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Molecules (Basel, Switzerland) Oct 2022Fungus continues to attract great attention as a promising pool of biometabolites. Wilh (Aspergillaceae) has established its capacity to biosynthesize a myriad of... (Review)
Review
Fungus continues to attract great attention as a promising pool of biometabolites. Wilh (Aspergillaceae) has established its capacity to biosynthesize a myriad of metabolites belonging to different chemical classes, such as isocoumarins, pyrazines, sterols, indole alkaloids, diketopiperazines, polyketides, peptides, quinones, polyketides, and sesquiterpenoids, revealing various bioactivities that are antimicrobial, cytotoxic, antiviral, anti-inflammatory, insecticidal, and neuroprotective. Additionally, produces a variety of enzymes that could have variable industrial and biotechnological applications. From 1965 until June 2022, 165 metabolites were reported from isolated from different sources. In this review, the formerly separated metabolites from , including their bioactivities and biosynthesis, in addition, the industrial and biotechnological potential of are highlighted.
Topics: Anti-Infective Agents; Anti-Inflammatory Agents; Antiviral Agents; Aspergillus ochraceus; Diketopiperazines; Indole Alkaloids; Isocoumarins; Peptides; Polyketides; Pyrazines; Quinones; Sterols
PubMed: 36235292
DOI: 10.3390/molecules27196759 -
Frontiers in Chemistry 2022, generally known as a food spoilage fungus, is the representative species in section . strains are widely distributed in nature, and usually isolated from cereal,... (Review)
Review
, generally known as a food spoilage fungus, is the representative species in section . strains are widely distributed in nature, and usually isolated from cereal, coffee, fruit, and beverage. Increasing cases suggest acts as human and animal pathogens due to producing the mycotoxins. However, in terms of benefits to mankind, is the potential source of industrial enzymes, and has excellent capability to produce diverse structural products, including polyketides, nonribosomal peptides, diketopiperazine alkaloids, benzodiazepine alkaloids, pyrazines, bis-indolyl benzenoids, nitrobenzoyl sesquiterpenoids, and steroids. This review outlines recent discovery, chemical structure, biosynthetic pathway, and bio-activity of the natural compounds from .
PubMed: 36092677
DOI: 10.3389/fchem.2022.938626 -
Food Research International (Ottawa,... Nov 2023Aspergillus ochraceus is an ochratoxin-producing fungus which contaminates coffee. In this study the antifungal effect of the yeast Hanseniaspora opuntiae on three...
Aspergillus ochraceus is an ochratoxin-producing fungus which contaminates coffee. In this study the antifungal effect of the yeast Hanseniaspora opuntiae on three Aspergillus ochraceus strains (IOC 4417, IOC 4462, Ao 14) was evaluated in vitro and on coffee fruits. H. opuntiae (10 and 10 cells mL) reduced in vitro fungal growth from 82% to 87%, when co-cultivated with A. ochraceus. The yeast cell free supernatant (CFS) inhibited conidial germination from 76.5% to 92.5%, and hyphal growth from 54% to 78%. The yeast (10 and 10 cells mL) applied on coffee fruits delayed fruit decay by A. ochraceus (IOC 4417 and Ao 14) until the 9th day, and was significantly different (p < 0.05) from the controls. Furthermore, the ultrastructure of the yeast-fungus interaction on the coffee fruit surface showed yeast attachment to A. ochraceus hyphae, and morphological alterations in fungal structures, with hyphal abnormalities, such as tortuous hyphae with irregular, non-uniform surface compared to the control without yeast. H. opuntiae showed efficacy as biocontrol agent and, to the best of our knowledge, this is the first study on the antifungal activity of H. opuntiae against A. ochraceus on coffee fruits Nevertheless, application of H. opuntiae to the crop in the field requires further studies.
Topics: Aspergillus ochraceus; Coffee; Fruit; Antifungal Agents
PubMed: 37803726
DOI: 10.1016/j.foodres.2023.113388 -
Mycopathologia Oct 2023
Topics: Humans; Aspergillus ochraceus; Aspergillosis; Antifungal Agents
PubMed: 37477827
DOI: 10.1007/s11046-023-00774-6 -
Archives of Microbiology Dec 2021Mycoremediation is an important process that targets the removal of petroleum hydrocarbons by fungi. Fungi have advantages with their extensive enzymatic systems, rapid...
