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Sample records for aspergillus caelatus strain

  1. Aflatoxigenic Aspergillus flavus and Aspergillus parasiticus strains in Hungarian maize fields.

    Science.gov (United States)

    Sebők, Flóra; Dobolyi, Csaba; Zágoni, Dóra; Risa, Anita; Krifaton, Csilla; Hartman, Mátyás; Cserháti, Mátyás; Szoboszlay, Sándor; Kriszt, Balázs

    2016-12-01

    Due to the climate change, aflatoxigenic Aspergillus species and strains have appeared in several European countries, contaminating different agricultural commodities with aflatoxin. Our aim was to screen the presence of aflatoxigenic fungi in maize fields throughout the seven geographic regions of Hungary. Fungi belonging to Aspergillus section Flavi were isolated in the ratio of 26.9% and 42.3% from soil and maize samples in 2013, and these ratios decreased to 16.1% and 34.7% in 2014. Based on morphological characteristics and the sequence analysis of the partial calmodulin gene, all isolates proved to be Aspergillus flavus, except four strains, which were identified as Aspergillus parasiticus. About half of the A. flavus strains and all the A. parasiticus strains were able to synthesize aflatoxins. Aflatoxigenic Aspergillus strains were isolated from all the seven regions of Hungary. A. parasiticus strains were found in the soil of the regions Southern Great Plain and Southern Transdanubia and in a maize sample of the region Western Transdanubia. In spite of the fact that aflatoxins have rarely been detected in feeds and foods in Hungary, aflatoxigenic A. flavus and A. parasiticus strains are present in the maize culture throughout Hungary posing a potential threat to food safety.

  2. Phosphate solubilizing ability of two Arctic Aspergillus niger strains

    Directory of Open Access Journals (Sweden)

    Shiv Mohan Singh,

    2011-06-01

    Full Text Available Many filamentous fungi were isolated from the soils of Ny-Ålesund, Spitsbergen, Svalbard, and were screened in vitro for their phosphate solubilizing ability. Two strains of Aspergillus niger showed good tricalcium phosphate (TCP solubilizing ability in Pikovskaya's medium. The TCP solubilization index was calculated at varying levels of pH and temperatures. The ability of Aspergillus niger strain-1 to solubilize and release inorganic-P was 285 µg ml–1, while Aspergillus niger strain-2 solubilized 262 µg ml–1 from 0.5% TCP after seven days. This is the first report of TCP solubilization by Arctic strains that may serve as very good phosphate solubilizers in the form of biofertilizer.

  3. Comparison of the aflR gene sequences of strains in Aspergillus section Flavi.

    Science.gov (United States)

    Lee, Chao-Zong; Liou, Guey-Yuh; Yuan, Gwo-Fang

    2006-01-01

    Aflatoxins are polyketide-derived secondary metabolites produced by Aspergillus parasiticus, Aspergillus flavus, Aspergillus nomius and a few other species. The toxic effects of aflatoxins have adverse consequences for human health and agricultural economics. The aflR gene, a regulatory gene for aflatoxin biosynthesis, encodes a protein containing a zinc-finger DNA-binding motif. Although Aspergillus oryzae and Aspergillus sojae, which are used in fermented foods and in ingredient manufacture, have no record of producing aflatoxin, they have been shown to possess an aflR gene. This study examined 34 strains of Aspergillus section Flavi. The aflR gene of 23 of these strains was successfully amplified and sequenced. No aflR PCR products were found in five A. sojae strains or six strains of A. oryzae. These PCR results suggested that the aflR gene is absent or significantly different in some A. sojae and A. oryzae strains. The sequenced aflR genes from the 23 positive strains had greater than 96.6 % similarity, which was particularly conserved in the zinc-finger DNA-binding domain. The aflR gene of A. sojae has two obvious characteristics: an extra CTCATG sequence fragment and a C to T transition that causes premature termination of AFLR protein synthesis. Differences between A. parasiticus/A. sojae and A. flavus/A. oryzae aflR genes were also identified. Some strains of A. flavus as well as A. flavus var. viridis, A. oryzae var. viridis and A. oryzae var. effuses have an A. oryzae-type aflR gene. For all strains with the A. oryzae-type aflR gene, there was no evidence of aflatoxin production. It is suggested that for safety reasons, the aflR gene could be examined to assess possible aflatoxin production by Aspergillus section Flavi strains.

  4. Two new aflatoxin producing species, and an overview of Aspergillus section Flavi

    DEFF Research Database (Denmark)

    Varga, J.; Frisvad, Jens Christian; Samson, R. A.

    2011-01-01

    this section. The data indicate that Aspergillus section Flavi involves 22 species, which can be grouped into seven clades. Two new species, A. pseudocaelatus sp. nov. and A. pseudonomius sp. nov. have been discovered, and can be distinguished from other species in this section based on sequence data...... and extrolite profiles. Aspergillus pseudocaelatus is represented by a single isolate collected from Arachis burkartii leaf in Argentina, is closely related to the non-aflatoxin producing A. caelatus, and produces aflatoxins B & G, cyclopiazonic acid and kojic acid, while A. pseudonomius was isolated from...... insects and soil in the USA. This species is related to A. nomius, and produces aflatoxin B-1 (but not G-type aflatoxins), chrysogine and kojic acid. In order to prove the aflatoxin producing abilities of the isolates, phylogenetic analysis of three genes taking part in aflatoxin biosynthesis, including...

  5. Volatile compounds of Aspergillus strains with different abilities to produce ochratoxin A.

    Science.gov (United States)

    Jeleń, Henryk H; Grabarkiewicz-Szczesna, Jadwiga

    2005-03-09

    Volatile compounds emitted by Aspergillus strains having different abilities to produce ochratoxin A were investigated. Thirteen strains of Aspergillus ochraceus, three belonging to the A. ochraceus group, and eight other species of Aspergillus were examined for their abilities to produce volatile compounds and ochratoxin A on a wheat grain medium. The profiles of volatile compounds, analyzed using SPME, in all A. ochraceus strains, regardless of their toxeginicity, were similar and comprised mainly of 1-octen-3-ol, 3-octanone, 3-octanol, 3-methyl-1-butanol, 1-octene, and limonene. The prevailing compound was always 1-octen-3-ol. Mellein, which forms part of the ochratoxin A molecule, was found in both toxigenic and nontoxigenic strains. Volatile compounds produced by other Aspergillus strains were similar to those of A. ochraceus. Incubation temperatures (20, 24, and 27 degrees C) and water content in the medium (20, 30, and 40%) influenced both volatile compounds formation and ochratoxin A biosynthesis efficiency, although conditions providing the maximum amount of volatiles were different from those providing the maximum amount of ochratoxin A. The pattern of volatiles produced by toxigenic A. ochraceus strains does not facilitate their differentiation from nontoxigenic strains.

  6. Occurrence of Aspergillus section Flavi and aflatoxins in Brazilian rice: From field to market.

    Science.gov (United States)

    Katsurayama, Aline M; Martins, Ligia M; Iamanaka, Beatriz T; Fungaro, Maria Helena P; Silva, Josué J; Frisvad, Jens C; Pitt, John I; Taniwaki, Marta H

    2018-02-02

    The guarantee of the high quality of rice is of utmost importance because any toxic contaminant may affect consumer health, especially in countries such as Brazil where rice is part of the daily diet. A total of 187 rice samples, from field, processing and market from two different production systems, wetland from the state of Rio Grande do Sul, dryland, from the state of Maranhão and market samples from the state of São Paulo, were analyzed for fungi belonging to Aspergillus section Flavi and the presence of aflatoxins. Twenty-three soil samples from wetland and dryland were also analyzed. A total of 383 Aspergillus section Flavi strains were isolated from rice and soil samples. Using a polyphasic approach, with phenotypic (morphology and extrolite profiles) and molecular data (beta-tubulin gene sequences), five species were identified: A. flavus, A. caelatus, A. novoparasiticus, A. arachidicola and A. pseudocaelatus. This is the first report of these last three species from rice and rice plantation soil. Only seven (17%) of the A. flavus isolates produced type B aflatoxins, but 95% produced kojic acid and 69% cyclopiazonic acid. Less than 14% of the rice samples were contaminated with aflatoxins, but two of the market samples were well above the maximum tolerable limit (5μg/kg), established by the Brazilian National Health Surveillance Agency. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Selection of tannase-producing Aspergillus niger strains

    OpenAIRE

    Pinto,Gustavo A.S.; Leite,Selma G.F.; Terzi,Selma C.; Couri,Sonia

    2001-01-01

    The aim of this work was to select strains of Aspergillus niger for tannase production. Growth of colonies in plates with tannic acid-containing medium indicated their ability to synthesize tannase. Tannase activity was also measured in solid-state fermentation. A. niger 11T25A5 was the best tannase producer (67.5 U.g-1/72 hours of fermentation).

  8. Chromosomal duplication strains of Aspergillus nidulans and their instability

    International Nuclear Information System (INIS)

    Azevedo, J.L. de; Almeida Okino, L.M. de

    1981-01-01

    Strains of Aspergillus nidulans with chromosomal duplication were obtained after gamma irradiation followed by crossing of the translocated strains with normal strains. From 20 analysed colonies, 12 have shown translocations induced by irradiation. Segregants from four of these translocation strains crossed to normal strains have shown to be unstable although presenting normal morphology. Two segregants were genetically analysed. The first one has shown a duplication of part of linkage groups VIII and the second one presented a duplication of a segment of linkage group V. These new duplication strains in A. nidulans open new perspectives of a more detailed study of the instability phenomenon in this fungus. (Author) [pt

  9. Physiological characterisation of recombinant Aspergillus nidulans strains with different creA genotypes expressing A-oryzae alpha-amylase

    DEFF Research Database (Denmark)

    Agger, Teit; Petersen, J.B.; O'Connor, S.M.

    2002-01-01

    The physiology of three strains of Aspergillus nidulans was examined-a creA deletion strain, a wild type creA genotype and a strain containing extra copies of the creA gene, all producing Aspergillus oryzae alpha-amylase. The strains were cultured in batch and continuous cultivations and the biom......The physiology of three strains of Aspergillus nidulans was examined-a creA deletion strain, a wild type creA genotype and a strain containing extra copies of the creA gene, all producing Aspergillus oryzae alpha-amylase. The strains were cultured in batch and continuous cultivations...... and the biomass formation and alpha-amylase production was characterised. Overexpression of the creA gene resulted in a lower maximum specific growth rate and a slightly higher repression of the alpha-amylase production during conditions with high glucose concentration. No expression of creA also resulted...... in a decreased maximum specific growth rate, but also in drastic changes in morphology. Furthermore, the expression of alpha-amylase was completely derepressed and creA thus seems to be the only regulatory protein responsible for glucose repression of alpha-amylase expression. The effect of different carbon...

  10. Fumonisin and Ochratoxin Production in Industrial Aspergillus niger Strains

    Science.gov (United States)

    Frisvad, Jens C.; Larsen, Thomas O.; Thrane, Ulf; Meijer, Martin; Varga, Janos; Samson, Robert A.; Nielsen, Kristian F.

    2011-01-01

    Aspergillus niger is perhaps the most important fungus used in biotechnology, and is also one of the most commonly encountered fungi contaminating foods and feedstuffs, and occurring in soil and indoor environments. Many of its industrial applications have been given GRAS status (generally regarded as safe). However, A. niger has the potential to produce two groups of potentially carcinogenic mycotoxins: fumonisins and ochratoxins. In this study all available industrial and many non-industrial strains of A. niger (180 strains) as well as 228 strains from 17 related black Aspergillus species were examined for mycotoxin production. None of the related 17 species of black Aspergilli produced fumonisins. Fumonisins (B2, B4, and B6) were detected in 81% of A. niger, and ochratoxin A in 17%, while 10% of the strains produced both mycotoxins. Among the industrial strains the same ratios were 83%, 33% and 26% respectively. Some of the most frequently used strains in industry NRRL 337, 3112 and 3122 produced both toxins and several strains used for citric acid production were among the best producers of fumonisins in pure agar culture. Most strains used for other biotechnological processes also produced fumonisins. Strains optimized through random mutagenesis usually maintained their mycotoxin production capability. Toxigenic strains were also able to produce the toxins on media suggested for citric acid production with most of the toxins found in the biomass, thereby questioning the use of the remaining biomass as animal feed. In conclusion it is recommended to use strains of A. niger with inactive or inactivated gene clusters for fumonisins and ochratoxins, or to choose isolates for biotechnological uses in related non-toxigenic species such as A. tubingensis, A. brasiliensis, A vadensis or A. acidus, which neither produce fumonisins nor ochratoxins. PMID:21853139

  11. Aflatoxin B1 producing potential of Aspergillus flavus strains isolated ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-07-20

    Jul 20, 2009 ... consumption of aflatoxin contaminated food and feed. (Reddy and ..... intervals by artificial inoculation of A. parasiticus on rice grains. ... additive for culture media for rapid identification of aflatoxin producing. Aspergillus strains ...

  12. Effect of Aspergillus versicolor strain JASS1 on low density polyethylene degradation

    Science.gov (United States)

    Gajendiran, A.; Subramani, S.; Abraham, J.

    2017-11-01

    Low density polyethylene (LDPE) waste disposal remains one of the major environmental concerns faced by the world today. In past decades, major focus has been given to enhance the biodegradation of LDPE by microbial species. In this present study, Aspergillus versicolor with the ability to degrade LDPE was isolated from municipal landfill area using enrichment technique. Based on 18S rRNA gene sequencing confirmed its identity as Aspergillus versicolor. The biodegradation study was carried out for 90 d in M1 medium. The degradation behaviour of LDPE films by Aspergillus versicolor strain JASS1 were confirmed by weight loss, CO2 evolution, Scanning electron microscopy (SEM) analysis, Atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) technique. From current investigation, it can be concluded that our isolated strain JASS1 had the potential to degrade LDPE films and it can be useful in solving the problem caused by polyethylene in the environment.

  13. Fumonisin and Ochratoxin Production in Industrial Aspergillus niger Strains

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian; Larsen, Thomas Ostenfeld; Thrane, Ulf

    2011-01-01

    as safe). However, A. niger has the potential to produce two groups of potentially carcinogenic mycotoxins: fumonisins and ochratoxins. In this study all available industrial and many non-industrial strains of A. niger (180 strains) as well as 228 strains from 17 related black Aspergillus species were...... examined for mycotoxin production. None of the related 17 species of black Aspergilli produced fumonisins. Fumonisins (B(2), B(4), and B(6)) were detected in 81% of A. niger, and ochratoxin A in 17%, while 10% of the strains produced both mycotoxins. Among the industrial strains the same ratios were 83......%, 33% and 26% respectively. Some of the most frequently used strains in industry NRRL 337, 3112 and 3122 produced both toxins and several strains used for citric acid production were among the best producers of fumonisins in pure agar culture. Most strains used for other biotechnological processes also...

  14. Screening a strain of Aspergillus niger and optimization of fermentation conditions for degradation of aflatoxin B₁.

    Science.gov (United States)

    Zhang, Wei; Xue, Beibei; Li, Mengmeng; Mu, Yang; Chen, Zhihui; Li, Jianping; Shan, Anshan

    2014-11-13

    Aflatoxin B₁, a type of highly toxic mycotoxin produced by some species belonging to the Aspergillus genus, such as Aspergillus flavus and Aspergillus parasiticus, is widely distributed in feed matrices. Here, coumarin was used as the sole carbon source to screen microorganism strains that were isolated from types of feed ingredients. Only one isolate (ND-1) was able to degrade aflatoxin B₁ after screening. ND-1 isolate, identified as a strain of Aspergillus niger using phylogenetic analysis on the basis of 18S rDNA, could remove 26.3% of aflatoxin B₁ after 48 h of fermentation in nutrient broth (NB). Optimization of fermentation conditions for aflatoxin B₁ degradation by selected Aspergillus niger was also performed. These results showed that 58.2% of aflatoxin B₁ was degraded after 24 h of culture under the optimal fermentation conditions. The aflatoxin B₁ degradation activity of Aspergillus niger supernatant was significantly stronger than cells and cell extracts. Furthermore, effects of temperature, heat treatment, pH, and metal ions on aflatoxin B₁ degradation by the supernatant were examined. Results indicated that aflatoxin B₁ degradation of Aspergillus niger is enzymatic and this process occurs in the extracellular environment.

  15. Biotechnological conversion of waste cooking olive oil into lipid-rich biomass using Aspergillus and Penicillium strains.

    Science.gov (United States)

    Papanikolaou, S; Dimou, A; Fakas, S; Diamantopoulou, P; Philippoussis, A; Galiotou-Panayotou, M; Aggelis, G

    2011-05-01

    In this study, we have investigated the biochemical behaviour of Aspergillus sp. (five strains) and Penicillium expansum (one strain) fungi cultivated on waste cooking olive oil. The production of lipid-rich biomass was the main target of the work. In parallel, the biosynthesis of other extracellular metabolites (organic acids) and enzyme (lipase) and the substrate fatty acid specificity of the strains were studied. Carbon-limited cultures were performed on waste oil, added in the growth medium at 15g l(-1) , and high biomass quantities were produced (up to c.18g l(-1) , conversion yield of c. 1·0 g of dry biomass formed per g of fat consumed or higher). Cellular lipids were accumulated in notable quantities in almost all cultures. Aspergillus sp. ATHUM 3482 accumulated lipid up to 64·0% (w/w) in dry fungal mass. In parallel, extracellular lipase activity was quantified, and it was revealed to be strain and fermentation time dependent, with a maximum quantity of 645 U ml(-1) being obtained by Aspergillus niger NRRL 363. Storage lipid content significantly decreased at the stationary growth phase. Some differences in the fatty acid composition of both cellular and residual lipids when compared with the initial substrate fat used were observed; in various cases, cellular lipids more saturated and enriched with arachidic acid were produced. Aspergillus strains produced oxalic acid up to 5·0 g l(-1) . Aspergillus and Penicillium strains are able to convert waste cooking olive oil into high-added-value products.   Increasing fatty wastes amounts are annually produced. The current study provided an alternative way of biovalourization of these materials, by using them as substrates, to produce added-value compounds. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

  16. Nonfunctionality of Aspergillus sojae aflR in a strain of Aspergillus parasiticus with a disrupted aflR gene.

    Science.gov (United States)

    Takahashi, Tadashi; Chang, Perng-Kuang; Matsushima, Kenichiro; Yu, Jiujiang; Abe, Keietsu; Bhatnagar, Deepak; Cleveland, Thomas E; Koyama, Yasuji

    2002-08-01

    Aspergillus sojae belongs to the Aspergillus section Flavi but does not produce aflatoxins. The functionality of the A. sojae aflR gene (aflRs) was examined by transforming it into an DeltaaflR strain of A. parasiticus, derived from a nitrate-nonutilizing, versicolorin A (VERA)-accumulating strain. The A. parasiticus aflR gene (aflRp) transformants produced VERA, but the aflRs transformants did not. Even when aflRs was placed under the control of the amylase gene (amyB) promoter of Aspergillus oryzae, the amy(p)::aflRs transformants did not produce VERA. A chimeric construct containing the aflRs promoter plus the aflRs N- and aflRp C-terminal coding regions could restore VERA production, but a construct containing the aflRp promoter plus the aflRp N- and aflRs C-terminal coding regions could not. These results show that the A. sojae aflR promoter is functional in A. parasiticus and that the HAHA motif does not affect the function of the resulting hybrid AflR. We conclude that the lack of aflatoxin production by A. sojae can be attributed, at least partially, to the premature termination defect in aflRs, which deletes the C-terminal transcription activation domain that is critical for the expression of aflatoxin biosynthetic genes.

  17. Genome sequences of three strains of Aspergillus flavus for the biological control of Aflatoxin

    Science.gov (United States)

    The genomes of three strains of Aspergillus flavus with demonstrated utility for the biological control of aflatoxin were sequenced. These sequences were assembled with MIRA and annotated with Augustus using A. flavus strain 3357 (NCBI EQ963472) as a reference. Each strain had a genome of 36.3 to ...

  18. Two new aflatoxin producing species, and an overview of Aspergillus section Flavi

    Science.gov (United States)

    Varga, J.; Frisvad, J.C.; Samson, R.A.

    2011-01-01

    Aspergillus subgenus Circumdati section Flavi includes species with usually biseriate conidial heads, in shades of yellow-green to brown, and dark sclerotia. Several species assigned to this section are either important mycotoxin producers including aflatoxins, cyclopiazonic acid, ochratoxins and kojic acid, or are used in oriental food fermentation processes and as hosts for heterologous gene expression. A polyphasic approach was applied using morphological characters, extrolite data and partial calmodulin, β-tubulin and ITS sequences to examine the evolutionary relationships within this section. The data indicate that Aspergillus section Flavi involves 22 species, which can be grouped into seven clades. Two new species, A. pseudocaelatus sp. nov. and A. pseudonomius sp. nov. have been discovered, and can be distinguished from other species in this section based on sequence data and extrolite profiles. Aspergillus pseudocaelatus is represented by a single isolate collected from Arachis burkartii leaf in Argentina, is closely related to the non-aflatoxin producing A. caelatus, and produces aflatoxins B & G, cyclopiazonic acid and kojic acid, while A. pseudonomius was isolated from insects and soil in the USA. This species is related to A. nomius, and produces aflatoxin B1 (but not G-type aflatoxins), chrysogine and kojic acid. In order to prove the aflatoxin producing abilities of the isolates, phylogenetic analysis of three genes taking part in aflatoxin biosynthesis, including the transcriptional regulator aflR, norsolonic acid reductase and O-methyltransferase were also carried out. A detailed overview of the species accepted in Aspergillus section Flavi is presented. PMID:21892243

  19. Lipase production by recombinant strains of Aspergillus niger expressing a lipase-encoding gene from Thermomyces lanuginosus

    DEFF Research Database (Denmark)

    Prathumpai, Wai; Flitter, S.J.; Mcintyre, Mhairi

    2004-01-01

    Two recombinant strains of Aspergillus niger (NW 297-14 and NW297-24) producing a heterologous lipase from Thermomyces lanuginosus were constructed. The heterologous lipase was expressed using the TAKA amylase promoter from Aspergillus oryzae. The production kinetics of the two strains on different...... shows that it is possible to obtain high productivities of heterologous fungal enzymes in A. niger. However, SDS-PAGE analysis showed that most of the produced lipase was bound to the cell wall....

  20. Differential impact of some Aspergillus species on Meloidogyne javanica biocontrol by Pseudomonas fluorescens strain CHA0.

    Science.gov (United States)

    Siddiqui, I A; Shaukat, S S; Khan, A

    2004-01-01

    The aim was to determine the influence of some Aspergillus species on the production of nematicidal agent(s) in vitro and biocontrol of Meloidogyne javanica in tomato by Pseudomonas fluorescens strains CHA0 and CHA0/pME3424. Six species of Aspergillus, isolated from the rhizosphere of certain crops, produced a variety of secondary metabolites in vitro. Culture filtrate (CF) obtained from Ps. fluorescens strain CHA0 and its2,4-diacetylphloroglucinol overproducing mutant CHA0/pME3424 grown in King's B liquid medium caused significant mortality of M. javanica juveniles in vitro. Bacterial growth medium amended with CF of A. niger enhanced nematicidal and beta-galactosidase activities of fluorescent pseudomonads while A. quadrilineatus repressed such activities. Methanol or ethyl acetate extracts of the CF of A. niger markedly optimized bacterial efficacy to cause nematode deaths while hexane extract of the fungus had no influence on the nematicidal activity of the bacterial strains. A. niger applied alone or in conjunction with the bacterial inoculants inhibited root-knot nematode galling in tomato. On the other hand, A. quadrilineatus used alone or together with CHA0 did not inhibit nematode galling but when used in combination with strain CHA0/pME3424 did reduce galling intensity. Aspergillus niger enhances the production of nematicidal compounds by Ps. fluorescensin vitro and improves biocontrol potential of the bacterial inoculants in tomato while A. quadrilineatus reduces bacterial performance to suppress root-knot nematodes. Rhizosphere harbours a variety of micro-organisms including bacteria, fungi and viruses. Aspergillus species are ubiquitous in most agricultural soils and generally produce a variety of secondary metabolites. Such metabolites synthesized by Aspergillus species may influence the production of nematicidal agents and subsequent biocontrol performance of the bacterial inoculants against plant-parasitic nematodes. This fact needs to be taken into

  1. Aspergillus asper sp. nov. and Aspergillus collinsii sp. nov., from Aspergillus section Usti.

    Science.gov (United States)

    Jurjevic, Zeljko; Peterson, Stephen W

    2016-07-01

    In sampling fungi from the built environment, two isolates that could not confidently be placed in described species were encountered. Phenotypic analysis suggested that they belonged in Aspergillus sect. Usti. In order to verify the sectional placement and to assure that they were undescribed rather than phenotypically aberrant isolates, DNA was isolated and sequenced at the beta-tubulin, calmodulin, internal transcribed spacer and RNA polymerase II loci and sequences compared with those from other species in the genus Aspergillus. At each locus, each new isolate was distant from existing species. Phylogenetic trees calculated from these data and GenBank data for species of the section Usti excluded the placement of these isolates in existing species, with statistical support. Because they were excluded from existing taxa, the distinct species Aspergillus asper (type strain NRRL 35910 T ) and Aspergillus collinsii (type strain NRRL 66196 T ) in sect. Usti are proposed to accommodate these strains.

  2. Ochratoxin A production by strains of Aspergillus niger var. niger.

    Science.gov (United States)

    Abarca, M L; Bragulat, M R; Castellá, G; Cabañes, F J

    1994-01-01

    In a survey of the occurrence of ochratoxin A (OA)-positive strains isolated from feedstuffs, two of the 19 isolates of Aspergillus niger var. niger that were studied produced OA in 2% yeast extract-15% sucrose broth and in corn cultures. This is the first report of production of OA by this species. PMID:8074536

  3. Achieving mutations of glycogenic strain Aspergillus awamori using ultraviolet radiation

    International Nuclear Information System (INIS)

    Rykala-Ziobro, M.; Dluzniewska, J.; Jedrzejowska, A.

    1994-01-01

    It was attempted to increase glucoamylase productivity of strain Aspergillus awamori, using UV light as a mutagenic agent. To this end, the conidias were twice irradiated, what resulted in obtaining the mutant with about 27% higher glucoamylase activity followed first irradiation of the conidias. Mutant form did not differ morphologically from the initial material (author)

  4. Morphological characterization of recombinant strains of Aspergillus oryzae producing alpha-amylase during batch cultivations

    DEFF Research Database (Denmark)

    Spohr, Anders Bendsen; Carlsen, Morten; Nielsen, Jens Bredal

    1997-01-01

    Three alpha-amylase producing strains of Aspergillus oryzae used for recombinant protein production have been studied with respect to growth and protein production. By comparing the three strains with respect to morphology and protein production it is shown that a morphological mutant with a more...

  5. Comparative Genome Analysis Between Aspergillus oryzae Strains Reveals Close Relationship Between Sites of Mutation Localization and Regions of Highly Divergent Genes among Aspergillus Species

    Science.gov (United States)

    Umemura, Myco; Koike, Hideaki; Yamane, Noriko; Koyama, Yoshinori; Satou, Yuki; Kikuzato, Ikuya; Teruya, Morimi; Tsukahara, Masatoshi; Imada, Yumi; Wachi, Youji; Miwa, Yukino; Yano, Shuichi; Tamano, Koichi; Kawarabayasi, Yutaka; Fujimori, Kazuhiro E.; Machida, Masayuki; Hirano, Takashi

    2012-01-01

    Aspergillus oryzae has been utilized for over 1000 years in Japan for the production of various traditional foods, and a large number of A. oryzae strains have been isolated and/or selected for the effective fermentation of food ingredients. Characteristics of genetic alterations among the strains used are of particular interest in studies of A. oryzae. Here, we have sequenced the whole genome of an industrial fungal isolate, A. oryzae RIB326, by using a next-generation sequencing system and compared the data with those of A. oryzae RIB40, a wild-type strain sequenced in 2005. The aim of this study was to evaluate the mutation pressure on the non-syntenic blocks (NSBs) of the genome, which were previously identified through comparative genomic analysis of A. oryzae, Aspergillus fumigatus, and Aspergillus nidulans. We found that genes within the NSBs of RIB326 accumulate mutations more frequently than those within the SBs, regardless of their distance from the telomeres or of their expression level. Our findings suggest that the high mutation frequency of NSBs might contribute to maintaining the diversity of the A. oryzae genome. PMID:22912434

  6. Comparative genome analysis between Aspergillus oryzae strains reveals close relationship between sites of mutation localization and regions of highly divergent genes among Aspergillus species.

    Science.gov (United States)

    Umemura, Myco; Koike, Hideaki; Yamane, Noriko; Koyama, Yoshinori; Satou, Yuki; Kikuzato, Ikuya; Teruya, Morimi; Tsukahara, Masatoshi; Imada, Yumi; Wachi, Youji; Miwa, Yukino; Yano, Shuichi; Tamano, Koichi; Kawarabayasi, Yutaka; Fujimori, Kazuhiro E; Machida, Masayuki; Hirano, Takashi

    2012-10-01

    Aspergillus oryzae has been utilized for over 1000 years in Japan for the production of various traditional foods, and a large number of A. oryzae strains have been isolated and/or selected for the effective fermentation of food ingredients. Characteristics of genetic alterations among the strains used are of particular interest in studies of A. oryzae. Here, we have sequenced the whole genome of an industrial fungal isolate, A. oryzae RIB326, by using a next-generation sequencing system and compared the data with those of A. oryzae RIB40, a wild-type strain sequenced in 2005. The aim of this study was to evaluate the mutation pressure on the non-syntenic blocks (NSBs) of the genome, which were previously identified through comparative genomic analysis of A. oryzae, Aspergillus fumigatus, and Aspergillus nidulans. We found that genes within the NSBs of RIB326 accumulate mutations more frequently than those within the SBs, regardless of their distance from the telomeres or of their expression level. Our findings suggest that the high mutation frequency of NSBs might contribute to maintaining the diversity of the A. oryzae genome.

  7. Antifungal activity of some marine organisms from India, against food spoilage Aspergillus strains

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosale, S.H.; Jagtap, T.G.; Naik, C.G.

    Crude aqueous methanol extracts obtained from 31 species of various marine organisms (including floral and faunal), were screened for their antifungal activity against food poisoning strains of Aspergillus. Seventeen species exhibited mild (+ = zone...

  8. Characterization of metabolites from a strain of Aspergillus flavus accumulating aflatoxin B2

    International Nuclear Information System (INIS)

    Dutton, M.F.

    1985-01-01

    A number of aflatoxins and anthraquinone pigments were isolated from a strain of Aspergillus flavus, several of which were fully characterized. The major metabolites isolated were aflatoxin B 2 and versicolorin C, which are normally only found as minor products from species of the genus Aspergillus. The identification of these products supports the proposal that aflatoxin B 2 can arise independently of aflatoxin B 1 and that, in this case, the branch in the pathway occurs at the versicolorins. Other metabolites charaterized were aflatoxin M 2 , norsolorinic acid, and averufin

  9. Evaluation of the atoxigenic Aspergillus flavus strain AF36 in pistachio orchards

    Science.gov (United States)

    The atoxigenic strain Aspergillus flavus AF36, which has been extensively used as a biocontrol agent in commercial corn and cotton fields to reduce aflatoxin contamination, was applied in research pistachio orchards from 2002 to 2005 and in commercial pistachio orchards from 2008 to 2011. AF36 was a...

  10. Study of itaconic acid production by Aspergillus terrus MJL05 strain with different variable

    OpenAIRE

    Mariana Juy; Joaquín Orejas; María Ester Lucca

    2010-01-01

    Título en español: Estudio de la producción de ácido itacónico con Aspergillus terreus de la cepa MJL05 con diferentes variables Abstract Itaconic acid (IA) production by Aspergillus terreus MJL05 strain was investigated in submerged batch fermentation in a stirred bioreactor to determine the effect of varying the nitrogen, phosphorous and carbon sources concentrations in the production medium. Glycerol, a biodiesel by-product was reported as an efficient substrate to achieve high ita...

  11. Study of itaconic acid production by aspergillus terrus mjl05 strain with different variable

    OpenAIRE

    Juy, Mariana; Orejas, Joaquín; Lucca, María Ester

    2010-01-01

    Título en español: Estudio de la producción de ácido itacónico con Aspergillus terreus de la cepa MJL05 con diferentes variables Abstract Itaconic acid (IA) production by Aspergillus terreus MJL05 strain was investigated in submerged batch fermentation in a stirred bioreactor to determine the effect of varying the nitrogen, phosphorous and carbon sources concentrations in the production medium. Glycerol, a biodiesel by-product was reported as an efficient substrate to achieve high ita...

  12. Identification and toxigenic potential of the industrially important fungi, Aspergillus oryzae and Aspergillus sojae

    DEFF Research Database (Denmark)

    Jørgensen, Thomas R

    2007-01-01

    Mold strains belonging to the species Aspergillus oryzae and Aspergillus sojae are highly valued as koji molds in the traditional preparation of fermented foods, such as miso, sake, and shoyu, and as protein production hosts in modern industrial processes. A. oryzae and A. sojae are relatives...... of the wild molds Aspergillus flavus and Aspergillus parasiticus. All four species are classified to the A. flavus group. Strains of the A. flavus group are characterized by a high degree of morphological similarity. Koji mold species are generally perceived of as being nontoxigenic, whereas wild molds...... are associated with the carcinogenic aflatoxins. Thus, reliable identification of individual strains is very important for application purposes. This review considers the pheno- and genotypic markers used in the classification of A. flavus group strains and specifically in the identification of A. oryzae and A...

  13. Methyl Red Decolorization Efficiency of a Korea Strain of Aspergillus sp. Immobilized into Different Polymeric Matrices.

    Science.gov (United States)

    Kim, Beom-Su; Blaghen, Mohamed; Lee, Kang-Min

    2017-07-01

      Intensive research studies have revealed that fungal decolorization of dye wastewater is a promising replacement for the current process of dye wastewater decolorization. The authors isolated an Aspergillus sp. from the effluent of a textile industry area in Korea and assessed the effects of a variety of operational parameters on the decolorization of methyl red (MR) by this strain of Aspergillus sp. This Aspergillus sp. was then immobilized by entrapment in several polymeric matrices and the effects of operational conditions on MR decolorization were investigated again. The optimal decolorization activity of this Aspergillus sp. was observed in 1% glucose at a temperature of 37 °C and pH of 6.0. Furthermore, stable decolorization efficiency was observed when fungal biomass was immobilized into alginate gel during repeated batch experiment. These results suggest that the Aspergillus sp. isolated in Korea could be used to treat industrial wastewaters containing MR dye.

  14. Aspergillus saccharolyticus sp. nov., a new black Aspergillus species isolated in Denmark

    DEFF Research Database (Denmark)

    Sørensen, Annette; Lübeck, Peter S.; Lübeck, Mette

    2011-01-01

    A novel species, Aspergillus saccharolyticus sp. nov., belonging to the Aspergillus section Nigri group is described. This species was isolated in Denmark from treated hardwood. Its taxonomic status was determined using a polyphasic taxonomic approach including phenotypic (morphology and extrolite...... Aspergillus species that is morphologically similar to Aspergillus japonicus and Aspergillus aculeatus, but has a totally different extrolite profile compared to any known Aspergillus species. The type strain of A. saccharolyticus sp. nov. is CBS 127449T ( = IBT 28509T)....

  15. Relationship of Quantity of Citric Acid and Protein Content of Mycelia during Citric Acid Production by Three Strains of Aspergillus niger

    International Nuclear Information System (INIS)

    Abdullah-Al-Mahin; Alamgir Z. Chowdhury; Rehana Begum

    2006-01-01

    The amount of protein in the surface grown mycelia of three strains of Aspergillus niger (CA16,79/20 and 318) was found to decrease with the increase of citric acid production in sucrose based fermentation medium. Throughout the study period of 6 to 10 days of fermentation, highest amount of citric acid was produced by Aspergillus niger 318 although the amount of protein in mycelia was lowest for this strain. On the other hand, lowest amount of citric acid was produced by the strain CA 16 which in tern produced highest amount of mycelial protein. Aspergillus niger 79/20 produced both intermediate level of protein and citric acid. The Protein was estimated by three commonly used methods namely: Kjeldahl, Biuret and Lowry methods. Kjeldahl and Lowry method gave the highest and lowest results respectively for protein determination in all cases.(authors)

  16. Selection of tannase-producing Aspergillus niger strains Seleção de linhagens de Aspergillus niger produtoras de tanase

    Directory of Open Access Journals (Sweden)

    Gustavo A.S. Pinto

    2001-03-01

    Full Text Available The aim of this work was to select strains of Aspergillus niger for tannase production. Growth of colonies in plates with tannic acid-containing medium indicated their ability to synthesize tannase. Tannase activity was also measured in solid-state fermentation. A. niger 11T25A5 was the best tannase producer (67.5 U.g-1/72 hours of fermentation.O objetivo deste trabalho foi selecionar linhagens de Aspergillus niger para síntese de tanase. O crescimento das colônias em meio contendo ácido tânico indicou capacidade de produção de tanase. A atividade enzimática foi determinada em fermentação semi-sólida. A. niger 11T25A5 foi o melhor produtor (67.5 U.g-1/72 horas de fermentação.

  17. Non-aflatoxigenicity of commercial Aspergillus oryzae strains due to genetic defects compared to aflatoxigenic Aspergillus flavus.

    Science.gov (United States)

    Tao, Lin; Chung, Soo Hyun

    2014-08-01

    Aspergillus oryzae is generally recognized as safe, but it is closely related to A. flavus in morphology and genetic characteristics. In this study, we tested the aflatoxigenicity and genetic analysis of nine commercial A. oryzae strains that were used in Korean soybean fermented products. Cultural and HPLC analyses showed that none of the commercial strains produced detectable amount of aflatoxins. According to the molecular analysis of 17 genes in the aflatoxin (AF) biosynthetic pathway, the commercial strains could be classified into three groups. The group I strains contained all the 17 AF biosynthetic genes tested in this study; the group II strains deleted nine AF biosynthetic genes and possessed eight genes, including aflG, aflI, aflK, aflL, aflM, aflO, aflP, and aflQ; the group III strains only had six AF biosynthetic genes, including aflG, aflI, aflK, aflO, aflP, and aflQ. With the reverse transcription polymerase chain reaction, the group I A. oryzae strains showed no expression of aflG, aflQ and/or aflM genes, which resulted in the lack of AF-producing ability. Group II and group III strains could not produce AF owing to the deletion of more than half of the AF biosynthetic genes. In addition, the sequence data of polyketide synthase A (pksA) of group I strains of A. oryzae showed that there were three point mutations (two silent mutations and one missense mutation) compared with aflatoxigenic A. flavus used as the positive control in this study.

  18. Efficiency of four currently used decontamination conditionings in Romania against Aspergillus and Candida strains.

    Science.gov (United States)

    Lorin, D; Cristina, R T; Teusdea, V; Mitrănescu, E; Muselin, F; Butnariu, M; David, G; Dumitrescu, E

    2017-09-01

    Efficacy of four commercial biocidal products (noted A to D), using manufacturers' recommendations, and a contact time of 30minutes, were evaluated in the purpose of standard SR EN1657: 2006 adapted. Were used four strains, two as reference: Aspergillus brasiliensis (niger) (ATCC 16404) and Candida albicans (ATCC 10231), and two isolates: Aspergillus flavus and respectively Aspergillus fumigatus. The inoculum plates containing Malt Extract Agar (MEA) were incubated 48h for C. albicans and 72hours for Aspergillus spp. The standard SR EN1657: 2006 adapted was conducted in two phases: the test cultures preparation and the method validation. Method validation included: the control of experimental conditions and of neutralizant solution, and the method verification. Results revealed that three from the four tested products (A, B and D) had exerted biocidal effect on the studied strains at the recommended concentrations, the registered CFU values being reduced by more than 4 log 10 , conversely in the case of the product (C), applied against A. fumigatus at the recommended concentration of 2%, the biocidal effect was not detected, fact confirmed also by the CFU's value (3.59 log 10 ). The biocide retested at a greater concentration (of 5%), showed a biocidal effect against A. fumigatus after 30minutes, the CFU value being reduced, by more than 5.29 log 10 , evidencing the resistance emergence of A. fumigatus under the repeated pressure of biocides. It is re-confirming that merely the "chemical" defense measures to defuse the fungi's strategies become unproductive. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  19. A survey of xerophilic Aspergillus from indoor environment, including descriptions of two new section Aspergillus species producing eurotium-like sexual states

    DEFF Research Database (Denmark)

    Visagie, Cobus M.; Yilmaz, Neriman; Renaud, Justin B.

    2017-01-01

    of 1039 strains; 296 strains belong to Aspergillus and represented 37 species. Reference sequences were generated for all species and deposited in GenBank. Aspergillus sect. Aspergillus (formerly called Eurotium) was one of the most predominant groups from house dust with nine species identified...

  20. Improvement of xylanase production by a parasexual cross between Aspergillus niger strains

    Directory of Open Access Journals (Sweden)

    Octavio Loera

    2003-03-01

    Full Text Available A diploid strain (D4 isolated via parasexual recombination between two Aspergillus niger xylanase overproducing mutants was characterised in terms of enzyme production and catabolite repression by glucose. This strain increased xylanase production (607 nkat/ml, which was nearly 100% higher than titers achieved by the wild type strain (305 nkat/ml and 28% higher than the best mutant used to induce parasexual cycle. Diploid D4 was also less sensitive to carbon catabolite repression by glucose, since xylanolytic activity was detected under conditions normally repressing production by the wild type strain. No decrease in maximal xylanase levels was observed in the presence of glucose for diploid D4.Um cepa diplóide (D4 isolada por combinação parasexual entre dois Aspergillus niger, mutantes superprodutores de xylanase foi caracterizado através da produção de (607 nkat/ml e repressão catabólica por glicose. Essa cepa aumenta a produção de xylanase em mais de 100% em comparação com uma cepa selvagem (305 nkat/ml e 28% superior do que o melhor mutante usado para induzir o ciclo parasexual. A cepa diplóide D4 foi também menos sensível a repressão catabólica pela glicose, sendo que a atividade xylanolitica foi detectada sob condições normalmente de produção repressiva pela cepa selvagem. Não foi observado um decréscimo na produção máxima de xylanase em presença de glicose para o diplóide D4.

  1. Identification of enzymes and quantification of metabolic fluxes in the wild type and in a recombinant Aspergillus oryzae strain

    DEFF Research Database (Denmark)

    Pedersen, Henrik; Carlsen, Morten; Nielsen, Jens Bredal

    1999-01-01

    Two alpha-amylase-producing strains of Aspergillus oryzae, a wild-type strain and a recombinant containing additional copies of the alpha-amylase gene, were characterized,vith respect to enzyme activities, localization of enzymes to the mitochondria or cytosol, macromolecular composition...

  2. Identification of thermostable β-xylosidase activities produced by Aspergillus brasiliensis and Aspergillus niger

    DEFF Research Database (Denmark)

    Pedersen, Mads; Lauritzen, Henrik Klitgaard; Frisvad, Jens Christian

    2007-01-01

    Twenty Aspergillus strains were evaluated for production of extracellular cellulolytic and xylanolytic activities. Aspergillus brasiliensis, A. niger and A. japonicus produced the highest xylanase activities with the A. brasiliensis and A. niger strains producing thermostable beta......-xylosidases. The beta-xylosidase activities of the A. brasiliensis and A. niger strains had similar temperature and pH optima at 75 degrees C and pH 5 and retained 62% and 99%, respectively, of these activities over 1 h at 60 degrees C. At 75 degrees C, these values were 38 and 44%, respectively. Whereas A. niger...

  3. Identification and toxigenic potential of the industrially important fungi, Aspergillus oryzae and Aspergillus sojae.

    Science.gov (United States)

    Jørgensen, Thomas R

    2007-12-01

    Mold strains belonging to the species Aspergillus oryzae and Aspergillus sojae are highly valued as koji molds in the traditional preparation of fermented foods, such as miso, sake, and shoyu, and as protein production hosts in modern industrial processes. A. oryzae and A. sojae are relatives of the wild molds Aspergillus flavus and Aspergillus parasiticus. All four species are classified to the A. flavus group. Strains of the A. flavus group are characterized by a high degree of morphological similarity. Koji mold species are generally perceived of as being nontoxigenic, whereas wild molds are associated with the carcinogenic aflatoxins. Thus, reliable identification of individual strains is very important for application purposes. This review considers the pheno- and genotypic markers used in the classification of A. flavus group strains and specifically in the identification of A. oryzae and A. sojae strains. Separation of A. oryzae and A. sojae from A. flavus and A. parasiticus, respectively, is inconsistent, and both morphologic and molecular evidence support conspecificity. The high degree of identity is reflected by the divergent identification of reference cultures maintained in culture collections. As close relatives of aflatoxin-producing wild molds, koji molds possess an aflatoxin gene homolog cluster. Some strains identified as A. oryzae and A. sojae have been implicated in aflatoxin production. Identification of a strain as A. oryzae or A. sojae is no guarantee of its inability to produce aflatoxins or other toxic metabolites. Toxigenic potential must be determined specifically for individual strains. The species taxa, A. oryzae and A. sojae, are currently conserved by societal issues.

  4. Comparative Genome Analysis Between Aspergillus oryzae Strains Reveals Close Relationship Between Sites of Mutation Localization and Regions of Highly Divergent Genes among Aspergillus Species

    OpenAIRE

    Umemura, Myco; Koike, Hideaki; Yamane, Noriko; Koyama, Yoshinori; Satou, Yuki; Kikuzato, Ikuya; Teruya, Morimi; Tsukahara, Masatoshi; Imada, Yumi; Wachi, Youji; Miwa, Yukino; Yano, Shuichi; Tamano, Koichi; Kawarabayasi, Yutaka; Fujimori, Kazuhiro E.

    2012-01-01

    Aspergillus oryzae has been utilized for over 1000 years in Japan for the production of various traditional foods, and a large number of A. oryzae strains have been isolated and/or selected for the effective fermentation of food ingredients. Characteristics of genetic alterations among the strains used are of particular interest in studies of A. oryzae. Here, we have sequenced the whole genome of an industrial fungal isolate, A. oryzae RIB326, by using a next-generation sequencing system and ...

