiticus (CBS921.7) strains. The two fruit extracts significantly (P < 0.05) reduced aflatoxin and did not inhibit mycelial dry weights of the two Aspergillus strains. At different concentrations of balanites (2.5-10%), the inhibition of total aflatoxin was 49.9-84.8% for A. flavus (SQU21) and 32.1-84.4% for A. parasiticus (CBS921.7), whereas the inhibition of aflatoxin Bwas 38.2-81.4% and 32.8-80.6% for the two strains. Tamarind fruit extract (2.5-7.5%) caused 28.8-84.2% and 40.7-85.5% reductions in total aflatoxin and 37.1-83.5% and 33.9-85.9% in aflatoxin B for the two strains, respectively. None of these extracts inhibited the fungal growth or detoxified synthetic aflatoxin B1. We have concluded that these fruits contain various inhibitors to aflatoxin biosynthesis and secretion. Therefore, they can be used in combination as safe green biopreservatives to combat aflatoxin contamination of food.

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Antifungal Activity and Detoxification of Aflatoxins by Plant Extracts: Potential for Food Applications

The Open Food Science Journal ◽

10.2174/1874256401810010024 ◽

2018 ◽

Vol 10 (1) ◽

pp. 24-32 ◽

Cited By ~ 3

Author(s):

Bárbara Ponzilacqua ◽

Carlos Humberto Corassin ◽

Carlos Augusto Fernandes Oliveira

Keyword(s):

Antifungal Activity ◽

Essential Oils ◽

Plant Extracts ◽

Fungal Growth ◽

Aflatoxin Contamination ◽

Attractive Alternative ◽

Low Concentrations ◽

Food Applications ◽

Aflatoxin B

Aflatoxins are secondary metabolites produced by fungi of the genusAspergillus, which occur naturally in cereals like corn, beans and rice. Aflatoxin B1causes an extensive number of toxic effects in animals and humans. This mycotoxin is a stable term and can act in low concentrations due to their higher toxicity. Management to prevent commodities aflatoxin contamination is essential during the production, mainly in pre- and post-harvest steps. A number of essential oils and aqueous plant extracts have been reported to be fungal growth inhibitors and may provide an attractive alternative to prevent aflatoxin contamination in foods. Thus, the aim of this review is to highlight recent data on thein vitroantifungal activity of essential oils and aqueous extracts from plants and discuss the perspectives of their use in food products.

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A Phytoalexin and Aflatoxin Producing Peanut Seed Culture System

Peanut Science ◽

10.3146/i0095-3679-21-2-13 ◽

1994 ◽

Vol 21 (2) ◽

pp. 130-134 ◽

Cited By ~ 6

Author(s):

S. M. Basha ◽

R. J. Cole ◽

S. K. Pancholy

Keyword(s):

Water Stress ◽

Culture System ◽

Fungal Growth ◽

Aflatoxin Contamination ◽

Peanut Seed ◽

Seed Culture ◽

Murashige And Skoog Medium ◽

Yellow Orange ◽

Increased Susceptibility

Abstract An in vitro seed culture system was established to grow peanut seed of different maturities viz. white, yellow, orange, brown and black, using a modified Murashige and Skoog medium. Under this system peanut seed of yellow, orange, brown and black maturity categories grew to maturity as measured by increase in their size and germinability. In vitro cultured seeds produced significant amounts of phytoalexins and were contaminated with aflatoxins following their inoculation with Aspergillus spp. while the noninoculated sterile controls did not produce any phytoalexins. Exposure of seed cultures to water stress using various concentrations of mannitol (0 to 1 M) and polyethylene glycol 8000 (0-30% w/v) caused a significant decrease in their phytoalexin producing ability, and enhanced fungal growth compared to the nonstressed controls. The seeds that were stressed with mannitol and subsequently inoculated with A. flavus and A. parasiticus showed a significant increase in the aflatoxin contamination of stressed seed compared to the unstressed control. This would indicate that in vitro grown seeds responded to water stress similar to the field grown peanuts by loosing their ability to produce phytoalexins and increased susceptibility to aflatoxin contamination. Hence, this system has a potential application in evaluating peanut genotypes for aflatoxin resistance under water stress.