Mycoremediation is an important process that targets the removal of petroleum hydrocarbons by fungi. Fungi have advantages with their extensive enzymatic systems, rapid adaptation to toxic organic pollutants, and to adverse environmental conditions. In this study, the colorimetric method was used for the preliminary investigation of petroleum degradation with ten fungal strains. Petroleum degradation ability of spore suspension, live biomass (fungal pellet and disc) and cell-free culture supernatant of the potent A. ochraceus strain were investigated by gravimetric analysis. It was found that the fungal disc (94%) was more successful than the spore suspension (87%) in petroleum degradation under physiological conditions determined as pH:5.0, 1% of petroleum concentration, 5% (v/v) of inoculum concentration (with spore suspension) and 1 g/100 mL of inoculum amount (with fungal disc) and 7 days of the incubation period. The degradation rate constant and half-life period of spore suspension were calculated as 0.291 day and t = 0.340 and of the fungal disc were 0.401 day and t = 0.247. Although, 7.5% and 10% (v/v) concentration of cell-free culture supernatant achieved more than 80% petroleum removal, it was not as effective as a fungal disc. According to gas chromatography/mass spectrometry analysis, the fungal disc of A. ochraceus strain degraded long-chain n-alkanes such as C and C more effectively than n-alkanes in the range of C-C. The fact that the A. ochraceus NRRL 3174 strain has a high petroleum degradation capacity as well as being a potent biosurfactant producer will provide a different perspective to advanced mycoremediation studies.
Topics: Alkanes; Aspergillus ochraceus; Biodegradation, Environmental; Hydrocarbons; Petroleum; Soil Pollutants
PubMed: 34599404
DOI: 10.1007/s00203-021-02490-5 -
Environmental Microbiology Jun 2019To date, no demonstration of a direct correlation between the presence of mycoviruses and the quantitative or qualitative modulation of mycotoxins has been shown. In our...
To date, no demonstration of a direct correlation between the presence of mycoviruses and the quantitative or qualitative modulation of mycotoxins has been shown. In our study, we transfected a virus-free ochratoxin A (OTA)-producing isolate of Aspergillus ochraceus with purified mycoviruses from a different A. ochraceus isolate and from Penicillium aurantiogriseum. Among the mycoviruses tested, only Aspergillus ochraceus virus (AoV), a partitivirus widespread in A. ochraceus, caused a specific interaction that led to an overproduction of OTA, which is regulated by the European Commission and is the second most important contaminant of food and feed commodities. Gene expression analysis failed to reveal a specific viral upregulation of the mRNA of genes considered to play a role in the OTA biosynthetic pathway. Furthermore, AoOTApks1, a polyketide synthase gene considered essential for OTA production, is surprisingly absent in the genome of our OTA-producing isolate. The possible biological and evolutionary implications of the mycoviral regulation of mycotoxin production are discussed.
Topics: Aspergillus ochraceus; Biosynthetic Pathways; Fungal Proteins; Fungal Viruses; Ochratoxins; Penicillium; Polyketide Synthases
PubMed: 30289193
DOI: 10.1111/1462-2920.14436 -
Toxins Dec 2023In the context of the mysterious Balkan endemic nephropathy of the 1900s, and the discovery in the 1960s of the potent mycotoxin ochratoxin A, experimental research... (Review)
Review
In the context of the mysterious Balkan endemic nephropathy of the 1900s, and the discovery in the 1960s of the potent mycotoxin ochratoxin A, experimental research projects sought to explore any inter-relationship. Experimental lifetime administration of the toxin to male rats had revealed renal DNA adducts with the toxin, correlated with renal tumours, confirmation of which required molecular evidence. Consequently, production of C-ochratoxin A of a high specific radioactivity was required, practical biosynthetic detail of which had not previously been published. A fermentation study of was carried out during 2002 for a European project, to select for the production of high-quality C-ochratoxin A, necessarily exploring for the maximum diversion of C-sodium acetate into the pentaketide portion of mycotoxin. Experimentation necessarily had to optimise the competitive context of fungal growth dynamics and addition of the biosynthetic precursor in the early days of shaken-flask fermentation before adding the radiolabelled precursor. From optimal fermentation, 50 mg of the C ochratoxin A was supplied within a European project for DNA adduct experimentation, but that proved negative as subsequently published. Experimental description of the radiolabelled ochratoxin A production was later made in a doctoral thesis, but is first publicised here. Further review of the literature reveals an explanation for the published failure to confirm rat DNA/ochratoxin A adduct formation, for which further experimentation is now recommended.