  5. Scientific Opinion on Lipase from a Genetically Modified Strain of Aspergillus oryzae (strain NZYM-LH)

    OpenAIRE

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF)

    2014-01-01

    The food enzyme considered in this opinion is a lipase (triacylglycerol lipase; EC 3.1.1.3) produced with a genetically modified strain of Aspergillus oryzae. The genetic modifications do not raise safety concern. The food enzyme contains neither the production organism nor recombinant DNA. The lipase is intended to be used in a number of food manufacturing processes, such as in baking and other cereal-based processes. The dietary exposure was assessed on the basis of data retrieved from the ...

  6. Comparative studies on production of cellulases from three strains of aspergillus niger

    International Nuclear Information System (INIS)

    Sohail, M.; Ahmad, A.; Khan, S.

    2014-01-01

    Three strains of Aspergillus niger were retrieved from culture collection of the Department of Microbiology, University of Karachi, Pakistan and were studied for their ability to produce cellulases. Cultivation at different temperatures and in presence of various carbon sources revealed that all the three strains produced more amounts of endoglucanase, glucosidase and filter-paperase activities at 35 degree C; carboxymethyl cellulose promotes the production of filter paperase and endoglucanase activities whereas salicin induced glucosidase activity. Experiments on growth and enzyme production kinetics showed that generation time and hence volumetric rate of biomass production is influenced by the carbon source used in the medium; simple carbon source, such as glucose favored the growth of all the strains. Cellulases from all the strains showed optimum activity at temperature >50 degree C and under acidic range of pH, while melting temperature was 64-65 degree C. These findings affirm that cellulases from A. niger are potential candidates as alternative to Trichoderma cellulases. (author)

  7. Evaluation of commercial soy sauce koji strains of Aspergillus oryzae for γ-aminobutyric acid (GABA) production.

    Science.gov (United States)

    Ab Kadir, Safuan; Wan-Mohtar, Wan Abd Al Qadr Imad; Mohammad, Rosfarizan; Abdul Halim Lim, Sarina; Sabo Mohammed, Abdulkarim; Saari, Nazamid

    2016-10-01

    In this study, four selected commercial strains of Aspergillus oryzae were collected from soy sauce koji. These A. oryzae strains designated as NSK, NSZ, NSJ and NST shared similar morphological characteristics with the reference strain (A. oryzae FRR 1675) which confirmed them as A. oryzae species. They were further evaluated for their ability to produce γ-aminobutyric acid (GABA) by cultivating the spore suspension in a broth medium containing 0.4 % (w/v) of glutamic acid as a substrate for GABA production. The results showed that these strains were capable of producing GABA; however, the concentrations differed significantly (P sauce production.

  8. Aspergillus tubingensis and Aspergillus niger as the dominant black Aspergillus, use of simple PCR-RFLP for preliminary differentiation.

    Science.gov (United States)

    Mirhendi, H; Zarei, F; Motamedi, M; Nouripour-Sisakht, S

    2016-03-01

    This work aimed to identify the species distribution of common clinical and environmental isolates of black Aspergilli based on simple restriction fragment length polymorphism (RFLP) analysis of the β-tubulin gene. A total of 149 clinical and environmental strains of black Aspergilli were collected and subjected to preliminary morphological examination. Total genomic DNAs were extracted, and PCR was performed to amplify part of the β-tubulin gene. At first, 52 randomly selected samples were species-delineated by sequence analysis. In order to distinguish the most common species, PCR amplicons of 117 black Aspergillus strains were identified by simple PCR-RFLP analysis using the enzyme TasI. Among 52 sequenced isolates, 28 were Aspergillus tubingensis, 21 Aspergillus niger, and the three remaining isolates included Aspergillus uvarum, Aspergillus awamori, and Aspergillus acidus. All 100 environmental and 17 BAL samples subjected to TasI-RFLP analysis of the β-tubulin gene, fell into two groups, consisting of about 59% (n=69) A. tubingensis and 41% (n=48) A. niger. Therefore, the method successfully and rapidly distinguished A. tubingensis and A. niger as the most common species among the clinical and environmental isolates. Although tardy, the Ehrlich test was also able to differentiate A. tubingensis and A. niger according to the yellow color reaction specific to A. niger. A. tubingensis and A. niger are the most common black Aspergillus in both clinical and environmental isolates in Iran. PCR-RFLP using TasI digestion of β-tubulin DNA enables rapid screening for these common species. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  9. Construction of a genetically modified wine yeast strain expressing the Aspergillus aculeatus rhaA gene, encoding an -L-Rhamnosidase of enological interest

    NARCIS (Netherlands)

    Manzanares, P.; Orejas, M.; Vicente Gil, J.; Graaff, de L.H.; Visser, J.; Ramon, D.

    2003-01-01

    The Aspergillus aculeatus rhaA gene encoding an alpha-L-rhamnosidase has been expressed in both laboratory and industrial wine yeast strains. Wines produced in microvinifications, conducted using a combination of the genetically modified industrial strain expressing rhaA and another strain

  10. Antifungal activity of terrestrial Streptomyces rochei strain HF391 against clinical azole -resistant Aspergillus fumigatus

    Science.gov (United States)

    Hadizadeh, S; Forootanfar, H; Shahidi Bonjar, GH; Falahati Nejad, M; Karamy Robati, A; Ayatollahi Mousavi, SA; Amirporrostami, S

    2015-01-01

    Background and Purpose: Actinomycetes have been discovered as source of antifungal compounds that are currently in clinical use. Invasive aspergillosis (IA) due to Aspergillus fumigatus has been identified as individual drug-resistant Aspergillus spp. to be an emerging pathogen opportunities a global scale. This paper described the antifungal activity of one terrestrial actinomycete against the clinically isolated azole-resistant A. fumigatus. Materials and Methods: Soil samples were collected from various locations of Kerman, Iran. Thereafter, the actinomycetes were isolated using starch-casein-nitrate-agar medium and the most efficient actinomycetes (capable of inhibiting A. fumigatus) were screened using agar block method. In the next step, the selected actinomycete was cultivated in starch-casein- broth medium and the inhibitory activity of the obtained culture broth was evaluated using agar well diffusion method. Results: The selected actinomycete, identified as Streptomyces rochei strain HF391, could suppress the growth of A. fumigatus isolates which was isolated from the clinical samples of patients treated with azoles. This strain showed higher inhibition zones on agar diffusion assay which was more than 15 mm. Conclusion: The obtained results of the present study introduced Streptomyces rochei strain HF391 as terrestrial actinomycete that can inhibit the growth of clinically isolated A. fumigatus. PMID:28680984

  11. Glucoamylase production in batch, chemostat and fed-batch cultivations by an industrial strain of Aspergillus niger

    DEFF Research Database (Denmark)

    Pedersen, Henrik; Beyer, Michael; Nielsen, Jens

    2000-01-01

    The Aspergillus niger strain BO-1 was grown in batch, continuous (chemostat) and fed-batch cultivations in order to study the production of the extracellular enzyme glucoamylase under different growth conditions. In the pH range 2.5-6.0, the specific glucoamylase productivity and the specific...

  12. Cyclopiazonic Acid Biosynthesis of Aspergillus flavus and Aspergillus oryzae

    Science.gov (United States)

    Cyclopiazonic acid (CPA) is an indole-tetramic acid neurotoxin produced by some of the same strains of A. flavus that produce aflatoxins and by some Aspergillus oryzae strains. Despite its discovery 40 years ago, few reviews of its toxicity and biosynthesis have been reported. This review examines w...

  13. Evaluation of recycled bioplastic pellets and a sprayable formulation for application of an Aspergillus flavus biocontrol strain

    Science.gov (United States)

    Biocontrol of Aspergillus flavus using inoculated bioplastic granules has been proven to be effective under laboratory and field conditions. In the present study, the use of low-density pellets from recycled bioplastic as a biocontrol strain carrier was evaluated. Applying recycled bioplastic pell...

  14. Studies on Aspergillus flavus

    International Nuclear Information System (INIS)

    Padwal-Desai, S.R.; Ghanekar, A.S.; Sreenivasan, A.

    1976-01-01

    In vitro studies were conducted on conidia of Aspergillus flavus Link (aflatoxin producing) and Aspergillus flavus oryzae (non-toxigenic) strains isolated and identified in this laboratory. These strains differed in resistance to heat and gamma radiation, the toxigenic strain being more resistant to both treatments. Results of tests on dose-modifying factors indicated that composition, temperature and pH of suspending media affected radiation resistance. On the other hand, the size of the initial population and the age of the conidia did not influence the radiation resistance of either strain. Studies on thermal inactivation of the conidia suggested that the temperature employed was more important than the time of heat treatment. Conidia of both strains showed a synergistic effect of combined heat and radiation treatments, although a heat-radiation sequence was more effective than a radiation-heat sequence. (author)

  15. The Shewanella algae strain YM8 produces volatiles with strong inhibition activity against Aspergillus pathogens and aflatoxins

    Directory of Open Access Journals (Sweden)

    Andong eGong

    2015-10-01

    Full Text Available Aflatoxigenic Aspergillus fungi and associated aflatoxins are ubiquitous in the production and storage of food/feed commodities. Controlling these pests is a challenge. In this study, the Shewanella algae strain YM8 was found to produce volatiles that have strong antifungal activity against Aspergillus pathogens. Gas chromatography-mass spectrometry profiling revealed 15 volatile organic compounds (VOCs emitted from YM8, of which dimethyl trisulfide was the most abundant. We obtained authentic reference standards for six of the VOCs; these all significantly reduced mycelial growth and conidial germination in Aspergillus; dimethyl trisulfide and 2,4-bis(1,1-dimethylethyl-phenol showed the strongest inhibitory activity. YM8 completely inhibited Aspergillus growth and aflatoxin biosynthesis in maize and peanut samples stored at different water activity levels, and scanning electron microscopy revealed severely damaged conidia and a complete lack of mycelium development and conidiogenesis. YM8 also completely inhibited the growth of eight other agronomically important species of phytopathogenic fungi: A. parasiticus, A. niger, Alternaria alternate, Botrytis cinerea, Fusarium graminearum, Fusarium oxysporum, Monilinia fructicola, and Sclerotinia sclerotiorum. This study demonstrates the susceptibility of Aspergillus and other fungi to VOCs from marine bacteria and indicates a new strategy for effectively controlling these pathogens and the associated mycotoxin production in the field and during storage.

  16. Variability in Galactomannan detection by platelia Aspergillus EIA™ according to the Aspergillus species

    Directory of Open Access Journals (Sweden)

    Melissa Orzechowski Xavier

    2013-06-01

    Full Text Available Here we investigate the extent to which different Aspergillus species release galactomannan (GM in vitro. Marked variability was observed in GM reactivity between and within Aspergillus species, with A. terreus strains showing the highest GM indexes. The in vivo significance of these findings remains to be determined.

  17. Ninety six well microtiter plate as microbioreactors for production of itaconic acid by six Aspergillus terreus strains

    Science.gov (United States)

    Itaconic acid (IA) is a building block platform chemical that is currently produced industrially from glucose by fermentation with Aspergillus terreus. However, lignocellulosic biomass has the potential to serve as low cost source of sugars for production of IA. Previously, 100 A. terreus strains we...

  18. Deletion of creB in Aspergillus oryzae increases secreted hydrolytic enzyme activity.

    Science.gov (United States)

    Hunter, A J; Morris, T A; Jin, B; Saint, C P; Kelly, J M

    2013-09-01

    Aspergillus oryzae has been used in the food and beverage industry for centuries, and industrial strains have been produced by multiple rounds of selection. Targeted gene deletion technology is particularly useful for strain improvement in such strains, particularly when they do not have a well-characterized meiotic cycle. Phenotypes of an Aspergillus nidulans strain null for the CreB deubiquitinating enzyme include effects on growth and repression, including increased activity levels of various enzymes. We show that Aspergillus oryzae contains a functional homologue of the CreB deubiquitinating enzyme and that a null strain shows increased activity levels of industrially important secreted enzymes, including cellulases, xylanases, amylases, and proteases, as well as alleviated inhibition of spore germination on glucose medium. Reverse transcription-quantitative PCR (RT-qPCR) analysis showed that the increased levels of enzyme activity in both Aspergillus nidulans and Aspergillus oryzae are mirrored at the transcript level, indicating transcriptional regulation. We report that Aspergillus oryzae DAR3699, originally isolated from soy fermentation, has a similar phenotype to that of a creB deletion mutant of the RIB40 strain, and it contains a mutation in the creB gene. Collectively, the results for Aspergillus oryzae, Aspergillus nidulans, Trichoderma reesei, and Penicillium decumbens show that deletion of creB may be broadly useful in diverse fungi for increasing production of a variety of enzymes.

  19. Strain improvement and optimization for β-glucosidase production in Aspergillus niger by low-energy N+ implantation

    International Nuclear Information System (INIS)

    Diao Jinshan; Wang Li; Chen Zhen; Liu Hui; Nie Guangjun; Zheng Zhiming

    2010-01-01

    Low-energy N + implantation was employed to mutate Aspergillus niger Au to enhance productivity of β-glucosidase. Effects of N + on strains, survival and mutation rate were studied. After several rounds of implantation, activity of β-glucosidase of the final mutant Au 0847 reached 13.75 U/mL, which is higher by 106.8% than that of original strain Au, and its heritability was stabilized. Activity of β-glucosidase of Au 0847 reached 30.53 U/mL after further fermentation condition optimization. (authors)

  20. Prospecting for the incidence of genes involved in ochratoxin and fumonisin biosynthesis in Brazilian strains of Aspergillus niger and Aspergillus welwitschiae.

    Science.gov (United States)

    Massi, Fernanda Pelisson; Sartori, Daniele; de Souza Ferranti, Larissa; Iamanaka, Beatriz Thie; Taniwaki, Marta Hiromi; Vieira, Maria Lucia Carneiro; Fungaro, Maria Helena Pelegrinelli

    2016-03-16

    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 species are morphologically very similar and molecular data are indispensable for their identification. A total of 175 Brazilian isolates previously identified as A. niger collected from dried fruits, Brazil nuts, coffee beans, grapes, cocoa and onions were investigated in this study. Based on partial calmodulin gene sequences about one-half of our isolates were identified as A. welwitschiae. This new species was the predominant species in onions analyzed in Brazil. A. niger and A. welwitschiae differ in their ability to produce ochratoxin A and fumonisin B2. Among A. niger isolates, approximately 32% were OTA producers, but in contrast only 1% of the A. welwitschiae isolates revealed the ability to produce ochratoxin A. Regarding fumonisin B2 production, there was a higher frequency of FB2 producing isolates in A. niger (74%) compared to A. welwitschiae (34%). Because not all A. niger and A. welwitschiae strains produce ochratoxin A and fumonisin B2, in this study a multiplex PCR was developed for detecting the presence of essential genes involved in ochratoxin (polyketide synthase and radHflavin-dependent halogenase) and fumonisin (α-oxoamine synthase) biosynthesis in the genome of A. niger and A. welwitschiae isolates. The frequency of strains harboring the mycotoxin genes was markedly different between A. niger and A. welwitschiae. All OTA producing isolates of A. niger and A. welwitschiae showed in their genome the pks and radH genes, and 95.2% of the nonproducing

  1. Aspergillus niger contains the cryptic phylogenetic species A. awamori.

    Science.gov (United States)

    Perrone, Giancarlo; Stea, Gaetano; Epifani, Filomena; Varga, János; Frisvad, Jens C; Samson, Robert A

    2011-11-01

    Aspergillus section Nigri is an important group of species for food and medical mycology, and biotechnology. The Aspergillus niger 'aggregate' represents its most complicated taxonomic subgroup containing eight morphologically indistinguishable taxa: A. niger, Aspergillus tubingensis, Aspergillus acidus, Aspergillus brasiliensis, Aspergillus costaricaensis, Aspergillus lacticoffeatus, Aspergillus piperis, and Aspergillus vadensis. Aspergillus awamori, first described by Nakazawa, has been compared taxonomically with other black aspergilli and recently it has been treated as a synonym of A. niger. Phylogenetic analyses of sequences generated from portions of three genes coding for the proteins β-tubulin (benA), calmodulin (CaM), and the translation elongation factor-1 alpha (TEF-1α) of a population of A. niger strains isolated from grapes in Europe revealed the presence of a cryptic phylogenetic species within this population, A. awamori. Morphological, physiological, ecological and chemical data overlap occurred between A. niger and the cryptic A. awamori, however the splitting of these two species was also supported by AFLP analysis of the full genome. Isolates in both phylospecies can produce the mycotoxins ochratoxin A and fumonisin B₂, and they also share the production of pyranonigrin A, tensidol B, funalenone, malformins, and naphtho-γ-pyrones. In addition, sequence analysis of four putative A. awamori strains from Japan, used in the koji industrial fermentation, revealed that none of these strains belong to the A. awamori phylospecies. Copyright © 2011 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  2. Discrimination of Aspergillus isolates at the species and strain level by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry fingerprinting.

    Science.gov (United States)

    Hettick, Justin M; Green, Brett J; Buskirk, Amanda D; Kashon, Michael L; Slaven, James E; Janotka, Erika; Blachere, Francoise M; Schmechel, Detlef; Beezhold, Donald H

    2008-09-15

    Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to generate highly reproducible mass spectral fingerprints for 12 species of fungi of the genus Aspergillus and 5 different strains of Aspergillus flavus. Prior to MALDI-TOF MS analysis, the fungi were subjected to three 1-min bead beating cycles in an acetonitrile/trifluoroacetic acid solvent. The mass spectra contain abundant peaks in the range of 5 to 20kDa and may be used to discriminate between species unambiguously. A discriminant analysis using all peaks from the MALDI-TOF MS data yielded error rates for classification of 0 and 18.75% for resubstitution and cross-validation methods, respectively. If a subset of 28 significant peaks is chosen, resubstitution and cross-validation error rates are 0%. Discriminant analysis of the MALDI-TOF MS data for 5 strains of A. flavus using all peaks yielded error rates for classification of 0 and 5% for resubstitution and cross-validation methods, respectively. These data indicate that MALDI-TOF MS data may be used for unambiguous identification of members of the genus Aspergillus at both the species and strain levels.

  3. Interaction of Wild Strains of Aspergilla with Aspergillus parasiticus ATCC15517 and Aflatoxin Production †

    Science.gov (United States)

    Martins, H. Marina; Almeida, Inês; Marques, Marta; Bernardo, Fernando

    2008-01-01

    Aflatoxins are secondary metabolites produced by some competent mould strains of Aspergillus flavus, A. parasiticus and A. nomius. These compounds have been extensively studied with regards to their toxicity for animals and humans; they are able to induce liver cancer and may cause a wide range of adverse effects in living organisms. Aflatoxins are found as natural contaminants of food and feed; the main line of the strategy to control them is based on the prevention of the mould growth in raw vegetable or during its storage and monitoring of each crop batch. Mould growth is conditioned by many ecological factors, including biotic ones. Hazard characterization models for aflatoxins in crops must take into consideration biotic interactions between moulds and their potential effects on growth development. The aim of this work is to study the effect of the biotic interaction of 14 different wild strains of Aspergilla (different species), with a competent strain (Aspergillus parasiticus ATCC 15517) using an in vitro production model. The laboratory model used was a natural matrix (humidified cracked corn), on which each wild strain challenged the aflatoxin production of a producer strain. Cultures were incubated at 28°C for 12 days and sampled at the 8th and 12th. Aflatoxin detection and quantification was performed by HPLC using a procedure with a MRPL = 1 μg/kg. Results of those interactive cultures revealed both synergic and antagonistic effects on aflatoxin biosynthesis. Productivity increases were particularly evident on the 8th day of incubation with wild strains of A. flavipes (+ 70.4 %), A. versicolor (+ 54.9 %) and A. flavus 3 (+ 62.6 %). Antagonistic effects were found with A. niger (− 69.5%), A. fumigatus (− 47.6 %) and A. terreus (− 47.6 %) on the 12th day. The increased effects were more evident on the 8th of incubation and the decreases were more patent on the 12th day. Results show that the development of Aspergilla strains concomitantly with

  4. Reversion in variants from a duplication strain of Aspergillus nidulans

    International Nuclear Information System (INIS)

    Menezes, E.M.; Azevedo, J.L.

    1978-01-01

    Strains of Aspergillus nidulans with a chromosome segment in duplicate, one in normal position and one translocated to another chromosome, are unstable at mitosis. In addition to variants which result from deletions in either of the duplicate segments, which usually have improved morphology, they produce variants with deteriorated morphology. Three deteriorated variants reverted frequently to parental type morphology, both spontaneously and after ultra-violet treatment. Of six reversions analysed genetically, five were due to suppressors and one was probably due to back mutation. The suppressors segregated as single genes and were not linked to the mutation which they suppress. The instability of these so-called 'deteriorated' variants is discussed in relation to mitotic instability phenomena in A. nidulans. (orig.) [de

  5. Pathogenicity of fumonisin-producing and nonproducing strains of Aspergillus species in section Nigri to maize ears and seedlings

    Science.gov (United States)

    Species of Aspergillus section Nigri are commonly associated with maize kernels, and some strains can produce fumonisin mycotoxins. However, there is little information about the extent to which these fungi contribute to fumonisin contamination in grain, the damage they cause to maize ears, or their...

  6. Effect of gamma radiation on Aspergillus flavus and Aspergillus ochraceus ultrastructure and mycotoxin production

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, J. [Departamento de Microbiologia e Inmunologia Veterinaria, Universidad Federal Rural de Rio de Janeiro (UFRRJ) (Brazil); Cavaglieri, L., E-mail: lcavaglieri@arnet.com.a [Departamento de Microbiologia e Inmunologia, Universidad Nacional de Rio Cuarto (UNRC), Rio Cuarto, Cordoba (Argentina); Member of Consejo Nacional de Investigaciones Cientificas y Tecnologicas (CIC-CONICET) (Argentina); Vital, H. [Centro Tecnologico do Exercito (CTEx), Secao de Defesa Nuclear, Rio de Janeiro (Brazil); Cristofolini, A.; Merkis, C. [Departamento de Microscopia Electronica, Universidad Nacional de Rio Cuarto. Ruta 36 km 601 (5800) Rio Cuarto (Argentina); Astoreca, A. [Departamento de Microbiologia e Inmunologia, Universidad Nacional de Rio Cuarto (UNRC), Rio Cuarto, Cordoba (Argentina); Member of Consejo Nacional de Investigaciones Cientificas y Tecnologicas (CIC-CONICET) (Argentina); Orlando, J.; Caru, M. [Departamento de Ciencias Ecologicas, Facultad de Ciencias, Universidad de Chile, Santiago (Chile); Dalcero, A. [Departamento de Microbiologia e Inmunologia, Universidad Nacional de Rio Cuarto (UNRC), Rio Cuarto, Cordoba (Argentina); Member of Consejo Nacional de Investigaciones Cientificas y Tecnologicas (CIC-CONICET) (Argentina); Rosa, C.A.R. [Departamento de Microbiologia e Inmunologia Veterinaria, Universidad Federal Rural de Rio de Janeiro (UFRRJ) (Brazil); Member of Consejo Nacional de Pesquisas (CNPq) (Brazil)

    2011-05-15

    The aim of this work was to study the effect of gamma radiation (2 kGy) on Aspergillus flavus and Aspergillus ochraceus ultrastructure. Moreover, the influence on aflatoxin B{sub 1} and ochratoxin A production was also observed. Irradiated A. flavus strain showed a dull orangish colony while control strain showed the typical green color. Minor differences were observed on stipes, metulae and conidia size between control and irradiated A. flavus and A. ochraceus strains. Irradiated fungi showed ultrastructural changes on cell wall, plasmalema and cytoplasm levels. The levels of mycotoxins produced by irradiated strains were two times greater than those produced by control strains. Successive transferences of irradiated strains on malt extract agar allowed the fungus to recuperate morphological characteristics. Although minor changes in the fungal morphology were observed, ultrastructural changes at cell wall level and the increase of mycotoxin production ability were observed. Inappropriate storage of irradiated food and feed would allow the development of potentially more toxicogenic fungal propagules.

  7. Effect of gamma radiation on Aspergillus flavus and Aspergillus ochraceus ultrastructure and mycotoxin production

    International Nuclear Information System (INIS)

    Ribeiro, J.; Cavaglieri, L.; Vital, H.; Cristofolini, A.; Merkis, C.; Astoreca, A.; Orlando, J.; Caru, M.; Dalcero, A.; Rosa, C.A.R.

    2011-01-01

    The aim of this work was to study the effect of gamma radiation (2 kGy) on Aspergillus flavus and Aspergillus ochraceus ultrastructure. Moreover, the influence on aflatoxin B 1 and ochratoxin A production was also observed. Irradiated A. flavus strain showed a dull orangish colony while control strain showed the typical green color. Minor differences were observed on stipes, metulae and conidia size between control and irradiated A. flavus and A. ochraceus strains. Irradiated fungi showed ultrastructural changes on cell wall, plasmalema and cytoplasm levels. The levels of mycotoxins produced by irradiated strains were two times greater than those produced by control strains. Successive transferences of irradiated strains on malt extract agar allowed the fungus to recuperate morphological characteristics. Although minor changes in the fungal morphology were observed, ultrastructural changes at cell wall level and the increase of mycotoxin production ability were observed. Inappropriate storage of irradiated food and feed would allow the development of potentially more toxicogenic fungal propagules.

  8. Study of itaconic acid production by Aspergillus terrus MJL05 strain with different variable

    Directory of Open Access Journals (Sweden)

    Mariana Juy

    2010-07-01

    Full Text Available Título en español: Estudio de la producción de ácido itacónico con Aspergillus terreus de la cepa MJL05 con diferentes variables Abstract Itaconic acid (IA production by Aspergillus terreus MJL05 strain was investigated in submerged batch fermentation in a stirred bioreactor to determine the effect of varying the nitrogen, phosphorous and carbon sources concentrations in the production medium. Glycerol, a biodiesel by-product was reported as an efficient substrate to achieve high itaconic acid productivities. This was used as the sole carbon source. The resulting C:N 18, N:P 10.8 and C:P 195 ratios were selected as the best and allowed to improve IA concentration from 11.0 to 27.6 g/l with a volumetric productivity of 0.192 g IA/l.h and a specific productivity 0.013 g IA/g biomass.h. Bioprocess yields, Yx:s 0.27 g d.w. biomass/g substrate; Yp:x 1.63 g IA/g d.w. biomass and Yp:s 0.44 g IA/g substrate, allowed to assume the feasibility of using this strain for IA production. Key words: Itaconic acid; Aspergillus terreus; glycerol. Resumen La producción de ácido itacónico (AI con Aspergillus terreus MJL05 se realizó en fermentación sumergida en lote en un biorreactor agitado para estudiar el efecto de la variación de las concentraciones de nitrógeno, fósforo y carbono en el medio de producción. El glicerol, subproducto del biodiesel, fue reportado como un sustrato eficiente para obtener altas productividades de AI. Este fue utilizado como única fuente de carbono. Las relaciones entre nutrientes, C:N 18, N:P 10,8 y C:P 195 fueron seleccionadas como las mejores para aumentar la concentración de AI de 11,0 a 27,6 g/l con un a productividad volumétrica de 0,192 g IA/l.h, y una productividad específica de 0,013 g IA/g biomasa.h. Los rendimientos del bioproceso obtenidos fueron de Yx:s 0,27 g p.s. biomasa/g sustrato; Yp:x 1,63 g IA/g p.s. biomasa y Yp:s 0,44 g IA/g sustrato, lo que permite asumir la factibilidad de usar esta cepa para

  9. A Comparative Study of New Aspergillus Strains for Proteolytic Enzymes Production by Solid State Fermentation

    Directory of Open Access Journals (Sweden)

    Gastón Ezequiel Ortiz

    2016-01-01

    Full Text Available A comparative study of the proteolytic enzymes production using twelve Aspergillus strains previously unused for this purpose was performed by solid state fermentation. A semiquantitative and quantitative evaluation of proteolytic activity were carried out using crude enzymatic extracts obtained from the fermentation cultures, finding seven strains with high and intermediate level of protease activity. Biochemical, thermodynamics, and kinetics features such as optimum pH and temperature values, thermal stability, activation energy (Ea, quotient energy (Q10, Km, and Vmax were studied in four enzymatic extracts from the selected strains that showed the highest productivity. Additionally, these strains were evaluated by zymogram analysis obtaining protease profiles with a wide range of molecular weight for each sample. From these four strains with the highest productivity, the proteolytic extract of A. sojae ATCC 20235 was shown to be an appropriate biocatalyst for hydrolysis of casein and gelatin substrates, increasing its antioxidant activities in 35% and 125%, respectively.

  10. Transcriptome of Aspergillus flavus aswA (AFLA_085170) deletion strain related to sclerotial development and production of secondary metabolites

    Science.gov (United States)

    Aspergillus flavus produces many secondary metabolites including aflatoxins. Besides conidia, the fungus uses sclerotia as another type of propagule. We obtained transcriptomes from four growth conditions of the aswA mutant, a strain impaired in sclerotial development and production of sclerotium-sp...

  11. Genetic diversity of Aspergillus species isolated from onychomycosis and Aspergillus hongkongensis sp. nov., with implications to antifungal susceptibility testing.

    Science.gov (United States)

    Tsang, Chi-Ching; Hui, Teresa W S; Lee, Kim-Chung; Chen, Jonathan H K; Ngan, Antonio H Y; Tam, Emily W T; Chan, Jasper F W; Wu, Andrea L; Cheung, Mei; Tse, Brian P H; Wu, Alan K L; Lai, Christopher K C; Tsang, Dominic N C; Que, Tak-Lun; Lam, Ching-Wan; Yuen, Kwok-Yung; Lau, Susanna K P; Woo, Patrick C Y

    2016-02-01

    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/ionization time-of-flight mass spectrometry. The 13th isolate (HKU49(T)) possessed unique morphological characteristics different from other Aspergillus spp. Molecular characterization also unambiguously showed that HKU49(T) was distinct from other Aspergillus spp. We propose the novel species Aspergillus hongkongensis to describe this previously unknown fungus. Antifungal susceptibility testing showed most Aspergillus isolates had low MICs against itraconazole and voriconazole, but all Aspergillus isolates had high MICs against fluconazole. A diverse spectrum of Aspergillus species is associated with onychomycosis. Itraconazole and voriconazole are probably better drug options for Aspergillus onychomycosis. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Biomarkers of Aspergillus spores

    Science.gov (United States)

    Sulc, Miroslav; Peslova, Katerina; Zabka, Martin; Hajduch, Marian; Havlicek, Vladimir

    2009-02-01

    We applied both matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometric and 1D sodium dodecylsulfate polyacrylamide gel electrophoretic (1D-PAGE) approaches for direct analysis of intact fungal spores of twenty four Aspergillus species. In parallel, we optimized various protocols for protein extraction from Aspergillus spores using acidic conditions, step organic gradient and variable sonication treatment. The MALDI-TOF mass spectra obtained from optimally prepared samples provided a reproducible fingerprint demonstrating the capability of the MALDI-TOF approach to type and characterize different fungal strains within the Aspergillus genus. Mass spectra of intact fungal spores provided signals mostly below 20 kDa. The minimum material amount represented 0.3 [mu]g (10,000 spores). Proteins with higher molecular weight were detected by 1D-PAGEE Eleven proteins were identified from three selected strains in the range 5-25 kDa by the proteomic approach. Hemolysin and hydrophobin have the highest relevance in host-pathogen interactions.

  13. Study of itaconic acid production by Aspergillus terrus MJL05 strain with different variable

    OpenAIRE

    Juy, M. I.; Orejas, J. A.; Lucca, M. E.

    2010-01-01

    Itaconic acid (IA) production by Aspergillus terreus MJL05 strain was investigated in submerged batch fermentation in a stirred bioreactor to determine the effect of varying the nitrogen, phosphorous and carbon sources concentrations in the production medium. Glycerol, a biodiesel by-product was reported as an efficient substrate to achieve high itaconic acid productivities. This was used as the sole carbon source. The resulting C:N 18, N:P 10.8 and C:P 195 ratios were selected as the best an...

  14. A quick method for testing recessive lethal damage with a diploid strain of Aspergillus nidulans

    International Nuclear Information System (INIS)

    Morpurgo, G.; Puppo, S.; Gualandi, G.; Conti, L.

    1978-01-01

    A simple method capable of detecting recessive lethal damage in a diploid strain of Aspergillus nidulans is described. The method scores the recessive lethals on the 1st, the 3rd and the 5th chromosomes, which represent about 40% of the total map of A. nidulans. Two examples of induced lethals, with ultraviolet irradiation and methyl methanesulfonate are shown. The frequency of lethals may reach 36% of the total population with UV irradiation. (Auth.)

  15. Influence of gamma irradiation on natural mycoflora of poultry feed and effect on morphology, physiology and genetic of strains Aspergillus spp

    International Nuclear Information System (INIS)

    Ribeiro, Jessika Mara Martins

    2008-01-01

    Maize flour samples, soy crumb and feed were collected directly from the production line of a poultry farm in Avelar, RJ, and exposed to doses of 0,3.5, 0,8 and 15 kGy of gamma irradiation. Counting, isolation and identification of the contaminant mycoflora were performed before and after irradiation. The radiosensitivity of strains of reference of Aspergillus spp. was determined in CYA medium and in corn for doses ranging from 0 to 8 kGy. Comparison between the morphologies of control and irradiated strains were performed by using macroscopy, optical microscopy and transmission electron microscopy. Toxigenic profile determination and genetic evaluation by RAPD were also carried out. Higher doses have been found to reduce the number of active colonies, causing elimination of the mycoflora at 8 kGy. A larger radiosensitivity of yeasts was observed in comparison with filamentous fungi. A significant reduction in fungi population occurred at 3.5 kGy to levels below the limit that ensures the hygienic quality of ingredients and poultry feeds. The residual mycoflora was found to decrease with post-irradiation time and included mostly Cladosporium spp., Curvularia spp., Fusarium spp. and Aspergillus spp. and sterility of mycelium prevented further identification of the surviving species of Aspergillus spp. Differences in radioresistance were found among species of Aspergillus and the highest tolerance to radiation was observed for A. parasiticus. Initial morphologic changes were found to be more severe during the first isolation after irradiation than in later ones, with the fungi gradually recovering their normal growth rate. Ultrastructural changes in the irradiated strains were observed mostly in the plasmatic membrane and membranous organelles of nuclei and mitochondria. An increase in the rate of production of toxins by the irradiated strains has been found, however no significant alterations have been observed in their genotypes. Such findings apparently indicate

  16. Typing clinical and animal environment Aspergillus fumigatus gliotoxin producer strains isolated from Brazil by PCR-RFLP markers.

    Science.gov (United States)

    Soleiro, C A; Pena, G A; Cavaglieri, L R; Coelho, I; Keller, L M; Dalcero, A M; Rosa, C A R

    2013-12-01

    Aspergillus fumigatus, a well-known human and animal pathogen causing aspergillosis, has been historically identified by morphological and microscopic features. However, recent studies have shown that species identification on the basis of morphology alone is problematic. The aim of this work was to confirm the taxonomic state at specie level of a set of clinical (human and animal) and animal environment A. fumigatus strains identified by morphological criteria applying a PCR-RFLP assay by an in silico and in situ analysis with three restriction enzymes. The A. fumigatus gliotoxin-producing ability was also determined. Previous to the in situ PCR-RFLP analysis, an in silico assay with BccI, MspI and Sau3AI restriction enzymes was carried out. After that, these enzymes were used for in situ assay. All A. fumigatus strains isolated from corn silage, human aspergillosis and bovine mastitis and high per cent of the strains isolated from cereals, animal feedstuff and sorghum silage were able to produce high gliotoxin levels. Also, all these strains identified by morphological criteria as A. fumigatus, regardless of its isolation source, had band patterns according to A. fumigatus sensu stricto by PCR-RFLP markers. Aspergillus fumigatus is a well-known human and animal pathogen causing aspergillosis. In this study, clinical (human and animal) and animal environment strains were able to produce high gliotoxin levels and had band profiles according to A. fumigatus sensu stricto by PCR-RFLP markers. The results obtained here suggest that strains involved in human and animal aspergillosis could come from the animal environment in which A. fumigatus is frequently found. Its presence in animal environments could affect animal health and productivity; in addition, there are risks of contamination for rural workers during handling and storage of animal feedstuffs. © 2013 The Society for Applied Microbiology.

  17. Utilization of Low-Cost Ellagitannins for Ellagic Acid Production and Antimicrobial Phenolics Enhancing By Aspergillus awamorii and Aspergillus oryzae

    International Nuclear Information System (INIS)

    El-Bialy, H.A.; Abd EL-Aziz, A.B.

    2009-01-01

    Three fungal strains, Aspergillus awamorii A 9 , Aspergillus awamorii A 2 3 and Aspergillus oryzae O 2 , were selected out of ten fungal strains for their activeness in converting pomegranate peel ellagitannins into ellagic acid. When pomegranate peel was fermented by Aspergillus awamorii A 9 , the highest yields of ellagic acid (7.93±0.23 mg/g solid substrate) and total soluble phenolics (14.61±0.36 mg/g solid substrate) were produced at 5 and 10 days of incubation, respectively. Also, blue berry pomace, red grape pomace, strawberry pomace were evaluated as low cost ellagitannin sources for ellagic acid and soluble phenolics production. The antimicrobial activity of soluble phenolics extracted from fermented pomegranate peel and strawberry pomace was tested against two food-borne pathogens (Escherichia coli and Salmonella typhimurium). This study also revealed that 3 kGy enhanced the activity of antimicrobial phenolics

  18. Molecular Detection of Aflatoxin Producing Strains of Aspergillus Flavus from Peanut (Arachis Hypogaea

    Directory of Open Access Journals (Sweden)

    Adeela Hussain

    2015-02-01

    Full Text Available Aflatoxins are the potential carcinogens produced as secondary metabolites by Aspergillus flavus. They have the ability to contaminate large number of food which ultimately affect the human population. Malt extract agar was selected for the growth of control stains of fungus. The aim of the study was to develop a reliable and quick method for the detection of aflatoxin producing strains in peanuts by using molecular approaches. Total 80 samples of infected peanuts were collected from four different cities of Punjab and checked for their aflatoxin contamination. For aflatoxin detection, three target genes nor1, ver1 and aflR were selected which was involved in the aflatoxin biosynthesis. In all examined cases, 24 out of 80 (30% samples successfully amplified all three genes indicating aflatoxigenic activity. Discrimination between aflatoxigenic and non-aflatoxigenic strains were also determined on the basis of amplification of these three target DNA fragments. In this study, it was also demonstrated that only specific strains were able to produce the aflatoxin contamination in peanuts.

  19. Intra and extracellular nuclease production by Aspergillus niger and Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    Ferreira Adlane V. B.

    1998-01-01

    Full Text Available Intra and extracellular nuclease production by strains of Aspergillus niger and Aspergillus nidulans was estimated using a modified DNAse test agar and cell-free extract assays. Differences in the production of nucleases by A. niger and A. nidulans were observed. These observations suggest that the DNAse test agar can be helpful for a quick screening for some types of nucleases in filamentous fungi. The assays using cell-free extracts can also be useful for initial characterization of other types of nucleases.

  20. Isolation of industrial strains of Aspergillus oryzae lacking ferrichrysin by disruption of the dffA gene.

    Science.gov (United States)

    Watanabe, Hisayuki; Hatakeyama, Makoto; Sakurai, Hiroshi; Uchimiya, Hirofumi; Sato, Toshitsugu

    2008-11-01

    Based on studies using laboratory strains, the efficiency of gene disruption in Aspergillus oryzae, commonly known as koji mold, is low; thus, gene disruption has rarely been applied to the breeding of koji mold. To evaluate the efficiency of gene disruption in industrial strains of A. oryzae, we produced ferrichrysin biosynthesis gene (dffA) disruptants using three different industrial strains as hosts. PCR analysis of 438 pyrithiamine-resistant transformants showed dffA gene disruption efficiency of 42.9%-64.1%, which is much higher than previously reported. Analysis of the physiological characteristics of the disruptants indicated that dffA gene disruption results in hypersensitivity to hydrogen peroxide. To investigate the industrial characteristics of dffA gene disruptants, two strains were used to make rice koji and their properties were compared to those of the host strains. No differences were found between the dffA gene disruptants and the host strains, except that the disruptants did not produce ferrichrysin. Thus, this gene disruption technique is much more effective than conventional mutagenesis for A. oryzae breeding.

  1. Biochemical properties of Cu/Zn-superoxide dismutase from fungal strain Aspergillus niger 26

    Science.gov (United States)

    Dolashki, Aleksandar; Abrashev, Radoslav; Stevanovic, Stefan; Stefanova, Lilyana; Ali, Syed Abid; Velkova, Ludmila; Hristova, Rumyana; Angelova, Maria; Voelter, Wolfgang; Devreese, Bart; Van Beeumen, Jozef; Dolashka-Angelova, Pavlina

    2008-12-01

    The fungal strain Aspergillus niger produces two superoxide dismutases, Cu/Zn-SOD and Mn-SOD. The primary structure of the Cu/Zn-SOD has been determined by Edman degradation of peptide fragments derived from proteolytic digests. A single chain of the protein, consisting of 153 amino acid residues, reveals a very high degree of structural homology with the amino acid sequences of other Aspergillus Cu/Zn-SODs. The molecular mass of ANSOD, measured by MALDI-MS and ESI-MS, and calculated by its amino acid sequence, was determined to be 15 821 Da. Only one Trp residue, at position 32, and one disulfide bridge were identified. However, neither a Tyr residue nor a carbohydrate chain occupying an N-linkage site (-Asn-Ile-Thr-) were found. Studies on the temperature and pH dependence of fluorescence, and on the temperature dependence of CD spectroscopic properties, confirmed that the enzyme is very stable, which can be explained by the stabilising effect of the disulfide bridge. The enzyme retains about 53% of its activity after incubation for a period of 30 min at 60 °C, and 15% at 85 °C.

  2. Metabolomics Analysis Reveals Specific Novel Tetrapeptide and Potential Anti-Inflammatory Metabolites in Pathogenic Aspergillus species.

    Science.gov (United States)

    Lee, Kim-Chung; Tam, Emily W T; Lo, Ka-Ching; Tsang, Alan K L; Lau, Candy C Y; To, Kelvin K W; Chan, Jasper F W; Lam, Ching-Wan; Yuen, Kwok-Yung; Lau, Susanna K P; Woo, Patrick C Y

    2015-06-17

    Infections related to Aspergillus species have emerged to become an important focus in infectious diseases, as a result of the increasing use of immunosuppressive agents and high fatality associated with invasive aspergillosis. However, laboratory diagnosis of Aspergillus infections remains difficult. In this study, by comparing the metabolomic profiles of the culture supernatants of 30 strains of six pathogenic Aspergillus species (A. fumigatus, A. flavus, A. niger, A. terreus, A. nomius and A. tamarii) and 31 strains of 10 non-Aspergillus fungi, eight compounds present in all strains of the six Aspergillus species but not in any strain of the non-Aspergillus fungi were observed. One of the eight compounds, Leu-Glu-Leu-Glu, is a novel tetrapeptide and represents the first linear tetrapeptide observed in Aspergillus species, which we propose to be named aspergitide. Two other closely related Aspergillus-specific compounds, hydroxy-(sulfooxy)benzoic acid and (sulfooxy)benzoic acid, may possess anti-inflammatory properties, as 2-(sulfooxy)benzoic acid possesses a structure similar to those of aspirin [2-(acetoxy)benzoic acid] and salicylic acid (2-hydroxybenzoic acid). Further studies to examine the potentials of these Aspergillus-specific compounds for laboratory diagnosis of aspergillosis are warranted and further experiments will reveal whether Leu-Glu-Leu-Glu, hydroxy-(sulfooxy)benzoic acid and (sulfooxy)benzoic acid are virulent factors of the pathogenic Aspergillus species.

  3. Isolation, characterization and transcriptome analysis of a novel Antarctic Aspergillus sydowii strain MS-19 as a potential lignocellulosic enzyme source.

    Science.gov (United States)

    Cong, Bailin; Wang, Nengfei; Liu, Shenghao; Liu, Feng; Yin, Xiaofei; Shen, Jihong

    2017-05-30

    applications of the novel Antarctic Aspergillus sydowii strain MS-19 as a potential lignocellulosic enzyme source.

  4. Tolerance to silver of an Aspergillus fumigatus strain able to grow on cyanide containing wastes

    Energy Technology Data Exchange (ETDEWEB)

    Sabatini, L. [Department of Biomolecular Sciences, University of Urbino Carlo Bo (Italy); Battistelli, M. [Department of Earth, Life Sciences & Environment, University of Urbino Carlo Bo (Italy); Giorgi, L. [Department of Base Sciences and Foundations, Chemistry Section, University of Urbino Carlo Bo (Italy); Iacobucci, M. [Department of Earth, Life Sciences & Environment, University of Urbino Carlo Bo (Italy); Gobbi, L. [Department of Science and Engineering of Matter, of Environment and Urban Planning, Polytechnic University of Marche, Ancona (Italy); Andreozzi, E.; Pianetti, A. [Department of Biomolecular Sciences, University of Urbino Carlo Bo (Italy); Franchi, R. [Department of Base Sciences and Foundations, Chemistry Section, University of Urbino Carlo Bo (Italy); Bruscolini, F., E-mail: francesca.bruscolini@uniurb.it [Department of Biomolecular Sciences, University of Urbino Carlo Bo (Italy)

    2016-04-05

    Highlights: • Aspergillus fumigatus strain able to grow on metal cyanide complexes. • Tolerance test revealed that Ag(I) Minimum Inhibitory Concentration was 6 mM. • The fungus reduced and sequestrated intracellularly silver forming nanoparticles. • Best culture conditions for Ag(I) absorption were pH 8.5 at temperatures of 20–30 °C. - Abstract: We studied the strategy of an Aspergillus fumigatus strain able to grow on metal cyanide wastes to cope with silver. The tolerance test revealed that the Minimum Inhibitory Concentration of Ag(I) was 6 mM. In 1 mM AgNO{sub 3} aqueous solution the fungus was able to reduce and sequestrate silver into the cell in the form of nanoparticles as evidenced by the change in color of the biomass and Electron Microscopy observations. Extracellular silver nanoparticle production also occurred in the filtrate solution after previous incubation of the fungus in sterile, double-distilled water for 72 h, therefore evidencing that culture conditions may influence nanoparticle formation. The nanoparticles were characterized by UV–vis spectrometry, X-ray diffraction and Energy Dispersion X-ray analysis. Atomic absorption spectrometry revealed that the optimum culture conditions for silver absorption were at pH 8.5.The research is part of a polyphasic study concerning the behavior of the fungal strain in presence of metal cyanides; the results provide better understanding for further research targeted at a rationale use of the microorganism in bioremediation plans, also in view of possible metal recovery. Studies will be performed to verify if the fungus maintains its ability to produce nanoparticles using KAg(CN){sub 2}.