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A Caleosin-Like Protein with Peroxygenase Activity Mediates Aspergillus flavus Development, Aflatoxin Accumulation, and Seed Infection

Applied and Environmental Microbiology ◽

10.1128/aem.00867-15 ◽

2015 ◽

Vol 81 (18) ◽

pp. 6129-6144 ◽

Cited By ~ 14

Author(s):

Abdulsamie Hanano ◽

Ibrahem Almousally ◽

Mouhnad Shaban ◽

Elizabeth Blee

Keyword(s):

Fatty Acid ◽

Aspergillus Flavus ◽

Polyunsaturated Fatty Acid ◽

Calcium Binding ◽

Antioxidant Activities ◽

Fungal Growth ◽

Oxidation Reactions ◽

Content Type ◽

Fatty Acid Hydroperoxides

ABSTRACTCaleosins are a small family of calcium-binding proteins endowed with peroxygenase activity in plants. Caleosin-like genes are present in fungi; however, their functions have not been reported yet. In this work, we identify a plant caleosin-like protein inAspergillus flavusthat is highly expressed during the early stages of spore germination. A recombinant purified 32-kDa caleosin-like protein supported peroxygenase activities, including co-oxidation reactions and reduction of polyunsaturated fatty acid hydroperoxides. Deletion of the caleosin gene prevented fungal development. Alternatively, silencing of the gene led to the increased accumulation of endogenous polyunsaturated fatty acid hydroperoxides and antioxidant activities but to a reduction of fungal growth and conidium formation. Two key genes of the aflatoxin biosynthesis pathway,aflRandaflD, were downregulated in the strains in whichA. flavusPXG(AfPXG) was silenced, leading to reduced aflatoxin B1 productionin vitro. Application of caleosin/peroxygenase-derived oxylipins restored the wild-type phenotype in the strains in whichAfPXGwas silenced.PXG-deficientA. flavusstrains were severely compromised in their capacity to infect maize seeds and to produce aflatoxin. Our results uncover a new branch of the fungal oxylipin pathway and may lead to the development of novel targets for controlling fungal disease.

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Combinational inhibitory action of essential oils and gamma irradiation for controlling Aspergillus flavus and Aspergillus parasiticus growth and their aflatoxins biosynthesis in vitro and in situ conditions

Food Science and Technology International ◽

10.1177/10820132211053086 ◽

2021 ◽

pp. 108201322110530

Author(s):

Hanan H Abdel-Khalek ◽

Ali AI Hammad ◽

Reham MMA El-Kader ◽

Khayria A Youssef ◽

Dalia AM Abdou

Keyword(s):

Essential Oils ◽

Aspergillus Flavus ◽

Aspergillus Parasiticus ◽

Fungal Growth ◽

Storage Period ◽

Complete Removal ◽

Γ Irradiation ◽

Star Anise ◽

In Situ Conditions

The purpose of this study was to investigate the effects of certain essential oils (star anise, lemon leaves, marjoram, fennel, and lavender) on the fungal growth of Aspergillus flavus and Aspergillus parasiticus and their production of aflatoxin B1 (AFB1). The degree of suppression of the aflatoxigenic strains’ growth and their production of AFB1 is mainly affected by the kind and the concentration of the tested essential oils (EOs). Star anise essential oil had the lowest minimum inhibitory concentration (0.5 and 1.0 μL/mL) against A. flavus and A. parasiticus, respectively, so it was the best among the five different oils. The study of liquid chromatography with tandem mass spectrometry revealed that star anise EO resulted in a 98% reduction in AFB1 without a breakdown of AFB1 products after treatment thus the complete removal of AFB1 was done without any toxic residues. The combination showed a synergistic effect, the combinational treatment between γ-irradiation at a low dose (2 kGy) and star anise EO at concentrate 0.5 μL/g destroyed A. flavus and A. parasiticus inoculated (individually) in sorghum and peanut, respectively throughout the storage period (8 weeks).

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An evaluation of potential seed treatments to control Fusarium solani f.sp. phaseoli, the cause of foot and root rot of Phaseolus vulgaris

The Journal of Agricultural Science ◽

10.1017/s0021859600027428 ◽

1977 ◽

Vol 89 (1) ◽

pp. 235-238 ◽

Cited By ~ 5

Author(s):

P. E. Russell ◽

A. E. A. Mussa

Keyword(s):

Phaseolus Vulgaris ◽

Fusarium Solani ◽

Root Rot ◽

Similar Pattern ◽

Fungal Growth ◽

Systemic Fungicide ◽

Product Concentration ◽

Low Concentrations ◽

High Concentrations

SummaryTwo systemic fungicides, benomyl and thiabendazole, were more active than the non-systemic fungicide Drazoxolon in inhibiting fungal growth in vitro. A similar pattern was obtained in glasshouse trials with benomyl and thiabendazole giving adequate protection at low concentrations while Drazoxolon was ineffective unless applied at 50% the commercial product concentration. A field trial using thiabendazole, Drazoxolon and a mixture of benomyl and thiram confirmed the glasshouse results.Some phytotoxicity was noticed with high concentrations of both benomyl and thiabendazole, but satisfactory disease control was achieved using fungicide concentrations which did not induce phytotoxicity.