Topics: Male; Animals; Rats; Aspergillus ochraceus; Fermentation; Balkan Nephropathy; Mycotoxins; Ochratoxins
PubMed: 38251225
DOI: 10.3390/toxins16010008 -
Molecules (Basel, Switzerland) Dec 2023Biotransformation of ursonic acid () by two fungal strains CGMCC 3.5324 and CGMCC 3.407 yielded thirteen new compounds (, , -, and -), along with five recognized ones....
Biotransformation of ursonic acid () by two fungal strains CGMCC 3.5324 and CGMCC 3.407 yielded thirteen new compounds (, , -, and -), along with five recognized ones. The structural details of new compounds were determined through spectroscopic examination (NMR, IR, and HR-MS) and X-ray crystallography. Various modifications, including hydroxylation, epoxidation, lactonization, oxygen introduction, and transmethylation, were identified on the ursane core. Additionally, the anti-neuroinflammatory efficacy of these derivatives was assessed on BV-2 cells affected by lipopolysaccharides. It was observed that certain methoxylated and epoxylated derivatives (, , and ) showcased enhanced suppressive capabilities, boasting IC values of 8.2, 6.9, and 5.3 μM. Such ursonic acid derivatives might emerge as potential primary molecules in addressing neurodegenerative diseases.
Topics: Aspergillus ochraceus; Aspergillus oryzae; Crystallography, X-Ray; Biotransformation
PubMed: 38138433
DOI: 10.3390/molecules28247943 -
Foods (Basel, Switzerland) Oct 2023and are important pathogenic fungi that pose a serious threat because of their ability to produce mycotoxins, including ochratoxin A (OTA) and aflatoxins (AFs). The...
and are important pathogenic fungi that pose a serious threat because of their ability to produce mycotoxins, including ochratoxin A (OTA) and aflatoxins (AFs). The main method of reducing these pathogens is the use of chemical fungicides, though recently there has been a focus on finding biological control agents. The obtained results from this study indicate the great potential of two wild yeast strains, PP3 and D10, in the biological control of and and reductions in the amount of OTA and AFs they produce. In vitro, the growth of the mycelium of pathogens was reduced by 41.21% to 53.64%, and spore germination was inhibited by 58.39% to 71.22%. Both yeast strains produced the enzymes chitinase, β-1,3-glucanase, and amylase, and PP3 additionally produced protease and cellulase. This yeast strain also had the ability to grow over a wide range of temperature (4-30 °C), salinity (0-12%) and pH (4-11) conditions. No growth of the yeast was observed at 37 °C, nor any biogenic amines or hydrogen sulfide production. Adding the tested yeast inoculum to the dough reduced OTA (within 14.55-21.80%) and AFs (within 18.10-25.02%) in the model bread.
PubMed: 37893764
DOI: 10.3390/foods12203871 -
Toxicon : Official Journal of the... Jul 2021Grains are susceptible to contamination by molds; some cause spoilage and others produce certain mycotoxins that cause a serious health threat to humans and animals....
Grains are susceptible to contamination by molds; some cause spoilage and others produce certain mycotoxins that cause a serious health threat to humans and animals. Aspergillus flavus and Aspergillus ochraceus and their mycotoxins, aflatoxins and ochratoxin A, are natural contaminants of various agricultural commodities. Control of these molds and their mycotoxins in food commodities is of utmost importance; therefore, the target of this research was to explore the effects of gamma irradiation doses on the growth of A. flavus and A. ochraceus in artificially inoculated yellow maize as well as on the production of aflatoxin B1, ochratoxin A, and the formation of toxins in maize. The irradiated dose of 6.0 kGy was found to completely inhibit the growth of the two molds, while a dose of 4.5 kGy reduced the production of their mycotoxins. Maximum degradation of the formed aflatoxins and ochratoxin A in maize occurred at 20 kGy, with best reduction rates of 40.1%, 33.3%, and 61.1% observed for aflatoxin B1, aflatoxin B2, and ochratoxin A, respectively. We recommend grains irradiation by gamma radiation at 6.0 kGy to decontaminate mycotoxin-producing molds before they produce mycotoxins. The study represents a proactive, efficient, and potent method for avoiding potential contamination of fungus during grains storage and transfer for one to two months.
Topics: Aflatoxins; Animals; Aspergillus flavus; Aspergillus ochraceus; Food Contamination; Humans; Mycotoxins; Ochratoxins; Zea mays
PubMed: 33961848
DOI: 10.1016/j.toxicon.2021.04.029