comparison of species composition and fumonisin production in aspergillus section nigri populations in maize kernels from usa and italy.fumonisin contamination of maize is considered a serious problem in most maize-growing regions of the world, due to the widespread occurrence of these mycotoxins and their association with toxicosis in livestock and humans. fumonisins are produced primarily by species of fusarium that are common in maize grain, but also by some species of aspergillus sect. nigri, which can also occur on maize kernels as opportunistic pathogens. understanding the origin of fumonisin contamination in maize is a ke ...201425087207
characterization of aspergillus section nigri species populations in vineyard soil using droplet digital pcr.identification of populations of aspergillus section nigri species in environmental samples using traditional methods is laborious and impractical for large numbers of samples. we developed species-specific primers and probes for quantitative droplet digital pcr (ddpcr) to improve sample throughput and simultaneously detect multiple species in each sample. the ddpcr method was used to distinguish aspergillus niger, aspergillus welwitschiae, aspergillus tubingensis and aspergillus carbonarius in ...201627604045
genetic diversity of aspergillus species isolated from onychomycosis and aspergillus hongkongensis sp. nov., with implications to antifungal susceptibility testing.thirteen aspergillus isolates recovered from nails of 13 patients (fingernails, n=2; toenails, n=11) with onychomycosis were characterized. twelve strains were identified by multilocus sequencing as aspergillus spp. (aspergillus sydowii [n=4], aspergillus welwitschiae [n=3], aspergillus terreus [n=2], aspergillus flavus [n=1], aspergillus tubingensis [n=1], and aspergillus unguis [n=1]). isolates of a. terreus, a. flavus, and a. unguis were also identifiable by matrix-assisted laser desorption/i ...201626658315
analysis of the mat1-1 and mat1-2 gene ratio in black koji molds isolated from meju.aspergillus luchuensis is known as an industrially important fungal species used for making fermented foods such as awamori and shochu in japan, makgeolli and meju in korea, and pu-erh tea in china. nonetheless, this species has not yet been widely studied regarding mating-type genes. in this study, we examined the mat1-1 and mat1-2 gene ratio in black koji molds (a. luchuensis, aspergillus niger, and aspergillus tubingensis) and in aspergillus welwitschiae isolated from meju, a fermented soybea ...201628154484
product ion filtering with rapid polarity switching for the detection of all fumonisins and aal-toxins.fumonisins and aal-toxins are structurally similar mycotoxins that contaminate agricultural crops and foodstuffs. traditional analytical screening methods are designed to target the known compounds for which standards are available but there is clear evidence that many other derivatives exist and could be toxic. a fast, semi-targeted method for the detection of all known fumonisins, aal-toxins and related emerging toxins is required.201526467225
prospecting for the incidence of genes involved in ochratoxin and fumonisin biosynthesis in brazilian strains of aspergillus niger and aspergillus welwitschiae.aspergillus niger "aggregate" is an informal taxonomic rank that represents a group of species from the section nigri. among a. niger "aggregate" species aspergillus niger sensu stricto and its cryptic species aspergillus welwitschiae (=aspergillus awamori sensu perrone) are proven as ochratoxin a and fumonisin b2 producing species. a. niger has been frequently found in tropical and subtropical foods. a. welwitschiae is a new species, which was recently dismembered from the a. niger taxon. these ...201626803270
molecular characterization of black aspergillus species from onion and their potential for ochratoxin a and fumonisin b2 production.onion bulbs can become contaminated with various molds during the storage period, the most important causal agents being black aspergilli (aspergillus section nigri). taxonomic studies have revealed that this group of aspergillus contains many species that cannot be reliably identified using standard morphological methods. therefore, it is necessary to define the fungus causing this problem in the onion exactly, especially since some species assigned to section nigri are well known as ochratoxin ...201525713980
drug sensitivity and resistance mechanism in aspergillus section nigri strains from japan.aspergillus niger and its related species, known as aspergillus section nigri, are ubiquitously distributed across the globe and are often isolated from clinical specimens. in japan, aspergillus section nigri is second most often isolated from clinical specimens following aspergillus fumigatus we determined the species of aspergillus section nigri isolated in japan by dna sequencing of partial β-tubulin genes and investigated drug susceptibility by the clsi m38-a2 method. the collection containe ...201728607016
mechanistic insight into the biosynthesis and detoxification of fumonisin mycotoxins.fumonisins, notably fb1, fb2, fb3, and fb4, are economically important mycotoxins produced by a number fusarium sp. that occur on corn, rice, and sorghum as well as by aspergillus sp. on grapes. the fumonisin scaffold is comprised of a c18 polyketide backbone functionalized with two tricarballylic esters and an alanine derived amine. these functional groups contribute to fumonisin's ability to inhibit sphingolipid biosynthesis in animals, plants, and yeasts. we report for the first time the isol ...201627444057