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Abiotic factors affect growth and aflatoxin B1 production by Aspergillus flavus strains on chilli powder and red chillies

World Mycotoxin Journal ◽

10.3920/wmj2021.2715 ◽

2021 ◽

pp. 1-10

Author(s):

D. Al-Jaza ◽

A. Medina ◽

N. Magan

Keyword(s):

Aspergillus Flavus ◽

Statistical Difference ◽

Abiotic Factors ◽

Significant Risk ◽

Optimal Growth ◽

Toxin Production ◽

Storage Conditions ◽

Contour Maps ◽

Lag Phases

Chillies and chilli-based products are important spices on a global basis. The production, processing, transport and storage phases of chillies are prone to infection by Aspergillus Section Flavi and contamination with aflatoxins (AFs), especially aflatoxin B1 (AFB1) for which legislative limits exist in many countries. We have examined the effect of the interacting abiotic factors of water availability (water activity, aw; 0.995-0.850 aw) and temperature (15-37 °C) on (a) lag phases prior to growth, (b) growth, (c) AFB1 production and (d) contour maps of optimum and boundary conditions for colonisation and toxin production by three Aspergillus flavus strains on a 10% chilli-based medium. Additional studies with whole red chillies + A. flavus conidial inoculum on AFB1 contamination during storage for 10-20 days at 30 °C were also carried out. In vitro, the lag phases before growth were delayed by lower temperatures (15, 20 °C) and aw levels (0.928-0.901 aw). There was no statistical difference in growth between the three strains. Optimal growth was at 37 °C and 0.982 aw with no growth at 0.85 aw. Optimal temperature × aw conditions for AFB1 production were at 30 °C and 0.982 aw with no statistical difference in production between strains. No AFB1 was produced at 15-20 °C at 0.901 and 0.928 aw levels, respectively. In situ studies with A. flavus inoculated whole red chillies at 0.90 and 0.95 aw found that this species became the major component of the total fungal populations at 30 °C after 10-20 days storage. AFB1 contamination was above the European legislative limits (5 μg/kg) for spices at 0.90 aw after 20 days storage and at 0.95 aw after 10 and 20 days. This suggests that storage conditions of ≥0.90 aw, especially at ≥25-30 °C represents a significant risk of contamination with AFB1 at levels where rejection might occur, even after only 10-20 days storage.

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No Effect of Soybean Lipoxygenase on Aflatoxin Production in Aspergillus flavus–Inoculated Seeds

Journal of Food Protection ◽

10.4315/0362-028x-65.12.1984 ◽

2002 ◽

Vol 65 (12) ◽

pp. 1984-1987 ◽

Cited By ~ 6

Author(s):

J. E. MELLON ◽

P. J. COTTY

Keyword(s):

Aspergillus Flavus ◽

Fungal Pathogens ◽

Seed Viability ◽

Soybean Seed ◽

Fungal Growth ◽

Aflatoxin Production ◽

Aflatoxin Contamination ◽

Soybean Seeds ◽

Heat Treated ◽

Significant Difference

Soybean lines lacking lipoxygenase (LOX) activity were compared with soybean lines having LOX activity for the ability to support growth and aflatoxin B1 production by the fungal seed pathogen Aspergillus flavus. Whole seeds, broken seeds, and heat-treated (autoclaved) whole seeds were compared. Broken seeds, irrespective of LOX presence, supported excellent fungal growth and the highest aflatoxin levels. Autoclaved whole seeds, with or without LOX, produced good fungal growth and aflatoxin levels approaching those of broken seeds. Whole soybean seeds supported sparse fungal growth and relatively low aflatoxin levels. There was no significant difference in aflatoxin production between whole soybean seeds either with or without LOX, although there did seem to be differences among the cultivars tested. The heat treatment eliminated LOX activity (in LOX+ lines), yet aflatoxin levels did not change substantially from the broken seed treatment. Broken soybean seeds possessed LOX activity (in LOX+ lines) and yet yielded the highest aflatoxin levels. The presence of active LOX did not seem to play the determinant role in the susceptibility of soybean seeds to fungal pathogens. Seed coat integrity and seed viability seem to be more important characteristics in soybean seed resistance to aflatoxin contamination. Soybean seeds lacking LOX seem safe from the threat of increased seed pathogen susceptibility.