  5. Tolerance to silver of an Aspergillus fumigatus strain able to grow on cyanide containing wastes

    International Nuclear Information System (INIS)

    Sabatini, L.; Battistelli, M.; Giorgi, L.; Iacobucci, M.; Gobbi, L.; Andreozzi, E.; Pianetti, A.; Franchi, R.; Bruscolini, F.

    2016-01-01

    Highlights: • Aspergillus fumigatus strain able to grow on metal cyanide complexes. • Tolerance test revealed that Ag(I) Minimum Inhibitory Concentration was 6 mM. • The fungus reduced and sequestrated intracellularly silver forming nanoparticles. • Best culture conditions for Ag(I) absorption were pH 8.5 at temperatures of 20–30 °C. - Abstract: We studied the strategy of an Aspergillus fumigatus strain able to grow on metal cyanide wastes to cope with silver. The tolerance test revealed that the Minimum Inhibitory Concentration of Ag(I) was 6 mM. In 1 mM AgNO 3 aqueous solution the fungus was able to reduce and sequestrate silver into the cell in the form of nanoparticles as evidenced by the change in color of the biomass and Electron Microscopy observations. Extracellular silver nanoparticle production also occurred in the filtrate solution after previous incubation of the fungus in sterile, double-distilled water for 72 h, therefore evidencing that culture conditions may influence nanoparticle formation. The nanoparticles were characterized by UV–vis spectrometry, X-ray diffraction and Energy Dispersion X-ray analysis. Atomic absorption spectrometry revealed that the optimum culture conditions for silver absorption were at pH 8.5.The research is part of a polyphasic study concerning the behavior of the fungal strain in presence of metal cyanides; the results provide better understanding for further research targeted at a rationale use of the microorganism in bioremediation plans, also in view of possible metal recovery. Studies will be performed to verify if the fungus maintains its ability to produce nanoparticles using KAg(CN) 2 .

  6. Enzymic hydrolysis of xylans. I. A high xylanase and beta-xylosidase producing strain of Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Conrad, D.

    1981-01-01

    Aspergillus niger, strain 110.42 (CBS) was selected as a producer of high xylanolytic activities. The time course of xylanase and beta-xylosidase production as well as the effect of pH and temperature on the activity of these enzymes were studied. High-performance liquid chromatography analysis of the enzymic degradation of arabinoxylan showed a nearly complete conversion to pentose sugars. Aspects of using crude xylanase preparations for enzymic saccharification of xylans are discussed.

  7. Efficient gene replacements in ku70 disruption strain of Aspergillus chevalieri var. intermedius

    Directory of Open Access Journals (Sweden)

    Qingqing Huang

    2017-01-01

    Full Text Available Aspergillus chevalieri var. intermedius is a dominant filamentous fungal species in Fuzhuan tea and is associated with the quality and health benefits of this tea. The sexual or asexual reproduction of this fungus depends on the osmotic pressure of the tea. Efforts to enhance the beneficial effects of A. chevalieri var. intermedius are hampered by difficulties in disrupting its genes. To address this issue, we identified the A. chevalieri var. intermedius homolog (Acku70 of human Ku70 and generated an Acku70 disruption strain (ΔAcku70, aiming to improve the gene replacement efficiency. ΔAcku70 grew at a slightly lower rate in vitro than the wild-type strain; however, the two strains exhibited similar sensitivity to temperature, osmotic pressure and the effects of ethyl methane sulphonate and H2O2. The replacement efficiency of veA and flbA dramatically increased in ΔAcku70 compared to that in the wild type. The efficiency of flbA replacement increased from 2.6% to 80%, whereas the frequency of veA disruption increased from 15.2% to 83.9% and from 30.8% to 86.8%. Thus, ΔAcku70 is suitable for use as a type strain for large-scale functional genomic analysis of A. chevalieri var. intermedius.

  8. The amyR-deletion strain of Aspergillus niger CICC2462 is a suitable host strain to express secreted protein with a low background.

    Science.gov (United States)

    Zhang, Hui; Wang, Shuang; Zhang, Xiang Xiang; Ji, Wei; Song, Fuping; Zhao, Yue; Li, Jie

    2016-04-28

    The filamentous fungus Aspergillus niger is widely exploited as an important expression host for industrial production. The glucoamylase high-producing strain A. niger CICC2462 has been used as a host strain for the establishment of a secretion expression system. It expresses recombinant xylanase, mannase and asparaginase at a high level, but some high secretory background proteins in these recombinant strains still remain, such as alpha-amylase and alpha-glucosidase; lead to a low-purity of fermentation products. The aim was to construct an A. niger host strain with a low background of protein secretion. The transcription factor amyR was deleted in A. niger CICC2462, and the results from enzyme activity assays and SDS-PAGE analysis showed that the glucoamylase and amylase activities of the ∆amyR strains were significantly lower than those of the wild-type strain. High-throughput RNA-sequencing and shotgun LC-MS/MS proteomic technology analysis demonstrated that the expression of amylolytic enzymes was decreased at both the transcriptional and translational levels in the ∆amyR strain. Interestingly, the ∆amyR strain growth rate better than the wild-type strain. Our findings clearly indicated that the ∆amyR strain of A. niger CICC2462 can be used as a host strain with a low background of protein secretion.

  9. [Morphological characteristics and physiological properties of aflatoxin B1 producing and non-producing Aspergillus flavus strains].

    Science.gov (United States)

    Kogbo, W; Lemarinier, S; Boutibonnes, P

    1985-09-01

    Comparison between about 80 strains of Aspergillus flavus, belonging to the series flavus and oryzae, obtained from international collections but also isolated from French or African substrates revealed the following observations: 1. Cultural and morphological characteristics of toxicogenic and atoxicogenic strains of A. flavus are similar. However, the former produce a diffusible yellow pigment in 83% of isolates. 2. The two groups of conidiospores have the same resistance to UV irradiation (254 nm, 5 and 10 min). All the strains are equally sensitive to 4 antifungal antibiotics: nystatine, ketoconazole, clotrimazole and amphotericine. 3. A difference was seen in the capacity to produce enzymes as alpha-galactosidase, beta-galactosidase and beta-glucosidase, implicated in the glucid metabolism. The specific hydrolytic activity has been confirmed by the characterization of a large amount of beta-galactosidase and by a diauxic growth on glucose medium supplemented by lactose. Possible relationship between these characters and aflatoxin B1 production by A. flavus strains is discussed.

  10. EFSA CEF Panel (EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids), 2014. Scientific Opinion on lipase from a genetically modified strain of Aspergillus oryzae (strain NZYM-FL)

    DEFF Research Database (Denmark)

    Poulsen, Morten; Hallas-Møller, Torben; Binderup, Mona-Lise

    The food enzyme considered in this opinion is a lipase (triacylglycerol lipase; EC 3.1.1.3) produced with a genetically modified strain of Aspergillus oryzae. The genetic modifications do not raise safety concern. The food enzyme contains neither the production organism nor recombinant DNA...

  11. Aspergillus atacamensis and A. salisburgensis: two new halophilic species from hypersaline/arid habitats with a phialosimplex-like morphology.

    Science.gov (United States)

    Martinelli, Livia; Zalar, Polona; Gunde-Cimerman, Nina; Azua-Bustos, Armando; Sterflinger, Katja; Piñar, Guadalupe

    2017-07-01

    Halophilic fungal strains isolated from historical wooden staircase in a salt mine in Austria, and from wall biofilm and soil of a cave in the Coastal Range of the hyperarid Atacama Desert in Chile were characterised and described newly as Aspergillus salisburgensis and Aspergillus atacamensis. Morphological characters including solitary phialides producing solitary conidia and conidia in chains and/or heads suggested affinity to Aspergillus subgenus Polypaecilum. Strains required salt for growth, grew optimally on media with 10-25% NaCl and at 15-28 °C. These values are similar to those observed for Aspergillus salinarus comb. nov. (Phialosimplex salinarum), while the ex-type strains of Aspergillus sclerotialis, Aspergillus chlamydosporus and Aspergillus caninus (all belonging to Aspergillus subgen. Polypaecilum) grew optimally at 0-5% NaCl and showed fastest growth at 28-37 °C. Phylogenetic analyses on the basis of rDNA sequences, RAPD-PCR fingerprint patterns, and cellobiohydrolase gene (cbh-I) polymorphism clustered the strains into three groups and supported their taxonomic recognition as A. salinarus, A. atacamensis and A. salisburgensis. On the basis of phylogenetic inferences, also Sagenomella keratitidis is newly combined as Aspergillus keratitidis and inferred as a species of Aspergillus subgenus Polypaecilum.

  12. Different action of MMS and EMS in UV-sensitive strains of Aspergillus nidulans.

    Science.gov (United States)

    Babudri, N; Politi, M G

    1989-05-01

    The repair of methyl methanesulfonate (MMS) and ethyl methanesulfonate (EMS) damages has been investigated in the fungus Aspergillus nidulans. 4 UV-sensitive mutants, namely uvsB, uvsD, uvsF and uvsH have been tested for their sensitivity and mutability to the above-mentioned agents. The results obtained show that: (1) uvsB and uvsD mutants are no more sensitive than the wild-type strain to the lethal action of EMS. In contrast, they are more sensitive to MMS; (2) uvsF and uvsH mutants are more sensitive than the wild type to EMS at 37 degrees C but not at 20 degrees C. However, they are more sensitive than the wild type to MMS at 37 degrees C as well as at 20 degrees C; (3) the mutation frequencies after treatment with either MMS or EMS plotted against survival are not altered in the UV-sensitive strains compared to the wild-type strain. From these data it may be concluded that the repair of lethal lesions induced by ethylating and methylating agents is under the control of different pathways. Furthermore the mutants tested are not involved in the mutagenic process.

  13. Metabolomic Tools to Assess the Chemistry and Bioactivity of Endophytic Aspergillus Strain.

    Science.gov (United States)

    Tawfike, Ahmed F; Tate, Rothwelle; Abbott, Gráinne; Young, Louise; Viegelmann, Christina; Schumacher, Marc; Diederich, Marc; Edrada-Ebel, RuAngelie

    2017-10-01

    Endophytic fungi associated with medicinal plants are a potential source of novel chemistry and biology that may find applications as pharmaceutical and agrochemical drugs. In this study, a combination of metabolomics and bioactivity-guided approaches were employed to isolate secondary metabolites with cytotoxicity against cancer cells from an endophytic Aspergillus aculeatus. The endophyte was isolated from the Egyptian medicinal plant Terminalia laxiflora and identified using molecular biological methods. Metabolomics and dereplication studies were accomplished by utilizing the MZmine software coupled with the universal Dictionary of Natural Products database. Metabolic profiling, with aid of multivariate data analysis, was performed at different stages of the growth curve to choose the optimized method suitable for up-scaling. The optimized culture method yielded a crude extract abundant with biologically-active secondary metabolites. Crude extracts were fractionated using different high-throughput chromatographic techniques. Purified compounds were identified by HR-ESI-MS, 1D- and 2D-NMR. This study introduced a new method of dereplication utilizing both high-resolution mass spectrometry and NMR spectroscopy. The metabolites were putatively identified by applying a chemotaxonomic filter. We also present a short review on the diverse chemistry of terrestrial endophytic strains of Aspergillus, which has become a part of our dereplication work and this will be of wide interest to those working in this field. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

  14. Data on the presence or absence of genes encoding essential proteins for ochratoxin and fumonisin biosynthesis in Aspergillus niger and Aspergillus welwitschiae

    Directory of Open Access Journals (Sweden)

    Fernanda Pelisson Massi

    2016-06-01

    Full Text Available 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 strains harboring the fum8 gene. Profile 4 (28% highlights strains not carrying the genes studied herein. This research content is supplemental to our original research article, “Prospecting for the incidence of genes involved in ochratoxin and fumonisin biosynthesis in Brazilian strains of A. niger and A. welwitschiae” [1].

  15. Proteolysis in tempeh-type products obtained with Rhizopus and Aspergillus strains from grass pea (Lathyrus sativus) seeds.

    Science.gov (United States)

    Starzyńska-Janiszewska, Anna; Stodolak, Bożena; Wikiera, Agnieszka

    2015-01-01

    Tempeh is a food product obtained from legumes by means of solid-state fermentation with Rhizopus sp. Our previous research proved that mixed-culture inoculum may also be successfully applied. The objective of present research was to study the proteolytic activity of R. microsporus var. chinensis and A. oryzae during tempeh-type fermentation of grass pea seeds, and the effect of inoculum composition on the protein level and in vitro protein bioavailability in products. Fermentation substrate were soaked and cooked grass pea seeds. Material was mixed with single- or mixed-culture inoculum, and incubated in perforated plastic bags at 30°C for 32 hrs. In the products, the proteolytic activity (pH 3, 5 and 7), glucosamine, total protein and free amino acids levels, as well as protein in vitro bioavailability and degree of protein hydrolysis were obtained. The significant correlation was found between glucosamine content and proteolytic activity in grass pea seeds fermented with Rhizopus or Aspergillus. The activities of Rhizopus proteases were higher than Aspergillus ones, which corresponded with the degree of seed protein hydrolysis. Both strains showed the highest activity of protease at pH 3. Tempeh made with pure culture of Rhizopus had 37% protein of 69% in-vitro bioavailability. Mixed-culture fermentation improved nutritional parameters of products only when the dose of Aspergillus spores in the inoculum was equal and lower than that of Rhizopus. This process resulted in higher in-vitro bioavailability of protein, slightly more efficient protein hydrolysis and higher level of free amino acids, as compared to standard tempeh. The activity of A. oryzae in tempeh-type fermentation is beneficial as long as it does not dominate the activity and/or growth of Rhizopus strain.

  16. Misidentification of Aspergillus nomius and Aspergillus tamarii as Aspergillus flavus: characterization by internal transcribed spacer, β-Tubulin, and calmodulin gene sequencing, metabolic fingerprinting, and matrix-assisted laser desorption ionization-time of flight mass spectrometry.

    Science.gov (United States)

    Tam, Emily W T; Chen, Jonathan H K; Lau, Eunice C L; Ngan, Antonio H Y; Fung, Kitty S C; Lee, Kim-Chung; Lam, Ching-Wan; Yuen, Kwok-Yung; Lau, Susanna K P; Woo, Patrick C Y

    2014-04-01

    Aspergillus nomius and Aspergillus tamarii are Aspergillus species that phenotypically resemble Aspergillus flavus. In the last decade, a number of case reports have identified A. nomius and A. tamarii as causes of human infections. In this study, using an internal transcribed spacer, β-tubulin, and calmodulin gene sequencing, only 8 of 11 clinical isolates reported as A. flavus in our clinical microbiology laboratory by phenotypic methods were identified as A. flavus. The other three isolates were A. nomius (n = 2) or A. tamarii (n = 1). The results corresponded with those of metabolic fingerprinting, in which the A. flavus, A. nomius, and A. tamarii strains were separated into three clusters based on ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC MS) analysis. The first two patients with A. nomius infections had invasive aspergillosis and chronic cavitary and fibrosing pulmonary and pleural aspergillosis, respectively, whereas the third patient had A. tamarii colonization of the airway. Identification of the 11 clinical isolates and three reference strains by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) showed that only six of the nine strains of A. flavus were identified correctly. None of the strains of A. nomius and A. tamarii was correctly identified. β-Tubulin or the calmodulin gene should be the gene target of choice for identifying A. flavus, A. nomius, and A. tamarii. To improve the usefulness of MALDI-TOF MS, the number of strains for each species in MALDI-TOF MS databases should be expanded to cover intraspecies variability.

  17. Misidentification of Aspergillus nomius and Aspergillus tamarii as Aspergillus flavus: Characterization by Internal Transcribed Spacer, β-Tubulin, and Calmodulin Gene Sequencing, Metabolic Fingerprinting, and Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry

    Science.gov (United States)

    Tam, Emily W. T.; Chen, Jonathan H. K.; Lau, Eunice C. L.; Ngan, Antonio H. Y.; Fung, Kitty S. C.; Lee, Kim-Chung; Lam, Ching-Wan; Yuen, Kwok-Yung

    2014-01-01

    Aspergillus nomius and Aspergillus tamarii are Aspergillus species that phenotypically resemble Aspergillus flavus. In the last decade, a number of case reports have identified A. nomius and A. tamarii as causes of human infections. In this study, using an internal transcribed spacer, β-tubulin, and calmodulin gene sequencing, only 8 of 11 clinical isolates reported as A. flavus in our clinical microbiology laboratory by phenotypic methods were identified as A. flavus. The other three isolates were A. nomius (n = 2) or A. tamarii (n = 1). The results corresponded with those of metabolic fingerprinting, in which the A. flavus, A. nomius, and A. tamarii strains were separated into three clusters based on ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC MS) analysis. The first two patients with A. nomius infections had invasive aspergillosis and chronic cavitary and fibrosing pulmonary and pleural aspergillosis, respectively, whereas the third patient had A. tamarii colonization of the airway. Identification of the 11 clinical isolates and three reference strains by matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) showed that only six of the nine strains of A. flavus were identified correctly. None of the strains of A. nomius and A. tamarii was correctly identified. β-Tubulin or the calmodulin gene should be the gene target of choice for identifying A. flavus, A. nomius, and A. tamarii. To improve the usefulness of MALDI-TOF MS, the number of strains for each species in MALDI-TOF MS databases should be expanded to cover intraspecies variability. PMID:24452174

  18. The Breeding of a Pigment Mutant Strain of Steroid Hydroxylation Aspergillus Flavus by Low Energy Ion Implantation

    International Nuclear Information System (INIS)

    Ye Hui; Ma Jingming; Feng Chun; Cheng Ying; Zhu Suwen; Cheng Beijiu

    2009-01-01

    In the process of the fermentation of steroid C 11 α-hydroxylgenation strain Aspergillus flavus AF-ANo208, a red pigment is derived, which will affect the isolation and purification of the target product. Low energy ion beam implantation is a new tool for breeding excellent mutant strains. In this study, the ion beam implantation experiments were performed by infusing two different ions: argon ion (Ar + ) and nitrogen ion (N + ). The results showed that the optimal ion implantation was N + with an optimum dose of 2.08 x 10 15 ions/cm 2 , with which the mutant strain AF-ANm16 that produced no red pigment was obtained. The strain had high genetic stability and kept the strong capacity of C11α-hydroxylgenation, which could be utilized in industrial fermentation. The differences between the original strain and the mutant strain at a molecular level were analyzed by randomly amplified polymorphic DNA (RAPD). The results indicated that the frequency of variation was 7.00%, which would establish the basis of application investigation into the breeding of pigment mutant strains by low energy ion implantation. (ion beam bioengineering)

  19. Insights from the genome of a high alkaline cellulase producing Aspergillus fumigatus strain obtained from Peruvian Amazon rainforest.

    Science.gov (United States)

    Paul, Sujay; Zhang, Angel; Ludeña, Yvette; Villena, Gretty K; Yu, Fengan; Sherman, David H; Gutiérrez-Correa, Marcel

    2017-06-10

    Here, we report the complete genome sequence of a high alkaline cellulase producing Aspergillus fumigatus strain LMB-35Aa isolated from soil of Peruvian Amazon rainforest. The genome is ∼27.5mb in size, comprises of 228 scaffolds with an average GC content of 50%, and is predicted to contain a total of 8660 protein-coding genes. Of which, 6156 are with known function; it codes for 607 putative CAZymes families potentially involved in carbohydrate metabolism. Several important cellulose degrading genes, such as endoglucanase A, endoglucanase B, endoglucanase D and beta-glucosidase, are also identified. The genome of A. fumigatus strain LMB-35Aa represents the first whole sequenced genome of non-clinical, high cellulase producing A. fumigatus strain isolated from forest soil. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. A glycoprotein with anti-inflammatory properties secreted by an Aspergillus nidulans modified strain

    Directory of Open Access Journals (Sweden)

    J. C. F. Queiroz

    2007-01-01

    Full Text Available Total RNA from lipopolysaccharide (LPS-stimulated rat macrophages used to treat protoplasts from an Aspergillus nidulans strain originated the RT2 regenerated strain, whose culture supernatant showed anti-inflammatory activity in Wistar rats. The protein fraction presenting such anti-inflammatory activity was purified and biochemically identified. The screening of the fraction responsible for such anti-inflammatory property was performed by evaluating the inhibition of carrageenan-induced paw edema in male Swiss mice. Biochemical analyses of the anti-inflammatory protein used chromatography, carbohydrates quantification of the protein sample, amino acids content analysis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE. Total sugar quantification revealed 32% glycosylation of the protein fraction. Amino acid analysis of such fraction showed a peculiar pattern presenting 29% valine. SDS-PAGE revealed that the protein sample is pure and its molecular weight is about 40kDa. Intravenous injection of the isolated substance into mice significantly inhibited carrageenan-induced paw edema. The isolated glycoprotein decreased carrageenan-induced paw edema in a prostaglandin-dependent phase, suggesting an inhibitory effect of the isolated glycoprotein on prostaglandin synthesis.

  1. Overexpression of Aspergillus tubingensis faeA in protease-deficient Aspergillus niger enables ferulic acid production from plant material.

    Science.gov (United States)

    Zwane, Eunice N; Rose, Shaunita H; van Zyl, Willem H; Rumbold, Karl; Viljoen-Bloom, Marinda

    2014-06-01

    The production of ferulic acid esterase involved in the release of ferulic acid side groups from xylan was investigated in strains of Aspergillus tubingensis, Aspergillus carneus, Aspergillus niger and Rhizopus oryzae. The highest activity on triticale bran as sole carbon source was observed with the A. tubingensis T8.4 strain, which produced a type A ferulic acid esterase active against methyl p-coumarate, methyl ferulate and methyl sinapate. The activity of the A. tubingensis ferulic acid esterase (AtFAEA) was inhibited twofold by glucose and induced twofold in the presence of maize bran. An initial accumulation of endoglucanase was followed by the production of endoxylanase, suggesting a combined action with ferulic acid esterase on maize bran. A genomic copy of the A. tubingensis faeA gene was cloned and expressed in A. niger D15#26 under the control of the A. niger gpd promoter. The recombinant strain has reduced protease activity and does not acidify the media, therefore promoting high-level expression of recombinant enzymes. It produced 13.5 U/ml FAEA after 5 days on autoclaved maize bran as sole carbon source, which was threefold higher than for the A. tubingensis donor strain. The recombinant AtFAEA was able to extract 50 % of the available ferulic acid from non-pretreated maize bran, making this enzyme suitable for the biological production of ferulic acid from lignocellulosic plant material.

  2. Variability in Galactomannan detection by platelia Aspergillus EIA™ according to the Aspergillus species Variabilidade na detecção de galactomanana pelo Platelia Aspergillus EIA® de acordo com a espécie de Aspergillus

    Directory of Open Access Journals (Sweden)

    Melissa Orzechowski Xavier

    2013-06-01

    Full Text Available Here we investigate the extent to which different Aspergillus species release galactomannan (GM in vitro. Marked variability was observed in GM reactivity between and within Aspergillus species, with A. terreus strains showing the highest GM indexes. The in vivo significance of these findings remains to be determined.O estudo objetivou investigar a liberação in vitro de galactomanana (GM em distintas espécies patogênicas de fungos do gênero Aspergillus. Grande variabilidade foi detectada tanto intra quanto inter espécies, sendo as cepas da espécie A. terreus relacionadas aos maiores índices de GM detectados. O significado in vivo destes achados permanece em aberto, porém merece investigação.

  3. Biocontrol activity of four non- and low-fermenting yeast strains against Aspergillus carbonarius and their ability to remove ochratoxin A from grape juice.

    Science.gov (United States)

    Fiori, Stefano; Urgeghe, Pietro Paolo; Hammami, Walid; Razzu, Salvatorico; Jaoua, Samir; Migheli, Quirico

    2014-10-17

    Aspergillus spp. infection of grape may lead to ochratoxin A (OTA) contamination in processed beverages such as wine and grape juice. The aim of the current study was to evaluate the biocontrol potential of two non-fermenting (Cyberlindnera jadinii 273 and Candida friedrichii 778) and two low-fermenting (Candida intermedia 235 and Lachancea thermotolerans 751) yeast strains against the pathogenic fungus and OTA-producer Aspergillus carbonarius, and their ability to remove OTA from grape juice. Two strains, 235 and 751, showed a significant ability to inhibit A. carbonarius both on grape berries and in in vitro experiments. Neither their filtrate nor their autoclaved filtrate culture broth was able to prevent consistently pathogen growth. Volatile organic compounds (VOCs) produced by all four selected yeasts were likely able to consistently prevent pathogen sporulation in vitro. VOCs produced by the non-fermenting strain 778 also significantly reduced A. carbonarius vegetative growth. Three yeast strains (235, 751, and 778) efficiently adsorbed artificially spiked OTA from grape juice, while autoclaving treatment improved OTA adsorption capacity by all the four tested strains. Biological control of A. carbonarius and OTA-decontamination using yeast is proposed as an approach to meet the Islamic dietary laws concerning the absence of alcohol in halal beverages. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  4. Malic acid production from thin stillage by Aspergillus species.

    Science.gov (United States)

    West, Thomas P

    2011-12-01

    The ability of Aspergillus strains to utilize thin stillage to produce malic acid was compared. The highest malic acid was produced by Aspergillus niger ATCC 9142 at 17 g l(-1). Biomass production from thin stillage was similar with all strains but ATCC 10577 was the highest at 19 g l(-1). The highest malic acid yield (0.8 g g(-1)) was with A. niger ATCC 9142 and ATCC 10577 on the stillage. Thus, thin stillage has the potential to act as a substrate for the commercial production of food-grade malic acid by the A. niger strains. © Springer Science+Business Media B.V. 2011

  5. The Inhibition of aflatoxin production from Aspergillus parasiticus ...

    African Journals Online (AJOL)

    The inhibition of Aflatoxin production from Aspergillus parasiticus strain NRRL 2999 was investigated using ethanol extracts of Aframommon danielli flower at concentrations of 250ìg/g, 500ìg/g, 750ìg/g and 1000ìg/g with whole wheat bread as a substrate. Aspergillus parasiticus grew abundantly on whole wheat bread; ...

  6. screening and improvement of local isolates of aspergillus niger

    African Journals Online (AJOL)

    DR. AMINU

    ABSTRACT. The study involved the screening of fourteen isolates of Aspergillus niger for citric acid production from glucose. The study was aimed at screening and improving local strains of Aspergillus niger with potential for citric acid production. All the isolates screened produced varying amounts of citric acid, the highest ...

  7. Dose effect of the uvsA+ gene product in duplication strains of Aspergillus nidulans

    International Nuclear Information System (INIS)

    Majerfeld, I.H.; Roper, J.A.

    1978-01-01

    Strains of Aspergillus nidulans which carry a particular segment of chromosome I in duplicate - one segment in normal position, the other translocated to chromosome II - are more resistant to uv light than are strains with a balanced haploid genome. A double dose of the uvsA + allele, carried on the duplicate segment, determines this enhanced resistance; this is shown by the descending order of resistance of duplication haploids uvsA + /uvsA + , uvsA1/uvsA + and uvsA1/uvsA1. An unbalanced diploid with three doses of the uvsA + allele also shows greater resistance than a balanced uvsA + //uvsA + diploid. However, in balanced diploids the uvsA1 allele appears to be completely recessive; uvsA + //uvsA + and uvsA + //uvsA1 diploids produce indistinguishable survival curves after uv irradiation. Thus, the uvsA + gene product is not rate-limiting in repair processes in strains with a balanced genome. The rate-limiting effect observed in these unbalanced strains presumably reflects an interaction of the uvsA + product and other functions determined by the rest of the genome. Duplication haploids and normal haploids lose photorepairable lesions at similar rates. This observation may be interpreted to indicate that differences in survival are not due to differences in the efficiency of excision of uv-induced pyrimidime dimers

  8. Arabidopsis thaliana defense response to the ochratoxin A-producing strain (Aspergillus ochraceus 3.4412).

    Science.gov (United States)

    Hao, Junran; Wu, Weihong; Wang, Yan; Yang, Zhuojun; Liu, Yang; Lv, Yangjun; Zhai, Yanan; Yang, Jing; Liang, Zhihong; Huang, Kunlun; Xu, Wentao

    2015-05-01

    OTA-producing strain Aspergillus ochraceus induced necrotic lesions, ROS accumulation and defense responses in Arabidopsis . Primary metabolic and defense-related proteins changed in proteomics. Ascorbate-glutathione cycle and voltage-dependent anion-selective channel proteins fluctuated. Mycotoxigenic fungi, as widespread contaminants by synthesizing mycotoxins in pre-/post-harvest infected plants and even stored commercial cereals, could usually induce plant-fungi defense responses. Notably, ochratoxin A (OTA) is a nephrotoxic, hepatotoxic, teratogenic, immunotoxic and phytotoxic mycotoxin. Herein, defense responses of model system Arabidopsis thaliana detached leaves to infection of Aspergillus ochraceus 3.4412, an OTA high-producing strain, were studied from physiological, proteomic and transcriptional perspectives. During the first 72 h after inoculation (hai), the newly formed hypersensitive responses-like lesions, decreased chlorophyll content, accumulated reactive oxygen species and upregulated defense genes expressions indicated the defense response was induced in the leaves with the possible earlier motivated jasmonic acid/ethylene signaling pathways and the later salicylic acid-related pathway. Moreover, proteomics using two-dimensional gel electrophoresis 72 hai showed 16 spots with significantly changed abundance and 13 spots corresponding to 12 unique proteins were successfully identified by MALDI-TOF/TOF MS/MS. Of these, six proteins were involved in basic metabolism and four in defense-related processes, which included glutathione-S-transferase F7, voltage-dependent anion-selective channel protein 3 (VDAC-3), osmotin-like protein OSM34 and blue copper-binding protein. Verified from proteomic and/or transcriptional perspectives, it is concluded that the primary metabolic pathways were suppressed with the ascorbate-glutathione cycle fluctuated in response to A. ochraceus and the modulation of VDACs suggested the possibility of structural damage and

  9. Induction of Aspergillus oryzae mutant strains producing increased levels of α-amylase by gamma-irradiation

    International Nuclear Information System (INIS)

    Ito, Hitoshi; Nessa, Azizun

    1996-01-01

    Spores of Aspergillus oryzae IAM 2630 were suspended in 0.067 m phosphate buffer and irradiated with gamma rays. Spores were incubated for 7 days and colony mutants counted by observing colour change compared to normal colours. α-amylase activities of the normal and mutant colonies were assayed. DNA assay of the spores was also carried out, after culture on different plating media. Enzyme production increased 2-5 times with increasing radiation dose. Increased spore size and DNA content was also observed in mutant strains with higher enzyme production suggesting that enzyme production is genetically controlled. Ultraviolet radiation did not appear to induce higher frequency of mutation. (UK)

  10. Induction of Aspergillus oryzae mutant strains producing increased levels of {alpha}-amylase by gamma-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Hitoshi; Nessa, Azizun [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1996-12-01

    Spores of Aspergillus oryzae IAM 2630 were suspended in 0.067 m phosphate buffer and irradiated with gamma rays. Spores were incubated for 7 days and colony mutants counted by observing colour change compared to normal colours. {alpha}-amylase activities of the normal and mutant colonies were assayed. DNA assay of the spores was also carried out, after culture on different plating media. Enzyme production increased 2-5 times with increasing radiation dose. Increased spore size and DNA content was also observed in mutant strains with higher enzyme production suggesting that enzyme production is genetically controlled. Ultraviolet radiation did not appear to induce higher frequency of mutation. (UK).

  11. Causative Agents of Aspergillosis Including Cryptic Aspergillus Species and A. fumigatus.

    Science.gov (United States)

    Toyotome, Takahito

    2016-01-01

    Aspergillosis is an important deep mycosis. The causative agents are Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, and Aspergillus terreus, of which A. fumigatus is the most prevalent. Cryptic Aspergillus spp., which morphologically resemble representative species of each Aspergillus section, also cause aspergillosis. Most of the cryptic species reveal different susceptibility patterns and/or different secondary metabolite profiles, also called exometabolome in this manuscript, from those representative species. On the other hand, azole-resistant A. fumigatus strains in clinical specimens and in the environment have been reported. Therefore, it is imperative to precisely identify the species, including cryptic Aspergillus spp., and evaluate the susceptibility of isolates.In this manuscript, some of the causative cryptic Aspergillus spp. are briefly reviewed. In addition, the exometabolome of Aspergillus section Fumigati is described. Finally, azole resistance of A. fumigatus is also discussed, in reference to several studies from Japan.

  12. Volatiles Mediated Interactions Between Aspergillus oryzae Strains Modulate Morphological Transition and Exometabolomes.

    Science.gov (United States)

    Singh, Digar; Lee, Choong H

    2018-01-01

    Notwithstanding its mitosporic nature, an improbable morpho-transformation state i. e., sclerotial development (SD), is vaguely known in Aspergillus oryzae . Nevertheless an intriguing phenomenon governing mold's development and stress response, the effects of exogenous factors engendering SD, especially the volatile organic compounds (VOCs) mediated interactions (VMI) pervasive in microbial niches have largely remained unexplored. Herein, we examined the effects of intra-species VMI on SD in A. oryzae RIB 40, followed by comprehensive analyses of associated growth rates, pH alterations, biochemical phenotypes, and exometabolomes. We cultivated A. oryzae RIB 40 (S1 VMI : KACC 44967) opposite a non-SD partner strain, A. oryzae (S2: KCCM 60345), conditioning VMI in a specially designed "twin plate assembly." Notably, SD in S1 VMI was delayed relative to its non-conditioned control (S1) cultivated without partner strain (S2) in twin plate. Selectively evaluating A. oryzae RIB 40 (S1 VMI vs. S1) for altered phenotypes concomitant to SD, we observed a marked disparity for corresponding growth rates (S1 VMI S1) 7days , and biochemical characteristics viz ., protease (S1 VMI > S1) 7days , amylase (S1 VMI > nS1) 3-7 days , and antioxidants (S1 VMI > S1) 7days levels. The partial least squares-discriminant analysis (PLS-DA) of gas chromatography-time of flight-mass spectrometry (GC-TOF-MS) datasets for primary metabolites exhibited a clustered pattern (PLS1, 22.04%; PLS2, 11.36%), with 7 days incubated S1 VMI extracts showed higher abundance of amino acids, sugars, and sugar alcohols with lower organic acids and fatty acids levels, relative to S1. Intriguingly, the higher amino acid and sugar alcohol levels were positively correlated with antioxidant activity, likely impeding SD in S1 VMI . Further, the PLS-DA (PLS1, 18.11%; PLS2, 15.02%) based on liquid chromatography-mass spectrometry (LC-MS) datasets exhibited a notable disparity for post-SD (9-11 days) sample extracts

  13. Volatiles Mediated Interactions Between Aspergillus oryzae Strains Modulate Morphological Transition and Exometabolomes

    Directory of Open Access Journals (Sweden)

    Digar Singh

    2018-04-01

    Full Text Available Notwithstanding its mitosporic nature, an improbable morpho-transformation state i. e., sclerotial development (SD, is vaguely known in Aspergillus oryzae. Nevertheless an intriguing phenomenon governing mold's development and stress response, the effects of exogenous factors engendering SD, especially the volatile organic compounds (VOCs mediated interactions (VMI pervasive in microbial niches have largely remained unexplored. Herein, we examined the effects of intra-species VMI on SD in A. oryzae RIB 40, followed by comprehensive analyses of associated growth rates, pH alterations, biochemical phenotypes, and exometabolomes. We cultivated A. oryzae RIB 40 (S1VMI: KACC 44967 opposite a non-SD partner strain, A. oryzae (S2: KCCM 60345, conditioning VMI in a specially designed “twin plate assembly.” Notably, SD in S1VMI was delayed relative to its non-conditioned control (S1 cultivated without partner strain (S2 in twin plate. Selectively evaluating A. oryzae RIB 40 (S1VMI vs. S1 for altered phenotypes concomitant to SD, we observed a marked disparity for corresponding growth rates (S1VMI < S17days, media pH (S1VMI > S17days, and biochemical characteristics viz., protease (S1VMI > S17days, amylase (S1VMI > nS13–7days, and antioxidants (S1VMI > S17days levels. The partial least squares—discriminant analysis (PLS-DA of gas chromatography—time of flight—mass spectrometry (GC-TOF-MS datasets for primary metabolites exhibited a clustered pattern (PLS1, 22.04%; PLS2, 11.36%, with 7 days incubated S1VMI extracts showed higher abundance of amino acids, sugars, and sugar alcohols with lower organic acids and fatty acids levels, relative to S1. Intriguingly, the higher amino acid and sugar alcohol levels were positively correlated with antioxidant activity, likely impeding SD in S1VMI. Further, the PLS-DA (PLS1, 18.11%; PLS2, 15.02% based on liquid chromatography—mass spectrometry (LC-MS datasets exhibited a notable disparity for post-SD (9

  14. Aspergillus brasiliensis sp. nov., a biseriate black Aspergillus species with world-wide distribution

    DEFF Research Database (Denmark)

    Varga, János; Kocsubé, Sándor; Tóth, Beáta

    2007-01-01

    to produce ochratoxin A, kotanins, funalenone or pyranonigrins. The novel species was most closely related to A. niger, and was isolated from soil from Brazil, Australia, USA and The Netherlands, and from grape berries from Portugal. The type strain of Aspergillus brasiliensis sp. nov. is CBS 101740(T) (=IM...

  15. Expression of the Aspergillus terreus itaconic acid biosynthesis cluster in Aspergillus niger.

    Science.gov (United States)

    van der Straat, Laura; Vernooij, Marloes; Lammers, Marieke; van den Berg, Willy; Schonewille, Tom; Cordewener, Jan; van der Meer, Ingrid; Koops, Andries; de Graaff, Leo H

    2014-01-17

    Aspergillus terreus is a natural producer of itaconic acid and is currently used to produce itaconic acid on an industrial scale. The metabolic process for itaconic acid biosynthesis is very similar to the production of citric acid in Aspergillus niger. However, a key enzyme in A. niger, cis-aconitate decarboxylase, is missing. The introduction of the A. terreus cadA gene in A. niger exploits the high level of citric acid production (over 200 g per liter) and theoretically can lead to production levels of over 135 g per liter of itaconic acid in A. niger. Given the potential for higher production levels in A. niger, production of itaconic acid in this host was investigated. Expression of Aspergillus terreus cis-aconitate decarboxylase in Aspergillus niger resulted in the production of a low concentration (0.05 g/L) of itaconic acid. Overexpression of codon-optimized genes for cis-aconitate decarboxylase, a mitochondrial transporter and a plasma membrane transporter in an oxaloacetate hydrolase and glucose oxidase deficient A. niger strain led to highly increased yields and itaconic acid production titers. At these higher production titers, the effect of the mitochondrial and plasma membrane transporters was much more pronounced, with levels being 5-8 times higher than previously described. Itaconic acid can be produced in A. niger by the introduction of the A. terreus cis-aconitate decarboxylase encoding cadA gene. This results in a low itaconic acid production level, which can be increased by codon-optimization of the cadA gene for A. niger. A second crucial requirement for efficient production of itaconic acid is the expression of the A. terreus mttA gene, encoding a putative mitochondrial transporter. Expression of this transporter results in a twenty-fold increase in the secretion of itaconic acid. Expression of the A. terreus itaconic acid cluster consisting of the cadA gene, the mttA gene and the mfsA gene results in A. niger strains that produce over

  16. Biological control of post harvest disease caused by Aspergillus ...

    African Journals Online (AJOL)

    Antagonistic activity of 24 selected bacterial strains detected by previous microbiological studies to Aspergillus flavus was tested in vitro and in vivo conditions. Within 24 strains, only ten strains showed remarkable inhibition zone (6-34 mm) against the pathogen in assays carried out in Petri plates. Both cell suspension and ...

  17. Cloning and Genomic Organization of a Rhamnogalacturonase Gene from Locally Isolated Strain of Aspergillus niger.

    Science.gov (United States)

    Damak, Naourez; Abdeljalil, Salma; Taeib, Noomen Hadj; Gargouri, Ali

    2015-08-01

    The rhg gene encoding a rhamnogalacturonase was isolated from the novel strain A1 of Aspergillus niger. It consists of an ORF of 1.505 kb encoding a putative protein of 446 amino acids with a predicted molecular mass of 47 kDa, belonging to the family 28 of glycosyl hydrolases. The nature and position of amino acids comprising the active site as well as the three-dimensional structure were well conserved between the A. niger CTM10548 and fungal rhamnogalacturonases. The coding region of the rhg gene is interrupted by three short introns of 56 (introns 1 and 3) and 52 (intron 2) bp in length. The comparison of the peptide sequence with A. niger rhg sequences revealed that the A1 rhg should be an endo-rhamnogalacturonases, more homologous to rhg A than rhg B A. niger known enzymes. The comparison of rhg nucleotide sequence from A. niger A1 with rhg A from A. niger shows several base changes. Most of these changes (59 %) are located at the third base of codons suggesting maintaining the same enzyme function. We used the rhamnogalacturonase A from Aspergillus aculeatus as a template to build a structural model of rhg A1 that adopted a right-handed parallel β-helix.

  18. PENGARUH RHIZOPUS ORYZAE DAN ASPERGILLUS ORYZAE TERHADAP KUALITAS KECAP

    Directory of Open Access Journals (Sweden)

    Dewi Sabita Slamet

    2012-11-01

    Full Text Available Telah diteliti pengganti fermentasi mikroorganisme Aspergillus oryzae Rhyzopus oryzae dan campuran Aspergillus dan Rhyzopus oryzae, dengan perendaman dalam larutan garam 20% dalam waktu yang berbeda terhadap kualitas kecap.Lamanya perendaman dalam larutan garam 20% yang berbeda menghasilkan kadar protein kecap yang berbeda. Aspergillus oryzae lebih baik dalam menghasilkan enzima protease dari pada Rhyzopus oryzae.Uji organoleptik menunjukkan perbedaan tidak bermakna dalam hal rasa maupun aroma antar kecap yang dibuat dengan strain jamur yang berlainan serta waktu perendaman yang berbeda. Untuk membuat kecap, sebaiknya dilakukan perendaman dalam larutan garam 20% selama 14 hari.

  19. Biotransformation of L-tyrosine to Dopamine by a Calcium Alginate Immobilized Mutant Strain of Aspergillus oryzae.

    Science.gov (United States)

    Ali, Sikander; Nawaz, Wajeeha

    2016-08-01

    The present research work is concerned with the biotransformation of L-tyrosine to dopamine (DA) by calcium alginate entrapped conidiospores of a mutant strain of Aspergillus oryzae. Different strains of A. oryzae were isolated from soil. Out of 13 isolated strains, isolate-2 (I-2) was found to be a better DA producer. The wild-type I-2 was chemically improved by treating it with different concentrations of ethyl methyl sulfonate (EMS). Among seven mutant variants, EMS-6 exhibiting maximal DA activity of 43 μg/ml was selected. The strain was further exposed with L-cysteine HCl to make it resistant against diversion and environmental stress. The conidiospores of selected mutant variant A. oryzae EMS-6 strain were entrapped in calcium alginate beads. Different parameters for immobilization were investigated. The activity was further improved from 44 to 62 μg/ml under optimized conditions (1.5 % sodium alginate, 2 ml inoculum, and 2 mm bead size). The best resistant mutant variable exhibited over threefold increase in DA activity (62 μg/ml) than did wild-type I-2 (21 μg/ml) in the reaction mixture. From the results presented in the study, it was observed that high titers of DA activity in vitro could effectively be achieved by the EMS-induced mutagenesis of filamentous fungus culture used.

  20. Deletion of a Chitin Synthase Gene in a Citric Acid Producing Strain of Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Rinker, Torri E.; Baker, Scott E.

    2007-01-29

    Citric acid production by the filamentous fungus Aspergillus niger is carried out in a process that causes the organism to drastically alter its morphology. This altered morphology includes hyphal swelling and highly limited polar growth resulting in clumps of swollen cells that eventually aggregate into pellets of approximately 100 microns in diameter. In this pelleted form, A. niger has increased citric acid production as compared to growth in filamentous form. Chitin is a crucial component of the cell wall of filamentous fungi. Alterations in the deposition or production of chitin may have profound effects on the morphology of the organism. In order to study the role of chitin synthesis in pellet formation we have deleted a chitin synthase gene (csmA) in Aspergillus niger strain ATCC 11414 using a PCR based deletion construct. This class of chitin synthases is only found in filamentous fungi and is not present in yeasts. The csmA genes contain a myosin motor domain at the N-terminus and a chitin synthesis domain at the C-terminus. They are believed to contribute to the specialized polar growth observed in filamentous fungi that is lacking in yeasts. The csmA deletion strain (csmAΔ) was subjected to minimal media with and without osmotic stabilizers as well as tested in citric acid production media. Without osmotic stabilizers, the mutant germlings were abnormally swollen, primarily in the subapical regions, and contained large vacuoles. However, this swelling is ultimately not inhibitory to growth as the germlings are able to recover and undergo polar growth. Colony formation was largely unaffected in the absence of osmotic stabilizers. In citric acid production media csmAΔ was observed to have a 2.5 fold increase in citric acid production. The controlled expression of this class of chitin synthases may be useful for improving production of organic acids in filamentous fungi.

