Effect of kebar grass (Biophytum petersianum Klotzsch) leaf extract on the growth and morphological structure of aflatoxigenic Aspergillus flavus

The objective of this study was to investigate the antifungal activity of kebar grass (Biophytum petersianum Klotzsch) extract (KGE) on the mycelial growth, conidiation and morphological structure of two types of aflatoxigenic fungus, which are Aspergillus flavus BCCF 0219 and A. flavus BIO 2236. They were isolated in the three types of model media, namely carbohydrate-enriched medium, fat-enriched medium and protein-enriched medium with five concentrations of KGE (12, 14, 16, 18, and 20 mg/mL) on each media. The best extract concentration of that inhibits the growth of A. flavus BCCF 0219 was found in the carbohydrate-enriched medium (95.7%), which was 12 mg/mL, whereas at A. flavus BIO 2236 was found in the fat-enriched medium (100%), which was 16 mg/mL. Based on SEM observation results, it was found that the mechanisms involved in fungal growth inhibitory by the KGE were by morphological alterations of the hyphal development, and the collapse of the entire hyphae. These findings indicated that KGE as a potential natural antifungal agent, particularly against aflatoxigenic fungi.

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Inhibition of Aflatoxin-Producing Fungi by Welsh Onion Extracts

Journal of Food Protection ◽

10.4315/0362-028x-62.4.414 ◽

1999 ◽

Vol 62 (4) ◽

pp. 414-417 ◽

Cited By ~ 21

Author(s):

J. J. FAN ◽

J. H. CHEN

Keyword(s):

Aspergillus Flavus ◽

Mycelial Growth ◽

Ethanol Extract ◽

Aflatoxin Production ◽

Inhibitory Effects ◽

Welsh Onion ◽

Extract Concentration ◽

Ph Values ◽

Ethanol Extracts ◽

Yeast Extract Sucrose

Welsh onion ethanol extracts were tested for their inhibitory activity against the growth and aflatoxin production of Aspergillus flavus and A. parasiticus. The survival of spores of A. flavus and A. parasiticus depended on both the extract concentration and the exposure time of the spores to the Welsh onion extracts. The mycelial growth of two tested fungi cultured on yeast extract–sucrose broth was completely inhibited in the presence of the Welsh onion ethanol extract at a concentration of 10 mg/ml during 30 days of incubation at 25°C. The extracts added to the cultures also inhibited aflatoxin production at a concentration of 10 mg/ml or permitted only a small amount of aflatoxin production with extract concentration of 5 mg/ml after 2 weeks of incubation. Welsh onion ethanol extracts showed more pronounced inhibitory effects against the two tested aflatoxin-producing fungi than did the same added levels of the preservatives sorbate and propionate at pH values near 6.5.

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Mimosa tenuiflora Aqueous Extract: Role of Condensed Tannins in Anti-Aflatoxin B1 Activity in Aspergillus flavus

Toxins ◽

10.3390/toxins13060391 ◽

2021 ◽

Vol 13 (6) ◽

pp. 391

Author(s):

Christopher Hernandez ◽

Laura Cadenillas ◽

Anwar El Maghubi ◽

Isaura Caceres ◽

Vanessa Durrieu ◽

...

Keyword(s):

Aspergillus Flavus ◽

Aqueous Extract ◽

Aflatoxin B1 ◽

Condensed Tannins ◽

Fungal Growth ◽

Oxidation Reactions ◽

Expression Of Genes ◽

Dependent Inhibition ◽

Interesting Candidate ◽

Mimosa Tenuiflora

Aflatoxin B1 (AFB1) is a potent carcinogenic mycotoxin that contaminates numerous crops pre- and post-harvest. To protect foods and feeds from such toxins without resorting to pesticides, the use of plant extracts has been increasingly studied. The most interesting candidate plants are those with strong antioxidative activity because oxidation reactions may interfere with AFB1 production. The present study investigates how an aqueous extract of Mimosa tenuiflora bark affects both the growth of Aspergillus flavus and AFB1 production. The results reveal a dose-dependent inhibition of toxin synthesis with no impact on fungal growth. AFB1 inhibition is related to a down-modulation of the cluster genes of the biosynthetic pathway and especially to the two internal regulators aflR and aflS. Its strong anti-oxidative activity also allows the aqueous extract to modulate the expression of genes involved in fungal oxidative-stress response, such as msnA, mtfA, atfA, or sod1. Finally, a bio-guided fractionation of the aqueous extract demonstrates that condensed tannins play a major role in the anti-aflatoxin activity of Mimosa tenuiflora bark.