detection and discrimination of four aspergillus section nigri species by pcr.species of aspergillus section nigri are not easily distinguished by traditional morphological techniques, and typically are identified by dna sequencing methods. we developed four pcr primers to distinguish between aspergillus niger, aspergillus welwitschiae, aspergillus carbonarius and aspergillus tubingensis, based on species-conserved differences in the calmodulin gene sequence. pcr amplification from total dna using these primers was species specific; no amplification occurred from nontarge ...201525384730
diversity of black aspergilli isolated from raisins in argentina: polyphasic approach to species identification and development of scar markers for aspergillus ibericus.aspergillus section nigri is a heterogeneous fungal group including some ochratoxin a producer species that usually contaminate raisins. the section contains the series carbonaria which includes the toxigenic species aspergillus carbonarius and nontoxigenic aspergillus ibericus that are phenotypically undistinguishable. the aim of this study was to examine the diversity of black aspergilli isolated from raisins and to develop a specific genetic marker to distinguish a. ibericus from a. carbonari ...201526114593
occurrence and biodiversity of aspergillus section nigri on 'tannat' grapes in uruguay.ochratoxin a (ota) is a nephrotoxic mycotoxin which has been found worldwide as a contaminant in wines. it is produced on grapes mainly by molds from aspergillus section nigri. this study has demonstrated for the first time the occurrence of black aspergilli on tannat grapes from uruguay, in a two year survey. aspergillus uvarum (uniseriate) and aspergillus welwitschiae (from aspergillusniger aggregate) were the prevalent species whereas aspergillus carbonarius which is considered the main ota p ...201626398282
diversity of mycotoxin-producing black aspergilli in canadian vineyards.several aspergillus species produce ochratoxin a (ota) and/or fumonisins on wine and table grapes. the relevant species and their mycotoxins have been investigated in a number of wine-producing regions around the world; however, similar data have not been reported for canadian vineyards. a multiyear survey of black aspergilli in niagara, on, vineyards was conducted to determine the diversity of species present and to assess the risk of ota and fumonisin contamination of wine grapes from this reg ...201626837797
aspergillus luchuensis, an industrially important black aspergillus in east asia.aspergilli known as black- and white-koji molds which are used for awamori, shochu, makgeolli and other food and beverage fermentations, are reported in the literature as a. luchuensis, a. awamori, a. kawachii, or a. acidus. in order to elucidate the taxonomic position of these species, available ex-type cultures were compared based on morphology and molecular characters. a. luchuensis, a. kawachii and a. acidus showed the same banding patterns in rapd, and the three species had the same rdna-it ...201323723998
aspergillus section nigri as contributor of fumonisin b(2) contamination in maize.fumonisins (fbs), which are carcinogenic mycotoxins, are known to be typically produced by several phytopathogenic fungal species belonging to the genus fusarium. f. proliferatum and f. verticillioides, two important pathogens of maize worldwide, are the most common species that produce fbs. the main fbs produced by these species are fb1, fb2 and fb3. moreover, recently, fungal strains belonging to aspergillus niger have been also reported to produce fbs (in particular, fb2 and fb4). in a survey ...201424313896
variation in the fumonisin biosynthetic gene cluster in fumonisin-producing and nonproducing black aspergilli.the ability to produce fumonisin mycotoxins varies among members of the black aspergilli. previously, analyses of selected genes in the fumonisin biosynthetic gene (fum) cluster in black aspergilli from california grapes indicated that fumonisin-nonproducing isolates of aspergillus welwitschiae lack six fum genes, but nonproducing isolates of aspergillus niger do not. in the current study, analyses of black aspergilli from grapes from the mediterranean basin indicate that the genomic context of ...201425281783
data on the presence or absence of genes encoding essential proteins for ochratoxin and fumonisin biosynthesis in aspergillus niger and aspergillus welwitschiae.we present the multiplex pcr data for the presence/absence of genes involved in ota and fb2 biosynthesis in aspergillus niger/aspergillus welwitschiae strains isolated from different food substrates in brazil. among the 175 strains analyzed, four mpcr profiles were found: profile 1 (17%) highlights strains harboring in their genome the pks, radh and the fum8 genes. profile 2 (3.5%) highlights strains harboring genes involved in ota biosynthesis i.e. radh and pks. profile 3 (51.5%) highlights str ...201627054181
variation in fumonisin and ochratoxin production associated with differences in biosynthetic gene content in aspergillus niger and a. welwitschiae isolates from multiple crop and geographic origins.the fungi aspergillus niger and a. welwitschiae are morphologically indistinguishable species used for industrial fermentation and for food and beverage production. the fungi also occur widely on food crops. concerns about their safety have arisen with the discovery that some isolates of both species produce fumonisin (fb) and ochratoxin a (ota) mycotoxins. here, we examined fb and ota production as well as the presence of genes responsible for synthesis of the mycotoxins in a collection of 92 a ...201627667988
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