  1. Aspergillus mulundensis sp. nov., a new species for the fungus producing the antifungal echinocandin lipopeptides, mulundocandins

    DEFF Research Database (Denmark)

    Bills, Gerald F.; Yue, Qun; Chen, Li

    2016-01-01

    The invalidly published name Aspergillus sydowii var. mulundensis was proposed for a strain of Aspergillus that produced new echinocandin metabolites designated as the mulundocadins. Reinvestigation of this strain (Y-30462=DSMZ 5745) using phylogenetic, morphological, and metabolic data indicated...

  2. Volatile metabolites associated with one aflatoxigenic and one nontoxigenic Aspergillus flavus strain grown on two different substrates

    Directory of Open Access Journals (Sweden)

    Z. Jurjevic

    2009-01-01

    Full Text Available Aflatoxigenic and non-toxigenic Aspergillus flavus strains were grown on corn and on peanut substrates. Microbial volatile organic compounds (MVOCS were collected by trapping headspace volatiles using thermal desorption tubes (TDT packed with Tenax® TA and Carbotrap™ B. Samples were collected at various fungal growth stages. Trapped compounds were thermally desorbed from the adsorbent tubes, separated by gas chromatography, and identified by mass spectrometry. The fungal stage did not have many differences in the MVOCs but the concentrations of some volatiles changed over time depending on the substrate. Volatiles that were associated with both the aflatoxigenic A. flavus strain and the nontoxigenic strain on both substrates included: ethanol, 1-propanol, butanal, 2-methyl-1-propanol, 3-methylfuran, ethyl acetate, 1-butanol, 3-methylbutanal, 3-methyl-1-butanol, propanoic acid-2-methyl-ethyl-ester, 2-methyl-1-butanol, 1-pentanol, 2-pentanol, 3-methyl-3-buten-1-ol, benzaldehyde, 3-octanone, 2-ethyl-1-hexanol and octane. Volatiles that were associated only with the aflatoxigenic A. flavus strain included: dimethyl disulfide and nonanal. Volatiles that were associated only with the nontoxigenic A. fl avus strain included: hexanal, 1-hexanol, 1-octene-3-ol, 1-octen-3-one and 2-pentyl furan.

  3. ALPHA-AMYLASE PRODUCTION FROM Aspergillus oryzae M BY SUBMERGED FERMENTATION

    Directory of Open Access Journals (Sweden)

    Suleimenova

    2016-08-01

    Full Text Available The main goal of present study was implementation of the Aspergillus oryzae M strain improved technology using earlier developed method of microorganism selection. 8 pure strains of Aspergillus fungi were screened for the production of extra cellular alpha-amylase using agar medium with starch as a substrate and incubated for 72h at 30 ºС. Zone of clearance was observed for screening of the amylolytic fungi (in mm. Aspergillus oryzae M has demonstrated the highest zone of clearance. Aspergillus oryzae M was cultivated for 42 days in submerged conditions of growth using new method of fungal cultivation. This method based on immobilizing enzymes producers on solid career in submerged conditions of growth gives the way to improve quality of filtrates, which remain clear, does not require additional filtering and easily separated from the mycelium. Moreover, it allows to prolong the process of fungal cultivation and to maintain high enzymatic activity for a long period of time. Presented method allowed increasing alpha-amylase production from 321 U/ml (before immobilization to 502 U/ml (after immobilization.

  4. Process optimization for a potent wild and mutant strain of aspergillus niger for biosynthesis of amyloglucosidase

    International Nuclear Information System (INIS)

    Malik, S.; Haq, I.U.; Iftikhar, T.

    2011-01-01

    The present study is concerned with the selection of a potent strain of Aspergillus niger and optimization of the cultural conditions for the biosynthesis of amyloglucosidase. The cultural conditions were optimized for the enzyme production. Twenty percent (50/250ml flask) was found to be optimum volume of the medium. Optimum temperature was 30 deg. C after 72 h of incubation, with the initial pH of the medium 5.0. 2% Starch with 1% glucose as an additional carbon source gave maximum amyloglucosidase production Addition of 0.3% ammonium sulphate in the fermentation medium increased the enzyme production while 2% spore inoculum showed best amyloglucosidase production. (author)

  5. Fumonisins in Aspergillus niger: Industrial and food aspects

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian; Nielsen, Kristian Fog; Mogensen, Jesper

    Introduction: Fumonisins are toxic seconday metabolites from Fusarium verticillioides and other Fusaria, from Tolypocladium and Aspergillus niger 1,2. Being a generalist Aspergillus niger is the workhorse in a very large number of industrial applications, and is also a common contaminant in foods....... Fumonisin production by A. niger is depending on temperature and water activity, but is produced mostly on substrates with high maounts of sugar or salt 1,3,4. We wanted to find out whether industrial strains could produce fumonisins in worst case scenarios and if fumonisin production was only a feature...... ever used in biotechnology could produce fuminisins B2, B4 & B6. The strains could be subdivided into two clades (representing A. niger and the “phylospecies” A. awamori), and there were fumonisin producers in both clades. Ochratoxin A was also produced by strains in both clades, but only...

  6. High-yields heterologous production of the novel Aspergillus fumigatus elastase inhibitor AFUEI in Aspergillus oryzae.

    Science.gov (United States)

    Yamashita, Nobuo; Komori, Yumiko; Okumura, Yoshiyuki; Uchiya, Kei-Ichi; Matsui, Takeshi; Nishimura, Akira; Ogawa, Kenji; Nikai, Toshiaki

    2011-08-01

    AFUEI, an elastase inhibitor produced by Aspergillus fumigatus strongly inhibits the elastolytic activity of A. fumigatus etc. To purify AFUEI, we constructed a strain that overproduces AFUEI by introducing the gene encoding AFUEI (Genbank accession no. AB546725) under control of the amyB promoter into the heterologous host Aspergillus oryzae. A. oryzae TF-4 displayed strong elastase inhibitory activity and produced considerably more AFUEI than that of A. fumigatus. Furthermore, AFUEI could be purified using culture broth and single ultrafiltration (UF) treatment, allowing for the effective production of AFUEI for use in clinical trials. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  7. Unique antimicrobial spectrum of ophiobolin K produced by Aspergillus ustus.

    Science.gov (United States)

    Sohsomboon, Natthapat; Kanzaki, Hiroshi; Nitoda, Teruhiko

    2018-03-01

    A co-cultivation study of two fungal strains showed that Aspergillus ustus could inhibit Aspergillus repens growth. The bioactive compound responsible for the observed activity was purified and identified as a sesterterpene, ophiobolin K. Ophiobolin K exhibited marked inhibition against both fungi and bacteria, especially A. repens, A. glaucus and gram-positive bacteria including Bacillus subtilis, Staphylococcus aureus, and Micrococcus luteus.

  8. Proteomics of eukaryotic microorganisms: The medically and biotechnologically important fungal genus Aspergillus.

    Science.gov (United States)

    Kniemeyer, Olaf

    2011-08-01

    Fungal species of the genus Aspergillus play significant roles as model organisms in basic research, as "cell factories" for the production of organic acids, pharmaceuticals or industrially important enzymes and as pathogens causing superficial and invasive infections in animals and humans. The release of the genome sequences of several Aspergillus sp. has paved the way for global analyses of protein expression in Aspergilli including the characterisation of proteins, which have not designated any function. With the application of proteomic methods, particularly 2-D gel and LC-MS/MS-based methods, first insights into the composition of the proteome of Aspergilli under different growth and stress conditions could be gained. Putative targets of global regulators led to the improvement of industrially relevant Aspergillus strains and so far not described Aspergillus antigens have already been discovered. Here, I review the recent proteome data generated for the species Aspergillus nidulans, Aspergillus fumigatus, Aspergillus niger, Aspergillus terreus, Aspergillus flavus and Aspergillus oryzae. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Optimization of liquid-state fermentation conditions for the glyphosate degradation enzyme production of strain Aspergillus oryzae by ultraviolet mutagenesis.

    Science.gov (United States)

    Fu, Gui-Ming; Li, Ru-Yi; Li, Kai-Min; Hu, Ming; Yuan, Xiao-Qiang; Li, Bin; Wang, Feng-Xue; Liu, Cheng-Mei; Wan, Yin

    2016-11-16

    This study aimed to obtain strains with high glyphosate-degrading ability and improve the ability of glyphosate degradation enzyme by the optimization of fermentation conditions. Spore from Aspergillus oryzae A-F02 was subjected to ultraviolet mutagenesis. Single-factor experiment and response surface methodology were used to optimize glyphosate degradation enzyme production from mutant strain by liquid-state fermentation. Four mutant strains were obtained and named as FUJX 001, FUJX 002, FUJX 003, and FUJX 004, in which FUJX 001 gave the highest total enzyme activity. Starch concentration at 0.56%, GP concentration at 1,370 mg/l, initial pH at 6.8, and temperature at 30°C were the optimum conditions for the improved glyphosate degradation endoenzyme production of A. oryzae FUJX 001. Under these conditions, the experimental endoenzyme activity was 784.15 U/100 ml fermentation liquor. The result (784.15 U/100 ml fermentation liquor) was approximately 14-fold higher than that of the original strain. The result highlights the potential of glyphosate degradation enzyme to degrade glyphosate.

  10. Production and partial purification of glucoamylase from Aspergillus ...

    African Journals Online (AJOL)

    Glucoamylase is an enzyme that hydrolyses 1,4α and 1,6β-glucosidic linkages in polysaccharides yielding glucose. Aspergillus niger strains 1, 2 and 3 were locally isolated from cassava peel dumpsite for the production of glucoamylase enzyme. A. niger strains 1, 2 and 3 were screened for their hyper producing ability on ...

  11. Chemometric analysis of in-line multi-wavelength fluorescence measurements obtained during cultivations with a lipase producing Aspergillus oryzae strain

    DEFF Research Database (Denmark)

    Haack, Martin Brian; Eliasson Lantz, Anna; Mortensen, P.P.

    2007-01-01

    The filamentous fungus, Aspergillus oryzae, was cultivated in batch and fed-batch cultivations in order to investigate the use of multi-wavelength fluorescence for monitoring course of events during filamentous fungi cultivations. The A. oryzae strain applied expressed a fungal lipase from...... Thermomyces lanuginosus. Spectra of multi-wavelength fluorescence were collected every 5 min with the BioView system (DELTA, Denmark) and both explorative and predictive models, correlating the fluorescence data with cell mass and lipase activity, were built. During the cultivations, A. oryzae displayed...

  12. Aspergillus Associated with Meju, a Fermented Soybean Starting Material for Traditional Soy Sauce and Soybean Paste in Korea.

    Science.gov (United States)

    Hong, Seung-Beom; Kim, Dae-Ho; Samson, Robert A

    2015-09-01

    Aspergillus is an important fungal genus used for the fermentation of Asian foods; this genus is referred to as koji mold in Japan and China. A. oryzae, A. sojae, and A. tamari are used in the production of miso and shoyu in Japan, but a comprehensive taxonomic study of Aspergillus isolated from Meju, a fermented soybean starting material for traditional soy sauce and soybean paste in Korea, has not been conducted. In this study, various Aspergillus species were isolated during a study of the mycobiota of Meju, and the aspergilli were identified based on phenotypic characteristics and sequencing of the β-tubulin gene. Most strains of Aspergillus were found to belong to the following sections: Aspergillus (n = 220), Flavi (n = 213), and Nigri (n = 54). The most commonly identified species were A. oryzae (n = 183), A. pseudoglaucus (Eurotium repens) (n = 81), A. chevalieri (E. chevalieri) (n = 62), A. montevidensis (E. amstelodami) (n = 34), A. niger (n = 21), A. tamari (n = 15), A. ruber (E. rubrum) (n = 15), A. proliferans (n = 14), and A. luchuensis (n = 14); 25 species were identified from 533 Aspergillus strains. Aspergillus strains were mainly found during the high temperature fermentation period in the later steps of Meju fermentation.

  13. Improving itaconic acid production through genetic engineering of an industrial Aspergillus terreus strain.

    Science.gov (United States)

    Huang, Xuenian; Lu, Xuefeng; Li, Yueming; Li, Xia; Li, Jian-Jun

    2014-08-11

    Itaconic acid, which has been declared to be one of the most promising and flexible building blocks, is currently used as monomer or co-monomer in the polymer industry, and produced commercially by Aspergillus terreus. However, the production level of itaconic acid hasn't been improved in the past 40 years, and mutagenesis is still the main strategy to improve itaconate productivity. The genetic engineering approach hasn't been applied in industrial A. terreus strains to increase itaconic acid production. In this study, the genes closely related to itaconic acid production, including cadA, mfsA, mttA, ATEG_09969, gpdA, ATEG_01954, acoA, mt-pfkA and citA, were identified and overexpressed in an industrial A. terreus strain respectively. Overexpression of the genes cadA (cis-aconitate decarboxylase) and mfsA (Major Facilitator Superfamily Transporter) enhanced the itaconate production level by 9.4% and 5.1% in shake flasks respectively. Overexpression of other genes showed varied effects on itaconate production. The titers of other organic acids were affected by the introduced genes to different extent. Itaconic acid production could be improved through genetic engineering of the industrially used A. terreus strain. We have identified some important genes such as cadA and mfsA, whose overexpression led to the increased itaconate productivity, and successfully developed a strategy to establish a highly efficient microbial cell factory for itaconate protuction. Our results will provide a guide for further enhancement of the itaconic acid production level through genetic engineering in future.

  14. Heterologous expression of Gaeumannomyces graminis lipoxygenase in Aspergillus nidulans.

    Science.gov (United States)

    Heshof, Ruud; van Schayck, J Paul; Tamayo-Ramos, Juan Antonio; de Graaff, Leo H

    2014-01-01

    Aspergillus sp. contain ppo genes coding for Ppo enzymes that produce oxylipins from polyunsaturated fatty acids. These oxylipins function as signal molecules in sporulation and influence the asexual to sexual ratio of Aspergillus sp. Fungi like Aspergillus nidulans and Aspergillus niger contain just ppo genes where the human pathogenic Aspergillus flavus and Aspergillus fumigatus contain ppo genes as well as lipoxygenases. Lipoxygenases catalyze the synthesis of oxylipins and are hypothesized to be involved in quorum-sensing abilities and invading plant tissue. In this study we used A. nidulans WG505 as an expression host to heterologously express Gaeumannomyces graminis lipoxygenase. The presence of the recombinant LOX induced phenotypic changes in A. nidulans transformants. Also, a proteomic analysis of an A. nidulans LOX producing strain indicated that the heterologous protein was degraded before its glycosylation in the secretory pathway. We observed that the presence of LOX induced the specific production of aminopeptidase Y that possibly degrades the G. graminis lipoxygenase intercellularly. Also the presence of the protein thioredoxin reductase suggests that the G. graminis lipoxygenase is actively repressed in A. nidulans.

  15. Production of xylanases by an Aspergillus niger strain in wastes grain

    Directory of Open Access Journals (Sweden)

    Simone Cristine Izidoro

    2014-08-01

    Full Text Available Many fungi are used in order to extract products from their metabolism through bioprocesses capable of minimizing adverse effects caused by agro-industrial wastes in the environment. The aim of this study was to evaluate the xylanase production by an Aspergillus niger strain, using agro-industrial wastes as substrate. Brewer’s spent grain was the best inducer of xylanase activity. Higher levels of xylanase were obtained when the fungus was grown in liquid Vogel medium, pH 5.0, at 30ºC, during 5 days. The temperature for optimum activity was 50ºC and optimum pH 5.0. The enzyme was stable at 50ºC, with a half-life of 240 min. High pH stability was verified from pH 4.5 to 7.0. These characteristics exhibited by A. niger xylanase turn this enzyme attractive for some industrial applications, such as in feed and food industries. Additionally, the use of brewer’s spent grain, an abundantly available and low-cost residue, as substrate for xylanase production can not only add value and decrease the amount of this waste, but also reduce xylanase production cost.

  16. Biomarkers of Aspergillus spores: Strain typing and protein identification

    Czech Academy of Sciences Publication Activity Database

    Šulc, Miroslav; Pešlová, Kateřina; Žabka, Martin; Hajdúch, M.; Havlíček, Vladimír

    2009-01-01

    Roč. 280, 1-3 (2009), s. 162-168 ISSN 1387-3806 R&D Projects: GA MŠk LC07017; GA ČR GP203/05/P575 Institutional research plan: CEZ:AV0Z50200510 Keywords : aspergillus * spore * protein Subject RIV: EE - Microbiology, Virology Impact factor: 2.117, year: 2009

  17. Toxigenic potentiality of Aspergillus flavus and Aspergillus parasiticus strains isolated from black pepper assessed by an LC-MS/MS based multi-mycotoxin method.

    Science.gov (United States)

    Yogendrarajah, Pratheeba; Devlieghere, Frank; Njumbe Ediage, Emmanuel; Jacxsens, Liesbeth; De Meulenaer, Bruno; De Saeger, Sarah

    2015-12-01

    A liquid chromatography triple quadrupole tandem mass spectrometry method was developed and validated to determine mycotoxins, produced by fungal isolates grown on malt extract agar (MEA). All twenty metabolites produced by different fungal species were extracted using acetonitrile/1% formic acid. The developed method was applied to assess the toxigenic potentiality of Aspergillus flavus (n = 11) and Aspergillus parasiticus (n = 6) strains isolated from black peppers (Piper nigrum L.) following their growth at 22, 30 and 37 °C. Highest mean radial colony growth rates were observed at 30 °C for A. flavus (5.21 ± 0.68 mm/day) and A. parasiticus (4.97 ± 0.33 mm/day). All of the A. flavus isolates produced aflatoxin B1 and O-methyl sterigmatocystin (OMST) while 91% produced aflatoxin B2 (AFB2) and 82% of them produced sterigmatocystin (STERIG) at 30 °C. Except one, all the A. parasiticus isolates produced all the four aflatoxins, STERIG and OMST at 30 °C. Remarkably high AFB1 was produced by some A. flavus isolates at 22 °C (max 16-40 mg/kg). Production of mycotoxins followed a different trend than that of growth rate of both species. Notable correlations were found between different secondary metabolites of both species; R(2) 0.87 between AFB1 and AFB2 production. Occurrence of OMST could be used as a predictor for AFB1 production. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Influence of gamma irradiation on natural mycoflora of poultry feed and effect on morphology, physiology and genetic of strains Aspergillus spp;Influencia da radiacao gama sobre a micobiota natural de racao avicola e seu efeito sobre a morfologia, fisiologia e genetica de cepas de referencia de Aspergillus spp.

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Jessika Mara Martins

    2008-07-01

    Maize flour samples, soy crumb and feed were collected directly from the production line of a poultry farm in Avelar, RJ, and exposed to doses of 0,3.5, 0,8 and 15 kGy of gamma irradiation. Counting, isolation and identification of the contaminant mycoflora were performed before and after irradiation. The radiosensitivity of strains of reference of Aspergillus spp. was determined in CYA medium and in corn for doses ranging from 0 to 8 kGy. Comparison between the morphologies of control and irradiated strains were performed by using macroscopy, optical microscopy and transmission electron microscopy. Toxigenic profile determination and genetic evaluation by RAPD were also carried out. Higher doses have been found to reduce the number of active colonies, causing elimination of the mycoflora at 8 kGy. A larger radiosensitivity of yeasts was observed in comparison with filamentous fungi. A significant reduction in fungi population occurred at 3.5 kGy to levels below the limit that ensures the hygienic quality of ingredients and poultry feeds. The residual mycoflora was found to decrease with post-irradiation time and included mostly Cladosporium spp., Curvularia spp., Fusarium spp. and Aspergillus spp. and sterility of mycelium prevented further identification of the surviving species of Aspergillus spp. Differences in radioresistance were found among species of Aspergillus and the highest tolerance to radiation was observed for A. parasiticus. Initial morphologic changes were found to be more severe during the first isolation after irradiation than in later ones, with the fungi gradually recovering their normal growth rate. Ultrastructural changes in the irradiated strains were observed mostly in the plasmatic membrane and membranous organelles of nuclei and mitochondria. An increase in the rate of production of toxins by the irradiated strains has been found, however no significant alterations have been observed in their genotypes. Such findings apparently indicate

  19. Geographically predominant genotypes of Aspergillus terreus species complex in Austria: s microsatellite typing study

    NARCIS (Netherlands)

    Lackner, M.; Coassin, S.; Haun, M.; Binder, U.; Kronenberg, F.; Haas, H. de; Jank, M.; Maurer, E.; Meis, J.F.; Hagen, F.; Lass-Florl, C.

    2016-01-01

    Aspergillus terreus species complex is recognized as a frequent agent of invasive aspergillosis in Tyrol. The reason for this specific epidemiological situation is unclear. Aspergillus terreus strains isolated from environmental and clinical sources were genotyped using a novel panel of short tandem

  20. Antibiotic effective against Saccharomyces produced by Aspergillus oryzae

    Energy Technology Data Exchange (ETDEWEB)

    Nakata, H.; Sakai, T.; Takeda, M.; Tsukahara, T.

    1980-01-01

    Production of an antibiotic effective against Saccharomyces cerevisiae was investigated in 85 strains of Aspergillus oryzae, isolated from commercial koji molds. The antibiotic was produced by 50 strains. A. oryzae was cultivated at 30 degrees for 15-20 days in koji extract. The crude preparation was obtained by precipitation from the culture filtrate with EtOH, MeOH, or Me/sub 2/CO.

  1. Discrimination of Aspergillus lentulus from Aspergillus fumigatus by Raman spectroscopy and MALDI-TOF MS.

    Science.gov (United States)

    Verwer, P E B; van Leeuwen, W B; Girard, V; Monnin, V; van Belkum, A; Staab, J F; Verbrugh, H A; Bakker-Woudenberg, I A J M; van de Sande, W W J

    2014-02-01

    In 2005, a new sibling species of Aspergillus fumigatus was discovered: Aspergillus lentulus. Both species can cause invasive fungal disease in immune-compromised patients. The species are morphologically very similar. Current techniques for identification are PCR-based or morphology-based. These techniques are labour-intense and not sufficiently discriminatory. Since A. lentulus is less susceptible to several antifungal agents, it is important to correctly identify the causative infectious agent in order to optimize antifungal therapy. In this study we determined whether Raman spectroscopy and/or MALDI-TOF MS were able to differentiate between A. lentulus and A. fumigatus. For 16 isolates of A. lentulus and 16 isolates of A. fumigatus, Raman spectra and peptide profiles were obtained using the Spectracell and MALDI-TOF MS (VITEK MS RUO, bioMérieux) respectively. In order to obtain reliable Raman spectra for A. fumigatus and A. lentulus, the culture medium needed to be adjusted to obtain colourless conidia. Only Raman spectra obtained from colourless conidia were reproducible and correctly identified 25 out of 32 (78 %) of the Aspergillus strains. For VITEK MS RUO, no medium adjustments were necessary. Pigmented conidia resulted in reproducible peptide profiles as well in this case. VITEK MS RUO correctly identified 100 % of the Aspergillus isolates, within a timeframe of approximately 54 h including culture. Of the two techniques studied here, VITEK MS RUO was superior to Raman spectroscopy in the discrimination of A. lentulus from A. fumigatus. VITEK MS RUO seems to be a successful technique in the daily identification of Aspergillus spp. within a limited timeframe.

  2. The Cell Factory Aspergillus Enters the Big Data Era: Opportunities and Challenges for Optimising Product Formation.

    Science.gov (United States)

    Meyer, Vera; Fiedler, Markus; Nitsche, Benjamin; King, Rudibert

    2015-01-01

    Living with limits. Getting more from less. Producing commodities and high-value products from renewable resources including waste. What is the driving force and quintessence of bioeconomy outlines the lifestyle and product portfolio of Aspergillus, a saprophytic genus, to which some of the top-performing microbial cell factories belong: Aspergillus niger, Aspergillus oryzae and Aspergillus terreus. What makes them so interesting for exploitation in biotechnology and how can they help us to address key challenges of the twenty-first century? How can these strains become trimmed for better growth on second-generation feedstocks and how can we enlarge their product portfolio by genetic and metabolic engineering to get more from less? On the other hand, what makes it so challenging to deduce biological meaning from the wealth of Aspergillus -omics data? And which hurdles hinder us to model and engineer industrial strains for higher productivity and better rheological performance under industrial cultivation conditions? In this review, we will address these issues by highlighting most recent findings from the Aspergillus research with a focus on fungal growth, physiology, morphology and product formation. Indeed, the last years brought us many surprising insights into model and industrial strains. They clearly told us that similar is not the same: there are different ways to make a hypha, there are more protein secretion routes than anticipated and there are different molecular and physical mechanisms which control polar growth and the development of hyphal networks. We will discuss new conceptual frameworks derived from these insights and the future scientific advances necessary to create value from Aspergillus Big Data.

  3. Bioleaching of gold, copper and nickel from waste cellular phone PCBs and computer goldfinger motherboards by two Aspergillus nigerstrains

    Directory of Open Access Journals (Sweden)

    Jorge Enrique Madrigal-Arias

    2015-09-01

    Full Text Available In an effort to develop alternate techniques to recover metals from waste electrical and electronic equipment (WEEE, this research evaluated the bioleaching efficiency of gold (Au, copper (Cu and nickel (Ni by two strains of Aspergillus niger in the presence of gold-plated finger integrated circuits found in computer motherboards (GFICMs and cellular phone printed circuit boards (PCBs. These three metals were analyzed for their commercial value and their diverse applications in the industry. Au-bioleaching ranged from 42 to 1% for Aspergillus niger strain MXPE6; with the combination of Aspergillus niger MXPE6 + Aspergillus niger MX7, the Au-bioleaching was 87 and 28% for PCBs and GFICMs, respectively. In contrast, the bioleaching of Cu by Aspergillus niger MXPE6 was 24 and 5%; using the combination of both strains, the values were 0.2 and 29% for PCBs and GFICMs, respectively. Fungal Ni-leaching was only found for PCBs, but with no significant differences among treatments. Improvement of the metal recovery efficiency by means of fungal metabolism is also discussed.

  4. Bioleaching of gold, copper and nickel from waste cellular phone PCBs and computer goldfinger motherboards by two Aspergillus nigerstrains.

    Science.gov (United States)

    Madrigal-Arias, Jorge Enrique; Argumedo-Delira, Rosalba; Alarcón, Alejandro; Mendoza-López, Ma Remedios; García-Barradas, Oscar; Cruz-Sánchez, Jesús Samuel; Ferrera-Cerrato, Ronald; Jiménez-Fernández, Maribel

    2015-01-01

    In an effort to develop alternate techniques to recover metals from waste electrical and electronic equipment (WEEE), this research evaluated the bioleaching efficiency of gold (Au), copper (Cu) and nickel (Ni) by two strains of Aspergillus niger in the presence of gold-plated finger integrated circuits found in computer motherboards (GFICMs) and cellular phone printed circuit boards (PCBs). These three metals were analyzed for their commercial value and their diverse applications in the industry. Au-bioleaching ranged from 42 to 1% for Aspergillus niger strain MXPE6; with the combination of Aspergillus niger MXPE6 + Aspergillus niger MX7, the Au-bioleaching was 87 and 28% for PCBs and GFICMs, respectively. In contrast, the bioleaching of Cu by Aspergillus niger MXPE6 was 24 and 5%; using the combination of both strains, the values were 0.2 and 29% for PCBs and GFICMs, respectively. Fungal Ni-leaching was only found for PCBs, but with no significant differences among treatments. Improvement of the metal recovery efficiency by means of fungal metabolism is also discussed.

  5. Identification and analysis of Ku70 and Ku80 homologs in the koji molds Aspergillus sojae and Aspergillus oryzae.

    Science.gov (United States)

    Takahashi, Tadashi; Masuda, Tsutomu; Koyama, Yasuji

    2006-01-01

    Ku genes play a key role in the non-homologous end-joining pathway. We have identified Ku70 and Ku80 homologs in the koji molds Aspergillus sojae and Aspergillus oryzae, and have constructed the disruption mutants of Ku70, Ku80, and Ku70-80 to characterize the phenotypic change in these mutants. Neither Ku70- nor Ku80-disrupted strains show hypersensitivity to the DNA damaging agents methylmethane sulfonate (MMS) and phleomycin. Moreover, undesirable phenotypes, such as poor growth or repressed conidiospore formation, were not observed in the Ku-disrupted A. sojae and A. oryzae.

  6. Glucoamylase production by a newly isolated strain of Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Sinkar, V.P.; Lewis, N.F.

    1982-01-01

    Glucoamylase production by Aspergillus niger 57 was studied in complex and synthetic media under stationary vs. submerged conditions. Stationary cultivation resulted in significantly greater yields than did submerged culture. Crude enzyme activity was optimum at 60 degrees and pH 4.0.

  7. Comparison of species composition and fumonisin production in Aspergillus section Nigri populations in maize kernels from USA and Italy.

    Science.gov (United States)

    Susca, Antonia; Moretti, Antonio; Stea, Gaetano; Villani, Alessandra; Haidukowski, Miriam; Logrieco, Antonio; Munkvold, Gary

    2014-10-01

    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 key component in developing effective management strategies. Although some fungi in Aspergillus sect. Nigri are known to produce fumonisins, little is known about the species which are common in maize and whether they make a measurable contribution to fumonisin contamination of maize grain. In this work, we evaluated populations of Aspergillus sect. Nigri isolated from maize in USA and Italy, focusing on analysis of housekeeping genes, the fum8 gene and in vitro capability of producing fumonisins. DNA sequencing was used to identify Aspergillus strains belonging to sect. Nigri, in order to compare species composition between the two populations, which might influence specific mycotoxicological risks. Combined beta-tubulin/calmodulin sequences were used to genetically characterize 300 strains (199 from Italy and 101 from USA) which grouped into 4 clades: Aspergillus welwitschiae (syn. Aspergillus awamori, 14.7%), Aspergillus tubingensis (37.0%) and Aspergillus niger group 1 (6.7%) and group 2 (41.3%). Only one strain was identified as Aspergillus carbonarius. Species composition differed between the two populations; A. niger predominated among the USA isolates (69%), but comprised a smaller percentage (38%) of Italian isolates. Conversely, A. tubingensis and A. welwitschiae occurred at higher frequencies in the Italian population (42% and 20%, respectively) than in the USA population (27% and 5%). The evaluation of FB2 production on CY20S agar revealed 118 FB2 producing and 84

  8. Keratitis caused by the recently described new species Aspergillus brasiliensis: two case reports

    Directory of Open Access Journals (Sweden)

    Vágvölgyi Csaba

    2010-02-01

    Full Text Available Abstract Introduction Human infections caused by Aspergillus brasiliensis have not yet been reported. We describe the first two known cases of fungal keratitis caused by Aspergillus brasiliensis. Case presentations A 49-year-old Indian Tamil woman agricultural worker came with pain and defective vision in the right eye for one month. Meanwhile, a 35-year-old Indian Tamil woman presented with a history of a corneal ulcer involving the left eye for 15 days. The fungal strains isolated from these two cases were originally suspected to belong to Aspergillus section Nigri based on macro- and micromorphological characteristics. Molecular identification revealed that both isolates represent A. brasiliensis. Conclusion The two A. brasiliensis strains examined in this study were part of six keratitis isolates from Aspergillus section Nigri, suggesting that this recently described species may be responsible for a significant proportion of corneal infections caused by black Aspergilli. The presented cases also indicate that significant differences may occur between the severities of keratitis caused by individual isolates of A. brasiliensis.

  9. Effect of irradiation on protease production by a Philippine strain of Aspergillus oryzae (ahlburg) cohn

    International Nuclear Information System (INIS)

    Anglo, P.G.

    1974-03-01

    The Philippine strain of Aspergillus oryzae (ahlburg) cohn. was exposed to ultraviolet rays and ionizing radiation from cobalt-60 for the purpose of obtaining possible mutants or resistant strains which produce powerful proteolytic enzymes. Out of 58 isolates, only 3 gave significant proteolytic values (PV) high enough to merit further investigation. The isolates, G-10, G-110, and 23-110, were picked from plates exposed to gamma rays from cobalt-60. Optimum incubation temperature for these isolates for highest percentage of active protease was 24 0 -27 0 C. The isolates were found capable of producing active protease from the second day of incubation up to the fifth day, whereas the activity of the parent strain was retained the fourth day only. The isolates showed maximum digestive ability at 25 0 -55 0 C, giving proteolytic values of 833. The pH activity curves showed that the enzyme produced by the irradiated isolates G-10 and G-110 were very active at pH 9.0-10.0, and isolate 23-110 at pH 6.0-10.0. The parent strain revealed two pH optima, one at pH 7.5-8.5 and the other at pH 9.0-9.5. Crude enzyme powder gave activities comparable to alkalase and maxatase, commercial proteolytic enzymes imported from Belgium and Netherlands being used as component of laundry detergents by some manufacturing companies in the Philippines. The results obtained give valuable information for the commercial application of the enzyme. Since the organism can produce high yields of protease from copra meal, a by-product of the coconut industry, commerical feasibility may be envisioned in the near future

  10. [Aspergillus species in hospital environments with pediatric patients in critical condition].

    Science.gov (United States)

    Fernández, Mariana; Cattana, María; Rojas, Florencia; Sosa, María de Los Ángeles; Aguirre, Clarisa; Vergara, Marta; Giusiano, Gustavo

    2014-01-01

    Aspergillus is a group of opportunistic fungi that cause infections, with high morbimortality in immunosuppressed patients. Aspergillus fumigatus is the most frequent species in these infections, although the incidence of other species has increased in the last few years. To evaluate the air fungal load and the diversity of Aspergillus species in hospitals with pediatric patients in critical condition. The Intensive Care Unit and Burns Unit of a pediatric hospital were sampled every 15 days during the autumn and spring seasons. The air samples were collected with SAS Super 100(®) and the surface samples were collected by swab method. The UFC/m(3) counts found exceeded the acceptable levels. The UFC/m(3) and the diversity of Aspergillus species found in the Intensive Care Unit were higher than those found in the Burns Unit. The fungal load and the diversity of species within the units were higher than those in control environments. The use of both methods -SAS and swab- allowed the detection of a higher diversity of species, with 96 strains of Aspergillus being isolated and 12 species identified. The outstanding findings were Aspergillus sydowii, Aspergillus niger, Aspergillus flavus, Aspergillus terreus and Aspergillus parasiticus, due to their high frequency. Aspergillus fumigatus, considered unacceptable in indoor environments, was isolated in both units. Aspergillus was present with high frequency in these units. Several species are of interest in public health for being potential pathogenic agents. Air control and monitoring are essential in the prevention of these infections. Copyright © 2013 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.

  11. Constitutive expression of fluorescent protein by Aspergillus var. niger and Aspergillus carbonarius to monitor fungal colonization in maize plants.

    Science.gov (United States)

    Palencia, Edwin Rene; Glenn, Anthony Elbie; Hinton, Dorothy Mae; Bacon, Charles Wilson

    2013-09-01

    Aspergillus niger and Aspergillus carbonarius are two species in the Aspergillus section Nigri (black-spored aspergilli) frequently associated with peanut (Arachis hypogea), maize (Zea mays), and other plants as pathogens. These infections are symptomless and as such are major concerns since some black aspergilli produce important mycotoxins, ochratoxins A, and the fumonisins. To facilitate the study of the black aspergilli-maize interactions with maize during the early stages of infections, we developed a method that used the enhanced yellow fluorescent protein (eYFP) and the monomeric red fluorescent protein (mRFP1) to transform A. niger and A. carbonarius, respectively. The results were constitutive expressions of the fluorescent genes that were stable in the cytoplasms of hyphae and conidia under natural environmental conditions. The hyphal in planta distribution in 21-day-old seedlings of maize were similar wild type and transformants of A. niger and A. carbonarius. The in planta studies indicated that both wild type and transformants internally colonized leaf, stem and root tissues of maize seedlings, without any visible disease symptoms. Yellow and red fluorescent strains were capable of invading epidermal cells of maize roots intercellularly within the first 3 days after inoculation, but intracellular hyphal growth was more evident after 7 days of inoculation. We also tested the capacity of fluorescent transformants to produce ochratoxin A and the results with A. carbonarius showed that this transgenic strain produced similar concentrations of this secondary metabolite. This is the first report on the in planta expression of fluorescent proteins that should be useful to study the internal plant colonization patterns of two ochratoxigenic species in the Aspergillus section Nigri. © 2013.

  12. Effects of microwaves on the reduction of Aspergillus flavus and Aspergillus parasiticus on brown rice (Oryza sativa L.) and barley (Hordeum vulgare L.).

    Science.gov (United States)

    Lee, Seung-Hun; Park, Shin Young; Byun, Kye-Hwan; Chun, Hyang Sook; Ha, Sang-Do

    2017-07-01

    Aspergillus flavus and Aspergillus parasiticus are primary pathogen moulds on brown rice and barley. This study investigated the effects of microwave irradiation (MWI) (2450 MHz, 700 W, 10-50 s) on inactivation of A. flavus and A. parasiticus on brown rice and barley and the quality of these samples. The counts of both strains were significantly (p  90% reduction of mould without causing deleterious changes to the colour, moisture content and sensory qualities of these cereals.

  13. Mutagenic strain improvement of aspergillus niger (MBL-1511) and optimization of cultural conditions for boosted lipolytic potential through submerged fermentation

    International Nuclear Information System (INIS)

    Sidra, A.; Aftikhar, T.

    2016-01-01

    In present study an isolated hyper producer of Aspergillus niger (MBL-1511) was treated for sodium azide mutagenesis. Results showed 147.27 % enhanced extracellular lipase activity after 150 minutes of sodium azide treatment. Wild and mutant hyper lipase producer strains were exploited to submerged fermentation (SmF). Brassica meal as an additive agro waste product to the basal medium was optimized. Experimental conditions optima were 10% inoculum size, 30 degree C temperature, 96 h rate of fermentation and pH 6 for maximum lipases production. Molasses and Ammonium nitrate were optimized as the best carbon and nitrogen sources (0.6% and 0.4%) w/v respectively and sunflower oil 1% (v/v) as better inducer. Finally, an effective mutant (MBL-1511SA-4(150 min)) having of 176.10% enhanced extracellular lipases production over wild (MBL-1511) strain was acquired. (author)

  14. Improvement of raw starch digestibility by ion-beam mutation of Aspergillus awamori

    Energy Technology Data Exchange (ETDEWEB)

    Amsal, Aryanti [National Atomic Energy Agency, Jakarta (Indonesia); Takigami, Machiko; Ito, Hitoshi

    1998-09-01

    Aspergillus awamori possess the ability to express raw starch digestibility. For the effective utilization of starchy crops produced in South-Asian countries, it is important to achieve the digestion of raw starchs for industrial fermentation process. In this study, higher ratio of mutant strains of Aspergillus awamori IFO4033 were isolated by irradiation of C{sup 5+} ion-beam on freeze dried spores with improvement of enzyme production for two-to threefold in the extracellular {alpha}-amylase compared with gamma-irradiation. The digestibility of raw starch from cassava, sago and sukun increased remarkably about two-to threefold by some mutant strains obtained from irradiation of C{sup 5+} ion-beam. (author)

  15. Improvement of raw starch digestibility by ion-beam mutation of Aspergillus awamori

    International Nuclear Information System (INIS)

    Amsal, Aryanti; Takigami, Machiko; Ito, Hitoshi

    1998-01-01

    Aspergillus awamori possess the ability to express raw starch digestibility. For the effective utilization of starchy crops produced in South-Asian countries, it is important to achieve the digestion of raw starchs for industrial fermentation process. In this study, higher ratio of mutant strains of Aspergillus awamori IFO4033 were isolated by irradiation of C 5+ ion-beam on freeze dried spores with improvement of enzyme production for two-to threefold in the extracellular α-amylase compared with gamma-irradiation. The digestibility of raw starch from cassava, sago and sukun increased remarkably about two-to threefold by some mutant strains obtained from irradiation of C 5+ ion-beam. (author)

  16. Genetic and phenotypic diversity of naturally isolated wild strains of Aspergillus niger with hyper glucose oxidase production

    Directory of Open Access Journals (Sweden)

    MAHMOUD EL-HARIRI

    2015-12-01

    Full Text Available Glucose oxidase (GOx is the basic stone for many of biological industry worldwide. The improvement of GOx production basically depends on selection of hyper producer strain of Aspergillus niger. Selective isolation and screening for natural hyper producer strains of A. niger and sequence analysis of the GOD gene, which is responsible for production of the enzyme, are very effective approaches to investigate the naturally modified strains of A. niger with hyper productive capacity of GOx enzyme. The aims of the current study were selective isolation of naturally hyper GOx producing strains of A. niger and evaluation of their GOx activities under optimized parameters in the laboratory. Five wild Egyptian isolates of A. niger were screened for GOx and catalase activity using two types of modified basal liquid media. The GOx activity was evaluated by high throughout liquid phase system. The isolates showed a variable activity for GOx production ranged from 0 to 28.7 U.ml-1. One isolate coded Strain 7 was negative GOx producer on Vogel's broth medium in comparison to other isolates, while its GOx activity on Cazpek Dox was considered as positive (7.28 U.ml-1. It was concluded that GOx production is affected by three controllable factors – the basal media components, time of incubation, and the strain with its adaption to the media components‎. Also, the catalase activity was tested and it was produced with a different degree of variability, which may be reflected on GOx stability. GOD genes of these wild variant of A. niger were cloned and sequenced to determine intraspecies diversity of GOD between the wild variants. The comparison of isolated wild variants to other reference hyper GOx producer strains of A. niger was performed to determine if the GOD sequence analysis of these strains can be distinguished based on their GOx activity. This is the first report for isolation and detection of naturally A. niger hyper GOx-producer strains with

  17. Chemometric Analysis of the Volatile Compounds Generated by Aspergillus carbonarius Strains Isolated from Grapes and Dried Vine Fruits

    Directory of Open Access Journals (Sweden)

    Zhan Cheng

    2018-02-01

    Full Text Available Ochratoxin A (OTA contamination in grape production is an important problem worldwide. Microbial volatile organic compounds (MVOCs have been demonstrated as useful tools to identify different toxigenic strains. In this study, Aspergillus carbonarius strains were classified into two groups, moderate toxigenic strains (MT and high toxigenic strains (HT, according to OTA-forming ability. The MVOCs were analyzed by GC-MS and the data processing was based on untargeted profiling using XCMS Online software. Orthogonal projection to latent structures discriminant analysis (OPLS-DA was performed using extract ion chromatogram GC-MS datasets. For contrast, quantitative analysis was also performed. Results demonstrated that the performance of the OPLS-DA model of untargeted profiling was better than the quantitative method. Potential markers were successfully discovered by variable importance on projection (VIP and t-test. (E-2-octen-1-ol, octanal, 1-octen-3-one, styrene, limonene, methyl-2-phenylacetate and 3 unknown compounds were selected as potential markers for the MT group. Cuparene, (Z-thujopsene, methyl octanoate and 1 unknown compound were identified as potential markers for the HT groups. Finally, the selected markers were used to construct a supported vector machine classification (SVM-C model to check classification ability. The models showed good performance with the accuracy of cross-validation and test prediction of 87.93% and 92.00%, respectively.

  18. Biodiversity of mycobiota throughout the Brazil nut supply chain: From rainforest to consumer.

    Science.gov (United States)

    Taniwaki, Marta H; Frisvad, Jens C; Ferranti, Larissa S; de Souza Lopes, Aline; Larsen, Thomas O; Fungaro, Maria Helena P; Iamanaka, Beatriz T

    2017-02-01

    A total of 172 Brazil nut samples (114 in shell and 58 shelled) from the Amazon rainforest region and São Paulo state, Brazil was collected at different stages of the Brazil nut production chain: rainforest, street markets, processing plants and supermarkets. The mycobiota of the Brazil nut samples were evaluated and also compared in relation to water activity. A huge diversity of Aspergillus and Penicillium species were found, besides Eurotium spp., Zygomycetes and dematiaceous fungi. A polyphasic approach using morphological and physiological characteristics, as well as molecular and extrolite profiles, were studied to distinguish species among the more important toxigenic ones in Aspergillus section Flavi and A. section Nigri. Several metabolites and toxins were found in these two sections. Ochratoxin A (OTA) was found in 3% of A. niger and 100% of A. carbonarius. Production of aflatoxins B and G were found in all isolates of A. arachidicola, A. bombycis, A. nomius, A. pseudocaelatus and A. pseudonomius, while aflatoxin B was found in 38% of A. flavus and all isolates of A. pseudotamarii. Cyclopiazonic acid (CPA) was found in A. bertholletius (94%), A. tamarii (100%), A. caelatus (54%) and A. flavus (41%). Tenuazonic acid, a toxin commonly found in Alternaria species was produced by A. bertholletius (47%), A. caelatus (77%), A. nomius (55%), A. pseudonomius (75%), A. arachidicola (50%) and A. bombycis (100%). This work shows the changes of Brazil nut mycobiota and the potential of mycotoxin production from rainforest to consumer, considering the different environments which exist until the nuts are consumed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. An evaluation of aflatoxin and cyclopiazonic acid production in Aspergillus oryzae.

    Science.gov (United States)

    Kim, Nam Yeun; Lee, Jin Hee; Lee, Inhyung; Ji, Geun Eog

    2014-06-01

    To date, edible fungi such as Aspergillus flavus var. oryzae (A. oryzae) has been considered as safe. However, some strains can produce mycotoxins. Thus, the biosynthetic ability to produce mycotoxins should be reevaluated to determine the safety of edible fungi. We analyzed the production of aflatoxins and cyclopiazonic acid (CPA) from edible fungi such as A. oryzae isolated from various Korean foods using multiplex PCR, enzyme-linked immunosorbent assay, and high-performance liquid chromatography (HPLC). In the multiplex PCR analysis of aflatoxin biosynthetic genes omtB, aflR, ver-1, and omtA, 5 of 19 Aspergillus strains produced all PCR products. Among them, aflatoxin B1 and aflatoxin B2 were detected from only A. flavus KACC 41403 by HPLC. Aflatoxins were not detected from the other four strains that produced all positive PCR bands. Aflatoxin also was not detected from 12 strains that had PCR patterns without aflR or ver-1 and from 2 strains that did not produce any of the expected PCR products. Only the seven A. oryzae strains that produced all of the positive PCR bands including the CPA biosynthetic genes maoA, dmaT, and pks-nrps produced CPA. CPA and aflatoxin production must be evaluated before A. oryzae strains are used for the development of fermented foods.