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

Toxins ◽

10.3390/toxins11110646 ◽

2019 ◽

Vol 11 (11) ◽

pp. 646 ◽

Cited By ~ 6

Author(s):

García-Díaz ◽

Patiño ◽

Vázquez ◽

Gil-Serna

Keyword(s):

Aspergillus Flavus ◽

Fungal Growth ◽

Storage Conditions ◽

Aflatoxin Contamination ◽

Small Scale ◽

Low Concentrations ◽

Oil Formulation ◽

Scale Test ◽

Encapsulation Method

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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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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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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Soil-Borne Pests of Peanut in Growers' Fields with Different Cropping Histories in Alabama1

Peanut Science ◽

10.3146/i0095-3679-23-1-7 ◽

1996 ◽

Vol 23 (1) ◽

pp. 36-42 ◽

Cited By ~ 8

Author(s):

K. L. Bowen ◽

A. K. Hagan ◽

J. R. Weeks

Keyword(s):

Aspergillus Flavus ◽

Meloidogyne Incognita ◽

Leaf Spot ◽

Sclerotium Rolfsii ◽

Stem Rot ◽

Peanut Seed ◽

Control Programs ◽

Aflatoxigenic Fungi ◽

Peanut Production ◽

Seed Invasion

Abstract Pest levels and yields of peanut were monitored in growers' fields in 1991 through 1993. Yields ranged from 2085 to 6440 kg/ha and averaged 3947 kg/ha over the 3 yr. Incidence of southern stem rot (SSR) (caused by Sclerotium rolfsii) averaged 7.6 foci (up to 30 cm in length) per 30.5 m row and ranged from 0 to 31.0 foci. Peanut yield tended to be inversely related to incidence of SSR and directly related to the number of years between peanut crops. Incidence of SSR was inversely related to number of years between peanut crops and was consistently greater in fields cropped to peanut every other year compared to other fields with less intensive peanut production. Yields obtained from irrigated fields averaged 11.4% greater than those without irrigation. Leaf spot control programs used by growers provided consistent levels of control. Peanut seed invasion by aflatoxigenic fungi and plant damage by larvae of the lesser cornstalk borer (Elasmopalus lignosellus) generally were low. Seed invasion by Aspergillus flavus-type fungi was positively correlated (P < 0.05) with damage due to lesser cornstalk borer in 1993. Juvenile populations of root knot nematodes (Meloidogyne incognita) were positively correlated (P < 0.001) with incidence of SSR in 1992.

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Control of Aspergillus flavus and aflatoxin production with spices in culture medium and rice

World Mycotoxin Journal ◽

10.3920/wmj2012.1437 ◽

2013 ◽

Vol 6 (1) ◽

pp. 43-50 ◽

Cited By ~ 6

Author(s):

V. Aiko ◽

A. Mehta

Keyword(s):

