ANTIFUNGAL ACTIVITY OF KEBAR GRASS (BIOPHYTUM PETERSIANUM KLOTSZCH) STEM ETHANOL EXTRACT ON THE GROWTH OF AFLATOXIGENIC ASPERGILLUS FLAVUS IN CORN AND PEANUT-BASED MEDIA

Cereals and legumes are very easily damaged by fungi, including toxigenic fungi species such as Aspergillus flavus which can produce aflatoxins. Various methods have been carried out to reduce aflatoxin contamination in foods, including the use of plant extracts based antimicrobial compounds. One of indigenous herbs in Papua that has potency as natural antimicrobial is Kebar grass (Biophytum petersianum Klotszch). The aims of this study were to investigate the chemical composition and the effect of kebar grass stem ethanol extract on the growth of toxigenic A. flavus. Kebar grass stem ethanol extract at concentrations of 5, 10, 15, 20, 25, and 30 mg mL-1 was tested on the growth of A. flavus in two types media i.e. corn based-medium and peanut based-medium. The result showed that kebar grass stem ethanol extract at concentration of 15 mg ml-1 in corn based-medium and peanut based-medium caused 100% growth inhibition of A. flavus. The major compounds in kebar grass stem ethanol extract were: Pyrocatechol, Methylhydrazine hydrochloride, 2-Fluoropropane, Isobutyric acid, 2,6-Dimethoxyphenol. The results obtained from this study suggested that the ethanol extract of the kebar grass stem can be used as a natural antifungal agent to inhibit the growth of aflatoxigenic A. flavus.

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Occidiofungin is the key metabolite for antifungal activity of the endophytic bacterium Burkholderia sp. MS455 against Aspergillus flavus

Phytopathology ◽

10.1094/phyto-06-21-0225-r ◽

2021 ◽

Author(s):

Jiayuan Jia ◽

Emerald Ford ◽

Sarah Hobbs ◽

Sonya Baird ◽

Shien Lu

Keyword(s):

Antifungal Activity ◽

Aspergillus Flavus ◽

Safety Concern ◽

Regulatory Gene ◽

Genomic Analysis ◽

Endophytic Bacterium ◽

Aflatoxin Contamination ◽

Plant Production ◽

Antifungal Compound ◽

Buffer Control

Aflatoxin is a secondary metabolite produced by Aspergillus fungi and presents a major food safety concern globally. Among the available methods for prevention and control of aflatoxin, the application of antifungal bacteria has gained favorability in recent years. An endophytic bacterium MS455, isolated from soybean, exhibited broad-spectrum antifungal activity against economically important pathogens, including Aspergillus flavus. MS455 was identified as a strain of Burkholderia based on genomic analysis. Random and site-specific mutations were employed in discovery of the genes that share high homology to the ocf gene cluster of Burkholderia contaminans strain MS14, which is responsible for production of the antifungal compound occidiofungin. RNA-seq analysis demonstrated ORF1, a homolog to the ambR1 LuxR-type regulatory gene, regulates occidiofungin biosynthesis in MS455. Additionally, a total of 284 differentially expressed genes, including 138 up-regulated, and 146 down-regulated genes, suggesting that, in addition to its role in occidiofungin production, ORF1 is involved in expression of multiple genes, especially those involved in ornibactin biosynthesis. Plate bioassays showed the growth of A. flavus was significantly inhibited by the wild-type strain MS455 as compared with the ORF1 mutant. Similarly, corn kernel assays showed that growth of A. flavus and aflatoxin production were reduced significantly by MS455 as compared with buffer control and the ORF1 mutant. Collectively, the results demonstrated that production of occidiofungin is essential for antifungal activity of the endophytic bacterium MS455. This research has provided insights to understanding antifungal mechanisms of MS455 and development of biological approaches to prevent aflatoxin contamination in plant production.

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Molecular Identification of Selected Streptomyces Strains Isolated from Mexican Tropical Soils and their Anti-Candida Activity

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph16111913 ◽

2019 ◽

Vol 16 (11) ◽

pp. 1913

Author(s):

Diana Escalante-Réndiz ◽

Susana de-la-Rosa-García ◽

Raúl Tapia-Tussell ◽

Jesús Martín ◽

Fernando Reyes ◽

...