  20. A nonribosomal peptide synthetase (Pes1) confers protection against oxidative stress in Aspergillus fumigatus.

    Science.gov (United States)

    Reeves, Emer P; Reiber, Kathrin; Neville, Claire; Scheibner, Olaf; Kavanagh, Kevin; Doyle, Sean

    2006-07-01

    Aspergillus fumigatus is an important human fungal pathogen. The Aspergillus fumigatus genome contains 14 nonribosomal peptide synthetase genes, potentially responsible for generating metabolites that contribute to organismal virulence. Differential expression of the nonribosomal peptide synthetase gene, pes1, in four strains of Aspergillus fumigatus was observed. The pattern of pes1 expression differed from that of a putative siderophore synthetase gene, sidD, and so is unlikely to be involved in iron acquisition. The Pes1 protein (expected molecular mass 698 kDa) was partially purified and identified by immunoreactivity, peptide mass fingerprinting (36% sequence coverage) and MALDI LIFT-TOF/TOF MS (four internal peptides sequenced). A pes1 disruption mutant (delta pes1) of Aspergillus fumigatus strain 293.1 was generated and confirmed by Southern and western analysis, in addition to RT-PCR. The delta pes1 mutant also showed significantly reduced virulence in the Galleria mellonella model system (P < 0.001) and increased sensitivity to oxidative stress (P = 0.002) in culture and during neutrophil-mediated phagocytosis. In addition, the mutant exhibited altered conidial surface morphology and hydrophilicity, compared to Aspergillus fumigatus 293.1. It is concluded that pes1 contributes to improved fungal tolerance against oxidative stress, mediated by the conidial phenotype, during the infection process.

  1. Expression of human lymphotoxin alpha in Aspergillus niger

    NARCIS (Netherlands)

    Krasevec, N.; Hondel, C.A.M.J.J. van de; Komel, R.

    2000-01-01

    A gene-fusion expression strategy was applied for heterologous expression of human lymphotoxin alpha (LTα) in the Aspergillus niger AB1.13 protease-deficient strain. The LTα gene was fused with the A. niger glucoamylase GII-form as a carrier-gene, behind its transcription control and secretion

  2. Occurrence and biodiversity of Aspergillus section Nigri on 'Tannat' grapes in Uruguay.

    Science.gov (United States)

    Garmendia, Gabriela; Vero, Silvana

    2016-01-04

    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 producing species was not detected. OTA production in culture medium was evaluated for native isolates from A. niger aggregate and compared to levels produced by a type strain of A. carbonarius. This work also includes the development of quick and easy molecular methods to identify black aspergilli to species level, avoiding sequencing. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Aspergillus nidulans cell wall composition and function change in response to hosting several Aspergillus fumigatus UDP-galactopyranose mutase activity mutants.

    Directory of Open Access Journals (Sweden)

    Md Kausar Alam

    Full Text Available Deletion or repression of Aspergillus nidulans ugmA (AnugmA, involved in galactofuranose biosynthesis, impairs growth and increases sensitivity to Caspofungin, a β-1,3-glucan synthesis antagonist. The A. fumigatus UgmA (AfUgmA crystal structure has been determined. From that study, AfUgmA mutants with altered enzyme activity were transformed into AnugmA▵ to assess their effect on growth and wall composition in A. nidulans. The complemented (AnugmA::wild type AfugmA strain had wild type phenotype, indicating these genes had functional homology. Consistent with in vitro studies, AfUgmA residues R182 and R327 were important for its function in vivo, with even conservative amino (RK substitutions producing AnugmA? phenotype strains. Similarly, the conserved AfUgmA loop III histidine (H63 was important for Galf generation: the H63N strain had a partially rescued phenotype compared to AnugmA▵. Collectively, A. nidulans strains that hosted mutated AfUgmA constructs with low enzyme activity showed increased hyphal surface adhesion as assessed by binding fluorescent latex beads. Consistent with previous qPCR results, immunofluorescence and ELISA indicated that AnugmA▵ and AfugmA-mutated A. nidulans strains had increased α-glucan and decreased β-glucan in their cell walls compared to wild type and AfugmA-complemented strains. Like the AnugmA▵ strain, A. nidulans strains containing mutated AfugmA showed increased sensitivity to antifungal drugs, particularly Caspofungin. Reduced β-glucan content was correlated with increased Caspofungin sensitivity. Aspergillus nidulans wall Galf, α-glucan, and β-glucan content was correlated in A. nidulans hyphal walls, suggesting dynamic coordination between cell wall synthesis and cell wall integrity.

  4. Improving cellulase production by Aspergillus niger using adaptive evolution

    NARCIS (Netherlands)

    Patyshakuliyeva, Aleksandrina; Arentshorst, Mark; Allijn, Iris E; Ram, Arthur F J; de Vries, Ronald P; Gelber, Isabelle Benoit

    OBJECTIVES: To evaluate the potential of adaptive evolution as a tool in generating strains with an improved production of plant biomass degrading enzymes. RESULTS: An Aspergillus niger cellulase mutant was obtained by adaptive evolution. Physiological properties of this mutant revealed a five times

  5. PCR-RFLP on β-tubulin gene for rapid identification of the most clinically important species of Aspergillus.

    Science.gov (United States)

    Nasri, Tuba; Hedayati, Mohammad Taghi; Abastabar, Mahdi; Pasqualotto, Alessandro C; Armaki, Mojtaba Taghizadeh; Hoseinnejad, Akbar; Nabili, Mojtaba

    2015-10-01

    Aspergillus species are important agents of life-threatening infections in immunosuppressed patients. Proper speciation in the Aspergilli has been justified based on varied fungal virulence, clinical presentations, and antifungal resistance. Accurate identification of Aspergillus species usually relies on fungal DNA sequencing but this requires expensive equipment that is not available in most clinical laboratories. We developed and validated a discriminative low-cost PCR-based test to discriminate Aspergillus isolates at the species level. The Beta tubulin gene of various reference strains of Aspergillus species was amplified using the universal fungal primers Bt2a and Bt2b. The PCR products were subjected to digestion with a single restriction enzyme AlwI. All Aspergillus isolates were subjected to DNA sequencing for final species characterization. The PCR-RFLP test generated unique patterns for six clinically important Aspergillus species, including Aspergillus flavus, Aspergillus fumigatus, Aspergillus nidulans, Aspergillus terreus, Aspergillus clavatus and Aspergillus nidulans. The one-enzyme PCR-RFLP on Beta tubulin gene designed in this study is a low-cost tool for the reliable and rapid differentiation of the clinically important Aspergillus species. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. The effect of CreA in glucose and xylose catabolism in Aspergillus nidulans

    DEFF Research Database (Denmark)

    Prathumpai, Wai; Mcintyre, Mhairi; Nielsen, Jens

    2004-01-01

    The catabolism of glucose and xylose was studied in a wild type and creA deleted (carbon catabolite de-repressed) strain of Aspergillus nidulans. Both strains were cultivated in bioreactors with either glucose or xylose as the sole carbon source, or in the presence of both sugars. In the cultivat......The catabolism of glucose and xylose was studied in a wild type and creA deleted (carbon catabolite de-repressed) strain of Aspergillus nidulans. Both strains were cultivated in bioreactors with either glucose or xylose as the sole carbon source, or in the presence of both sugars...... on the sugar mixture, glucose repression of xylose utilisation was observed; with xylose utilisation occurring only after glucose was depleted. This phenomenon was not seen in the creA deleted strain, where glucose and xylose were catabolised simultaneously. Measurement of key metabolites and the activities...... of key enzymes in the xylose utilisation pathway revealed that xylose metabolism was occurring in the creA deleted strain, even at high glucose concentrations. Conversely, in the wild type strain, activities of the key enzymes for xylose metabolism increased only when the effects of glucose repression...

  7. Biosynthesis, purification and characterization of endoglucanase from a xylanase producing strain Aspergillus niger B03

    Directory of Open Access Journals (Sweden)

    Georgi Todorov Dobrev

    2012-03-01

    Full Text Available An extracellular endoglucanase was isolated from the culture liquid of xylanase producing strain Aspergillus niger B03. The enzyme was purified to a homogenous form, using consecutive ultrafiltration, anion exchange chromatography, and gel filtration. Endoglucanase was a monomer protein with a molecular weight of 26,900 Da determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and 28,800 Da determined by gel filtration. The optimal pH and temperature values for the enzyme action were 3.5 and 65ºC respectively. Endoglucanase was stable at 40ºC, pH 3.0 for 210 min. The substrate specificity of the enzyme was determined with carboxymethyl cellulose, filter paper, and different glycosides. Endoglucanase displayed maximum activity in the case of carboxymethyl cellulose, with a Km value of 21.01 mg/mL. The substrate specificity and the pattern of substrate degradation suggested that the enzyme is an endoglucanase. Endoglucanase showed a synergism with endoxylanase in corn cobs hydrolysis.

  8. Experimental study of Aspergillus flavus fungus from uranium mines

    Energy Technology Data Exchange (ETDEWEB)

    Kusak, V. (Ceskoslovenska Akademie Ved, Prague. Ustav Experimentalni Mediciny)

    1982-06-01

    Cultivation is discussed of fungus strain Aspergillus flavus obtained from materials from uranium mines. It was found that an addition of 0.6 g of uranium in form of uranyl acetate or of 0.6 g of thorium in form on thorium nitrate in 1000 ml of the standard medium had stimulating effects on the growth and sporulation of Aspergillus flavus. Irradiating the cultivated fungus through a polyethylene foil did not show a stimulating effect. It is stated that uranium and its daughters must be directly present in the culture medium for their stimulating effect on growth and sporulation to manifest itself.

  9. Metabolic engineering of the morphology of Aspergillus oryzae by altering chitin synthesis

    DEFF Research Database (Denmark)

    Muller, C.; Mcintyre, Mhairi; Hansen, Kim

    2002-01-01

    Morphology and alpha-amylase production during submerged cultivation were examined in a wild-type strain (A1560) and in strains of Aspergillus oryzae in which chitin synthase B (chsB) and chitin synthesis myosin A (csmA) have been disrupted (ChsB/G and CM101). In a flowthrough cell, the growth...

  10. Pharmacodynamics of isavuconazole in an Aspergillus fumigatus mouse infection model

    NARCIS (Netherlands)

    Seyedmousavi, S.; Bruggemann, R.J.; Meis, J.F.G.M.; Melchers, W.J.G.; Verweij, P.E.; Mouton, J.W.

    2015-01-01

    Azole resistance is an emerging problem in Aspergillus fumigatus which translates into treatment failure. Alternative treatments with new azoles may improve therapeutic outcome in invasive aspergillosis (IA) even for strains with decreased susceptibility to current azoles. The in vivo efficacy of

  11. Aspergillus: introduction

    Science.gov (United States)

    Species in the genus Aspergillus possess versatile metabolic activities that impact our daily life both positively and negatively. Aspergillus flavus and Aspergillus oryzae are closely related fungi. While the former is able to produce carcinogenic aflatoxins and is an etiological agent of aspergill...

  12. Free chlorine and monochloramine inactivation kinetics of Aspergillus and Penicillium in drinking water.

    Science.gov (United States)

    Ma, Xiao; Bibby, Kyle

    2017-09-01

    Fungi are near-ubiquitous in potable water distribution systems, but the disinfection kinetics of commonly identified fungi are poorly studied. In the present study, laboratory scale experiments were conducted to evaluate the inactivation kinetics of Aspergillus fumigatus, Aspergillus versicolor, and Penicillium purpurogenum by free chlorine and monochloramine. The observed inactivation data were then fit to a delayed Chick-Watson model. Based on the model parameter estimation, the Ct values (integrated product of disinfectant concentration C and contact time t over defined time intervals) for 99.9% inactivation of the tested fungal strains ranged from 48.99 mg min/L to 194.7 mg min/L for free chlorine and from 90.33 mg min/L to 531.3 mg min/L for monochloramine. Fungal isolates from a drinking water system (Aspergillus versicolor and Penicillium purpurogenum) were more disinfection resistant than Aspergillus fumigatus type and clinical isolates. The required 99.9% inactivation Ct values for the tested fungal strains are higher than E. coli, a commonly monitored indicator bacteria, and within a similar range for bacteria commonly identified within water distribution systems, such as Mycobacterium spp. and Legionella spp. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Cremophor EL stimulates mitotic recombination in uvsH//uvsH diploid strain of Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    Cleverson Busso

    2004-03-01

    Full Text Available Cremophor EL is a solubilizer and emulsifier agent used in the pharmaceutical and foodstuff industries. The solvent is the principal constituent of paclitaxel's clinical formulation vehicle. Since mitotic recombination plays a crucial role in multistep carcinogenesis, the study of the recombinagenic potential of chemical compounds is of the utmost importance. In our research genotoxicity of cremophor EL has been studied by using an uvsH//uvsH diploid strain of Aspergillus nidulans. Since it spends a great part of its cell cycle in the G2period, this fungus is a special screening system for the study of mitotic recombination induced by chemical substances. Homozygotization Indexes (HI for paba and bi markers from heterozygous B211//A837 diploid strain were determined for the evaluation of the recombinagenic effect of cremophor EL. It has been shown that cremophor EL induces increase in mitotic crossing-over events at nontoxic concentrations (0.05 and 0.075% v/v.Cremofor EL (CEL é um solubilizante e emulsificante amplamente utilizado nas indústrias farmacêuticas e de gêneros alimentícios. É o principal veículo empregado nas formulações clínicas do antineoplásico paclitaxel. Considerando-se que a recombinação mitótica desempenha importante função no processo de carcinogênese, o estudo de substâncias químicas com potencial recombinagênico assume importância crucial, no sentido de se detectar aquelas que eventualmente possam atuar como promotoras de neoplasias. A genotoxicidade do cremofor EL foi estudada no presente trabalho, utilizando-se uma linhagem diplóide uvsH//uvsH de Aspergillus nidulans. Neste fungo as células vegetativas comumente repousam no período G2 do ciclo celular, facilitando a ocorrência da recombinação mitótica. O efeito recombinagênico do CEL foi avaliado através da determinação dos Índices de Homozigotização para os marcadores nutricionais paba e bi do diplóide heterozigoto B211//A837. Os

  14. The proportion of non-aflatoxigenic strains of the Aspergillus flavus/oryzae complex from meju by analyses of the aflatoxin biosynthetic genes.

    Science.gov (United States)

    Hong, Seung-Beom; Lee, Mina; Kim, Dae-Ho; Chung, Soo-Hyun; Shin, Hyeon-Dong; Samson, Robert A

    2013-12-01

    Strains of the Aspergillus flavus/oryzae complex are frequently isolated from meju, a fermented soybean product, that is used as the starting material for ganjang (soy sauce) and doenjang (soybean paste) production. In this study, we examined the aflatoxin producing capacity of A. flavus/oryzae strains isolated from meju. 192 strains of A. flavus/oryzae were isolated from more than 100 meju samples collected from diverse regions of Korea from 2008 to 2011, and the norB-cypA, omtA, and aflR genes in the aflatoxin biosynthesis gene cluster were analyzed. We found that 178 strains (92.7%) belonged to non-aflatoxigenic group (Type I of norB-cypA, IB-L-B-, IC-AO, or IA-L-B- of omtA, and AO type of aflR), and 14 strains (7.3%) belonged to aflatoxin-producible group (Type II of norB-cypA, IC-L-B+/B- or IC-L-B+ of omtA, and AF type of aflR). Only 7 strains (3.6%) in the aflatoxin-producible group produced aflatoxins on Czapek yeast-extract medium. The aflatoxin-producing capability of A. flavus/oryzae strains from other sources in Korea were also investigated, and 92.9% (52/56) strains from air, 93.9% (31/33) strains from rice straw, 91.7% (11/12) strains from soybean, 81.3% (13/16) strains from corn, 82% (41/50) strains from peanut, and 73.2% (41/56) strains from arable soil were included in the non-aflatoxigenic group. The proportion of non-aflatoxigenicity of meju strains was similar to that of strains from soybean, air and rice straw, all of which have an effect on the fermentation of meju. The data suggest that meju does not have a preference for non-aflatoxigenic or aflatoxin-producible strains of A. flavus/oryzae from the environment of meju. The non-aflatoxigenic meju strains are proposed to be named A. oryzae, while the meju strains that can produce aflatoxins should be referred to A. flavus in this study.

  15. Aspartic protease from Aspergillus (Eurotium) repens strain MK82 is involved in the hydrolysis and decolourisation of dried bonito (Katsuobushi).

    Science.gov (United States)

    Aoki, Kenji; Matsubara, Sayaka; Umeda, Mayo; Tachibanac, Shusaku; Doi, Mikiharu; Takenaka, Shinji

    2013-04-01

    Katsuobushi is a dried, smoked and fermented bonito used in Japanese cuisine. During the fermentation process with several Aspergillus species, the colour of Katsuobushi gradually changes from a dark reddish-brown derived from haem proteins to pale pink. The change in colour gives Katsuobushi a higher ranking and price. This study aimed to elucidate the mechanism of decolourisation of Katsuobushi. A decolourising factor from the culture supernatant of Aspergillus (Eurotium) repens strain MK82 was purified to homogeneity. The purification was monitored by measuring the decolourising activity using equine myoglobin and bovine haemoglobin as substrates. It was found that the decolourising factor had protease activity towards myoglobin and haemoglobin. Complete inhibition of the enzyme by the inhibitor pepstatin A and the internal amino acid sequence classified the protein as an aspartic protease. The enzyme limitedly hydrolysed myoglobin between 1-Met and 2-Gly, 43-Lys and 44-Phe, and 70-Leu and 71-Thr. The purified enzyme decolourised blood of Katsuwonus pelamis (bonito) and a slice of dried bonito. It is proposed that aspartic protease plays a role in the decolourisation of Katsuobushi by the hydrolysis of haem proteins that allows the released haem to aggregate in the dried bonito. © 2012 Society of Chemical Industry.

  16. Genetic relationships among strains of the Aspergillus niger aggregate

    DEFF Research Database (Denmark)

    Ferracin, L.M.; Frisvad, Jens Christian; Taniwaki, M.H.

    2009-01-01

    We analyzed the genetic relationships between 51 fungal isolates previously identified as A. niger aggregate, obtained from dried fruit samples from worldwide origin and 7 A. tubingensis obtained from Brazilian coffee beans samples. Greater fungal diversity was found in black sultanas. Aspergillus...... niger sensu stricto was the most prevalent species. It was found in all fruit substrates of all geographical origins. Based on Random Amplification of Polymorphic DNA (RAPD) and beta-tubulin sequences data two groups of A. niger were found. In spite of the small number of isolates from Group IV...

  17. Mutant breeding of Aspergillus niger irradiated by 12C6+ for hyper citric acid

    International Nuclear Information System (INIS)

    Hu Wei; Li Wenjian; Chen Jihong; Liu Jing; Wang Shuyang; Wang Jufang; Lu Dong

    2014-01-01

    In this study, strains of Aspergillus niger No.4 for hyper citric acid were irradiated to different doses by 80 MeV/u 12 C 6+ ion beams. Seven mutant strains showed marked citric acid over-production records and faster productivity than initial Aspergillus niger No.4 by shaking flash fermentation. The maximum product yield was 132.8 gL -1 (the H4002 strain) being a 8.8% increase to the initial strain. The scale-up experiment was carried out in a 100 L bioreactor. The mutant H4002 can accumulate 187gL -1 product yield of citric acid from starch liquefying supernatant. The productivity of citric acid was 2.75 g L -1 h -1 . So, the mutant H4002 possesses rapid sugar katabolism for producing citric acid. Meanwhile, the pellet morphology kept compact and round during the whole submerged fermentation, which was suited to produce citric acid. The results indicate that mutant H4002 has potential ability to produce citric acid rapidly. (authors)

  18. Efficient degradation of tannic acid by black Aspergillus species

    NARCIS (Netherlands)

    Diepeningen, van A.D.; Debets, A.J.M.; Varga, J.; Gaag, van der M.; Swart, K.; Hoekstra, R.F.

    2004-01-01

    A set of aspergillus strains from culture collections and wild-type black aspergilli isolated on non-selective media were used to validate the use of media with 20 % tannic acid for exclusive and complete selection of the black aspergilli. The 20% tannic acid medium proved useful for both

  19. Efficient degradation of tannic acid by black Aspergillus species

    NARCIS (Netherlands)

    Van Diepeningen, Anne D; Debets, Alfons J M; Varga, Janos; van der Gaag, Marijn; Swart, Klaas; Hoekstra, Rolf F

    A set of aspergillus strains from culture collections and wild-type black aspergilli isolated on non-selective media were used to validate the use of media with 20% tannic acid for exclusive and complete selection of the black aspergilli. The 20% tannic acid medium proved useful for both

  20. Removal of trace element by isolates of Aspergillus brasiliensis ...

    African Journals Online (AJOL)

    Coffee beans processing generates a large volume of wastewater composed of trace elements which can be detrimental to human health. The present study aimed at evaluating the capacity of strains of Aspergillus brasiliensis and Penicillium citrinum in tolerating and removing trace elements namely: Cu, Mn and Zn from ...

  1. Experimental study of Aspergillus flavus fungus from uranium mines

    International Nuclear Information System (INIS)

    Kusak, V.

    1982-01-01

    Cultivation is discussed of fungus strain Aspergillus flavus obtained from materials from uranium mines. It was found that an addition of 0.6 g of uranium in form of uranyl acetate or of 0.6 g of thorium in form on thorium nitrate in 1000 ml of the standard medium had stimulating effects on the growth and sporulation of Aspergillus flavus. Irradiating the cultivated fungus through a polyethylene foil did not show a stimulating effect. It is stated that uranium and its daughters must be directly present in the culture medium for their stimulating effect on growth and sporulation to manifest itself. (H.S.)

  2. Polyphasic taxonomy of Aspergillus section Aspergillus (formerly Eurotium, and its occurrence in indoor environments and food

    Directory of Open Access Journals (Sweden)

    A.J. Chen

    2017-09-01

    Full Text Available Aspergillus section Aspergillus (formerly the genus Eurotium includes xerophilic species with uniseriate conidiophores, globose to subglobose vesicles, green conidia and yellow, thin walled eurotium-like ascomata with hyaline, lenticular ascospores. In the present study, a polyphasic approach using morphological characters, extrolites, physiological characters and phylogeny was applied to investigate the taxonomy of this section. Over 500 strains from various culture collections and new isolates obtained from indoor environments and a wide range of substrates all over the world were identified using calmodulin gene sequencing. Of these, 163 isolates were subjected to molecular phylogenetic analyses using sequences of ITS rDNA, partial β-tubulin (BenA, calmodulin (CaM and RNA polymerase II second largest subunit (RPB2 genes. Colony characteristics were documented on eight cultivation media, growth parameters at three incubation temperatures were recorded and micromorphology was examined using light microscopy as well as scanning electron microscopy to illustrate and characterize each species. Many specific extrolites were extracted and identified from cultures, including echinulins, epiheveadrides, auroglaucins and anthraquinone bisanthrons, and to be consistent in strains of nearly all species. Other extrolites are species-specific, and thus valuable for identification. Several extrolites show antioxidant effects, which may be nutritionally beneficial in food and beverages. Important mycotoxins in the strict sense, such as sterigmatocystin, aflatoxins, ochratoxins, citrinin were not detected despite previous reports on their production in this section. Adopting a polyphasic approach, 31 species are recognized, including nine new species. ITS is highly conserved in this section and does not distinguish species. All species can be differentiated using CaM or RPB2 sequences. For BenA, Aspergillus brunneus and A. niveoglaucus share identical

  3. Highly efficient gene targeting in Aspergillus oryzae industrial strains under ligD mutation introduced by genome editing: Strain-specific differences in the effects of deleting EcdR, the negative regulator of sclerotia formation.

    Science.gov (United States)

    Nakamura, Hidetoshi; Katayama, Takuya; Okabe, Tomoya; Iwashita, Kazuhiro; Fujii, Wataru; Kitamoto, Katsuhiko; Maruyama, Jun-Ichi

    2017-07-11

    Numerous strains of Aspergillus oryzae are industrially used for Japanese traditional fermentation and for the production of enzymes and heterologous proteins. In A. oryzae, deletion of the ku70 or ligD genes involved in non-homologous end joining (NHEJ) has allowed high gene targeting efficiency. However, this strategy has been mainly applied under the genetic background of the A. oryzae wild strain RIB40, and it would be laborious to delete the NHEJ genes in many A. oryzae industrial strains, probably due to their low gene targeting efficiency. In the present study, we generated ligD mutants from the A. oryzae industrial strains by employing the CRISPR/Cas9 system, which we previously developed as a genome editing method. Uridine/uracil auxotrophic strains were generated by deletion of the pyrG gene, which was subsequently used as a selective marker. We examined the gene targeting efficiency with the ecdR gene, of which deletion was reported to induce sclerotia formation under the genetic background of the strain RIB40. As expected, the deletion efficiencies were high, around 60~80%, in the ligD mutants of industrial strains. Intriguingly, the effects of the ecdR deletion on sclerotia formation varied depending on the strains, and we found sclerotia-like structures under the background of the industrial strains, which have never been reported to form sclerotia. The present study demonstrates that introducing ligD mutation by genome editing is an effective method allowing high gene targeting efficiency in A. oryzae industrial strains.

  4. Identification of resistance to Aspergillus flavus infection in cotton germplasm

    Science.gov (United States)

    Natural resistance of in cottonseed to Aspergillus flavus infection has not been explored to date. A green fluorescent protein (GFP) expressing -70 strain was used to assess the resistance of seed from thirty five35 cotton varieties including representatives from Gossypium arboreum, G. barbadense, a...

  5. Aspergillus flavus aswA, a gene homolog of Aspergillus nidulans oefC, regulates sclerotial development and biosynthesis of sclerotium-associated secondary metabolites

    Science.gov (United States)

    Aspergillus flavus aswA (AFLA_085170) is a gene encoding a Zn(II)2Cys6 DNA-binding domain. Partial deletion of aswA yielded strains that made a truncated gene transcript and generated a fungus that produced a greatly increased number of sclerotia. These sclerotia were odd-shaped and non-pigmented (w...

  6. Aspergillus bertholletius sp. nov. from Brazil nuts.

    Directory of Open Access Journals (Sweden)

    Marta H Taniwaki

    Full Text Available During a study on the mycobiota of brazil nuts (Bertholletia excelsa in Brazil, a new Aspergillus species, A. bertholletius, was found, and is described here. A polyphasic approach was applied using morphological characters, extrolite data as well as partial β-tubulin, calmodulin and ITS sequences to characterize this taxon. A. bertholletius is represented by nineteen isolates from samples of brazil nuts at various stages of production and soil close to Bertholletia excelsa trees. The following extrolites were produced by this species: aflavinin, cyclopiazonic acid, kojic acid, tenuazonic acid and ustilaginoidin C. Phylogenetic analysis using partial β-tubulin and camodulin gene sequences showed that A. bertholletius represents a new phylogenetic clade in Aspergillus section Flavi. The type strain of A. bertholletius is CCT 7615 ( = ITAL 270/06 = IBT 29228.

  7. Aspergillus bertholletius sp. nov. from Brazil Nuts

    Science.gov (United States)

    Taniwaki, Marta H.; Pitt, John I.; Iamanaka, Beatriz T.; Sartori, Daniele; Copetti, Marina V.; Balajee, Arun; Fungaro, Maria Helena P.; Frisvad, Jens C.

    2012-01-01

    During a study on the mycobiota of brazil nuts (Bertholletia excelsa) in Brazil, a new Aspergillus species, A. bertholletius, was found, and is described here. A polyphasic approach was applied using morphological characters, extrolite data as well as partial β-tubulin, calmodulin and ITS sequences to characterize this taxon. A. bertholletius is represented by nineteen isolates from samples of brazil nuts at various stages of production and soil close to Bertholletia excelsa trees. The following extrolites were produced by this species: aflavinin, cyclopiazonic acid, kojic acid, tenuazonic acid and ustilaginoidin C. Phylogenetic analysis using partial β-tubulin and camodulin gene sequences showed that A. bertholletius represents a new phylogenetic clade in Aspergillus section Flavi. The type strain of A. bertholletius is CCT 7615 ( = ITAL 270/06 = IBT 29228). PMID:22952594

  8. Random mutagenesis of aspergillus niger and process optimization for enhanced production of glucose oxidase

    International Nuclear Information System (INIS)

    Haq, I.; Nawaz, A.; Mukhtar, A.N.H.; Mansoor, H.M.Z.; Ameer, S.M.

    2014-01-01

    The study deals with the improvement of wild strain Aspergillus niger IIB-31 through random mutagenesis using chemical mutagens. The main aim of the work was to enhance the glucose oxidase (GOX) yield of wild strain (24.57+-0.01 U/g of cell mass) through random mutagenesis and process optimization. The wild strain of Aspergillus niger IIB-31 was treated with chemical mutagens such as Ethyl methane sulphonate (EMS) and nitrous acid for this purpose. Mutagen treated 98 variants indicating the positive results were picked and screened for the glucose oxidase production using submerged fermentation. EMS treated E45 mutant strain gave the highest glucose oxidase production (69.47 + 0.01 U/g of cell mass), which was approximately 3-folds greater than the wild strain IIB-31. The preliminary cultural conditions for the production of glucose oxidase using submerged fermentation from strain E45 were also optimized. The highest yield of GOD was obtained using 8% glucose as carbon and 0.3% peptone as nitrogen source at a medium pH of 7.0 after an incubation period of 72 hrs at 30 degree. (author)

  9. Secondary metabolite profiles and antifungal drug susceptibility of Aspergillus fumigatus and closely related species, Aspergillus lentulus, Aspergillus udagawae, and Aspergillus viridinutans.

    Science.gov (United States)

    Tamiya, Hiroyuki; Ochiai, Eri; Kikuchi, Kazuyo; Yahiro, Maki; Toyotome, Takahito; Watanabe, Akira; Yaguchi, Takashi; Kamei, Katsuhiko

    2015-05-01

    The incidence of Aspergillus infection has been increasing in the past few years. Also, new Aspergillus fumigatus-related species, namely Aspergillus lentulus, Aspergillus udagawae, and Aspergillus viridinutans, were shown to infect humans. These fungi exhibit marked morphological similarities to A. fumigatus, albeit with different clinical courses and antifungal drug susceptibilities. The present study used liquid chromatography/time-of-flight mass spectrometry to identify the secondary metabolites secreted as virulence factors by these Aspergillus species and compared their antifungal susceptibility. The metabolite profiles varied widely among A. fumigatus, A. lentulus, A. udagawae, and A. viridinutans, producing 27, 13, 8, and 11 substances, respectively. Among the mycotoxins, fumifungin, fumiquinazoline A/B and D, fumitremorgin B, gliotoxin, sphingofungins, pseurotins, and verruculogen were only found in A. fumigatus, whereas auranthine was only found in A. lentulus. The amount of gliotoxin, one of the most abundant mycotoxins in A. fumigatus, was negligible in these related species. In addition, they had decreased susceptibility to antifungal agents such as itraconazole and voriconazole, even though metabolites that were shared in the isolates showing higher minimum inhibitory concentrations than epidemiological cutoff values were not detected. These strikingly different secondary metabolite profiles may lead to the development of more discriminative identification protocols for such closely related Aspergillus species as well as improved treatment outcomes. Copyright © 2015 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  10. Ribosomal subunit protein typing using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) for the identification and discrimination of Aspergillus species.

    Science.gov (United States)

    Nakamura, Sayaka; Sato, Hiroaki; Tanaka, Reiko; Kusuya, Yoko; Takahashi, Hiroki; Yaguchi, Takashi

    2017-04-26

    Accurate identification of Aspergillus species is a very important subject. Mass spectral fingerprinting using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is generally employed for the rapid identification of fungal isolates. However, the results are based on simple mass spectral pattern-matching, with no peak assignment and no taxonomic input. We propose here a ribosomal subunit protein (RSP) typing technique using MALDI-TOF MS for the identification and discrimination of Aspergillus species. The results are concluded to be phylogenetic in that they reflect the molecular evolution of housekeeping RSPs. The amino acid sequences of RSPs of genome-sequenced strains of Aspergillus species were first verified and compared to compile a reliable biomarker list for the identification of Aspergillus species. In this process, we revealed that many amino acid sequences of RSPs (about 10-60%, depending on strain) registered in the public protein databases needed to be corrected or newly added. The verified RSPs were allocated to RSP types based on their mass. Peak assignments of RSPs of each sample strain as observed by MALDI-TOF MS were then performed to set RSP type profiles, which were then further processed by means of cluster analysis. The resulting dendrogram based on RSP types showed a relatively good concordance with the tree based on β-tubulin gene sequences. RSP typing was able to further discriminate the strains belonging to Aspergillus section Fumigati. The RSP typing method could be applied to identify Aspergillus species, even for species within section Fumigati. The discrimination power of RSP typing appears to be comparable to conventional β-tubulin gene analysis. This method would therefore be suitable for species identification and discrimination at the strain to species level. Because RSP typing can characterize the strains within section Fumigati, this method has potential as a powerful and reliable tool in

  11. Triazole Resistance in Aspergillus spp.: A Worldwide Problem?

    Science.gov (United States)

    Rivero-Menendez, Olga; Alastruey-Izquierdo, Ana; Mellado, Emilia; Cuenca-Estrella, Manuel

    2016-01-01

    Since the first description of an azole-resistant A. fumigatus strain in 1997, there has been an increasing number of papers describing the emergence of azole resistance. Firstly reported in the USA and soon after in Europe, it has now been described worldwide, challenging the management of human aspergillosis. The main mechanism of resistance is the modification of the azole target enzyme: 14-α sterol demethylase, encoded by the cyp51A gene; although recently, other resistance mechanisms have also been implicated. In addition, a shift in the epidemiology has been noted with other Aspergillus species (mostly azole resistant) increasingly being reported as causative agents of human disease. This paper reviews the current situation of Aspergillus azole resistance and its implications in the clinical setting. PMID:29376938

  12. Aspergillus flavus: human pathogen, allergen and mycotoxin producer.

    Science.gov (United States)

    Hedayati, M T; Pasqualotto, A C; Warn, P A; Bowyer, P; Denning, D W

    2007-06-01

    Aspergillus infections have grown in importance in the last years. However, most of the studies have focused on Aspergillus fumigatus, the most prevalent species in the genus. In certain locales and hospitals, Aspergillus flavus is more common in air than A. fumigatus, for unclear reasons. After A. fumigatus, A. flavus is the second leading cause of invasive aspergillosis and it is the most common cause of superficial infection. Experimental invasive infections in mice show A. flavus to be 100-fold more virulent than A. fumigatus in terms of inoculum required. Particularly common clinical syndromes associated with A. flavus include chronic granulomatous sinusitis, keratitis, cutaneous aspergillosis, wound infections and osteomyelitis following trauma and inoculation. Outbreaks associated with A. flavus appear to be associated with single or closely related strains, in contrast to those associated with A. fumigatus. In addition, A. flavus produces aflatoxins, the most toxic and potent hepatocarcinogenic natural compounds ever characterized. Accurate species identification within Aspergillus flavus complex remains difficult due to overlapping morphological and biochemical characteristics, and much taxonomic and population genetics work is necessary to better understand the species and related species. The flavus complex currently includes 23 species or varieties, including two sexual species, Petromyces alliaceus and P. albertensis. The genome of the highly related Aspergillus oryzae is completed and available; that of A. flavus in the final stages of annotation. Our understanding of A. flavus lags far behind that of A. fumigatus. Studies of the genomics, taxonomy, population genetics, pathogenicity, allergenicity and antifungal susceptibility of A. flavus are all required.

  13. Kinetic characterization of glucose aerodehydrogenase from Aspergillus niger EMS-150-F after optimizing the dose of mutagen for enhanced production of enzyme

    OpenAIRE

    Umbreen, Huma; Zia, Muhammad Anjum; Rasul, Samreen

    2013-01-01

    In the present study enhanced production of glucose aerodehydrogenase from Aspergillus niger has been achieved after optimizing the dose of chemical mutagen ethyl methane sulfonate (EMS) that has not been reported earlier. Different doses of mutagen were applied and a strain was developed basing upon the best production. The selected strain Aspergillus niger EMS-150-F was optimized for nutrient requirements in order to produce enzyme through fermentation and the results showed the best yield ...

  14. Polyphasic taxonomy of Aspergillus section Aspergillus (formerly Eurotium), and its occurrence in indoor environments and food

    DEFF Research Database (Denmark)

    Chen, A.J.; Hubka, Vit; Frisvad, Jens Christian

    2017-01-01

    , epiheveadrides, auroglaucins and anthraquinone bisanthrons, and to be consistent in strains of nearly all species. Other extrolites are species-specific, and thus valuable for identification. Several extrolites show antioxidant effects, which may be nutritionally beneficial in food and beverages. Important...... not distinguish species. All species can be differentiated using CaM or RPB2 sequences. For BenA, Aspergillus brunneus and A. niveoglaucus share identical sequences. Ascospores and conidia morphologyw, growth rates at different temperatures are most useful characters for phenotypic species identification....

  15. Aspergillus section Fumigati typing by PCR-restriction fragment polymorphism.

    Science.gov (United States)

    Staab, Janet F; Balajee, S Arunmozhi; Marr, Kieren A

    2009-07-01

    Recent studies have shown that there are multiple clinically important members of the Aspergillus section Fumigati that are difficult to distinguish on the basis of morphological features (e.g., Aspergillus fumigatus, A. lentulus, and Neosartorya udagawae). Identification of these organisms may be clinically important, as some species vary in their susceptibilities to antifungal agents. In a prior study, we utilized multilocus sequence typing to describe A. lentulus as a species distinct from A. fumigatus. The sequence data show that the gene encoding beta-tubulin, benA, has high interspecies variability at intronic regions but is conserved among isolates of the same species. These data were used to develop a PCR-restriction fragment length polymorphism (PCR-RFLP) method that rapidly and accurately distinguishes A. fumigatus, A. lentulus, and N. udagawae, three major species within the section Fumigati that have previously been implicated in disease. Digestion of the benA amplicon with BccI generated unique banding patterns; the results were validated by screening a collection of clinical strains and by in silico analysis of the benA sequences of Aspergillus spp. deposited in the GenBank database. PCR-RFLP of benA is a simple method for the identification of clinically important, similar morphotypes of Aspergillus spp. within the section Fumigati.

  16. Aspergillus Section Fumigati Typing by PCR-Restriction Fragment Polymorphism▿

    Science.gov (United States)

    Staab, Janet F.; Balajee, S. Arunmozhi; Marr, Kieren A.

    2009-01-01

    Recent studies have shown that there are multiple clinically important members of the Aspergillus section Fumigati that are difficult to distinguish on the basis of morphological features (e.g., Aspergillus fumigatus, A. lentulus, and Neosartorya udagawae). Identification of these organisms may be clinically important, as some species vary in their susceptibilities to antifungal agents. In a prior study, we utilized multilocus sequence typing to describe A. lentulus as a species distinct from A. fumigatus. The sequence data show that the gene encoding β-tubulin, benA, has high interspecies variability at intronic regions but is conserved among isolates of the same species. These data were used to develop a PCR-restriction fragment length polymorphism (PCR-RFLP) method that rapidly and accurately distinguishes A. fumigatus, A. lentulus, and N. udagawae, three major species within the section Fumigati that have previously been implicated in disease. Digestion of the benA amplicon with BccI generated unique banding patterns; the results were validated by screening a collection of clinical strains and by in silico analysis of the benA sequences of Aspergillus spp. deposited in the GenBank database. PCR-RFLP of benA is a simple method for the identification of clinically important, similar morphotypes of Aspergillus spp. within the section Fumigati. PMID:19403766

  17. Genome-scale analysis of the high-efficient protein secretion system of Aspergillus oryzae

    DEFF Research Database (Denmark)

    Liu, Lifang; Feizi, Amir; Osterlund, Tobias

    2014-01-01

    related fungal species such as Aspergillus nidulans and Aspergillus niger. To evaluate the defined component list, we performed transcriptome analysis on three a-amylase over-producing strains with varying levels of secretion capacities. Specifically, secretory components involved in the ER......Background: The koji mold, Aspergillus oryzae is widely used for the production of industrial enzymes due to its particularly high protein secretion capacity and ability to perform post-translational modifications. However, systemic analysis of its secretion system is lacking, generally due...... to the poorly annotated proteome. Results: Here we defined a functional protein secretory component list of A. oryzae using a previously reported secretory model of S. cerevisiae as scaffold. Additional secretory components were obtained by blast search with the functional components reported in other closely...

  18. VeA of Aspergillus niger increases spore dispersing capacity by impacting conidiophore architecture.

    Science.gov (United States)

    Wang, Fengfeng; Dijksterhuis, Jan; Wyatt, Timon; Wösten, Han A B; Bleichrodt, Robert-Jan

    2015-01-01

    Aspergillus species are highly abundant fungi worldwide. Their conidia are among the most dominant fungal spores in the air. Conidia are formed in chains on the vesicle of the asexual reproductive structure called the conidiophore. Here, it is shown that the velvet protein VeA of Aspergillus niger maximizes the diameter of the vesicle and the spore chain length. The length and width of the conidiophore stalk and vesicle were reduced nearly twofold in a ΔveA strain. The latter implies a fourfold reduced surface area to develop chains of spores. Over and above this, the conidial chain length was approximately fivefold reduced. The calculated 20-fold reduction in formation of conidia by ΔveA fits the 8- to 17-fold decrease in counted spore numbers. Notably, morphology of the ΔveA conidiophores of A. niger was very similar to that of wild-type Aspergillus sydowii. This suggests that VeA is key in conidiophore architecture diversity in the fungal kingdom. The finding that biomass formation of the A. niger ΔveA strain was reduced twofold shows that VeA not only impacts dispersion capacity but also colonization capacity of A. niger.

  19. Biodegradation of HDPE by Aspergillus spp. from marine ecosystem of Gulf of Mannar, India.

    Science.gov (United States)

    Sangeetha Devi, Rajendran; Rajesh Kannan, Velu; Nivas, Duraisamy; Kannan, Kanthaiah; Chandru, Sekar; Robert Antony, Arokiaswamy

    2015-07-15

    High density polyethylene (HDPE) is the most commonly found non-degradable solid waste among the polyethylene. In this present study, HDPE degrading various fungal strains were isolated from the polyethylene waste dumped marine coastal area and screened under in vitro condition. Based on weight loss and FT-IR Spectrophotometric analysis, two fungal strains designated as VRKPT1 and VRKPT2 were found to be efficient in HDPE degradation. Through the sequence analysis of ITS region homology, the isolated fungi were identified as Aspergillus tubingensis VRKPT1 and Aspergillus flavus VRKPT2. The biofilm formation observed under epifluorescent microscope had shown the viability of fungal strains even after one month of incubation. The biodegradation of HDPE film nature was further investigated through SEM analysis. HDPE poses severe environmental threats and hence the ability of fungal isolates was proved to utilize virgin polyethylene as the carbon source without any pre-treatment and pro-oxidant additives. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. A trispecies Aspergillus microarray: Comparative transcriptomics of three Aspergillus species

    DEFF Research Database (Denmark)

    Andersen, Mikael Rørdam; Vongsangnak, Wanwipa; Panagiotou, Gianni

    2008-01-01

    The full-genome sequencing of the filamentous fungi Aspergillus nidulans, Aspergillus niger, and Aspergillus oryzae has opened possibilities for studying the cellular physiology of these fungi on a systemic level. As a tool to explore this, we are making available an Affymetrix GeneChip developed...... data identified 23 genes to be a conserved response across Aspergillus sp., including the xylose transcriptional activator XlnR. A promoter analysis of the up-regulated genes in all three species indicates the conserved XInR-binding site to be 5'-GGNTAAA-3'. The composition of the conserved gene......-set suggests that xylose acts as a molecule, indicating the presence of complex carbohydrates such as hemicellulose, and triggers an array of degrading enzymes. With this case example, we present a validated tool for transcriptome analysis of three Aspergillus species and a methodology for conducting cross...

  1. Co-inoculation of aflatoxigenic and non-aflatoxigenic strains of Aspergillus flavus to study fungal invasion, colonization, and competition in maize kernels

    Directory of Open Access Journals (Sweden)

    Zuzana eHruska

    2014-03-01

    Full Text Available A currently utilized pre-harvest biocontrol method involves field inoculations with non-aflatoxigenic Aspergillus flavus strains, a tactic shown to strategically suppress native aflatoxin-producing strains and effectively decrease aflatoxin contamination in corn. The present in situ study focuses on tracking the invasion and colonization of an aflatoxigenic A. flavus strain (AF70, labeled with green fluorescent protein (GFP, in the presence of a non-aflatoxigenic A. flavus biocontrol strain (AF36 to better understand the competitive interaction between these two strains in seed tissue of corn (Zea mays. Corn kernels that had been co-inoculated with GFP-labeled AF70 and wild-type AF36 were cross-sectioned and observed under UV and blue light to determine the outcome of competition between these strains. After imaging, all kernels were analyzed for aflatoxin levels. There appeared to be a population difference between the co-inoculated AF70-GFP+AF36 and the individual AF70-GFP tests, both visually and with pixel count analysis. The GFP allowed us to observe that AF70-GFP inside the kernels was suppressed up to 82% when co-inoculated with AF36 indicating that AF36 inhibited progression of AF70-GFP. This was in agreement with images taken of whole kernels where AF36 exhibited a more robust external growth compared to AF70-GFP. The suppressed growth of AF70-GFP was reflected in a corresponding (up to 73% suppression in aflatoxin levels. Our results indicate that the decrease in aflatoxin production correlated with population depression of the aflatoxigenic fungus by the biocontrol strain supporting the theory of competitive exclusion through robust propagation and fast colonization by the non-aflatoxigenic fungus.