Aspergillus Flavus ◽

High Performance ◽

Fungal Growth ◽

Aflatoxin Production ◽

Culture Broth ◽

Minimum Inhibitory Concentrations ◽

Food Grains ◽

Star Anise ◽

Aflatoxin B ◽

Layer Chromatography

Cinnamon, cardamom, star anise and clove were studied for their effect on growth of Aspergillus flavus and aflatoxin B1 (AFB1) synthesis. The experiments were carried out in yeast extract sucrose culture broth as well as in rice supplemented with spices. AFB1 produced was analysed qualitatively and quantitatively using thin layer chromatography and high performance liquid chromatography, respectively. At a concentration of 10 mg/ml, cardamom and star anise did not exhibit any antifungal or anti-aflatoxigenic activity in culture broth, whereas cinnamon and clove inhibited A. flavus growth completely. The minimum inhibitory concentrations of cinnamon and clove were 4 and 2 mg/ml, respectively. Concentrations of cinnamon and clove below their minimum inhibitory concentrations showed enhanced fungal growth, while AFB1 synthesis was reduced. Clove inhibited the synthesis of AFB1 significantly up to 99% at concentrations ≥1.0 mg/ml. The spices also inhibited AFB1 synthesis in rice at 5 mg/g, although fungal growth was not inhibited. Clove and cinnamon inhibited AFB1 synthesis significantly up to 99 and 92%, respectively, and star anise and cardamom by 41 and 23%, respectively. The results of this study suggest the use of whole spices rather than their essential oils for controlling fungal and mycotoxin contamination in food grains.

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Fungicidal effect of silver nanoparticles on toxigenic fungi in cocoa

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x2016001200003 ◽

2016 ◽

Vol 51 (12) ◽

pp. 1929-1936 ◽

Cited By ~ 17

Author(s):

Raquel Villamizar-Gallardo ◽

Johann Faccelo Osma Cruz ◽

Oscar Orlando Ortíz-Rodriguez

Keyword(s):

Silver Nanoparticles ◽

Fusarium Solani ◽

Theobroma Cacao ◽

Mycelial Growth ◽

Culture Media ◽

Fungal Growth ◽

Inhibitory Effect ◽

Plant Tissues ◽

Inhibition Effect ◽

Toxigenic Fungi

Abstract: The objective of this work was to evaluate the microbicidal effect of silver nanoparticles (AgNPs) on potentially toxigenic fungi affecting cocoa (Theobroma cacao) crops. These fungi, isolated from diseased cocoa pods, were characterized phenotypically and genotypically. The microbicidal effect was assessed by measuring radial mycelial growth, in synthetic culture media, and at different AgNP concentrations in plant tissues. The inhibition effect was monitored in Petri dishes, and changes in fungal structures were observed through scanning electron microscopy. Two potentially toxigenic fungi were highly prevalent: Aspergillus flavus and Fusarium solani. The inhibition assays, performed in liquid and solid synthetic culture media, showed that AgNPs did not significantly affect the growth of these fungi, even at the highest concentration (100 ppm). By contrast, they showed a positive inhibitory effect in plant tissues, especially in the cortex, when infected with A. flavus, in which an 80 ppm dose completely inhibited fungal growth. However, once fungi have managed to penetrate inside the pods, their growth is unavoidable, and AgNP effect is reduced. On F. solani, the studied nanomaterial only induced some texture and pigmentation changes. The microbicidal effect of chemically synthesized silver nanoparticles is greater in plant tissues than in culture media.

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Morphological alterations in the heart and aorta of rats treated with glucocorticoids

Journal of Morphological Sciences ◽

10.4322/jms.065814 ◽

2015 ◽

Vol 32 (04) ◽

pp. 231-235

Author(s):

R. Dantas ◽

K. Souza ◽

D. Santos ◽

V. Feitosa ◽

E. Fioretto ◽

...

Keyword(s):

Wistar Rats ◽

Histological Analysis ◽

Saline Solution ◽

Morphological Changes ◽

Morphological Structure ◽

Control Group ◽

Morphological Alterations ◽

Heart Chamber ◽

Male Wistar Rats ◽

Synthetic Glucocorticoid

Abstract Introduction: The objective of this study was to analyze the morphological structure of the heart and aorta of rats treated with the synthetic glucocorticoid dexamethasone. Material and Methods: Male Wistar rats were divided into two groups: 08 control rats undergoing treatment with a 0.9% saline solution for 10 days and 08 rats treated for 10 days with dexamethasone (2mg/kg animal weight). Results: Histological analysis detected a mild cardiac hypertrophy and 15% reduction of collagen located in the aorta of animals treated with glucocorticoid when compared to the control group. Conclusion: We conclude that treatment with dexamethasone for a period of 10 consecutive days is able to promote morphological changes in the structure of the heart chamber and, impair morphological structure of aorta.

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