Keyword(s):

Antifungal Activity ◽

Polyketide Synthase ◽

Inhibitory Concentration ◽

Ethanol Extract ◽

Tropical Soils ◽

Antifungal Compound ◽

Type I ◽

Antimicrobial Compounds ◽

Organic Extract ◽

Streptomyces Genus

The increasing incidence of Candida albicans infections and resistance to current antifungal therapies has led to the search for new and more effective antifungal compounds. Actinobacterial species from the Streptomyces genus are recognized as some of the major producers of antimicrobial compounds. Therefore, the aims of this study were: (1) the identification of Streptomyces strains isolated from Mexican tropical acidic soils, (2) the evaluation of their antifungal activity on C. albicans, and (3) the exploration of the presence of polyketide synthase genes in their genome and antifungal secondary metabolites in their extracts. Four actinobacterial strains, isolated from previously unexplored soils with antibacterial antecedents, were selected. These strains were identified as Streptomyces angustmyceticus S6A-03, Streptomyces manipurensis S3A-05 and S3A-09, and Streptomyces parvisporogenes S2A-04, according to their molecular analyses. The ethanol extract of the lyophilized supernatant of S. parvisporogenes displayed the most interesting antifungal activity against C. albicans, with a minimum inhibitory concentration (MIC) of 0.5 mg/mL. Type I polyketide synthase (PKS-I) and non-ribosomal peptide synthase (NRPS) genes were detected in all strains. In addition, type II PKS genes (PKS-II) were also found in S. manipurensis S3A-05 and S. parvisporogenes. LC-UV-HRMS analysis of the active organic extract of S. parvisporogenes indicated the presence of the known antifungal compound carbazomycin G as the major component.

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Chemical Composition and Antifungal Activity of Ocimum basilicum L. Essential Oil

Open Access Macedonian Journal of Medical Sciences ◽

10.3889/oamjms.2015.082 ◽

2015 ◽

Vol 3 (3) ◽

pp. 374-379 ◽

Cited By ~ 18

Author(s):

Neveen Helmy Abou El-Soud ◽

Mohamed Deabes ◽

Lamia Abou El-Kassem ◽

Mona Khalil

Keyword(s):

Chemical Composition ◽

Antifungal Activity ◽

Essential Oil ◽

Aspergillus Flavus ◽

Aflatoxin B1 ◽

Fungal Growth ◽

Ocimum Basilicum ◽

Growth Media ◽

Oil Concentration

BACKGROUND: The leaves of Ocimum basilicum L. (basil) are used in traditional cuisine as spices; its essential oil has found a wide application in perfumery, dental products as well as antifungal agents.AIM: To assess the chemical composition as well as the in vitro antifungal activity of O. basilicum L. essential oil against Aspergillus flavus fungal growth and aflatoxin B1 production.MATERIAL AND METHODS: The essential oil of O. basilicum was obtained by hydrodistillation and analysed using gas chromatography (GC) and GC coupled with mass spectrometry (GC/MS). The essential oil was tested for its effects on Aspergillus flavus (A. flavus) mycelial growth and aflatoxin B1 production in Yeast Extract Sucrose (YES) growth media. Aflatoxin B1 production was determined by high performance liquid chromatography (HPLC).RESULTS: Nineteen compounds, representing 96.7% of the total oil were identified. The main components were as follows: linalool (48.4%), 1,8-cineol (12.2%), eugenol (6.6%), methyl cinnamate (6.2%), α-cubebene (5.7%), caryophyllene (2.5%), β-ocimene (2.1%) and α-farnesene (2.0%).The tested oil showed significant antifungal activity that was dependent on the used oil concentration. The complete inhibition of A. flavus growth was observed at 1000 ppm oil concentration, while marked inhibition of aflatoxin B1 production was observed at all oil concentrations tested (500, 750 and 1000 ppm).CONCLUSION: These results confirm the antifungal activities of O. basilicum L. oil and its potential use to cure mycotic infections and act as pharmaceutical preservative against A. flavus growth and aflatoxin B1 production.