  2. Performance of Molecular Approaches for Aspergillus Detection and Azole Resistance Surveillance in Cystic Fibrosis

    Directory of Open Access Journals (Sweden)

    Hélène Guegan

    2018-03-01

    Full Text Available Aspergillus fumigatus triazole resistance is an emerging concern for treating chronically infected/colonized patients. This study sought to evaluate the performance of PCR assays to detect Aspergillus fungi together with azole resistance in sputum samples from cystic fibrosis (CF patients. In total, 119 sputum samples from 87 CF patients were prospectively processed for Aspergillus detection by means of mycological culture and four qPCR assays, 2 in-house methods and two commercial multiplex real-time PCR assays simultaneously detecting Aspergillus and the most relevant cyp51A gene mutations (MycoGENIE® and AsperGenius®. Azole susceptibility of A. fumigatus isolates was assessed using Etest® method and cyp51A gene mutation were characterized by sequencing. The overall rate of Aspergillus detection with the four qPCR assays ranged from 47.9 to 57.1%, contrasting with 42/119 (35.3% positive cultures with A. fumigatus. The high sensitivity of PCR on sputum could then contribute to more effective grading of Aspergillus disease in CF patients. Five out of 41 isolated strains (12.2% exhibited azole-resistant MIC patterns, three of which harbored cyp51A mutations and only 1/3 with the sequence TR34/L98H. Combined with culture, PCR assay achieved high sensitivity Aspergillus screening in CF samples. However, cyp51A targeting was only moderately effective for azole resistance monitoring, while Aspergillus resistance remains of great concern.

  3. Citric acid production from whey by fermentation using Aspergillus spp.

    Directory of Open Access Journals (Sweden)

    Óscar Julián Sánchez Toro

    2004-01-01

    Full Text Available Whey has become the main dairy-industry waste product, despite continuous efforts aimed at finding a way to use it. The aim of this research was to investigate citric acid production by submerged fermentation using Aspergillus genus fungi, using whey as substrate to take economical advantage of it and to reduce the environmental impact caused by discharging this by-product into nearby streams. The following three strains were used: A. carbonarius NRRL 368, A. carbonarius NRRL 67 and A. niger NRRL 3. The best adaptation medium for inoculum propagation was selected. Proposed experimental design for evaluating citric acid biosynthesis from whey modified through different treatments showed that the two A. carbonarius strains did not present significant differences in acid production whereas A. niger NRRL 3 reached higher concentration when evaporated, deproteinised and p-galactosidase lactose-hydrolysed whey was used. However, A. carbonarius gave higher average citric acid titres than those found for A. niger. This suggests the need for carrying out further research on it as a potential producing strain. Cell growth, substrate consumption and acid production kinetics in a 3-L stirred-tank bioreactor with aeration were developed in the case of A. niger; kinetics were simulated through non-structured mathematical models. Key words: Aspergilluscarbonarius, Aspergillus niger, bioreactor, simulation, p-galactosidase.

  4. Aspergillus ibericus : a new species of section nigri characterised by MALDI-TOF MS

    OpenAIRE

    Kallow, W.; Santos, Isabel; Erhard, M.; Serra, Rita; Venâncio, Armando; Lima, Nelson

    2006-01-01

    Strains from the new described species Aspergillus ibericus were characterised using MALDI-TOF MS and the results were compared with other related species of section Nigri. Fundação para a Ciência e a Tecnologia (FCT)

  5. Potential for the development of tolerance by Aspergillus amstelodami, A. repens and A. ruber after repeated exposure to potassium sorbate.

    Science.gov (United States)

    Viñas, I; Morlans, I; Sanchis, V

    1990-01-01

    Three strains of A. amstelodami, A. repens and A. ruber were exposed to various levels of potassium sorbate, and the MICs were determined. Selected strains of the molds were then repeatedly exposed to subinhibitory levels of the compound to determine whether increased tolerance might develop. The MIC of sorbate (pH 5.5 or 6.5) for 3 species of Aspergillus was 0.07%. Increasing levels of sorbate resulted in increasing growth suppression of the molds. The 3 Aspergillus species were tested for increased tolerance to potassium sorbate, and none was found. They developed a slight increase in tolerance dependent upon pH and the mold strain by subculturing at low levels of sorbate.

  6. Aspergillus fumigatus-Related Species in Clinical Practice.

    Science.gov (United States)

    Lamoth, Frédéric

    2016-01-01

    Aspergillus fumigatus is the main etiologic agent of invasive aspergillosis (IA). Other Aspergillus species belonging to the section Fumigati (A. fumigatus complex) may occasionally be the cause of IA. These strains are often misidentified, as they cannot be distinguished from A. fumigatus by conventional morphological analysis and sequencing methods. This lack of recognition may have important consequences as these A. fumigatus-related species often display some level of intrinsic resistance to azoles and other antifungal drugs. A. lentulus, A. udagawae, A. viridinutans, and A. thermomutatus (Neosartorya pseudofischeri) have been associated with refractory cases of IA. Microbiologists should be able to suspect the presence of these cryptic species behind a putative A. fumigatus isolate on the basis of some simple characteristics, such as defect in sporulation and/or unusual antifungal susceptibility profile. However, definitive species identification requires specific sequencing analyses of the beta-tubulin or calmodulin genes, which are not available in most laboratories. Multiplex PCR assays or matrix-assisted laser desorption ionization - time-of-flight mass spectrometry (MALDI-TOF MS) gave promising results for rapid and accurate distinction between A. fumigatus and other Aspergillus spp. of the section Fumigati in clinical practice. Improved diagnostic procedures and antifungal susceptibility testing may be helpful for the early detection and management of these particular IA cases.

  7. Polyphasic approach to the identification and characterization of aflatoxigenic strains of Aspergillus section Flavi isolated from peanuts and peanut-based products marketed in Malaysia.

    Science.gov (United States)

    Norlia, M; Jinap, S; Nor-Khaizura, M A R; Son, R; Chin, C K; Sardjono

    2018-05-31

    Peanuts are widely consumed as the main ingredient in many local dishes in Malaysia. However, the tropical climate in Malaysia (high temperature and humidity) favours the growth of fungi from Aspergillus section Flavi, especially during storage. Most of the species from this section, such as A. flavus, A. parasiticus and A. nomius, are natural producers of aflatoxins. Precise identification of local isolates and information regarding their ability to produce aflatoxins are very important to evaluate the safety of food marketed in Malaysia. Therefore, this study aimed to identify and characterize the aflatoxigenic and non-aflatoxigenic strains of Aspergillus section Flavi in peanuts and peanut-based products. A polyphasic approach, consisting of morphological and chemical characterizations was applied to 128 isolates originating from raw peanuts and peanut-based products. On the basis of morphological characters, 127 positively identified as Aspergillus flavus, and the other as A. nomius. Chemical characterization revealed six chemotype profiles which indicates diversity of toxigenic potential. About 58.6%, 68.5%, and 100% of the isolates are positive for aflatoxins, cyclopiazonic acid and aspergillic acid productions respectively. The majority of the isolates originating from raw peanut samples (64.8%) were aflatoxigenic, while those from peanut-based products were less toxigenic (39.1%). The precise identification of these species may help in developing control strategies for aflatoxigenic fungi and aflatoxin contamination in peanuts, especially during storage. These findings also highlight the possibility of the co-occurrence of other toxins, which could increase the potential toxic effects of peanuts. Copyright © 2018. Published by Elsevier B.V.

  8. Enhanced itaconic acid production in Aspergillus with increased LaeA expression

    Science.gov (United States)

    Dai, Ziyu; Baker, Scott E.

    2018-03-06

    Fungi, such as Aspergillus niger, having a dolichyl-P-Man:Man(5)GlcNAc(2)-PP-dolichyl mannosyltransferase (Alg3) gene genetic inactivation, increased expression of a loss of aflR expression A (LaeA), or both, are described. In some examples, such mutants have several phenotypes, including an increased production of citric acid relative to the parental strain. Methods of using the disclosed fungi to make citric acid are also described, as are compositions and kits including the disclosed fungi. Further described are Aspergillus terreus fungi overexpressing the LaeA gene and the use of such fungi for the production of itaconic acid.

  9. Post-genomic insights into the plant polysaccharide degradation potential of Aspergillus nidulans and comparison to Aspergillus niger and Aspergillus oryzae

    NARCIS (Netherlands)

    Coutinho, Pedro M; Andersen, Mikael R; Kolenova, Katarina; vanKuyk, Patricia A; Benoit, Isabelle; Gruben, Birgit S; Trejo-Aguilar, Blanca; Visser, Hans; van Solingen, Piet; Pakula, Tiina; Seiboth, Bernard; Battaglia, Evy; Aguilar-Osorio, Guillermo; de Jong, Jan F; Ohm, Robin A; Aguilar, Mariana; Henrissat, Bernard; Nielsen, Jens; Stålbrand, Henrik; de Vries, Ronald P

    The plant polysaccharide degradative potential of Aspergillus nidulans was analysed in detail and compared to that of Aspergillus niger and Aspergillus oryzae using a combination of bioinformatics, physiology and transcriptomics. Manual verification indicated that 28.4% of the A. nidulans ORFs

  10. Extracellular acid protease from Aspergillus niger I1: purification and ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-09-15

    Sep 15, 2009 ... A new strain of Aspergillus niger producing acid protease was isolated and identified by universal primers NL1 and .... Media were autoclaved at 120°C for 20 min. ... molecular weight calibration kit as markers consisting of bovine ... then removed by washing the gel three times with 100 mM ..... New York.

  11. [The first case of persistent vaginitis due to Aspergillus protuberus in an immunocompetent patient].

    Science.gov (United States)

    Borsa, Barış Ata; Özgün, Gonca; Houbraken, Jos; Ökmen, Fırat

    2015-01-01

    The vast majority of vaginal fungal infections are caused by Candida species. However, vaginitis cases caused by molds are extremely rare. Aspergillus protuberus is previously known as a member of Aspergillus section Versicolores which can cause opportunistic infections in immunocompromised patients, however it has recently been described as a seperate species. Although the members of Aspergillus section Versicolores have been isolated rarely in cases of pulmonary infections, eye infections, otomycosis, osteomyelitis and onycomycoses, to the best of our knowledge, there is no published case of human infection caused by A.protuberus. In this report, the first case of persistent vaginitis due to A.protuberus in an immunocompetent patient was presented. A 42-year-old female patient was admitted to our hospital with the complaints of pelvic pain, vaginal itching and discharge during one month. Her symptoms had been persistant despite of the miconazole nitrate and clotrimazole therapies for probable candidal vaginitis. Fungal structures such as branched, septate hyphae together with the conidial forms were seen in microscopic examination as in the cervical smear. Thereafter, a vaginal discharge sample was taken for microbiological evaluation and similar characteristics of fungal structures were observed in the microscopic examination as of cervical smear. Then, preliminary result was reported as Aspergillus spp. At the same time, the sample was plated on Sabouraud dextrose agar (SDA) in duplicate and incubated at room temperature and at 37°C. After 5 days, white, powdery and pure-looking fungal colonies were observed in SDA which was incubated at room temperature, while the other medium remained sterile. The culture was submitted to the CBS-KNAW Fungal Biodiversity Center for further characterization. Phenotypic identification showed that the isolated strain belonged to the Aspergillus section Versicolores. The strain was grown for 7 days on malt extract agar and then

  12. Efficient production of lignocellulolytic enzymes xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by the mutant strain Aspergillus awamori 2B.361 U2/1

    Directory of Open Access Journals (Sweden)

    Leda Maria Fortes Gottschalk

    2013-01-01

    Full Text Available The production of xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by Aspergillus awamori 2B.361 U2/1, a hyper producer of glucoamylase and pectinase, was evaluated using selected conditions regarding nitrogen nutrition. Submerged cultivations were carried out at 30 ºC and 200 rpm in growth media containing 30 g wheat bran/L as main carbon source and either yeast extract, ammonium sulfate, sodium nitrate or urea, as nitrogen sources; in all cases it was used a fixed molar carbon to molar nitrogen concentration of 10.3. The use of poor nitrogen sources favored the accumulation of xylanase, β-xylosidase and ferulic acid esterase to a peak concentrations of 44,880; 640 and 118 U/L, respectively, for sodium nitrate and of 34,580, 685 and 170 U/L, respectively, for urea. However, the highest β-glucosidase accumulation of 10,470 U/L was observed when the rich organic nitrogen source yeast extract was used. The maxima accumulation of filter paper activity, xylanase, β-xylosidase, ferulic acid esterase and β-glucosidase by A. awamori 2B.361 U2/1 was compared to that produced by Trichoderma reesei Rut-C30. The level of β-glucosidase was over 17-fold higher for the Aspergillus strain, whereas the levels of xylanase and β-xylosidase were over 2-fold higher. This strain also produced ferulic acid esterase (170 U/L, which was not detected in the T. reesei culture.

  13. Cissus quadrangularis mediated ecofriendly synthesis of copper oxide nanoparticles and its antifungal studies against Aspergillus niger, Aspergillus flavus.

    Science.gov (United States)

    Devipriya, Duraipandi; Roopan, Selvaraj Mohana

    2017-11-01

    Recently, non-toxic source mediated synthesis of metal and a metal oxide nanoparticle attains more attention due to key applicational responsibilities. This present report stated that the eco-friendly synthesis of copper oxide nanoparticles (CuO NPs) using Cissus quadrangularis (C. quadrangularis) plant extract. Further the eco-friendly synthesized CuO NPs were characterized using a number of analytical techniques. The observed results stated that the synthesized CuO NPs were spherical in shape with 30±2nm. Then the eco-friendly synthesized CuO NPs were subjected for anti-fungal against two strains namely Aspergillus niger (A. niger) resulted in 83% at 500ppm, 86% of inhibition at 1000ppm and Aspergillus flavus (A. flavus) resulted in 81% at 500ppm, 85% of inhibition at 1000ppm respectively. Despite the fact that compared to standard Carbendazim, eco-friendly synthesized CuO NPs exhibits better results were discussed in this manuscript. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Study of effect ultraviolet radiation on Aspergillus Flavus and Aspergillus Parasiticus

    International Nuclear Information System (INIS)

    Ghafourian, H.; Kafaei, F.; Raouf, J.B.

    2000-01-01

    In this article the results of ultraviolet radiation effects on Aspergillus Flavus and Aspergillus parasiticus to reach the quality control standards are presented. The purpose was to test the effect of ultraviolet radiation in 254 nanometer wavelength for fungi decontamination with respect to the exposure time of radiation and the distance between samples and radiation source. The ultraviolet radiation effects on plates containing Aspergillus Flavus and Aspergillus Parasiticus fungi were studied in the exposure time duration of 30, to 360 seconds of a fixed distance, and also for variable distances from 10 to 40 cm at a given exposure time. It is shown that in the exposure time of more than 360 second the ultraviolet radiation exposure highly decreases the number of Aspergillus Flavus and Aspergillus Parasiticus fungi colonies. By reducing the distance, the number of colonies decreases and it is minimized at a 10 cm distance in the time exposure of 360 second. The above results show that the ultraviolet radiation is an effective method for food decontamination and can be used in industry

  15. What Does Genetic Diversity of Aspergillus flavus Tell Us About Aspergillus oryzae?

    Science.gov (United States)

    Aspergillus flavus and Aspergillus oryzae belong to Aspergillus section Flavi. They are closely related and are of significant economic importance. The former species has the ability to produce harmful aflatoxins while the latter is widely used in food fermentation and industrial enzyme production. ...

  16. UV mutagenesis of aspergillus niger for enzyme production in submerged fermentation

    International Nuclear Information System (INIS)

    Irfan, M.; Syed, Q.; Javed, J.

    2011-01-01

    The present study was conducted to improve the enzyme production from Aspergillus niger using UV mutation. Submerged fermentation was carried out in 250 ml Erlenmeyer flask using Vogel's media at 30 deg. C for six days. Results of this study revealed that UV-mutation enhanced CM Case activity up to two times while FPase activity up to three times as compared to the parental strain. For avicelase, xylanase and fungal biomass production, UV radiation has slight effect as compared to parental strain. (author)

  17. Soybean hull induced production of carbohydrases and protease among Aspergillus and their effectiveness in soy flour carbohydrate and protein separation.

    Science.gov (United States)

    Li, Qian; Loman, Abdullah Al; Coffman, Anthony M; Ju, Lu-Kwang

    2017-04-20

    Soybean hull consists mainly of three major plant carbohydrates, i.e., cellulose, hemicellulose and pectin. It is inexpensive and a good potential substrate for carbohydrase production because it is capable of inducing a complete spectrum of activities to hydrolyze complex biomass. Aspergillus is known for carbohydrase production but no studies have evaluated and compared, among Aspergillus species and strains, the soybean hull induced production of various carbohydrases. In this study, A. aculeatus, A. cinnamomeus, A. foetidus, A. phoenicis and 11 A. niger strains were examined together with T. reesei Rut C30, another known carbohydrase producer. The carbohydrases evaluated included pectinase, polygalacturonase, xylanase, cellulase, α-galactosidase and sucrase. Growth morphology and pH profiles were also followed. Among Aspergillus strains, morphology was found to correlate with both carbohydrase production and pH decrease profile. Filamentous strains gave higher carbohydrase production while causing slower pH decrease. The enzyme broths produced were also tested for separation of soy flour carbohydrate and protein. Defatted soy flour contains about 53% protein and 32% carbohydrate. The enzymatic treatment can increase protein content and remove indigestible oligo-/poly-saccharides, and improve use of soy flour in feed and food. Protease production by different strains was therefore also compared for minimizing protein degradation. A. niger NRRL 322 and A. foetidus NRRL 341 were found to be the most potent strains that produced maximal carbohydrases and minimal protease under soybean hull induction. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Rewiring a secondary metabolite pathway towards itaconic acid production in Aspergillus niger.

    Science.gov (United States)

    Hossain, Abeer H; Li, An; Brickwedde, Anja; Wilms, Lars; Caspers, Martien; Overkamp, Karin; Punt, Peter J

    2016-07-28

    The industrially relevant filamentous fungus Aspergillus niger is widely used in industry for its secretion capabilities of enzymes and organic acids. Biotechnologically produced organic acids promise to be an attractive alternative for the chemical industry to replace petrochemicals. Itaconic acid (IA) has been identified as one of the top twelve building block chemicals which have high potential to be produced by biotechnological means. The IA biosynthesis cluster (cadA, mttA and mfsA) has been elucidated in its natural producer Aspergillus terreus and transferred to A. niger to enable IA production. Here we report the rewiring of a secondary metabolite pathway towards further improved IA production through the overexpression of a putative cytosolic citrate synthase citB in a A. niger strain carrying the IA biosynthesis cluster. We have previously shown that expression of cadA from A. terreus results in itaconic acid production in A. niger AB1.13, albeit at low levels. This low-level production is boosted fivefold by the overexpression of mttA and mfsA in itaconic acid producing AB1.13 CAD background strains. Controlled batch cultivations with AB1.13 CAD + MFS + MTT strains showed increased production of itaconic acid compared with AB1.13 CAD strain. Moreover, preliminary RNA-Seq analysis of an itaconic acid producing AB1.13 CAD strain has led to the identification of the putative cytosolic citrate synthase citB which was induced in an IA producing strain. We have overexpressed citB in a AB1.13 CAD + MFS + MTT strain and by doing so hypothesize to have targeted itaconic acid production to the cytosolic compartment. By overexpressing citB in AB1.13 CAD + MFS + MTT strains in controlled batch cultivations we have achieved highly increased titers of up to 26.2 g/L IA with a productivity of 0.35 g/L/h while no CA was produced. Expression of the IA biosynthesis cluster in Aspergillus niger AB1.13 strain enables IA production. Moreover, in the AB1.13 CAD

  19. Epidemiological and Genomic Landscape of Azole Resistance Mechanisms in Aspergillus Fungi

    Science.gov (United States)

    Hagiwara, Daisuke; Watanabe, Akira; Kamei, Katsuhiko; Goldman, Gustavo H.

    2016-01-01

    Invasive aspergillosis is a life-threatening mycosis caused by the pathogenic fungus Aspergillus. The predominant causal species is Aspergillus fumigatus, and azole drugs are the treatment of choice. Azole drugs approved for clinical use include itraconazole, voriconazole, posaconazole, and the recently added isavuconazole. However, epidemiological research has indicated that the prevalence of azole-resistant A. fumigatus isolates has increased significantly over the last decade. What is worse is that azole-resistant strains are likely to have emerged not only in response to long-term drug treatment but also because of exposure to azole fungicides in the environment. Resistance mechanisms include amino acid substitutions in the target Cyp51A protein, tandem repeat sequence insertions at the cyp51A promoter, and overexpression of the ABC transporter Cdr1B. Environmental azole-resistant strains harboring the association of a tandem repeat sequence and punctual mutation of the Cyp51A gene (TR34/L98H and TR46/Y121F/T289A) have become widely disseminated across the world within a short time period. The epidemiological data also suggests that the number of Aspergillus spp. other than A. fumigatus isolated has risen. Some non-fumigatus species intrinsically show low susceptibility to azole drugs, imposing the need for accurate identification, and drug susceptibility testing in most clinical cases. Currently, our knowledge of azole resistance mechanisms in non-fumigatus Aspergillus species such as A. flavus, A. niger, A. tubingensis, A. terreus, A. fischeri, A. lentulus, A. udagawae, and A. calidoustus is limited. In this review, we present recent advances in our understanding of azole resistance mechanisms particularly in A. fumigatus. We then provide an overview of the genome sequences of non-fumigatus species, focusing on the proteins related to azole resistance mechanisms. PMID:27708619

  20. Ohcratoxin producing Aspergillus spp. Isolated from tropical soils in Sarawak, Malaysia

    Directory of Open Access Journals (Sweden)

    J.S.S. Seelan

    2010-03-01

    Full Text Available Aspergillus strains isolated from tropical soils were selected for additional characterization and for ochratoxin analysis, which was determined by ELISA method and high performance liquid chromatography (HPLC profiles. Because of its great morphological variability and mycotoxin production availability, 18 isolates of Aspergillus species were selected for this study. Only two isolates of these tropical soils, A. sulphureus and A. carbonarius, showed positive results for ohcratoxin (OA in lower concentration (0.05-0.10 µg/ml. Ochratoxin production by these species was confirmed by high performance liquid chromatography. HPLC analysis for ochratoxin producing A. sulphureus and A. carbonarius showed retention time, Rt value = 4.417 and Rt value = 4.081 respectively.

  1. Conversion of fusaric acid to fusarinol by Aspergillus niger: A detoxification reaction

    Science.gov (United States)

    The fungus Fusarium oxysporum causes wilt diseases of plants and produces a potent phytotoxin fusaric acid (FA) which is also toxic to many microorganisms. An Aspergillus strain with high tolerance to FA was isolated from soil. HPLC analysis of culture filtrates from A. niger grown with the addition...

  2. (HN1) strain of Aspergillus niger

    African Journals Online (AJOL)

    login123

    2016-09-26

    Sep 26, 2016 ... olive oil) increased the production of lipase up to 20% in case of both the strains. The production of ... insoluble triacylglycerols to generate free fatty acids, mono and ... Two fermentation processes, including solid state.

  3. Evaluation of MIC Strip Isavuconazole test for susceptibility testing of wild-type and non-wild-type Aspergillus fumigatus isolates

    DEFF Research Database (Denmark)

    Arendrup, Maiken Cavling; Verweij, Paul; Nielsen, Henrik Vedel

    2017-01-01

    We evaluated the MIC Strip Isavuconazole test against EUCAST E.Def 9.3 by using 40 wild-type and 39 CYP51A mutant Aspergillus fumigatus strains. The strip full inhibition endpoint (FIE) and 80% growth inhibition endpoint were determined by two independent readers, reader 1 (R1) and R2. The essent......We evaluated the MIC Strip Isavuconazole test against EUCAST E.Def 9.3 by using 40 wild-type and 39 CYP51A mutant Aspergillus fumigatus strains. The strip full inhibition endpoint (FIE) and 80% growth inhibition endpoint were determined by two independent readers, reader 1 (R1) and R2...

  4. Genomic analysis of the aconidial and high-performance protein producer, industrially relevant Aspergillus niger SH2 strain.

    Science.gov (United States)

    Yin, Chao; Wang, Bin; He, Pan; Lin, Ying; Pan, Li

    2014-05-15

    Aspergillus niger is usually regarded as a beneficial species widely used in biotechnological industry. Obtaining the genome sequence of the widely used aconidial A. niger SH2 strain is of great importance to understand its unusual production capability. In this study we assembled a high-quality genome sequence of A. niger SH2 with approximately 11,517 ORFs. Relatively high proportion of genes enriched for protein expression related FunCat items verify its efficient capacity in protein production. Furthermore, genome-wide comparative analysis between A. niger SH2 and CBS513.88 reveals insights into unique properties of A. niger SH2. A. niger SH2 lacks the gene related with the initiation of asexual sporulation (PrpA), leading to its distinct aconidial phenotype. Frame shift mutations and non-synonymous SNPs in genes of cell wall integrity signaling, β-1,3-glucan synthesis and chitin synthesis influence its cell wall development which is important for its hyphal fragmentation during industrial high-efficiency protein production. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Aggregation of endosomal-vacuolar compartments in the Aovps24-deleted strain in the filamentous fungus Aspergillus oryzae

    International Nuclear Information System (INIS)

    Tatsumi, Akinori; Shoji, Jun-ya; Kikuma, Takashi; Arioka, Manabu; Kitamoto, Katsuhiko

    2007-01-01

    Previously, we found that deletion of Aovps24, an ortholog of Saccharomyces cerevisiae VPS24, that encodes an ESCRT (endosomal sorting complex required for transport)-III component required for late endosomal function results in fragmented and aggregated vacuoles. Although defective late endosomal function is likely responsible for this phenotype, critical lack of our knowledge on late endosomes in filamentous fungi prevented us from further characterization. In this study, we identified late endosomes of Aspergillus oryzae, by expressing a series of fusion proteins of fluorescent proteins with orthologs of late endosomal proteins. Using these fusion proteins as markers, we observed late endosomes in the wild type strain and the Aovps24 disruptant and demonstrated that late endosomes are aberrantly aggregated in the Aovps24 disruptant. Moreover, we revealed that the aggregated late endosomes have features of vacuoles as well. As deletion of another ESCRT-III component-encoding gene, Aovps2, resulted in similar phenotypes to that in the Aovps24 disruptant, phenotypes of the Aovps24 disruptant are probably due to defective late endosomal function

  6. Aspergillus fumigatus and Related Species

    Science.gov (United States)

    Sugui, Janyce A.; Kwon-Chung, Kyung J.; Juvvadi, Praveen R.; Latgé, Jean-Paul; Steinbach, William J.

    2015-01-01

    The genus Aspergillus contains etiologic agents of aspergillosis. The clinical manifestations of the disease range from allergic reaction to invasive pulmonary infection. Among the pathogenic aspergilli, Aspergillus fumigatus is most ubiquitous in the environment and is the major cause of the disease, followed by Aspergillus flavus, Aspergillus niger, Aspergillus terreus, Aspergillus nidulans, and several species in the section Fumigati that morphologically resemble A. fumigatus. Patients that are at risk for acquiring aspergillosis are those with an altered immune system. Early diagnosis, species identification, and adequate antifungal therapy are key elements for treatment of the disease, especially in cases of pulmonary invasive aspergillosis that often advance very rapidly. Incorporating knowledge of the basic biology of Aspergillus species to that of the diseases that they cause is fundamental for further progress in the field. PMID:25377144

  7. Aspergillus fumigatus-Related Species in Clinical Practice

    Directory of Open Access Journals (Sweden)

    Frederic eLamoth

    2016-05-01

    Full Text Available Aspergillus fumigatus is the main etiologic agent of invasive aspergillosis (IA. Other Aspergillus species belonging to the section Fumigati (A. fumigatus complex may occasionally be the cause of IA. These strains are often misidentified, as they cannot be distinguished from A. fumigatus by conventional morphological analysis and sequencing methods. This lack of recognition may have important consequences as these A. fumigatus-related species often display some level of intrinsic resistance to azoles and other antifungal drugs. A. lentulus, A. udagawae, A. viridinutans and A. thermomutatus (Neosartorya pseudofischeri have been associated with refractory cases of IA. Microbiologists should be able to suspect the presence of these cryptic species behind a putative A. fumigatus isolate on the basis of some simple characteristics, such as defect in sporulation and/or unusual antifungal susceptibility profile. However, definitive species identification requires specific sequencing analyses of the beta-tubulin or calmodulin genes, which are not available in most laboratories. Multiplex PCR assays or matrix-assisted laser desorption ionization – time-of-flight mass spectrometry (MALDI-TOF MS gave promising results for rapid and accurate distinction between A. fumigatus and other Aspergillus spp. of the section Fumigati in clinical practice. Improved diagnostic procedures and antifungal susceptibility testing may be helpful for the early detection and management of these particular IA cases.

  8. Combined molecular and biochemical approach identifies Aspergillus japonicus and Aspergillus aculeatus as two species

    DEFF Research Database (Denmark)

    Parenicova, L.; Skouboe, P.; Frisvad, Jens Christian

    2001-01-01

    of the internal transcribed spacers (ITS1 and ITS2) and the 5.8S rRNA gene could not be used to distinguish between A. japonicus and A. aculeatus but did show that these two taxa are more closely related to each other than to other species of black aspergilli. Aspergillus niger pyruvate kinase (pkiA) and pectin...... variation when they were probed with the pelA gene. The secondary-metabolite profiles supported division of the isolates into the two species and differed from those of other black aspergilli. The strains classified as A. japonicus produced indole alkaloids and a polar metabolite, while the A. aculeatus...... lyase A (pelA) and Agaricus bisporus 28S rRNA genes, which were used as probes in the RFLP analysis, revealed clear polymorphism between these two taxa. The A. niger pkiA and pelA probes placed six strains in an A. japonicus group and 12 isolates in an A. aculeatus group, which exhibited intraspecific...

  9. Biodiversity of Aspergillus species in some important agricultural products.

    Science.gov (United States)

    Perrone, G; Susca, A; Cozzi, G; Ehrlich, K; Varga, J; Frisvad, J C; Meijer, M; Noonim, P; Mahakarnchanakul, W; Samson, R A

    2007-01-01

    The genus Aspergillus is one of the most important filamentous fungal genera. Aspergillus species are used in the fermentation industry, but they are also responsible of various plant and food secondary rot, with the consequence of possible accumulation of mycotoxins. The aflatoxin producing A. flavus and A. parasiticus, and ochratoxinogenic A. niger, A. ochraceus and A. carbonarius species are frequently encountered in agricultural products. Studies on the biodiversity of toxigenic Aspergillus species is useful to clarify molecular, ecological and biochemical characteristics of the different species in relation to their different adaptation to environmental and geographical conditions, and to their potential toxigenicity. Here we analyzed the biodiversity of ochratoxin producing species occurring on two important crops: grapes and coffee, and the genetic diversity of A. flavus populations occurring in agricultural fields. Altogether nine different black Aspergillus species can be found on grapes which are often difficult to identify with classical methods. The polyphasic approach used in our studies led to the identification of three new species occurring on grapes: A. brasiliensis, A. ibericus, and A. uvarum. Similar studies on the Aspergillus species occurring on coffee beans have evidenced in the last five years that A. carbonarius is an important source of ochratoxin A in coffee. Four new species within the black aspergilli were also identified in coffee beans: A. sclerotioniger, A. lacticoffeatus, A. sclerotiicarbonarius, and A. aculeatinus. The genetic diversity within A. flavus populations has been widely studied in relation to their potential aflatoxigenicity and morphological variants L- and S-strains. Within A. flavus and other Aspergillus species capable of aflatoxin production, considerable diversity is found. We summarise the main recent achievements in the diversity of the aflatoxin gene cluster in A. flavus populations, A. parasiticus and the non

  10. Aspergillus section Flavi community structure in Zambia influences aflatoxin contamination of maize and groundnut.

    Science.gov (United States)

    Kachapulula, Paul W; Akello, Juliet; Bandyopadhyay, Ranajit; Cotty, Peter J

    2017-11-16

    Aflatoxins are cancer-causing, immuno-suppressive mycotoxins that frequently contaminate important staples in Zambia including maize and groundnut. Several species within Aspergillus section Flavi have been implicated as causal agents of aflatoxin contamination in Africa. However, Aspergillus populations associated with aflatoxin contamination in Zambia have not been adequately detailed. Most of Zambia's arable land is non-cultivated and Aspergillus communities in crops may originate in non-cultivated soil. However, relationships between Aspergillus populations on crops and those resident in non-cultivated soils have not been explored. Because characterization of similar fungal populations outside of Zambia have resulted in strategies to prevent aflatoxins, the current study sought to improve understanding of fungal communities in cultivated and non-cultivated soils and in crops. Crops (n=412) and soils from cultivated (n=160) and non-cultivated land (n=60) were assayed for Aspergillus section Flavi from 2012 to 2016. The L-strain morphotype of Aspergillus flavus and A. parasiticus were dominant on maize and groundnut (60% and 42% of Aspergillus section Flavi, respectively). Incidences of A. flavus L-morphotype were negatively correlated with aflatoxin in groundnut (log y=2.4990935-0.09966x, R 2 =0.79, P=0.001) but not in maize. Incidences of A. parasiticus partially explained groundnut aflatoxin concentrations in all agroecologies and maize aflatoxin in agroecology III (log y=0.1956034+0.510379x, R 2 =0.57, Pagroecologies across Zambia gives support for modifying fungal community structure to reduce the aflatoxin-producing potential. Published by Elsevier B.V.

  11. What can comparative genomics tell us about species concepts in the genus Aspergillus?

    Energy Technology Data Exchange (ETDEWEB)

    Rokas, Antonis; payne, gary; Federova, Natalie D.; Baker, Scott E.; Machida, Masa; yu, Jiujiang; georgianna, D. R.; Dean, Ralph A.; Bhatnagar, Deepak; Cleveland, T. E.; Wortman, Jennifer R.; Maiti, R.; Joardar, V.; Amedeo, Paolo; Denning, David W.; Nierman, William C.

    2007-12-15

    Understanding the nature of species" boundaries is a fundamental question in evolutionary biology. The availability of genomes from several species of the genus Aspergillus allows us for the first time to examine the demarcation of fungal species at the whole-genome level. Here, we examine four case studies, two of which involve intraspecific comparisons, whereas the other two deal with interspecific genomic comparisons between closely related species. These four comparisons reveal significant variation in the nature of species boundaries across Aspergillus. For example, comparisons between A. fumigatus and Neosartorya fischeri (the teleomorph of A. fischerianus) and between A. oryzae and A. flavus suggest that measures of sequence similarity and species-specific genes are significantly higher for the A. fumigatus - N. fischeri pair. Importantly, the values obtained from the comparison between A. oryzae and A. flavus are remarkably similar to those obtained from an intra-specific comparison of A. fumigatus strains, giving support to the proposal that A. oryzae represents a distinct ecotype of A. flavus and not a distinct species. We argue that genomic data can aid Aspergillus taxonomy by serving as a source of novel and unprecedented amounts of comparative data, as a resource for the development of additional diagnostic tools, and finally as a knowledge database about the biological differences between strains and species.

  12. Effects of sugar and amino acid supplementation on Aureobasidium pullulans NRRL 58536 antifungal activity against four Aspergillus species.

    Science.gov (United States)

    Prasongsuk, Sehanat; Ployngam, Saowaluck; Wacharasindhu, Sumrit; Lotrakul, Pongtharin; Punnapayak, Hunsa

    2013-09-01

    Cultured cell extracts from ten tropical strains of Aureobasidium pullulans were screened for antifungal activity against four pathogenic Aspergillus species (Aspergillus flavus, Aspergillus niger, Aspergillus fumigatus, and Aspergillus terreus) using the well diffusion and conidial germination inhibition assays. The crude cell extract from A. pullulans NRRL 58536 resulted in the greatest fungicidal activity against all four Aspergillus species and so was selected for further investigation into enhancing the production of antifungal activity through optimization of the culture medium, carbon source (sucrose and glucose) and amino acid (phenylalanine, proline, and leucine) supplementation. Sucrose did not support the production of any detectable antifungal activity, while glucose did with the greatest antifungal activity against all four Aspergillus species being produced in cells grown in medium containing 2.5 % (w/v) glucose. With respect to the amino acid supplements, variable trends between the different Aspergillus species and amino acid combinations were observed, with the greatest antifungal activities being obtained when grown with phenylalanine plus leucine supplementation for activity against A. flavus, proline plus leucine for A. terreus, and phenylalanine plus proline and leucine for A. niger and A. fumigatus. Thin layer chromatography, spectrophotometry, high-performance liquid chromatography, (1)H-nuclear magnetic resonance, and MALDI-TOF mass spectrometry analyses were all consistent with the main component of the A. pullulans NRRL 58536 extracts being aureobasidins.

  13. Comparative proteome analysis of Aspergillus oryzae 3.042 and A. oryzae 100-8 strains: Towards the production of different soy sauce flavors.

    Science.gov (United States)

    Zhao, Guozhong; Hou, Lihua; Yao, Yunping; Wang, Chunling; Cao, Xiaohong

    2012-07-16

    Aspergillus oryzae plays a central role in soybean fermentation, particularly in its contribution to the flavor of soy sauce. We present a comparative assessment of the intracellular differences between wild-type strain 3.042 and mutant strain A100-8, at the proteome level. 522 different protein spots were identified by MALDI-TOF MS, with 134 spots being confirmed by MALDI-TOF MS/MS. Of these, 451 were differentially expressed proteins (DEPs). There was at least a two-fold increase for 288 spots, and at least a two-fold decrease for 163 spots, in strain A100-8 when compared to 3.042. Further analysis showed that 63 of the more abundant proteins were involved in glycolysis and the citrate cycle; 43 more abundant proteins and 10 less abundant proteins were related to amino acid biosynthesis and metabolism; two of the more abundant proteins were involved in vitamin biosynthesis; and five of the more abundant proteins and four of the less abundant proteins were related to secondary metabolites. Moreover, quantitative real time PCR showed that the mRNA expression levels of six typical genes we selected were consistent with changes in protein expression. We postulate that there may be a relationship between DEPs and the flavor formation mechanism in A. oryzae. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

  14. Conventional Morphology Versus PCR Sequencing, rep-PCR, and MALDI-TOF-MS for Identification of Clinical Aspergillus Isolates Collected Over a 2-Year Period in a University Hospital at Kayseri, Turkey.

    Science.gov (United States)

    Atalay, Altay; Koc, Ayse Nedret; Suel, Ahmet; Sav, Hafize; Demir, Gonca; Elmali, Ferhan; Cakir, Nuri; Seyedmousavi, Seyedmojtaba

    2016-09-01

    Aspergillus species cause a wide range of diseases in humans, including allergies, localized infections, or fatal disseminated diseases. Rapid detection and identification of Aspergillus spp. facilitate effective patient management. In the current study we compared conventional morphological methods with PCR sequencing, rep-PCR, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) for the identification of Aspergillus strains. A total of 24 consecutive clinical isolates of Aspergillus were collected during 2012-2014. Conventional morphology and rep-PCR were performed in our Mycology Laboratory. The identification, evaluation, and reporting of strains using MALDI-TOF-MS were performed by BioMérieux Diagnostic, Inc. in Istanbul. DNA sequence analysis of the clinical isolates was performed by the BMLabosis laboratory in Ankara. Samples consisted of 18 (75%) lower respiratory tract specimens, 3 otomycosis (12.5%) ear tissues, 1 sample from keratitis, and 1 sample from a cutaneous wound. According to DNA sequence analysis, 12 (50%) specimens were identified as A. fumigatus, 8 (33.3%) as A. flavus, 3 (12.5%) as A. niger, and 1 (4.2%) as A. terreus. Statistically, there was good agreement between the conventional morphology and rep-PCR and MALDI-TOF methods; kappa values were κ = 0.869, 0.871, and 0.916, respectively (P < 0.001). The good level of agreement between the methods included in the present study and sequence method could be due to the identification of Aspergillus strains that were commonly encountered. Therefore, it was concluded that studies conducted with a higher number of isolates, which include other Aspergillus strains, are required. © 2016 Wiley Periodicals, Inc.

  15. Isolation and characterization of a native strain of Aspergillus niger ZRS14 with capability of high resistance to zinc and its supernatant application towards extracellular synthesis of zinc oxide nanoparticles

    Directory of Open Access Journals (Sweden)

    Morahem Ashengroph

    2013-01-01

    Full Text Available Introduction: Zinc oxide nanoparticles have quite a few applications in the fields of biology, optics, mechanics, magnetism, energy, hygiene and medicine. Due to serious problems associated with physiochemical synthesis of ZnO nanoparticles, including environmental pollution, complicated and costly processes, there is a growing need to develop a simple biological procedure for synthesis of nanoparticles to achieve the monodisperse-sized particles with a higher purity, low energy consumption and a cleaner environment. We conducted this investigation to screen and isolate native fungi strains capable of high zinc metal tolerance ability and a potential for extracellular synthesis of ZnO nanoparticles using fungal secretions as biological catalysts.Materials and methods: 15 different strains of fungi were isolated from soil samples collected from lead and zinc mines of Angoran-Zanjan using conventional enrichment process and characterized initially based on macroscopic and microscopic characteristics and colony morphology. The intrinsic tolerance of the isolated strains to zinc toxic metal was measured in the synthetic and complex media using the agar dilution method. The supernatants of isolated fungi were incubated with zinc acetate solution in a shaker incubator for 72h; then, the strain that was able to synthesis ZnO nanoparticle was identified. The ZnO nanoparticles formation was investigated by using spectroscopic techniques and microscopic observations.Results: Among the 15 isolated strains, the strain ZRS14 had highest zinc metal tolerance ability and was selected and identified as Aspergillus niger strain ZRS14 (GenBank accession number KF414527 based on morphological and molecular phylogenetic analysis. For synthesis of ZnO nanoparticles by isolated A. niger ZRS14, fungal cell-free filtrate of the strain was collected and incubated in the presence of zinc acetate solution at a final concentration of 250 mg/l zinc metal ion at 28º C for

  16. Isolation, Optimization, and Investigation of Production of Linoleic Acid in Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Noushin Shafiei

    2016-08-01

    Full Text Available Background and Objectives: Microorganisms that are capable of accumulating lipid up to 20% of their biomass are called oleaginous microorganisms. In this study, optimization in lipid and linolenic acid production was investigated in Aspergillus niger as an oleaginous filamentous fungi. Methods: In this study, at first different strains of filamentous fungi were isolated, and after staining of the isolates with Sudan Black, their oil was extracted using chloroform/methanol. Then, the isolates with oil/dry biomass ratio of more than 20% were considered as oleaginous filamentous fungi. After microscopic examination, the identified isolate was optimized in terms of oil production. Finally, the amount of linolenic acid was evaluated using gas chromatography. Results: At first, 20 filamentous fungi isolates were isolated. According to the results of Sudan Black staining, lipid inclusions were observed in all the fungal isolates. The amount of oil produced in all isolates, showed that the percentage of oil production in isolates 4, 5, and 16, was more than 20%. In microscopic examination, the isolate 5 was Aspergillus niger. The best pH, temperature, time, and carbon source for oil production by Aspergillus niger was 4.5, 30°C, 96 hours, and fructose, respectively. The amount of linolenic acid in Aspergillus niger was reported 22.4% using gas chromatography.   Conclusion: The results of this study revealed that Aspergillus niger is an appropriate filamentous fungi for linolenic acid production.   

  17. Improvement of selected strains through gamma irradiation for enhanced lipolytic potential

    International Nuclear Information System (INIS)

    Iftikhar, T.; Mubashir, N.; Hussain, Y.; Abbas, S.Q.; Ashraf, I.

    2010-01-01

    The purpose of the present investigation was to enhance the production of industrially important enzyme lipase by subjecting the wild lipase producing fungal strains i.e. Aspergillus niger, Rhizopus microsporus and Penicillium atrovenetum to various doses of gamma irradiation (20, 40, 60, 80, 100, 120, 140 and 160 Gy). The isolation and lipolytic activity of selected mutant derived strains is described in this paper. Among all the mutants tested, MBL-5 obtained at 140Gy of Aspergillus niger strain showed highest extracellular lipase activity (13.75 +- 0.15 U mL/sup -1/) while MBL-1 Rhizopus microsporus at the rate 20Gy showed the lowest activity i.e., 1.06 +- 0.11 U mL/sup -1/. A range of pH 3, 5, 7, 9 and 11 was used to check the lipolytic potential of various mutants along with their wild type. It was observed that MBL-5 (Aspergillus niger) and MBL-2 (Rhizopus microsporus) showed enhanced extracellular lipase activity at pH 11 while MBL-3 (Penicillium atrovenetum) showed the highest extracellular lipase activity 22.53 +- 0.21 U mL/sup -1/ at pH 9. It indicates a possible role for the MBL-2, MBL-3 and MBL-5 mutant strains in the detergent industry for the development of eco-friendly technologies. (author)

  18. The isolation and improvement of Aspergillus niger by radiation for higher production of citric acid

    International Nuclear Information System (INIS)

    Radziah A; Foziah Ali; Zainab H

    2000-01-01

    Local citric acid producer of fungal strain Aspergillus niger have been successfully isolated from stale bread and onion. The isolates, designated as SB 1 and NN I showed a potential performance for citric acid production of 49% and 52% yield respectively, in shake flask studies. The strain improvement on NN1 was carried out by radiation induced mutation by gamma rays at LD 5 0 of 1.28 kGy

  19. Induction of mutation in Aspergillus niger for conversion of cellulose into glucose

    Energy Technology Data Exchange (ETDEWEB)

    Helmi, S.; Khalil, A.E.; Tahoun, M.K.; Khairy, A.H. [Univ. of Alexandria Research Centre, Alexandria (Egypt)

    1991-12-31

    Plant wastes are very important part of biomass used and investigated for energy, chemical, and fuel production. Cellulose is the major renewable form of carbohydrate in the world, about 10{sup 11} tons of which is synthesized annually. For general use, it must be hydrolyzed first, either chemically or by cellulases derived from a few specialized microorganisms. Enzymes are acceptable environmentally but expensive to produce. Certainly, induction of mutations and selection of high cellulose microbial strains with significant adaptability to degrade cellulose to glucose is promising solutions. Induction of mutations in other fungi and Aspergillus sp. rather than Aspergillus niger was reported. Aspergillus ustus and Trichoderma harzianum were induced by gamma irradiation indicating mutants that excrete higher cellulose yields, particularly exocellobiohydrolase (Avicelase) than their respective wild types. Mutants from the celluiolytic fungus Penicillium pinophilum were induced by chemical and UV-irradiation. Enhancing the production of endo-1,4-{Beta}-D-glucanase (CMCase) and particularly {Beta}-glucosidase was obtained by gamma irradiation of Altemaria alternate. To overcome the lower activity of {beta}-glucosidase in certain fungi species rather than A. niger, mixed cultures of different species were tried. Thus, Aspergillus phonicis with Trichoderma reesei Rut 30, produced a cellulose complex that improved activity twofold over cellulose from Trichoderma alone.