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Resistance to Aspergillus flavus in Corn Kernels Is Associated with a 14-kDa Protein

Phytopathology ◽

10.1094/phyto.1998.88.4.276 ◽

1998 ◽

Vol 88 (4) ◽

pp. 276-281 ◽

Cited By ~ 95

Author(s):

Z.-Y. Chen ◽

R. L. Brown ◽

A. R. Lax ◽

B. Z. Guo ◽

T. E. Cleveland ◽

...

Keyword(s):

Aspergillus Flavus ◽

Trypsin Inhibitor ◽

Aflatoxin Contamination ◽

Inhibitor Protein ◽

Trypsin Activity ◽

Terminal Sequence ◽

High Concentration ◽

Resistant Varieties ◽

Corn Kernels

Corn genotypes resistant or susceptible to Aspergillus flavus were extracted for protein analysis using a pH 2.8 buffer. The profile of protein extracts revealed that a 14-kDa protein is present in relatively high concentration in kernels of seven resistant corn genotypes, but is absent or present only in low concentration in kernels of six susceptible ones. The N-terminal sequence of this 14-kDa protein showed 100% homology to a corn trypsin inhibitor. The 14-kDa protein purified from resistant varieties also demonstrated in vitro inhibition of both trypsin activity and the growth of A. flavus. This is the first demonstration of antifungal activity of a corn 14-kDa trypsin inhibitor protein. The expression of this protein among tested genotypes may be related to their difference in resistance to A. flavus infection and subsequent aflatoxin contamination.

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Evaluation of Post-harvest Aflatoxin Production in Peanut Germplasm with Resistance to Seed Colonization and Pre-harvest Aflatoxin Contamination

Peanut Science ◽

10.3146/pnut.31.2.0012 ◽

2004 ◽

Vol 31 (2) ◽

pp. 124-134 ◽

Cited By ~ 7

Author(s):

H. Q. Xue ◽

T. G. Isleib ◽

G. A. Payne ◽

G. OBrian

Keyword(s):

Genotypic Variation ◽

Fungal Growth ◽

Aflatoxin Production ◽

Aflatoxin Contamination ◽

Block Designs ◽

Plastic Bags ◽

Arachis Hypogaea L ◽

Seed Colonization ◽

Highly Correlated

Abstract Contamination of peanut (Arachis hypogaea L.) with aflatoxin produced by species of Aspergillus remains a problem for the U.S. peanut industry. Several peanut genotypes were reported to be resistant to in vitro seed colonization by Aspergillus flavus Link ex Fries (IVSCAF), to field seed colonization by A. flavus (FSCAF), or to preharvest aflatoxin contamination (PAC), but few to production of aflatoxin per se. Cotyledons of 39 peanut genotypes reportedly resistant to IVSCAF, FSCAF, or PAC, and eight susceptible to PAC were evaluated in four tests for their ability to support aflatoxin production after inoculation with A. flavus. Cultivars Perry and Gregory were used as checks in each test. Seed cotyledons were separated, manually blanched, inoculated with conidia of A. flavus, placed on moistened filter paper in petri dishes, and incubated for 8 d at 28 C. Dishes were arranged on plastic trays enclosed in plastic bags and stacked with PVC spacers between trays. Incomplete block designs were used for all tests. In each test, none of the genotypes examined was completely resistant to aflatoxin production, but significant genotypic variation was observed in the amount of total aflatoxin accumulated in seeds. Genotypes previously reported to be resistant to IVSCAF, FSCAF, or PAC exhibited differential abilities to support aflatoxin production. PI 590325, PI 590299, PI 290626, and PI 337409 supported reduced levels of aflatoxin, and their degree of resistance was consistent across tests. Fungal growth was highly correlated with aflatoxin production in three tests. The results from this study suggested that there were no absolute relationships of aflatoxin production resistance with IVSCAF, FSCAF, or PAC resistance, but that it should be possible to identify a genotype with high IVSCAF, FSCAF, or PAC resistance and reduced capacity for aflatoxin production by A. flavus.

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