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Copper-Chitosan Nanocomposite Hydrogels Against Aflatoxigenic Aspergillus flavus from Dairy Cattle Feed

Journal of Fungi ◽

10.3390/jof6030112 ◽

2020 ◽

Vol 6 (3) ◽

pp. 112

Author(s):

Kamel A. Abd-Elsalam ◽

Mousa A. Alghuthaymi ◽

Ashwag Shami ◽

Margarita S. Rubina ◽

Sergey S. Abramchuk ◽

...

Keyword(s):

Electron Microscopy ◽

Antifungal Activity ◽

Aspergillus Flavus ◽

Uv Light ◽

Peanut Meal ◽

High Concentration ◽

Fungal Cell ◽

X Ray ◽

Toxigenic Fungi

The integration of copper nanoparticles as antifungal agents in polymeric matrices to produce copper polymer nanocomposites has shown excellent results in preventing the growth of a wide variety of toxigenic fungi. Copper-chitosan nanocomposite-based chitosan hydrogels (Cu-Chit/NCs hydrogel) were prepared using a metal vapor synthesis (MVS) and the resulting samples were described by transmission electron microscopy (TEM), X-ray fluorescence analysis (XRF), and small-angle X-ray scattering (SAXS). Aflatoxin-producing medium and VICAM aflatoxins tests were applied to evaluate their ability to produce aflatoxins through various strains of Aspergillus flavus associated with peanut meal and cotton seeds. Aflatoxin production capacity in four fungal media outlets revealed that 13 tested isolates were capable of producing both aflatoxin B1 and B2. Only 2 A. flavus isolates (Af11 and Af 20) fluoresced under UV light in the A. flavus and parasiticus Agar (AFPA) medium. PCR was completed using two specific primers targeting aflP and aflA genes involved in the synthetic track of aflatoxin. Nevertheless, the existence of aflP and aflA genes indicated some correlation with the development of aflatoxin. A unique DNA fragment of the expected 236 bp and 412 bp bands for aflP and aflA genes in A. flavus isolates, although non-PCR fragments have been observed in many other Aspergillus species. This study shows the antifungal activity of Cu-Chit/NCs hydrogels against aflatoxigenic strains of A. flavus. Our results reveal that the antifungal activity of nanocomposites in vitro can be effective depending on the type of fungal strain and nanocomposite concentration. SDS-PAGE and native proteins explain the apparent response of cellular proteins in the presence of Cu-Chit/NCs hydrogels. A. flavus treated with a high concentration of Cu-Chit/NCs hydrogels that can decrease or produce certain types of proteins. Cu-Chit/NCs hydrogel decreases the effect of G6DP isozyme while not affecting the activity of peroxidase isozymes in tested isolates. Additionally, microscopic measurements of scanning electron microscopy (SEM) showed damage to the fungal cell membranes. Cu-Chit/NCS hydrogel is an innovative nano-biopesticide produced by MVS is employed in food and feed to induce plant defense against toxigenic fungi.

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Chemical composition and antifungal activity of propolis on Aspergillus flavus

Bioscience Journal ◽

10.14393/bj-v34n5a2018-36601 ◽

2018 ◽

pp. 1298-1307 ◽

Cited By ~ 1

Author(s):

Alexandre Lorini ◽

Carmen Wobeto ◽

Solange Maria Bonaldo ◽

Sílvia de Carvalho Campos Botelho ◽

Adilson Paulo Sinhorin

Keyword(s):

Chemical Composition ◽

Antifungal Activity ◽

Aspergillus Flavus

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Chemical Composition of Apiaceae Family Essential Oils from Different Plants and in-vitro Antimicrobial Activities on Probiotic Microorganisms

10.47363/jpr/2021(3)135 ◽

2021 ◽

pp. 1-4

Author(s):

Alper Çimik ◽

Keyword(s):

Chemical Composition ◽

Antifungal Activity ◽

Essential Oils ◽

Human Body ◽

Antimicrobial Agents ◽

Antimicrobial Activities ◽

Natural Antimicrobial ◽

Ms Analysis ◽

Antimicrobial And Antifungal Activity

Coriander, fennel, caraway and anise species which have major characteristic specialities of Apiaceae family, have antimicrobial activities on pathogene microorganisms. Probiotic microorganisms have fundamental effects on human body and extermination of probiotics causes many diseases. In this study, it was aimed to determine investigate probiotic resistance against natural antimicrobial agents (as essential oils) compare to pathogenes in previous studies. Analysis of essential oils (Eos) from were analyzed by GC-FID and GC/MS, analysis of Eos antimicrobial and antifungal activity from were analyzed by Microdilution test (as described in CLSI). Linalool (%74.927), (E)-anethole (%68.239), carvone (%61.087) and (E)-anethole (%95.577) were found as major compounds of EOs respectively. All essential oils have antimicrobial activities on probiotic microorganisms.