  20. Effect of deletion of chitin synthase genes on mycelial morphology and culture viscosity in Aspergillus oryzae

    DEFF Research Database (Denmark)

    Müller, Christian; Hansen, K.; Szabo, Peter

    2003-01-01

    The objective of this study was to quantify the effect of disrupting two chitin synthases, chsB and csmA, on the morphology and rheology during batch cultivation of Aspergillus oryzae. The rheological properties were characterized in batch cultivations at different biomass concentrations (from 3...... broth was significantly affected by the biomass concentration, the morphology, and also by pH. The chsB disruption strain had lower consistency index K values for all biomass concentrations investigated, which is a desirable trait for industrial Aspergillus fermentations. (C) 2003 Wiley Periodicals, Inc....

  1. Optimisation of nutritional requirements for dopamine synthesis by calcium alginate-entrapped mutant strain of Aspergillus oryzae EMS-6.

    Science.gov (United States)

    Ali, Sikander; Nawaz, Wajeeha

    2017-02-01

    The optimisation of nutritional requirements for dopamine (DA) synthesis by calcium alginate-entrapped mutant variant of Aspergillus oryzae EMS-6 using submerged fermentation technique was investigated. A total of 13 strains were isolated from soil. Isolate I-2 was selected as a better producer of DA and improved by exposing with ethyl methylsulphonate (EMS). EMS-6 was selected as it exhibited 43 μg/mL DA activity. The mutant variable was further treated with low levels of l-cysteine HCl to make it resistant against diversion and environmental stress. The conidiospores of mutant variant were entrapped in calcium alginate beads for stable product formation. EMS-6 gave maximum DA activity (124 μg/mL) when supplemented with 0.1% peptone and 0.2% sucrose, under optimised parameters viz. pH 3, temperature of 55 °C and incubation time of 70 min. The study involves the high profile of DA activity and is needed, as DA is capable to control numerous neurogenic disorders.

  2. Mitotic catastrophe is the mechanism of lethality for mutations that confer mutagen sensitivity in Aspergillus nidulans.

    Science.gov (United States)

    Denison, S H; May, G S

    1994-01-16

    We have examined the consequences of treatment with DNA-damaging agents of uvs mutants and the bimD6 mutant of Aspergillus nidulans. We first established that wild-type Aspergillus undergoes a cell cycle delay following treatment with the DNA-damaging agents methyl methanesulfonate (MMS) or ultraviolet light (UV). We have also determined that strains carrying the bimD6, uvsB110, uvsH77, uvsF201 and the uvsC114 mutations, all of which cause an increased sensitivity to DNA-damaging agents, undergo a cell-cycle delay following DNA damage. These mutations therefore do not represent nonfunctional checkpoints in Aspergillus. However, all of the mutant strains accumulated nuclear defects after a period of delay following mutagen treatment. The nuclear defects in the uvsB110 and bimD6 strains following MMS treatment were shown to be dependent on passage through mitosis after DNA damage, as the defects were prevented with benomyl. Checkpoint controls responding to DNA damage thus only temporarily halt cell-cycle progression in response to DNA damage. The conditional bimD6 mutation also results in a defective mitosis at restrictive temperatures. This mitotic defect is similar to that seen with MMS treatment at temperatures permissive for the mitotic defect. Thus the bimD gene product may perform dual roles, one in DNA repair and the other during the mitotic cell cycle in the absence of damage.

  3. Genetic analysis of DNA repair in Aspergillus: evidence for different types of MMS-sensitive hyperrec mutants

    International Nuclear Information System (INIS)

    Kaefer, E.; Mayor, O.

    1986-01-01

    To identify genes which affect DNA repair and possibly recombination in Aspergillus nidulans, mutants hypersensitive to methyl methanesulphonate (MMS) were induced with ultraviolet light (UV) or γ-rays. To identify functional and epistatic groups, mutants from each uvs gene were tested for effects on recombination and mutation, and double mutant uvs strains were compared for UV survival to their component single mutant strains. (Auth.)

  4. High sequence variations in the region containing genes encoding a cellular morphogenesis protein and the repressor of sexual development help to reveal origins of Aspergillus oryzae

    Science.gov (United States)

    Aspergillus oryzae and Aspergillus flavus are closely related fungal species. The A. flavus population that produces numerous small sclerotia (S strain) and aflatoxin has a unique 1.5 kb deletion in the norB-cypA region of the aflatoxin gene cluster (the S genotype). Phylogenetic studies have indica...

  5. Aspergillus oryzae nrtA affects kojic acid production.

    Science.gov (United States)

    Sano, Motoaki

    2016-09-01

    We analyzed the role of the nitrate transporter-encoding gene (nrtA) of Aspergillus oryzae by gene disruption. Southern hybridization analysis indicated that homologous recombination occurred at the resident nrtA locus. Real-time PCR showed that the nrtA gene was strongly inducible by NaNO3. The nrtA disruptant did not exhibit normal growth when nitrate was available as the sole nitrogen source. These results indicate that NrtA is essential for nitrate uptake in A. oryzae. Kojic acid (KA) production was inhibited by the addition of a small amount of sodium nitrate. The nrtA-disrupted strain was deficient in the uptake of nitrate. As a result, KA production in this strain was not considerably affected by the presence of nitrate.

  6. Analysis on the DNA Fingerprinting of Aspergillus Oryzae Mutant Induced by High Hydrostatic Pressure

    International Nuclear Information System (INIS)

    Wang Hua; Zhang Jian; Wang Kai; Liu Bing-Bing; Zou Bo; Zou Guang-Tian; Yang Fan; Shen Si-Le

    2011-01-01

    The mutant strains of aspergillus oryzae (HP300a) are screened under 300 MPa for 20 min. Compared with the control strains, the screened mutant strains have unique properties such as genetic stability, rapid growth, lots of spores, and high protease activity. Random amplified polymorphic DNA (RAPD) and inter simple sequence repeats (ISSR) are used to analyze the DNA fingerprinting of HP300a and the control strains. There are 67.9% and 51.3% polymorphic bands obtained by these two markers, respectively, indicating significant genetic variations between HP300a and the control strains. In addition, comparison of HP300a and the control strains, the genetic distances of random sequence and simple sequence repeat of DNA are 0.51 and 0.34, respectively. (general)

  7. Analysis on the DNA Fingerprinting of Aspergillus Oryzae Mutant Induced by High Hydrostatic Pressure

    Science.gov (United States)

    Wang, Hua; Zhang, Jian; Yang, Fan; Wang, Kai; Shen, Si-Le; Liu, Bing-Bing; Zou, Bo; Zou, Guang-Tian

    2011-01-01

    The mutant strains of aspergillus oryzae (HP300a) are screened under 300 MPa for 20 min. Compared with the control strains, the screened mutant strains have unique properties such as genetic stability, rapid growth, lots of spores, and high protease activity. Random amplified polymorphic DNA (RAPD) and inter simple sequence repeats (ISSR) are used to analyze the DNA fingerprinting of HP300a and the control strains. There are 67.9% and 51.3% polymorphic bands obtained by these two markers, respectively, indicating significant genetic variations between HP300a and the control strains. In addition, comparison of HP300a and the control strains, the genetic distances of random sequence and simple sequence repeat of DNA are 0.51 and 0.34, respectively.

  8. Enhanced production of fructosyltransferase in Aspergillus oryzae by genome shuffling.

    Science.gov (United States)

    Wang, Shenghai; Duan, Mengjie; Liu, Yalan; Fan, Sen; Lin, Xiaoshan; Zhang, Yi

    2017-03-01

    To breed Aspergillus oryzae strains with high fructosyltransferase (FTase) activity using intraspecific protoplast fusion via genome-shuffling. A candidate library was developed using UV/LiCl of the conidia of A. oryzae SBB201. By screening for enzyme activity and cell biomass, two mutants (UV-11 and UV-76) were chosen for protoplast fusion and subsequent genome shuffling. After three rounds of genome recombination, a fusion mutant RIII-7 was obtained. Its FTase activity was 180 U g -1 , approximately double that of the original strain, and RIII-7 was genetically stable. In fermentation culture, FTase activity of the genome-shuffled strain reached a maximum of 353 U g -1 using substrate-feeding method, and this value was approximately 3.4-times higher than that of the original strain A. oryzae SBB201. Intraspecific protoplast fusion of A. oryzae significantly enhanced FTase activity and generated a potentially useful strain for industrial production.

  9. Quantifying the importance of galactofuranose in Aspergillus nidulans hyphal wall surface organization by atomic force microscopy.

    Science.gov (United States)

    Paul, Biplab C; El-Ganiny, Amira M; Abbas, Mariam; Kaminskyj, Susan G W; Dahms, Tanya E S

    2011-05-01

    The fungal wall mediates cell-environment interactions. Galactofuranose (Galf), the five-member ring form of galactose, has a relatively low abundance in Aspergillus walls yet is important for fungal growth and fitness. Aspergillus nidulans strains deleted for Galf biosynthesis enzymes UgeA (UDP-glucose-4-epimerase) and UgmA (UDP-galactopyranose mutase) lacked immunolocalizable Galf, had growth and sporulation defects, and had abnormal wall architecture. We used atomic force microscopy and force spectroscopy to image and quantify cell wall viscoelasticity and surface adhesion of ugeAΔ and ugmAΔ strains. We compared the results for ugeAΔ and ugmAΔ strains with the results for a wild-type strain (AAE1) and the ugeB deletion strain, which has wild-type growth and sporulation. Our results suggest that UgeA and UgmA are important for cell wall surface subunit organization and wall viscoelasticity. The ugeAΔ and ugmAΔ strains had significantly larger surface subunits and lower cell wall viscoelastic moduli than those of AAE1 or ugeBΔ hyphae. Double deletion strains (ugeAΔ ugeBΔ and ugeAΔ ugmAΔ) had more-disorganized surface subunits than single deletion strains. Changes in wall surface structure correlated with changes in its viscoelastic modulus for both fixed and living hyphae. Wild-type walls had the largest viscoelastic modulus, while the walls of the double deletion strains had the smallest. The ugmAΔ strain and particularly the ugeAΔ ugmAΔ double deletion strain were more adhesive to hydrophilic surfaces than the wild type, consistent with changes in wall viscoelasticity and surface organization. We propose that Galf is necessary for full maturation of A. nidulans walls during hyphal extension.

  10. Antifungal activity of strains of lactic acid bacteria isolated from a semolina ecosystem against Penicillium roqueforti, Aspergillus niger and Endomyces fibuliger contaminating bakery products.

    Science.gov (United States)

    Valerio, Francesca; Favilla, Mara; De Bellis, Palmira; Sisto, Angelo; de Candia, Silvia; Lavermicocca, Paola

    2009-09-01

    Thirty samples of Italian durum wheat semolina and whole durum wheat semolina, generally used for the production of Southern Italy's traditional breads, were subjected to microbiological analysis in order to explore their lactic acid bacteria (LAB) diversity and to find strains with antifungal activity. A total of 125 presumptive LAB isolates (Gram-positive and catalase-negative) were characterized by repetitive extragenic palindromic-PCR (REP-PCR) and sequence analysis of the 16S rRNA gene, leading to the identification of the following species: Weissella confusa, Weissella cibaria, Leuconostoc citreum, Leuconostoc mesenteroides, Lactococcus lactis, Lactobacillus rossiae and Lactobacillus plantarum. The REP-PCR results delineated 17 different patterns whose cluster analysis clearly differentiated W. cibaria from W. confusa isolates. Seventeen strains, each characterized by a different REP-PCR pattern, were screened for their antifungal properties. They were grown in a flour-based medium, comparable to a real food system, and the resulting fermentation products (FPs) were tested against fungal species generally contaminating bakery products, Aspergillus niger, Penicillium roqueforti and Endomyces fibuliger. The results of the study indicated a strong inhibitory activity - comparable to that obtained with the common preservative calcium propionate (0.3% w/v) - of ten LAB strains against the most widespread contaminant of bakery products, P. roqueforti. The screening also highlighted the unexplored antifungal activity of L. citreum, L. rossiae and W. cibaria (1 strain), which inhibited all fungal strains to the same or a higher extent compared with calcium propionate. The fermentation products of these three strains were characterized by low pH values, and a high content of lactic and acetic acids.

  11. Pre-termination in aflR of Aspergillus sojae inhibits aflatoxin biosynthesis.

    Science.gov (United States)

    Matsushima, K; Chang, P K; Yu, J; Abe, K; Bhatnagar, D; Cleveland, T E

    2001-05-01

    The aflR gene product is the main transcriptional regulator of aflatoxin biosynthesis in Aspergillus parasiticus and Aspergillus flavus. Although A. sojae strains do not produce aflatoxins, they do have an aflR homologue. When compared with the aflR of A. parasiticus, the A. sojae gene contains two mutations: an HAHA motif and a premature stop codon. To investigate the functionality of the A. sojae aflR gene product, we used a GAL4 one-hybrid system in yeast. The transcription-activating activity of AflR from A. sojae was 15% of that from A. parasiticus. The introduction of an additional aflR from A. sojae into an A. parasiticus strain did not affect aflatoxin productivity. A hybrid aflR comprising the amino-terminal region of A. sojae aflR and the carboxy-terminal region of A. parasiticus aflR suppressed the effect associated with pre-termination of the A. sojae AflR. We conclude that the premature stop codon of the A. sojae aflR is the key to its functionality and leads to prevention of aflatoxin biosynthesis through loss of the transcription of aflatoxin biosynthesis-related genes.

  12. Influence of nitrogen sources on amino acid production by aspergillus niger

    International Nuclear Information System (INIS)

    Almani, F.; Dahot, M.U.

    2007-01-01

    The effect of different organic and inorganic nitrogen sources in 0.1% and 0.2% concentration on the production of amino acid was studied using a wild strain of Aspergillus niger. The rate of amino acid biosynthesis was found to be higher when 0.2% corn steep liquor was incorporated in the mineral medium. It was concluded from the study that the amino acid synthesis by wild strain depends not only on the nature and type of nitrogen sources used but the concentration of nitrogen source also play an important in the accumulation of free amino acids in the medium. (author)

  13. Aspergillus uvarum sp. nov., an uniseriate black Aspergillus species isolated from grapes in Europe

    DEFF Research Database (Denmark)

    Perrone, Giancarlo; Varga, János; Susca, Antonia

    2008-01-01

    uvarum sp. nov. isolates produced secalonic acid, common to other Aspergillus japonicus-related taxa, and geodin, erdin and dihydrogeodin, which are not produced by any other black aspergilli. None of the isolates were found to produce ochratoxin A. The novel species is most closely related to two......A novel species, Aspergillus uvarum sp. nov., is described within Aspergillus section Nigri. This species can be distinguished from other black aspergilli based on internal transcribed spacers (ITS), beta-tubulin and calmodulin gene sequences, by AFLP analysis and by extrolite profiles. Aspergillus...

  14. Aspergillus--classification and antifungal susceptibilities.

    Science.gov (United States)

    Buzina, Walter

    2013-01-01

    Aspergillus is one of the most important fungal genera for the man, for its industrial use, its ability to spoil food and not least its medical impact as cause of a variety of diseases. Currently hundreds of species of Aspergillus are known; nearly fifty of them are able to cause infections in humans and animals. Recently, the genus Aspergillus is subdivided into 8 subgenera and 22 sections. The spectrum of diseases caused by Aspergillus species varies from superficial cutaneous to invasive and systemic infections. All species of Aspergillus investigated so far are resistant against the antifungals fluconazole and 5-fluorocytosine, the range of susceptibilities to currently available antifungals is discussed in this paper.

  15. Genome sequencing and analysis of the versatile cell factory Aspergillus niger CBS 513.88

    NARCIS (Netherlands)

    Pel, Herman J.; de Winde, Johannes H.; Archer, David B.; Dyer, Paul S.; Hofmann, Gerald; Schaap, Peter J.; Turner, Geoffrey; Albang, Richard; Albermann, Kaj; Andersen, Mikael R.; Bendtsen, Jannick D.; Benen, Jacques A. E.; van den Berg, Marco; Breestraat, Stefaan; Caddick, Mark X.; Contreras, Roland; Cornell, Michael; Coutinho, Pedro M.; Danchin, Etienne G. J.; Debets, Alfons J. M.; Dekker, Peter; van Dijck, Piet W. M.; van Dijk, Alard; Dijkhuizen, Lubbert; Driessen, Arnold J. M.; d'Enfert, Christophe; Geysens, Steven; Groot, Gert S. P.; de Groot, Piet W. J.; Guillemette, Thomas; Henrissat, Bernard; Herweijer, Marga; van den Hombergh, Johannes P. T. W.; van den Hondel, Cees A. M. J. J.; van der Heijden, Rene T. J. M.; van der Kaaij, Rachel M.; Klis, Frans M.; Kools, Harrie J.; Kubicek, Christian P.; van Kuyk, Patricia A.; Lauber, Juergen; Lu, Xin; van der Maarel, Marc J. E. C.; Meulenberg, Rogier; Menke, Hildegard; Mortimer, Martin A.; Nielsen, Jens; Oliver, Stephen G.; Olsthoorn, Maurien; Pal, Karoly; van Peij, Noel N. M. E.; Ram, Arthur F. J.; Rinas, Ursula; Roubos, Johannes A.; Sagt, Cees M. J.; Schmoll, Monika; Sun, Jibin; Ussery, David; Varga, Janos; Vervecken, Wouter; de Vondervoort, Peter J. J. van; Wedler, Holger; Wosten, Han A. B.; Zeng, An-Ping; van Ooyen, Albert J. J.; Visser, Jaap; Stam, Hein; Enfert, Christophe d’; Lauber, Jürgen; Goosen, Coenie; de Vries, Ronald P.

    The filamentous fungus Aspergillus niger is widely exploited by the fermentation industry for the production of enzymes and organic acids, particularly citric acid. We sequenced the 33.9-megabase genome of A. niger CBS 513.88, the ancestor of currently used enzyme production strains. A high level of

  16. HPLC Quantification of Cytotoxic Compounds from Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Paula Karina S. Uchoa

    2017-01-01

    Full Text Available A high-performance liquid chromatography method was developed and validated for the quantification of the cytotoxic compounds produced by a marine strain of Aspergillus niger. The fungus was grown in malt peptone dextrose (MPD, potato dextrose yeast (PDY, and mannitol peptone yeast (MnPY media during 7, 14, 21, and 28 days, and the natural products were identified by standard compounds. The validation parameters obtained were selectivity, linearity (coefficient of correlation > 0.99, precision (relative standard deviation below 5%, and accuracy (recovery > 96.

  17. Simultaneous amyloglucosidase and exo-polygalacturonase production by Aspergillus niger using solid-state fermentation

    Directory of Open Access Journals (Sweden)

    Jorge Alberto Vieira Costa

    2007-09-01

    Full Text Available Amyloglucosidase (AMG and exo-polygalacturonase (exo-PG were simultaneously produced by two different strains of Aspergillus niger in solid-state fermentation (SSF using defatted rice-bran as substrate. The effect of Aspergillus niger strain (t0005/007-2 and/or CCT 3312, inoculum type (spore suspension or fermented bran and addition of inducers (pectin and/or starch to the culture media was studied using a 3² x 2¹ factorial experimental design. The production of AMG and exo-PG was significantly affected by fungal strain and inoculum type but inducers had no effect. The maximum yields obtained were 1310 U/g dm for AMG using a spore suspension of A. niger CCT 3312 and 50.2 U/g dm for exo-PG production, using A. niger t0005/007-2 and fermented bran as inoculum. The yields obtained represented acceptable values in comparison with data available in the literature and indicated that defatted rice-bran was a good nutrient source.As enzimas amiloglicosidase (AMG e exo-poligalacturonase (exo-PG foram produzidas simultaneamente por duas cepas de Aspergillus niger, através de fermentação em estado sólido usando farelo de arroz desengordurado como substrato. Foram avaliados os efeitos da cepa de Aspergillus niger, tipo de inóculo e adição de indutores no meio de cultura, utilizando-se um planejamento experimental fracionário 3² x 2¹. O máximo rendimento obtido foi 1310 U/g ms para a produção de AMG e 50,2 U/g ms para a exo-PG. Comparando-se estes resultados com dados da literatura pode-se dizer que os rendimentos obtidos foram aceitáveis e indicam que o farelo de arroz desengordurado é uma boa fonte de nutrientes. A produção de AMG e exo-PG foi significativamente afetada pelas variáveis cepa de A. niger e tipo de inóculo, enquanto a variável indutor não apresentou influência significativa na produção destas enzimas.

  18. Utilization of gamma rays in the selection of Aspergillus niger for acid production

    International Nuclear Information System (INIS)

    Silva, J.C. da; Azevedo, J.L.

    1978-01-01

    Selection of Aspergillus niger for acid production was studied by the method of Foster and Davis with the use of gamma rays. Three selection cycles were carried out, and the acid production character of each population was analyzed quantitatively by the unitage acid factor. Isolates with high unitage values in relation to the paternal strain were assayed in a liquid fermentation medium. No correlation was found that would indicate unlimited use of Foster and Davis' method in the selection of more productive strains. (Author) [pt

  19. [Progress in omics research of Aspergillus niger].

    Science.gov (United States)

    Sui, Yufei; Ouyang, Liming; Lu, Hongzhong; Zhuang, Yingping; Zhang, Siliang

    2016-08-25

    Aspergillus niger, as an important industrial fermentation strain, is widely applied in the production of organic acids and industrial enzymes. With the development of diverse omics technologies, the data of genome, transcriptome, proteome and metabolome of A. niger are increasing continuously, which declared the coming era of big data for the research in fermentation process of A. niger. The data analysis from single omics and the comparison of multi-omics, to the integrations of multi-omics based on the genome-scale metabolic network model largely extends the intensive and systematic understanding of the efficient production mechanism of A. niger. It also provides possibilities for the reasonable global optimization of strain performance by genetic modification and process regulation. We reviewed and summarized progress in omics research of A. niger, and proposed the development direction of omics research on this cell factory.

  20. Effect of Carum copticum essential oil on growth and aflatoxin formation by Aspergillus strains.

    Science.gov (United States)

    Kazemi, M

    2015-01-01

    The objectives of this study were to determine the antiaflatoxin B1 activity in vitro of the essential oil (EO) extracted from the seeds of Carum copticum and to evaluate its antifungal activity in vivo as a potential food preservative. The C. copticum EO exhibited noticeable inhibition on dry mycelium and synthesis of aflatoxin B1 (AFB1) by Aspergillus flavus, completely inhibiting AFB1 production at 4 μL/mL. C. copticum EOs showed the lowest percentages of decayed cherry tomatoes for all fungi compared with the control at 100 μL/mL with values of 5.01 ± 67% for A. flavus and 5.98 ± 54% for Aspergillus niger. The results indicated that the percentage of infected fruits is significantly (p oil at 100 μL/mL concentration showed the highest inhibition of fungal infection with a value of 80.45% compared with the control. Thus, the EO of dill could be used to control food spoilage and as a potential source of food preservative.

  1. Modification of Aspergillus niger by conducting polymer, Polypyrrole, and the evaluation of electrochemical properties of modified cells.

    Science.gov (United States)

    Apetrei, Roxana-Mihaela; Carac, Geta; Bahrim, Gabriela; Ramanaviciene, Almira; Ramanavicius, Arunas

    2018-06-01

    The enhancement of bioelectrochemical properties of microorganism by in situ formation of conducting polymer within the cell structures (e.g. cell wall) was performed. The synthesis of polypyrrole (Ppy) within fungi (Aspergillus niger) cells was achieved. Two different Aspergillus niger strains were selected due to their ability to produce glucose oxidase, which initiated the Ppy formation through products of enzymatic reaction. The evolution of Ppy structural features was investigated by absorption spectroscopy, cyclic voltammetry and Fourier transform infrared spectroscopy. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. 76 FR 16297 - Aspergillus flavus

    Science.gov (United States)

    2011-03-23

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 180 [EPA-HQ-OPP-2010-0101; FRL-8868-7] Aspergillus... for residues of the microbial pesticide, Aspergillus flavus AF36, in or on corn food and feed... to the existing exemption from the requirement of a tolerance for Aspergillus flavus AF36. This...

  3. Chemodiversity in the genus Aspergillus

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian; Larsen, Thomas Ostenfeld

    2015-01-01

    to be characterized. The genus Aspergillus is cladistically holophyletic but phenotypically polythetic and very diverse and is associated to quite different sexual states. Following the one fungus one name system, the genus Aspergillus is restricted to a holophyletic clade that include the morphologically different...... biosynthetic family isoextrolites. However, it appears that secondary metabolites from one Aspergillus section have analogous metabolites in other sections (here also called heteroisoextrolites). In this review, we give a genus-wide overview of secondary metabolite production in Aspergillus species. Extrolites...

  4. In vivo and in vitro control activity of plant essential oils against three strains of Aspergillus niger.

    Science.gov (United States)

    Kumar, Peeyush; Mishra, Sapna; Kumar, Atul; Kumar, Sanjeev; Prasad, Chandra Shekhar

    2017-09-01

    Contamination of environment and food from the prevalent spores and mycotoxins of Aspergillus niger has led to several diseases in humans and other animals. The present study investigated the control activity of plant essential oils against three strains of A. niger. In the elaborate assays done through microdilution plate assay and agar disk diffusion assay in the lab condition and in vivo assay on the stored wheat grains, the essential oil of Thymus vulgaris depicted overall superior efficacy. In microdilution plate assay, the oil of Anethum graveolens showed best fungistatic activity, while best fungicidal activity was depicted by Syzygium aromaticum oil. The oil of T. vulgaris showed moderate control efficacy against A. niger strains with its antifungal activity resulting mainly due to killing of microorganism rather than growth inhibition. In agar disk diffusion assay, T. vulgaris oil with a zone of inhibition (ZOI) of 23.3-61.1% was the most effective fungicide. The in vivo assay to evaluate the protection efficacy of oils for stored wheat grains against A. niger (AN1) revealed T. vulgaris (90.5-100%) to be the best control agent, followed by the oil of S. aromaticum (61.9-100%). The GC-MS analysis of T. vulgaris oil indicated the presence of thymol (39.11%), γ-terpinene (19.73%), o-cymene (17.21%), and β-pinene (5.38%) as major oil components. Phytotoxic effects of the oils on wheat seeds showed no significant phytotoxic effect of oils in terms of seed germination or seedling growth. The results of the study demonstrated control potentiality of essential oils for the protection of stored wheat against A. niger with prospect for development of eco-friendly antifungal products.

  5. Aspergillus subgenus Polypaecilum from the built environment

    Directory of Open Access Journals (Sweden)

    J.B. Tanney

    2017-09-01

    Full Text Available Xerophilic fungi, especially Aspergillus species, are prevalent in the built environment. In this study, we employed a combined culture-independent (454-pyrosequencing and culture-dependent (dilution-to-extinction approach to investigate the mycobiota of indoor dust collected from 93 buildings in 12 countries worldwide. High and low water activity (aw media were used to capture mesophile and xerophile biodiversity, resulting in the isolation of approximately 9 000 strains. Among these, 340 strains representing seven putative species in Aspergillus subgenus Polypaecilum were isolated, mostly from lowered aw media, and tentatively identified based on colony morphology and internal transcribed spacer rDNA region (ITS barcodes. Further morphological study and phylogenetic analyses using sequences of ITS, β-tubulin (BenA, calmodulin (CaM, RNA polymerase II second largest subunit (RPB2, DNA topoisomerase 1 (TOP1, and a pre-mRNA processing protein homolog (TSR1 confirmed the isolation of seven species of subgenus Polypaecilum, including five novel species: A. baarnensis, A. keratitidis, A. kalimae sp. nov., A. noonimiae sp. nov., A. thailandensis sp. nov., A. waynelawii sp. nov., and A. whitfieldii sp. nov. Pyrosequencing detected six of the seven species isolated from house dust, as well as one additional species absent from the cultures isolated, and three clades representing potentially undescribed species. Species were typically found in house dust from subtropical and tropical climates, often in close proximity to the ocean or sea. The presence of subgenus Polypaecilum, a recently described clade of xerophilic/xerotolerant, halotolerant/halophilic, and potentially zoopathogenic species, within the built environment is noteworthy.

  6. Characterization of the fumonisin B2 biosynthetic gene cluster in Aspergillus niger and A. awamori.

    Science.gov (United States)

    Aspergillus niger and A. awamori strains isolated from grapes cultivated in Mediterranean basin were examined for fumonisin B2 (FB2) production and presence/absence of sequences within the fumonisin biosynthetic gene (fum) cluster. Presence of 13 regions in the fum cluster was evaluated by PCR assay...

  7. Post-genomic insights into the plant polysaccharide degradation potential of Aspergillus nidulans and comparison to Aspergillus niger and Aspergillus oryzae

    DEFF Research Database (Denmark)

    Coutinho, Pedro M.; Andersen, Mikael Rørdam; Kolenova, Katarina

    2009-01-01

    The plant polysaccharide degradative potential of Aspergillus nidulans was analysed in detail and compared to that of Aspergillus niger and Aspergillus oryzae using a combination of bioinformatics, physiology and transcriptomics. Manual verification indicated that 28.4% of the A. nidulans ORFs...... between the Aspergilli in the presence Of putative regulatory sequences in the promoters of the ORFs Of this Study and correlation of the presence Of putative XlnR binding sites to induction by xylose was detected for A. niger. These data demonstrate differences at genome content, Substrate specificity...

  8. New Pathway for Nonphosphorylated Degradation of Gluconate by Aspergillus niger

    Science.gov (United States)

    Elzainy, T. A.; Hassan, M. M.; Allam, A. M.

    1973-01-01

    A new nonphosphorylative pathway for gluconate degradation was found in extracts of a strain of Aspergillus niger. The findings indicate that gluconate is dehydrated into 2-keto-3-deoxy-gluconate (KDG), which then is cleaved into glyceraldehyde and pyruvate. 6-Phosphogluconate was not degraded under the same conditions. In addition, KDG was formed from glyceraldehyde and pyruvate. Very weak activity was obtained when glyceraldehyde 3-phosphate replaced glyceraldehyde in this reaction. PMID:4698214

  9. Atypical Aspergillus parasiticus isolates from pistachio with aflR gene nucleotide insertion identical to Aspergillus sojae

    Science.gov (United States)

    Aflatoxins are the most toxic and carcinogenic secondary metabolites produced primarily by the filamentous fungi Aspergillus flavus and Aspergillus parasiticus. The toxins cause devastating economic losses because of strict regulations on distribution of contaminated products. Aspergillus sojae are...

  10. Secretome data from Trichoderma reesei and Aspergillus niger cultivated in submerged and sequential fermentation methods

    Directory of Open Access Journals (Sweden)

    Camila Florencio

    2016-09-01

    Full Text Available The cultivation procedure and the fungal strain applied for enzyme production may influence levels and profile of the proteins produced. The proteomic analysis data presented here provide critical information to compare proteins secreted by Trichoderma reesei and Aspergillus niger when cultivated through submerged and sequential fermentation processes, using steam-explosion sugarcane bagasse as inducer for enzyme production. The proteins were organized according to the families described in CAZy database as cellulases, hemicellulases, proteases/peptidases, cell-wall-protein, lipases, others (catalase, esterase, etc., glycoside hydrolases families, predicted and hypothetical proteins. Further detailed analysis of this data is provided in “Secretome analysis of Trichoderma reesei and Aspergillus niger cultivated by submerged and sequential fermentation process: enzyme production for sugarcane bagasse hydrolysis” C. Florencio, F.M. Cunha, A.C Badino, C.S. Farinas, E. Ximenes, M.R. Ladisch (2016 [1]. Keywords: Tricoderma reesei, Aspergillus Niger, Enzyme Production, Secretome

  11. Production of plant cell wall degrading enzymes by monoculture and co-culture of Aspergillus niger and Aspergillus terreus under SSF of banana peels

    Directory of Open Access Journals (Sweden)

    Shazia Rehman

    2014-12-01

    Full Text Available Filamentous fungi are considered to be the most important group of microorganisms for the production of plant cell wall degrading enzymes (CWDE, in solid state fermentations. In this study, two fungal strains Aspergillus niger MS23 and Aspergillus terreus MS105 were screened for plant CWDE such as amylase, pectinase, xylanase and cellulases (β-glucosidase, endoglucanase and filterpaperase using a novel substrate, Banana Peels (BP for SSF process. This is the first study, to the best of our knowledge, to use BP as SSF substrate for plant CWDE production by co-culture of fungal strains. The titers of pectinase were significantly improved in co-culture compared to mono-culture. Furthermore, the enzyme preparations obtained from monoculture and co-culture were used to study the hydrolysis of BP along with some crude and purified substrates. It was observed that the enzymatic hydrolysis of different crude and purified substrates accomplished after 26 h of incubation, where pectin was maximally hydrolyzed by the enzyme preparations of mono and co-culture. Along with purified substrates, crude materials were also proved to be efficiently degraded by the cocktail of the CWDE. These results demonstrated that banana peels may be a potential substrate in solid-state fermentation for the production of plant cell wall degrading enzymes to be used for improving various biotechnological and industrial processes.

  12. Production of plant cell wall degrading enzymes by monoculture and co-culture of Aspergillus niger and Aspergillus terreus under SSF of banana peels.

    Science.gov (United States)

    Rehman, Shazia; Aslam, Hina; Ahmad, Aqeel; Khan, Shakeel Ahmed; Sohail, Muhammad

    2014-01-01

    Filamentous fungi are considered to be the most important group of microorganisms for the production of plant cell wall degrading enzymes (CWDE), in solid state fermentations. In this study, two fungal strains Aspergillus niger MS23 and Aspergillus terreus MS105 were screened for plant CWDE such as amylase, pectinase, xylanase and cellulases (β-glucosidase, endoglucanase and filterpaperase) using a novel substrate, Banana Peels (BP) for SSF process. This is the first study, to the best of our knowledge, to use BP as SSF substrate for plant CWDE production by co-culture of fungal strains. The titers of pectinase were significantly improved in co-culture compared to mono-culture. Furthermore, the enzyme preparations obtained from monoculture and co-culture were used to study the hydrolysis of BP along with some crude and purified substrates. It was observed that the enzymatic hydrolysis of different crude and purified substrates accomplished after 26 h of incubation, where pectin was maximally hydrolyzed by the enzyme preparations of mono and co-culture. Along with purified substrates, crude materials were also proved to be efficiently degraded by the cocktail of the CWDE. These results demonstrated that banana peels may be a potential substrate in solid-state fermentation for the production of plant cell wall degrading enzymes to be used for improving various biotechnological and industrial processes.

  13. Molecular characterization of two microalgal strains in Egypt and investigation of the antimicrobial activity of their extracts

    Directory of Open Access Journals (Sweden)

    El Semary, NA.

    2013-01-01

    Full Text Available The emergence of new pathogens and the increasing drug-resistance of recognized ones pose a difficult challenge. One way that this challenge is being addressed is through the discovery of new cost-effective drug resources in the form of bioactive compounds. Algae represent a promising source of bioactive compounds in this regard. In the present research, we used molecular and phylogenetic analysis to isolate and identify two microalgal strains. We found that one strain belonged to the phylum chrysophyta and the other to the cyanobacteria. We also investigated the antimicrobial activity of some of the lipophilic extracts of the two microalgal strains. Several fractions showed high individual antimicrobial bioactivity against multidrug-resistant Salmonella sp., Citrobacter sp., Aspergillus niger and Aspergillus flavus. Fraction III from Poterioochromonas malhamensis showed the highest level of activity against two multidrug-resistant bacterial pathogens. The inhibition zone diameter was 1.4 cm for Salmonella and 1.4 cm for Citrobacter. Meanwhile, another lipophilic fraction from the cyanobacterium Synechocystis salina showed broad-spectrum bioactivity (inhibition zone diameter of 0.9 cm for Aspergillus niger, 1 cm for Citrobacter and 0.9 cm for Salmonella. One lipophilic fraction from Aphanizomenon showed antifungal bioactivity against Aspergillus niger and Aspergillus flavus, where the inhibition zone diameter was 1.1 cm and 1.0 cm, respectively. The study highlights the antimicrobial bioactivity of extracts from local microalgae and emphasizes the importance of carrying out screening programs for those microorganisms.

  14. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry for fast and accurate identification of clinically relevant Aspergillus species.

    Science.gov (United States)

    Alanio, A; Beretti, J-L; Dauphin, B; Mellado, E; Quesne, G; Lacroix, C; Amara, A; Berche, P; Nassif, X; Bougnoux, M-E

    2011-05-01

    New Aspergillus species have recently been described with the use of multilocus sequencing in refractory cases of invasive aspergillosis. The classical phenotypic identification methods routinely used in clinical laboratories failed to identify them adequately. Some of these Aspergillus species have specific patterns of susceptibility to antifungal agents, and misidentification may lead to inappropriate therapy. We developed a matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry (MS)-based strategy to adequately identify Aspergillus species to the species level. A database including the reference spectra of 28 clinically relevant species from seven Aspergillus sections (five common and 23 unusual species) was engineered. The profiles of young and mature colonies were analysed for each reference strain, and species-specific spectral fingerprints were identified. The performance of the database was then tested on 124 clinical and 16 environmental isolates previously characterized by partial sequencing of the β-tubulin and calmodulin genes. One hundred and thirty-eight isolates of 140 (98.6%) were correctly identified. Two atypical isolates could not be identified, but no isolate was misidentified (specificity: 100%). The database, including species-specific spectral fingerprints of young and mature colonies of the reference strains, allowed identification regardless of the maturity of the clinical isolate. These results indicate that MALDI-TOF MS is a powerful tool for rapid and accurate identification of both common and unusual species of Aspergillus. It can give better results than morphological identification in clinical laboratories. © 2010 The Authors. Clinical Microbiology and Infection © 2010 European Society of Clinical Microbiology and Infectious Diseases.

  15. Biodegradation of Pollutants from Winery wastewater by Using Fungi Aspergillus fumigatus and Bacterium Bacillus subtilis

    OpenAIRE

    , C.S. Mahajan; , D.V. Patil; , D.B. Sarode; , R.N. Jadhav; , S.B. Attarde

    2012-01-01

    Aspergillus fumigatus was used as fungal strain and Bacillus subtilis was used as bacterial species for the biodegradation of winery wastewater pollutants. The fungal strain and bacterial species was allowed to grow on PDA and NA slant. Loop full of both fungal and bacterial culture was inoculated and incubated at room temperature for 7 days. After the incubation the sample was filtered and analyzed for the chemical characteristics to verify the degradation capacity of both species,after trea...

  16. Previously unknown species of Aspergillus.

    Science.gov (United States)

    Gautier, M; Normand, A-C; Ranque, S

    2016-08-01

    The use of multi-locus DNA sequence analysis has led to the description of previously unknown 'cryptic' Aspergillus species, whereas classical morphology-based identification of Aspergillus remains limited to the section or species-complex level. The current literature highlights two main features concerning these 'cryptic' Aspergillus species. First, the prevalence of such species in clinical samples is relatively high compared with emergent filamentous fungal taxa such as Mucorales, Scedosporium or Fusarium. Second, it is clearly important to identify these species in the clinical laboratory because of the high frequency of antifungal drug-resistant isolates of such Aspergillus species. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) has recently been shown to enable the identification of filamentous fungi with an accuracy similar to that of DNA sequence-based methods. As MALDI-TOF MS is well suited to the routine clinical laboratory workflow, it facilitates the identification of these 'cryptic' Aspergillus species at the routine mycology bench. The rapid establishment of enhanced filamentous fungi identification facilities will lead to a better understanding of the epidemiology and clinical importance of these emerging Aspergillus species. Based on routine MALDI-TOF MS-based identification results, we provide original insights into the key interpretation issues of a positive Aspergillus culture from a clinical sample. Which ubiquitous species that are frequently isolated from air samples are rarely involved in human invasive disease? Can both the species and the type of biological sample indicate Aspergillus carriage, colonization or infection in a patient? Highly accurate routine filamentous fungi identification is central to enhance the understanding of these previously unknown Aspergillus species, with a vital impact on further improved patient care. Copyright © 2016 European Society of Clinical Microbiology and

  17. Comparative genomics of citric-acid-producing Aspergillus niger ATCC 1015 versus enzyme-producing CBS 513.88

    DEFF Research Database (Denmark)

    Andersen, Mikael Rørdam; Salazar, Margarita Pena; Schaap, Peter J.

    2011-01-01

    The filamentous fungus Aspergillus niger exhibits great diversity in its phenotype. It is found globally, both as marine and terrestrial strains, produces both organic acids and hydrolytic enzymes in high amounts, and some isolates exhibit pathogenicity. Although the genome of an industrial enzyme......-producing A. niger strain (CBS 513.88) has already been sequenced, the versatility and diversity of this species compel additional exploration. We therefore undertook whole-genome sequencing of the acidogenic A. niger wild-type strain (ATCC 1015) and produced a genome sequence of very high quality. Only 15...

  18. Inhibition of citric acid accumulation by manganese ions in Aspergillus niger mutants with reduced citrate control of phosphofructokinase

    Energy Technology Data Exchange (ETDEWEB)

    Schreferl, G.; Kubicek, C.P.; Roehr, M.

    1986-03-01

    Mutant strains of Aspergillus niger with reduced citrate control of carbohydrate catabolism (cic mutants) grow faster than the parent strain on media containing 5% (wt/vol) citrate. The mutants tolerated a higher intracellular citrate concentration than the parent strain. One mutant (cic-7/3) contained phosphofructokinase activity significantly less sensitive towards citrate than the enzyme from the parent strain. When this mutant was grown under citrate accumulating conditions, acidogenesis was far less sensitive to inhibition by Mn/sup 2 +/ than in the parent strain. Some of the cic mutants also showed altered citrate inhibition of NADP-specific isocitrate dehydrogenase.

  19. Disruption of the L-arabitol dehydrogenase encoding gene in Aspergillus tubingensis results in increased xylanase production

    NARCIS (Netherlands)

    Nikolaev, I.; Hansen, S.; Madrid, S.; de Vries, R.P.

    2013-01-01

    Fungal xylanases are of major importance to many industrial sectors, such as food and feed, paper and pulp, and biofuels. Improving their production is therefore highly relevant. We determined the molecular basis of an improved xylanase-producing strain of Aspergillus tubingensis that was generated

  20. Aspergillus westerdijkiae as a major ochratoxin A risk in dry-cured ham based-media.

    Science.gov (United States)

    Vipotnik, Ziva; Rodríguez, Alicia; Rodrigues, Paula

    2017-01-16

    Penicillium nordicum is well known for its ability to produce high amounts of ochratoxin A (OTA) in cured meat-derived products. On the other hand, Aspergillus westerdijkiae, one of the most relevant OTA-producing species of the genus Aspergillus, is usually considered a major risk in carbon-rich food matrices of plant origin. The objective of this work was to evaluate, for the first time, the ecophysiological conditions governing growth, OTA production and sporulation of A. westerdijkiae (the type-strain and one ham-native strain), in comparison with P. nordicum, in dry-cured ham based medium. For that purpose, the interaction between temperature (15, 20, 25 and 30°C) and water activity (a w ) (0.99, 0.97, 0.93, 0.90 and 0.85), achieved with a combination of ionic (NaCl) and non-ionic (glycerol) solutes, was studied by using dry-cured ham-based medium as a model system. Different OTA production profiles were found between the two genera, and also between the two strains of A. westerdijkiae, mostly in terms of amounts of OTA produced. The optimal OTA production conditions for A. westerdijkiae were at 0.94-0.97 a w and 20-25°C, and for P. nordicum at 0.95-0.97 a w between 18 and 22°C. Under these conditions, A. westerdijkiae produced 1934ng/g agar, while P. nordicum produced 712ng/g. None of the strains was able to produce detectable amounts of OTA at 0.85 a w , under all temperatures tested. Growth and sporulation were not good indicators of OTA production by A. westerdijkiae or P. nordicum. The results obtained show that A. westerdijkiae may represent a great potential risk of OTA contamination in dry-cured ham due to the high production under a wide range of conditions. Knowledge of the ecophysiology of important Aspergillus and Penicillium species and of their adaptability to the matrices can be determinant to adopt appropriate technological modifications during ham ripening process. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Single-step production of the simvastatin precursor monacolin J by engineering of an industrial strain of Aspergillus terreus.

    Science.gov (United States)

    Huang, Xuenian; Liang, Yajing; Yang, Yong; Lu, Xuefeng

    2017-07-01

    Monacolin J is a key precursor for the synthesis of simvastatin (Zocor), an important drug for treating hypercholesterolemia. Industrially, monacolin J is manufactured through alkaline hydrolysis of lovastatin, a fungal polyketide produced by Aspergillus terreus. Multistep chemical processes for the conversion of lovastatin to simvastatin are laborious, cost expensive and environmentally unfriendly. A biocatalysis process for monacolin J conversion to simvastatin has been developed. However, direct bioproduction of monacolin J has not yet been achieved. Here, we identified a lovastatin hydrolase from Penicillium chrysogenum, which displays a 232-fold higher catalytic efficiency for the in vitro hydrolysis of lovastatin compared to a previously patented hydrolase, but no activity for simvastatin. Furthermore, we showed that an industrial A. terreus strain heterologously expressing this lovastatin hydrolase can produce monacolin J through single-step fermentation with high efficiency, approximately 95% of the biosynthesized lovastatin was hydrolyzed to monacolin J. Our results demonstrate a simple and green technical route for the production of monacolin J, which makes complete bioproduction of the cholesterol-lowering drug simvastatin feasible and promising. Copyright © 2017 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  2. Genome sequencing and analysis of the versatile cell factory Aspergillus niger CBS 513.88

    DEFF Research Database (Denmark)

    Pel, Herman J.; de Winde, Johannes H.; Archer, David B.