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The 'omics' tools: genomics, proteomics, metabolomics and their potential for solving the aflatoxin contamination problem

World Mycotoxin Journal ◽

10.3920/wmj2008.x001 ◽

2008 ◽

Vol 1 (1) ◽

pp. 3-12 ◽

Cited By ~ 30

Author(s):

D. Bhatnagar ◽

K. Rajasekaran ◽

G. Payne ◽

R. Brown ◽

J. Yu ◽

...

Keyword(s):

Aspergillus Flavus ◽

Aflatoxin Contamination ◽

Control Measures ◽

Clear Understanding ◽

Fungal Invasion ◽

Toxigenic Fungi ◽

Additional Information ◽

Time Control ◽

Crop Resistance ◽

Food And Feed

Aflatoxins are highly carcinogenic secondary metabolites produced primarily by the fungi Aspergillus flavus and Aspergillus parasiticus. Aflatoxin contamination of food and feed is an age old problem of particular concern over the last four decades. Now, for the first time control measures for this problem appear within reach. For practical and sustainable control of aflatoxin contamination to be realised, however, additional information is needed rather rapidly, particularly for understanding the specific molecular factors (both in the plant and the fungus) involved during host plant-fungus interaction. The information derived from the use of novel tools such as genomics, proteomics and metabolomics provides us with the best and the quickest opportunity to achieve a clear understanding of the survival of toxigenic fungi in the field, the ability of the fungus to invade crops, and the process of toxin contamination under various environmental conditions. Significant progress has been made recently in understanding the genomic makeup of the most significant aflatoxin producing field fungus, namely Aspergillus flavus. Progress also has been made in the study of host crop resistance to fungal invasion through the use of proteomics. The information available on production of aflatoxin and other metabolites by Aspergillus flavus is reasonably extensive, although the application of metabolomics as a tool in this study is relatively new. In this review there is a discussion of the use of genomics, proteomics and metabolomics in deriving the requisite information for developing effective strategies to interrupt the machinery in the fungus for production of these toxins, as well as to assist in the development of host-resistance against fungal invasion and aflatoxin contamination of crops.

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Protein Profiles and Antifungal Activities of Kernel Extracts from Corn Genotypes Resistant and Susceptible to Aspergillus flavus

Journal of Food Protection ◽

10.4315/0362-028x-61.1.98 ◽

1998 ◽

Vol 61 (1) ◽

pp. 98-102 ◽

Cited By ~ 32

Author(s):

B. Z. GUO ◽

R. L. BROWN ◽

A. R. LAX ◽

T. E. CLEVELAND ◽

J. S. RUSSIN ◽

...

Keyword(s):

Antifungal Activity ◽

Aspergillus Flavus ◽

Gel Electrophoresis ◽

Polyacrylamide Gel Electrophoresis ◽

Aflatoxin Contamination ◽

Polyacrylamide Gel ◽

Protein Profiles ◽

Mechanisms Of Resistance ◽

Resistance To Infection ◽

Resistant Genotypes

Mechanisms of resistance to infection by the fungus Aspergillus flavus and accumulation of aflatoxin were studied in kernels of resistant (GT-MAS:gk, Mp420) and susceptible (Pioneer 3154, Deltapine G-4666) corn genotypes. Proteins from kernel extracts of corn genotypes were analyzed by several methods of polyacrylamide gel electrophoresis. Consistent differences in protein profiles were detected among genotypes. Several proteins were unique to or present in greater concentration in resistant genotypes, whereas others were present only in susceptible genotypes. Extracts of resistant kernels showed markedly greater antifungal activity against A. flavus than did susceptible kernel extracts. Results from the present study suggest a role for kernel proteins in resistance to A. flavus infection and aflatoxin contamination in corn genotypes GT-MAS:gk and Mp420.

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