    2007-01-01

    The filamentous fungus Aspergillus niger is widely exploited by the fermentation industry for the production of enzymes and organic acids, particularly citric acid. We sequenced the 33.9-megabase genome of A. niger CBS 513.88, the ancestor of currently used enzyme production strains. A high level...... clusters for fumonisin and ochratoxin A synthesis....

  3. Improvement in citric acid production of Aspergillus niger ATCC 11414 by radiation

    International Nuclear Information System (INIS)

    Pewlong, Wachiraporn; Sansakorn, Sujittra; Puntharakratchadej, Chanin

    2003-10-01

    Ultraviolet and gamma irradiation were used to induce mutation of Aspergillus niger ATCC 11414 in order to increase ability of citric acid production. Five mutants of high-producing citric acid were 7UV-18, A2-14, 9UV-2, 9UV-27 and 8UV-10. The yields of citric acid were 2.0 to 3.84 fold higher than that of the wild type strain

  4. Taxonomic Characterization and Secondary Metabolite Profiling of Aspergillus Section Aspergillus Contaminating Feeds and Feedstuffs

    Science.gov (United States)

    Greco, Mariana; Kemppainen, Minna; Pose, Graciela; Pardo, Alejandro

    2015-01-01

    Xerophilic fungal species of the genus Aspergillus are economically highly relevant due to their ability to grow on low water activity substrates causing spoilage of stored goods and animal feeds. These fungi can synthesize a variety of secondary metabolites, many of which show animal toxicity, creating a health risk for food production animals and to humans as final consumers, respectively. Animal feeds used for rabbit, chinchilla and rainbow trout production in Argentina were analysed for the presence of xerophilic Aspergillus section Aspergillus species. High isolation frequencies (>60%) were detected in all the studied rabbit and chinchilla feeds, while the rainbow trout feeds showed lower fungal charge (25%). These section Aspergillus contaminations comprised predominantly five taxa. Twenty isolates were subjected to taxonomic characterization using both ascospore SEM micromorphology and two independent DNA loci sequencing. The secondary metabolite profiles of the isolates were determined qualitatively by HPLC-MS. All the isolates produced neoechinulin A, 17 isolates were positive for cladosporin and echinulin, and 18 were positive for neoechinulin B. Physcion and preechinulin were detected in a minor proportion of the isolates. This is the first report describing the detailed species composition and the secondary metabolite profiles of Aspergillus section Aspergillus contaminating animal feeds. PMID:26364643

  5. Taxonomic Characterization and Secondary Metabolite Profiling of Aspergillus Section Aspergillus Contaminating Feeds and Feedstuffs

    Directory of Open Access Journals (Sweden)

    Mariana Greco

    2015-09-01

    Full Text Available Xerophilic fungal species of the genus Aspergillus are economically highly relevant due to their ability to grow on low water activity substrates causing spoilage of stored goods and animal feeds. These fungi can synthesize a variety of secondary metabolites, many of which show animal toxicity, creating a health risk for food production animals and to humans as final consumers, respectively. Animal feeds used for rabbit, chinchilla and rainbow trout production in Argentina were analysed for the presence of xerophilic Aspergillus section Aspergillus species. High isolation frequencies (>60% were detected in all the studied rabbit and chinchilla feeds, while the rainbow trout feeds showed lower fungal charge (25%. These section Aspergillus contaminations comprised predominantly five taxa. Twenty isolates were subjected to taxonomic characterization using both ascospore SEM micromorphology and two independent DNA loci sequencing. The secondary metabolite profiles of the isolates were determined qualitatively by HPLC-MS. All the isolates produced neoechinulin A, 17 isolates were positive for cladosporin and echinulin, and 18 were positive for neoechinulin B. Physcion and preechinulin were detected in a minor proportion of the isolates. This is the first report describing the detailed species composition and the secondary metabolite profiles of Aspergillus section Aspergillus contaminating animal feeds.

  6. Taxonomic Characterization and Secondary Metabolite Profiling of Aspergillus Section Aspergillus Contaminating Feeds and Feedstuffs.

    Science.gov (United States)

    Greco, Mariana; Kemppainen, Minna; Pose, Graciela; Pardo, Alejandro

    2015-09-02

    Xerophilic fungal species of the genus Aspergillus are economically highly relevant due to their ability to grow on low water activity substrates causing spoilage of stored goods and animal feeds. These fungi can synthesize a variety of secondary metabolites, many of which show animal toxicity, creating a health risk for food production animals and to humans as final consumers, respectively. Animal feeds used for rabbit, chinchilla and rainbow trout production in Argentina were analysed for the presence of xerophilic Aspergillus section Aspergillus species. High isolation frequencies (>60%) were detected in all the studied rabbit and chinchilla feeds, while the rainbow trout feeds showed lower fungal charge (25%). These section Aspergillus contaminations comprised predominantly five taxa. Twenty isolates were subjected to taxonomic characterization using both ascospore SEM micromorphology and two independent DNA loci sequencing. The secondary metabolite profiles of the isolates were determined qualitatively by HPLC-MS. All the isolates produced neoechinulin A, 17 isolates were positive for cladosporin and echinulin, and 18 were positive for neoechinulin B. Physcion and preechinulin were detected in a minor proportion of the isolates. This is the first report describing the detailed species composition and the secondary metabolite profiles of Aspergillus section Aspergillus contaminating animal feeds.

  7. Malic acid production by chemically induced Aspergillus niger MTCC 281 mutant from crude glycerol.

    Science.gov (United States)

    Iyyappan, J; Bharathiraja, B; Baskar, G; Jayamuthunagai, J; Barathkumar, S; Anna Shiny, R

    2018-03-01

    In the present investigation, crude glycerol derived from transesterification process was utilized to produce the commercially-valuable malic acid. A combined resistant on methanol and malic acid strain of Aspergillus niger MTCC 281 mutant was generated in solid medium containing methanol (1-5%) and malic acid (40-80 g/L) by the adaptation process for 22 weeks. The ability of induced Aspergillus niger MTCC 281 mutant to utilize crude glycerol and pure glycerol to produce malic acid was studied. The yield of malic acid was increased with 4.45 folds compared with that of parent strain from crude glycerol. The highest concentration of malic acid from crude glycerol by using beneficial mutant was found to be 77.38 ± 0.51 g/L after 192 h at 25 °C. This present study specified that crude glycerol by-product from biodiesel production could be used for producing high amount of malic acid without any pretreatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Enhancement of epoxide hydrolase production by 60 Co gamma and UV irradiation mutagenesis of Aspergillus niger ZJB-09103.

    Science.gov (United States)

    Jin, Huo-Xi; OuYang, Xiao-Kun; Hu, Zhong-Ce

    2017-05-01

    An effective epoxide hydrolase (EH) production strain was mutagenized using 60 Co gamma and UV irradiation. Among positive mutant strains, the EH activity of C2-44 reached 33.7 U/g, which was 267% as much as that of the original Aspergillus niger ZJB-09103. Compared with the wild type, there were significant changes in morphology for C2-44, including the color of mycelia on the slants and the shape of conidial head. In addition, glucose and soybean cake were the optimal carbon and nitrogen source in terms of EH activity for the mutant C2-44 instead of soluble starch and peptone for the wild-type strain. The reaction time required to reach 99% enantiomeric excesses of (S)-epichlorohydrin from racemic substrate was shortened significantly by the mutant C2-44. This phenomenon was probably explained by the higher V max for hydrolysis of racemic epichlorohydrin by C2-44 compared with Aspergillus niger ZJB-09103. © 2016 International Union of Biochemistry and Molecular Biology, Inc.

  9. Influence of gamma-rays and some cultural conditions on the enhancement of cellulase production by some fungal strains isolated from cellulosic wastes

    International Nuclear Information System (INIS)

    Aziz, N.H.; Abo-State, M.A.; Girigs, A.M.P.; Youssef, Kh.A.; El-Mahalawy, A.A.

    2010-01-01

    In the present study, out of 51 fungal strains isolated from the cellulosic wastes, only 19 were CMCase-producers. Aspergillus, Fusarium and Penicillium were the most common fungal genera isolated from the cellulosic wastes. Fusarium neoceras, Aspergillus fumigatus and Fusarium oxysporium produced CMCase activity than Trichoderma viride. Out of 23 gamma-irradiated survivors from A.fumigatus and F. neoceras showing CMCase production, only two mutant strains A.fumigatus 8G-2 and F. neoceras 4G-2 produced the highest levels of CMCase than the parent strains. The results indicated that the maximum level of of CMCase activity was produced by A.fumigatus and F. neoceras strains under optiminizing conditions.

  10. Effect of temperature and water activity on the production of fumonisins by Aspergillus niger and different Fusarium species

    NARCIS (Netherlands)

    Mogensen, J.M.; Nielsen, K.F.; Samson, R.A.; Frisvad, J.C.; Thrane, U.

    2009-01-01

    ABSTRACT: BACKGROUND: Fumonisins are economically important mycotoxins which until recently were considered to originate from only a few Fusarium species. However recently a putative fumonisin gene cluster was discovered in two different Aspergillus niger strains followed by detection of an actual

  11. A molecular analysis of L-arabinan degradation in Aspergillus niger and Aspergillus nidulans

    NARCIS (Netherlands)

    Flipphi, M.J.A.

    1995-01-01

    This thesis describes a molecular study of the genetics ofL-arabinan degradation in Aspergillus niger and Aspergillus nidulans. These saprophytic hyphal fungi produce an extracellular hydrolytic enzyme system to

  12. Allergens/Antigens, Toxins and Polyketides of Important Aspergillus Species

    OpenAIRE

    Bhetariya, Preetida J.; Madan, Taruna; Basir, Seemi Farhat; Varma, Anupam; Usha, Sarma P.

    2011-01-01

    The medical, agricultural and biotechnological importance of the primitive eukaryotic microorganisms, the Fungi was recognized way back in 1920. Among various groups of fungi, the Aspergillus species are studied in great detail using advances in genomics and proteomics to unravel biological and molecular mechanisms in these fungi. Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Aspergillus parasiticus, Aspergillus nidulans and Aspergillus terreus are some of the important specie...

  13. Enhanced aflatoxin production by aspergillus parasiticus and aspergillus flavus after low dose gamma irradiation

    International Nuclear Information System (INIS)

    Ito, Hitoshi

    1992-01-01

    Spores of Aspergillus parasiticus IFO 30179 and A. flavus var. columnaris S46 were irradiated at 0.05, 0.2 and 0.4 kGy in the synthetic low salts (SL) broth, and the effect on aflatoxin production was examined after 10 days incubation at 30 or 25degC. In these two strains, irradiation of spores at 0.05 kGy resulted in higher B1 or G1 production than the non-irradiated controles. However, spores of the both strains irradiated at 0.2 or 0.4 kGy produced less aflatoxins than non-irradiated controles. In the SL broth, apparent stimulation by low dose irradiation was slight, and these enhanced effects were not observed after reinfection to fresh SL broth. In the case of food samples, the levels of aflatoxin B 1 and G 1 with A. parasiticus were increased from 15 to 90% by incubation of irradiated spores at 1 kGy in autoclaved polished rice, black pepper, white pepper and red pepper. These enhancement would be induced by change of composition in each substrates. Mutations of fungi induced by irradiation is not effective for enhancement of aflatoxin production. (author)

  14. First Report of an Atypical New Aspergillus parasiticus Isolates with Nucleotides Insertion in aflR Gene Identical to Aspergillus sojae

    Science.gov (United States)

    Aflatoxins are toxic and carcinogenic secondary metabolites produced primarily by the filamentous fungi Aspergillus favus and Aspergillus parasitic and cause toxin contamination in food chain worldwide. Aspergillus oryzae and Aspergillus sojae are highly valued as koji molds in the traditional prep...

  15. Preliminary Study and Improve the Production of Metabolites with Antifungal Activity by A Bacillus Sp Strain IBA 33

    Directory of Open Access Journals (Sweden)

    María Antonieta Gordillo

    2009-01-01

    Full Text Available Bacillus sp strain IBA 33 metabolites, isolated from decaying lemon fruits, were evaluated for the control of pathogenic and non-pathogenic fungi (Penicillium digitatum, Geotrichum candidum, Penicillium expansum, Aspergillus clavatus, Aspergillus flavus, Aspergillus niger, and Fusarium moniliforme. These metabolites were recovered from Landy medium (LM without aminoacids. In order to optimize metabolites production the LM was modified by adding different concentrations and sources of amino acids and carbohydrates at different culture conditions.Bacillus sp strain IBA 33 metabolites efficacy to control fungi were evaluated with in vitro and in vivo assays. A. flavus growth inhibition was 52% with the metabolites of Bacillus sp strain IBA 33 recovered from LM (MBLM in vitro assays. MBLM supplemented with 0.5% glutamic acid, inhibited the growth of P. digitatum, G. candidum, A. clavatus, A. niger and F. moniliforme by 65%, 88.44%, 84%, 34% and 92% respectively. The highest inhibition of P. expansum was 45% with MBLM supplemented with 0.5% aspartic acid. Similar results were obtained in vivo assays. These results showed that Bacillus sp strain IBA 33 metabolites specificity against fungi depended on the composition of the LM.

  16. Preliminary Study and Improve the Production of Metabolites with Antifungal Activity by A Bacillus Sp Strain IBA 33

    Directory of Open Access Journals (Sweden)

    María Antonieta Gordillo

    2009-04-01

    Full Text Available Bacillus sp strain IBA 33 metabolites, isolated from decaying lemon fruits, were evaluated for the control of pathogenic and non-pathogenic fungi (Penicillium digitatum, Geotrichum candidum, Penicillium expansum, Aspergillus clavatus, Aspergillus flavus, Aspergillus niger, and Fusarium moniliforme. These metabolites were recovered from Landy medium (LM without aminoacids. In order to optimize metabolites production the LM was modified by adding different concentrations and sources of amino acids and carbohydrates at different culture conditions. Bacillus sp strain IBA 33 metabolites efficacy to control fungi were evaluated with in vitro and in vivo assays. A. flavus growth inhibition was 52% with the metabolites of Bacillus sp strain IBA 33 recovered from LM (MBLM in vitro assays. MBLM supplemented with 0.5% glutamic acid, inhibited the growth of P. digitatum, G. candidum, A. clavatus, A. niger and F. moniliforme by 65%, 88.44%, 84%, 34% and 92% respectively. The highest inhibition of P. expansum was 45% with MBLM supplemented with 0.5% aspartic acid. Similar results were obtained in vivo assays. These results showed that Bacillus sp strain IBA 33 metabolites specificity against fungi depended on the composition of the LM.

  17. In vitro susceptibility testing of Aspergillus spp. against voriconazole, itraconazole, posaconazole, amphotericin B and caspofungin.

    Science.gov (United States)

    Shi, Jun-yan; Xu, Ying-chun; Shi, Yi; Lü, Huo-xiang; Liu, Yong; Zhao, Wang-sheng; Chen, Dong-mei; Xi, Li-yan; Zhou, Xin; Wang, He; Guo, Li-na

    2010-10-01

    During recent years, the incidence of serious infections caused by opportunistic fungi has increased dramatically due to alterations of the immune status of patients with hematological diseases, malignant tumors, transplantations and so forth. Unfortunately, the wide use of triazole antifungal agents to treat these infections has lead to the emergence of Aspergillus spp. resistant to triazoles. The present study was to assess the in vitro activities of five antifungal agents (voriconazole, itraconazole, posaconazole, amphotericin B and caspofungin) against different kinds of Aspergillus spp. that are commonly encountered in the clinical setting. The agar-based Etest MIC method was employed. One hundred and seven strains of Aspergillus spp. (5 species) were collected and prepared according to Etest Technique Manuel. Etest MICs were determined with RPMI agar containing 2% glucose and were read after incubation for 48 hours at 35°C. MIC(50), MIC(90) and MIC range were acquired by Whonet 5.4 software. The MIC(90) of caspofungin against A. fumigatus, A. flavus and A. nidulans was 0.094 µg/ml whereas the MIC(90) against A. niger was 0.19 µg/ml. For these four species, the MIC(90) of caspofungin was the lowest among the five antifungal agents. For A. terrus, the MIC(90) of posaconazole was the lowest. For A. fumigatus and A. flavus, the MIC(90) in order of increasing was caspofungin, posaconazole, voriconazole, itraconazole, and amphotericin B. The MIC of amphotericin B against A. terrus was higher than 32 µg/ml in all 7 strains tested. The in vitro antifungal susceptibility test shows the new drug caspofungin, which is a kind of echinocandins, has good activity against the five species of Aspergillus spp. and all the triazoles tested have better in vitro activity than traditional amphotericin B.

  18. Targeted tandem duplication of a large chromosomal segment in Aspergillus oryzae.

    Science.gov (United States)

    Takahashi, Tadashi; Sato, Atsushi; Ogawa, Masahiro; Hanya, Yoshiki; Oguma, Tetsuya

    2014-08-01

    We describe here the first successful construction of a targeted tandem duplication of a large chromosomal segment in Aspergillus oryzae. The targeted tandem chromosomal duplication was achieved by using strains that had a 5'-deleted pyrG upstream of the region targeted for tandem chromosomal duplication and a 3'-deleted pyrG downstream of the target region. Consequently,strains bearing a 210-kb targeted tandem chromosomal duplication near the centromeric region of chromosome 8 and strains bearing a targeted tandem chromosomal duplication of a 700-kb region of chromosome 2 were successfully constructed. The strains bearing the tandem chromosomal duplication were efficiently obtained from the regenerated protoplast of the parental strains. However, the generation of the chromosomal duplication did not depend on the introduction of double-stranded breaks(DSBs) by I-SceI. The chromosomal duplications of these strains were stably maintained after five generations of culture under nonselective conditions. The strains bearing the tandem chromosomal duplication in the 700-kb region of chromosome 2 showed highly increased protease activity in solid-state culture, indicating that the duplication of large chromosomal segments could be a useful new breeding technology and gene analysis method.

  19. Identification of clinical isolates of Aspergillus, including cryptic species, by matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS).

    Science.gov (United States)

    Vidal-Acuña, M Reyes; Ruiz-Pérez de Pipaón, Maite; Torres-Sánchez, María José; Aznar, Javier

    2017-12-08

    An expanded library of matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been constructed using the spectra generated from 42 clinical isolates and 11 reference strains, including 23 different species from 8 sections (16 cryptic plus 7 noncryptic species). Out of a total of 379 strains of Aspergillus isolated from clinical samples, 179 strains were selected to be identified by sequencing of beta-tubulin or calmodulin genes. Protein spectra of 53 strains, cultured in liquid medium, were used to construct an in-house reference database in the MALDI-TOF MS. One hundred ninety strains (179 clinical isolates previously identified by sequencing and the 11 reference strains), cultured on solid medium, were blindy analyzed by the MALDI-TOF MS technology to validate the generated in-house reference database. A 100% correlation was obtained with both identification methods, gene sequencing and MALDI-TOF MS, and no discordant identification was obtained. The HUVR database provided species level (score of ≥2.0) identification in 165 isolates (86.84%) and for the remaining 25 (13.16%) a genus level identification (score between 1.7 and 2.0) was obtained. The routine MALDI-TOF MS analysis with the new database, was then challenged with 200 Aspergillus clinical isolates grown on solid medium in a prospective evaluation. A species identification was obtained in 191 strains (95.5%), and only nine strains (4.5%) could not be identified at the species level. Among the 200 strains, A. tubingensis was the only cryptic species identified. We demonstrated the feasibility and usefulness of the new HUVR database in MALDI-TOF MS by the use of a standardized procedure for the identification of Aspergillus clinical isolates, including cryptic species, grown either on solid or liquid media. © The Author 2017. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For

  20. An adaptive response to alkylating agents in Aspergillus nidulans.

    Science.gov (United States)

    Hooley, P; Shawcross, S G; Strike, P

    1988-11-01

    A simple method is described for demonstrating adaptation to alkylation damage in Aspergillus nidulans. One wild type, two MNNG-sensitive, and one MNNG-resistant strain all showed improvement in colony growth when challenged with MNNG following appropriate inducing pretreatments. Other alkylating agents (MMS, EMS) could also adapt mycelium to later MNNG challenge, while 4NQO and UV could not. The inducible effect was not transmissible through conidia. A standard reversion assay based upon methG proved impractical for studying mutation frequencies during alkylation treatments owing to variations in MNNG resistance amongst revertants.

  1. Microbial Observatory (ISS-MO): Draft Genome Sequence of two Aspergillus fumigatus Strains Isolated from the International Space Station

    Data.gov (United States)

    National Aeronautics and Space Administration — Aspergillus fumigatus is a saprophytic filamentous fungus that is ubiquitous outdoors (soil decaying vegetation) and indoors (hospitals simulated closed habitats...

  2. A comparative secretome analysis of industrial Aspergillus oryzae and its spontaneous mutant ZJGS-LZ-21.

    Science.gov (United States)

    Zhu, Yuanyuan; Liang, Xinle; Zhang, Hong; Feng, Wei; Liu, Ye; Zhang, Fuming; Linhardt, Robert J

    2017-05-02

    Aspergillus oryzae koji plays a crucial role in fermented food products due to the hydrolytic activities of secreted enzymes. In the present study, we performed a comparative secretome analysis of the industrial strain of Aspergillus oryzae 3.042 and its spontaneous mutantZJGS-LZ-21. One hundred and fifty two (152) differential protein spots were excised (p<0.05), and 25 proteins were identified. Of the identified proteins, 91.3% belonged to hydrolytic enzymes acting on carbohydrates or proteins. Consistent with their enzyme activities, the expression of 14 proteins involved in the degradation of cellulose, hemicellulose, starch and proteins, increased in the ZJGS-LZ-21isolate. In particular, increased levels of acid protease (Pep) may favor the degradation of soy proteins in acidic environments and promote the cleavage of allergenic soybean proteins in fermentation, resulting in improvements of product safety and quality. The ZJGS-LZ-21 isolate showed higher protein secretion and increased hydrolytic activities than did strain 3.042, indicating its promising application in soybean paste fermentation. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. The chemical heritage of Aspergillus flavus in A. oryzae RIB 40

    OpenAIRE

    Rank, Christian; Klejnstrup, Marie Louise; Petersen, Lene Maj; Frisvad, Jens Christian; Larsen, Thomas Ostenfeld

    2011-01-01

    Aspergillus oryzae is a very important species in biotechnology and has been used for centuries in traditional Asian fermentation. The RIB40 strain is particularly interesting as it was one of the first genome sequenced Aspergilli together with A. flavus, a prominent food and feed contaminant capable of producing aflatoxin. These species can be perceived as ecotypes. We have analyzed A. oryzae RIB40 and found that the chemical potential could be enhanced significantly under certain conditions...

  4. Aspergillus species as emerging causative agents of onychomycosis.

    Science.gov (United States)

    Nouripour-Sisakht, S; Mirhendi, H; Shidfar, M R; Ahmadi, B; Rezaei-Matehkolaei, A; Geramishoar, M; Zarei, F; Jalalizand, N

    2015-06-01

    Onychomycosis is a common nail infection caused by dermatophytes, non-dermatophyte molds (NDM), and yeasts. Aspergillus species are emerging as increasing causes of toenail onychomycosis. The purpose of this study was species delineation of Aspergillus spp. isolated from patients with onychomycosis. During a period of one year (2012-2013), nail samples were collected from patients clinically suspected of onychomycosis and subjected to microscopic examination and culture. Species identification was performed based on macro- and micro-morphology of colonies. For precise species identification, PCR-amplification and sequencing of the beta-tubulin gene followed by BLAST queries were performed where required. A total of 463/2,292 (20.2%) tested nails were diagnosed with onychomycosis. Among the positive specimens, 154 cases (33.2%) were identified as saprophytic NDM onychomycosis, 135 (29.2%) of which were attributable to Aspergillus. Aspergillus species isolated from the infected nails included Aspergillus flavus (77.3%, n=119), Aspergillus niger (n=4), Aspergillus tubingensis (n=4), Aspergillus terreus (n=3), Aspergillus sydowii (n=2), Aspergillus spp. (n=2), and Aspergillus candidus (n=1). Among the patients diagnosed with onychomycosis due to Aspergillus (average patient age, 47.4 years), 40 had fingernail and 95 toenail involvement. The large toenails were most commonly affected. This study identified a markedly high occurrence of A. flavus, and this fungus appears to be an emerging cause of saprophytic onychomycosis in Iran. The study moreover highlights the necessity of differentiating between dermatophytic and non-dermatophytic nail infections for informed decisions on appropriate therapy. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  5. The mutagenic effect of near ultraviolet light on the nvs strains of Aspergillus nidulans in the presence of 8-metoxypsoralen or angelicin

    International Nuclear Information System (INIS)

    Muronets, E.M.; Kovtunenko, L.V.; Kameneva, S.V.

    1980-01-01

    The mutual mutagenic effect of long-wave ultraviolet radiation (EUV) with angelicin which forms monoadducts in DNA and 8-metoxypsoralen (8 MOP) which forms monoadducts and joints, on conidia of uvs- and uvs+ strains of Aspergillus nidulans, is studied. The two types of interaction are shown to induce mutations intensively. Mutation induction with angelicin shows the role of psoralen pyrimidine monoadducts in mutagenesis. The technique of fractionated EUV radiation and studying the effect of monoadduct repair effectiveness on mutation output permits to prove that interthread DNA joints induced by 8-MOP+EUV are also highly mutagenous. The products of UVS/2, 20b, 26 genes which take part in the excision of DNA damages do not take part in the formation of mutations induced in aspergil by furocoumarine + EUV. The products of uvs 19, 20a genes which take part in the postreplicative DNA reduction are neccessary for the repair of premutation damages induced by furocoumarine + EUV

  6. Isolation, screening and characterization of a novel extracellular xylanase from Aspergillus niger (KP874102.1) and its application in orange peel hydrolysis.

    Science.gov (United States)

    Uday, Uma Shankar Prasad; Majumdar, Ria; Tiwari, Onkar Nath; Mishra, Umesh; Mondal, Abhijit; Bandyopadhyay, Tarun Kanti; Bhunia, Biswanath

    2017-12-01

    In the present work, a potent xylanase producing fungal strain Aspergillus niger (KP874102.1) was isolated through cultural and morphological observations from soil sample of Baramura forest, Tripura west, India. 28S rDNA technique was applied for genomic identification of this fungal strain. The isolated strain was found to be phylogenetically closely related to Aspergillus niger. Kinetic constants such as K m and V max for extracellular xylanase were determined using various substrate such as beech wood xylan, oat spelt xylan and CM cellulose through Lineweaver-Burk plot. K m , V max and K cat for beech wood xylan are found to be 2.89mg/ml, 2442U and 426178Umlmg -1 respectively. Crude enzyme did not show also CM cellulose activity. The relative efficiency of oat spelt xylan was found to be 0.819 with respect to beech wood xylan. After acid hydrolysis, enzyme was able to produce reducing sugar with 17.7, 35.5, 50.8 and 65% (w/w) from orange peel after 15, 30, 45 and 60min incubation with cellulase free xylanase and maximum reducing sugar formation rate was found to be 55.96μg/ml/min. Therefore, the Aspergillus niger (KP874102.1) is considered as a potential candidate for enzymatic hydrolysis of orange peel. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Immobilization of an L-aminoacylase-producing strain of Aspergillus oryzae into gelatin pellets and its application in the resolution of D,L-methionine.

    Science.gov (United States)

    Yuan Yj, Ying-jin; Wang Sh, Shu-hao; Song Zx, Zheng-xiao; Gao Rc, Rui-chang

    2002-04-01

    The conditions for immobilization of an l-aminoacylase-producing strain of Aspergillus oryzae in gelatin and the enzymic characteristics of the immobilized pellets were studied. The optimal concentrations of gelatin, glutaraldehyde and ethyldiamine and time of immobilization were determined. Scanning electron micrographs reveal the cross-linked structure differences between the native and immobilized pellets. Optimum pH and temperature of the native and immobilized pellets were determined. Effects of ionic strength and substrate concentration on relative activity of the native and immobilized pellets were investigated in detail. The immobilized pellets were more stable over broader temperature and pH ranges. In addition, the immobilized pellets showed stable activity under operational and storage conditions. The immobilized pellets lost about 20% of their initial activity after five cycles of reuse. The results reported in this paper show the potential for using the immobilized A. oryzae pellets to resolve d,l-methionine.

  8. Cr(VI) reduction from contaminated soils by Aspergillus sp. N2 and Penicillium sp. N3 isolated from chromium deposits.

    Science.gov (United States)

    Fukuda, Tsubasa; Ishino, Yasuhiro; Ogawa, Akane; Tsutsumi, Kadzuyo; Morita, Hiroshi

    2008-10-01

    Aspergillus sp. N2 and Penicillium sp. N3 are chromate-resistant filamentous fungi that were isolated from Cr(VI) contaminated soil based on their ability to decrease hexavalent chromium levels in the growth medium. After 120 h of growth in a medium containing 50 ppm Cr(VI) at near neutral pH, Aspergillus sp. N2 reduced the Cr(VI) concentration by about 75%. Penicillium sp. N3 was able to reduce the Cr(VI) concentration by only 35%. However, Penicillium sp. N3 reduced the Cr(VI) concentration in the medium by 93% under acidic conditions. Interestingly, the presence of Cu(II) enhanced the Cr(VI) reducing ability of Aspergillus sp. N2 and Penicillium sp. N3 at near neutral pH. Aspergillus sp. N2 and Penicillium sp. N3 reduced the Cr(VI) concentration in the growth medium to a virtually undetectable level within 120 h. For both Aspergillus sp. N2 and Penicillium sp. N3, mycelial seed cultures were more efficient at Cr(VI) reduction than conidium seed cultures. The mechanisms of Cr(VI) reduction in Aspergillus sp. N2 and Penicillium sp. N3 were enzymatic reduction and sorption to mycelia. Enzymatic activity contributed significantly to Cr(VI) reduction. Aspergillus sp. N2 and Penicillium sp. N3 reduced the levels of Cr(VI) in polluted soil samples, suggesting that these strains might be useful for cleaning up chromium-contaminated sites.

  9. Biosolubilization of poorly soluble rock phosphates by Aspergillus tubingensis and Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, M.S.; Kumar, S.; Babita, K. [Thapar Institute of Engineering and Technology, Patiala (India). School of Biotechnology; Reddy, M.S. [Auburn University, AL (United States). Department of Entomology and Plant Pathology

    2002-09-01

    Three isolates of Aspergillus tubingensis and two isolates of Aspergillus niger isolated from rhizospheric soils were tested on solubilization of different rock phosphates. All the isolates of Aspergillus were capable of solubilizing all the natural rock phosphates. A. tubingensis (AT1) showed maximum percent solubilization in all the rock phosphates tested in this study when compared to other isolates. This isolate also showed highest phosphorus (P) solubilization when grown in the presence of 2% of rock phosphate. A. tubingensis (AT1) seems to be more efficient in solubilization of rock phosphates compared to other isolates reported elsewhere. This is the first report of rock phosphate solubilization by A. tubingensis and might provide an efficient large scale biosolubilization of rock phosphates intended for P fertilizer. (author)

  10. Structural and functional insights of β-glucosidases identified from the genome of Aspergillus fumigatus

    Science.gov (United States)

    Dodda, Subba Reddy; Aich, Aparajita; Sarkar, Nibedita; Jain, Piyush; Jain, Sneha; Mondal, Sudipa; Aikat, Kaustav; Mukhopadhyay, Sudit S.

    2018-03-01

    Thermostable glucose tolerant β-glucosidase from Aspergillus species has attracted worldwide interest for their potentiality in industrial applications and bioethanol production. A strain of Aspergillus fumigatus (AfNITDGPKA3) identified by our laboratory from straw retting ground showed higher cellulase activity, specifically the β-glucosidase activity, compared to other contemporary strains. Though A. fumigatus has been known for high cellulase activity, detailed identification and characterization of the cellulase genes from their genome is yet to be done. In this work we have been analyzed the cellulase genes from the genome sequence database of Aspergillus fumigatus (Af293). Genome analysis suggests two cellobiohydrolase, eleven endoglucanase and seventeen β-glucosidase genes present. β-Glucosidase genes belong to either Glycohydro1 (GH1 or Bgl1) or Glycohydro3 (GH3 or Bgl3) family. The sequence similarity suggests that Bgl1 and Bgl3 of A. fumagatus are phylogenetically close to those of A. fisheri and A. oryzae. The modelled structure of the Bgl1 predicts the (β/α)8 barrel type structure with deep and narrow active site, whereas, Bgl3 shows the (α/β)8 barrel and (α/β)6 sandwich structure with shallow and open active site. Docking results suggest that amino acids Glu544, Glu466, Trp408,Trp567,Tyr44,Tyr222,Tyr770,Asp844,Asp537,Asn212,Asn217 of Bgl3 and Asp224,Asn242,Glu440, Glu445, Tyr367, Tyr365,Thr994,Trp435,Trp446 of Bgl1 are involved in the hydrolysis. Binding affinity analyses suggest that Bgl3 and Bgl1 enzymes are more active on the substrates like 4-methylumbelliferyl glycoside (MUG) and p-nitrophenyl-β-D-1, 4-glucopyranoside (pNPG) than on cellobiose. Further docking with glucose suggests that Bgl1 is more glucose tolerant than Bgl3. Analysis of the Aspergillus fumigatus genome may help to identify a β-glucosidase enzyme with better property and the structural information may help to develop an engineered recombinant enzyme.

  11. Contribution of arginase to manganese metabolism of Aspergillus niger.

    Science.gov (United States)

    Keni, Sarita; Punekar, Narayan S

    2016-02-01

    Aspects of manganese metabolism during normal and acidogenic growth of Aspergillus niger were explored. Arginase from this fungus was a Mn[II]-enzyme. The contribution of the arginase protein towards A. niger manganese metabolism was investigated using arginase knockout (D-42) and arginase over-expressing (ΔXCA-29) strains of A. niger NCIM 565. The Mn[II] contents of various mycelial fractions were found in the order: D-42 strain niger mycelia harvested from acidogenic growth media contain substantially less Mn[II] as compared to those from normal growth media. Nevertheless, acidogenic mycelia harbor considerable Mn[II] levels and a functional arginase. Altered levels of mycelial arginase protein did not significantly influence citric acid production. The relevance of arginase to cellular Mn[II] pool and homeostasis was evaluated and the results suggest that arginase regulation could occur via manganese availability.

  12. The mutagenic action of UV-light irradiation on aspergillus terreus in relation to antibacterial activity

    International Nuclear Information System (INIS)

    Ouda, S.M.

    2009-01-01

    Four strains of cellulolytic fungi (i.e Penicillium oxalicum, Aspergillus niger, Aspergillus terreus and Trichoderma longibrachiatum) were tested for the production of cellulolytic enzymes and antibiotic action. these fungi were cultured on Czapek Dox's media with different cellulosic substrates. A. terreus. exhibited the highest cellulolytic activity and the highest level of anti-bacterial activity against Staphylococcus aureus. and Escherichia Coli, Ultraviolet light as a mutagenic treatment for A.terreus was investigated. Two treated isolates U.30.12 and U.60.10 were obtained after the treatment at dose 30 and 60 min., respectively with a higher antibiotic activity in comparison with the wild isolate. A compound of fifteen carbon atom of terrecylic acid was isolated from ethyl acetate extract using spectroscopic analysis

  13. Effect of essential oils on Aspergillus spore germination, growth and mycotoxin production:a potential source of botanical food preservative

    Institute of Scientific and Technical Information of China (English)

    Negero Gemeda; Yimtubezinash Woldeamanuel; Daniel Asrat; Asfaw Debella

    2014-01-01

    Objective: To investigate effect of essential oils on Aspergillus spore germination, growth and mycotoxin production.Method: In vitro antifungal and antiaflatoxigenic activity of essential oils was carried out using poisoned food techniques, spore germination assay, agar dilution assay, and aflatoxin arresting assay on toxigenic strains of Aspergillus species.Results: Cymbopogon martinii, Foeniculum vulgare and Trachyspermum ammi (T. ammi) essential oils were tested against toxicogenic isolates of Aspergillus species. T. ammi oil showed highest antifungal activity. Absolute mycelial inhibition was recorded at 1 µl/mL by essential oils of T. ammi. The oil also showed, complete inhibition of spore germination at a concentration of 2 µl/mL. In addition, T. ammi oil showed significant antiaflatoxigenic potency by totally inhibiting aflatoxin production from Aspergillus niger and Aspergillus flavus at 0.5 and 0.75 µl/mL, respectively. Cymbopogon martinii, Foeniculum vulgare and T. ammi oils as antifungal were found superior over synthetic preservative. Moreover, a concentration of 5 336.297 µl/kg body weight was recorded for LC50 on mice indicating the low mammalian toxicity and strengthening its traditional reputations.Conclusions:In conclusion, the essential oils from T. ammi can be a potential source of safe natural food preservative for food commodities contamination by storage fungi.

  14. Presence of Aspergillus sydowii, a pathogen of gorgonian sea fans in the marine sponge Spongia obscura.

    Science.gov (United States)

    Ein-Gil, Neta; Ilan, Micha; Carmeli, Shmuel; Smith, Garriet W; Pawlik, Joseph R; Yarden, Oded

    2009-06-01

    The fungus Aspergillus sydowii is the causative agent of epidemics that affect gorgonian corals (sea fans) and has significantly affected their populations in the Caribbean Sea. We have isolated a strain of A. sydowii from healthy marine sponges (Spongia obscura) collected in Bahamian inshore waters. After its identification on the basis of morphology, molecular markers and chemical profiling followed by pathogenicity tests, we found this strain to be highly similar to a strain isolated from diseased coral, and have shown the capacity of this fungus to persist in sponge environment. Our findings suggest that sponges have the possibility of being reservoirs of a potential marine pathogen.

  15. Proteomic analysis of Aspergillus niger type strain (MUM 03.01) after accelerated freeze-drying preservation

    OpenAIRE

    Simões, Marta Filipa Jesus Freitas; Santos, Cledir; Rampitsch, Christof; Lima, Nelson

    2013-01-01

    Industrial processes based on biotechnology require a reliable source of microbial cultures, raising a need for the microbial safe long-term storage. The expanding biotechnological applications of Aspergillus niger requires effective long-term preservation that maintains their viability and also their physiological and genetic features [I]. From the best of our knowledge, proteomic analysis for monitoring the effect of preservation techniques on fungai intra- and extracellular ...

  16. Variability of Germinative Potential among Pathogenic Species of Aspergillus

    OpenAIRE

    Araujo, Ricardo; Rodrigues, Acacio Gonçalves

    2004-01-01

    The objective of our study was to evaluate parameters influencing the germination of Aspergillus conidia. Inoculum concentration and age significantly influenced germination. Different incubation temperatures revealed significant differences among Aspergillus species. The internal human milieu provides the ideal conditions for the development of invasive disease by Aspergillus fumigatus but restricts invasion by Aspergillus flavus and Aspergillus niger.

  17. Heterologous Expression of Xylanase II from Aspergillus usamii in Pichia pastoris

    OpenAIRE

    Zhou, Chenyan; Wang, Yongtao; Wu, Minchen; Wang, Wu; Li, Dongfeng

    2009-01-01

    To efficiently produce xylanase for food processing industry, a gene encoding xylanase II (XynII) from Aspergillus usamii has been cloned into the vector pPIC9K and integrated into the genome of Pichia pastoris KM71 by electroporation. By means of minimal dextrose (MD) plates and PCR, the recombinant P. pastoris strains (His+Muts) have been obtained. Activity assay and SDS-PAGE demonstrate that XynII was extracellularly expressed in P. pastoris with the induction of methanol. In shake flask c...

  18. Determination and production of antimicrobial compounds by Aspergillus clavatonanicus strain MJ31, an endophytic fungus from Mirabilis jalapa L. using UPLC-ESI-MS/MS and TD-GC-MS analysis.

    Directory of Open Access Journals (Sweden)

    Vineet Kumar Mishra

    Full Text Available Endophytic fungi associated with medicinal plants are reported as potent producers of diverse classes of secondary metabolites. In the present study, an endophytic fungi, Aspergillus clavatonanicus strain MJ31, exhibiting significant antimicrobial activity was isolated from roots of Mirabilis jalapa L., was identified by sequencing three nuclear genes i.e. internal transcribed spacers ribosomal RNA (ITS rRNA, 28S ribosomal RNA (28S rRNA and translation elongation factor 1- alpha (EF 1α. Ethyl acetate extract of strain MJ31displayed significant antimicrobial potential against Bacillus subtilis, followed by Micrococccus luteus and Staphylococcus aureus with minimum inhibitory concentrations (MIC of 0.078, 0.156 and 0.312 mg/ml respectively. In addition, the strain was evaluated for its ability to synthesize bioactive compounds by the amplification of polyketide synthase (PKS and non ribosomal peptide synthetase (NRPS genes. Further, seven antibiotics (miconazole, ketoconazole, fluconazole, ampicillin, streptomycin, chloramphenicol, and rifampicin were detected and quantified using UPLC-ESI-MS/MS. Additionally, thermal desorption-gas chromatography mass spectrometry (TD-GC-MS analysis of strain MJ31 showed the presence of 28 volatile compounds. This is the first report on A. clavatonanicus as an endophyte obtained from M. jalapa. We conclude that A. clavatonanicus strain MJ31 has prolific antimicrobial potential against both plant and human pathogens and can be exploited for the discovery of new antimicrobial compounds and could be an alternate source for the production of secondary metabolites.

  19. Identity of the xerophilic species Aspergillus penicillioides: Integrated analysis of the genotypic and phenotypic characters.

    Science.gov (United States)

    Tamura, Miki; Kawasaki, Hiroko; Sugiyama, Junta

    1999-02-01

    We examined the identity of Aspergillus penicillioides, the typical xerophilic and strictly anamorphic species, using an integrated analysis of the genotypic and phenotypic characters. Our experimental methods on two genotypic characters, i.e., DNA base composition using the HPLC method and DNA relatedness using the nitrocellulose filter hybridization technique between A. flavus, A. oryzae, and their close relations revealed a good agreement with the values by buoyant density (for DNA base composition) and spectrophotometric determination (for DNA relatedness) reported by Kurtzman et al. in 1986. On the basis of these comparisons, we examined DNA base composition and DNA relatedness of six selected strains of A. penicillioides, including IFO 8155 (originally described as A. vitricola), one strain of A. restrictus, and the respective strains from Eurotium amstelodami, E. repens, and E. rubrum. As a result, five strains within A. penicillioides, including the neotype strain NRRL 4548, had G+C contents of 46 to 49 mol%, whereas IFO 8155 had 50 mol%. A. restrictus had 52 mol%, and three Eurotium species ranged from 46 to 49 mol%. The DNA relatedness between A. penicillioides (five strains), except for IFO 8155, exhibited values greater than 70%, but the DNA complementarity between four strains and IFO 8155 in A. penicillioides revealed values of less than 40%. DNA relatedness values between three species of Eurotium were 65 to 72%. We determined 18S, 5.8S, and ITS rDNA sequences as other genotypic characters from A. penicillioides (six strains), A. restrictus, and related teleomorphic species of Eurotium. In three phylogenetic trees inferred from these sequences, five strains of A. penicillioides, including the neotype strain, were closely related to each other, whereas IFO 8155 was distantly related and grouped with other xerophilic species. Our results have suggested that A. penicillioides typified by NRRL 4548 and A. penicillioides IFO 8155 (ex holotype of A

  20. Genetic analysis of conidiation regulatory pathways in koji-mold Aspergillus oryzae.

    Science.gov (United States)

    Ogawa, Masahiro; Tokuoka, Masafumi; Jin, Feng Jie; Takahashi, Tadashi; Koyama, Yasuji

    2010-01-01

    Conidia of koji-mold Aspergillus oryzae are often used as starters in the fermented food industry. However, little is known about conidiation regulation in A. oryzae. To improve the productivity of conidia in A. oryzae, it is necessary to understand conidiation regulation in the strain. Therefore, we analyzed the conidiation regulatory system in A. oryzae using 10 kinds of conidiation regulatory gene disruptants. The phenotypes of AorfluG, AorflbA, AorflbB, AorflbC, AorflbD, AorflbE, AorbrlA, AorabaA, AorwetA, and AorfadA mutants are almost identical to those of the corresponding mutants in Aspergillus nidulans. The results indicated that the functions of conidiation regulatory genes are almost conserved between A. oryzae and A. nidulans. However, the severely reduced conidiation phenotype of the AorfluG disruptant in A. oryzae differs from the phenotype of the corresponding mutant in Aspergillus fumigatus in air-exposed culture conditions. These results suggest that A. oryzae, A. nidulans, and A. fumigatus have a G-protein signaling pathway and brlA orthologs in common, and only A. fumigatus has particular brlA activation pathways that are independent of the fluG ortholog. Furthermore, the analyses of AorflbA disruptant and AorfadA dominant-active mutants implicated that AorFadA-mediated G-protein signaling suppresses vegetative growth of A. oryzae.

  1. Genotypic regulation of aflatoxin accumulation but not Aspergillus fungal growth upon post-harvest infection of peanut (Arachis hypogaea L.) seeds

    Science.gov (United States)

    Aflatoxin contamination is a major economic and food safety concern for the peanut industry that largely could be mitigated by genetic resistance. To screen peanut for aflatoxin resistance, Ten genotypes were infected with green fluorescent protein (GFP) - expression Aspergillus flavus strain. Per...

  2. Aspergillus baeticus sp. nov. and Aspergillus thesauricus sp. nov., two species in section Usti from Spanish caves.

    Science.gov (United States)

    Nováková, Alena; Hubka, Vit; Saiz-Jimenez, Cesareo; Kolarik, Miroslav

    2012-11-01

    Two novel species of Aspergillus that are clearly distinct from all known species in section Usti were revealed during a study of microfungal communities in Spanish caves. The novel species identified in this study and additional species of Aspergillus section Usti are associated with places and substrates related to human activities in caves. Novel species are described using data from four loci (ITS, benA, caM and rpb2), morphology and basic chemical and physiological analyses. Members of the species Aspergillus thesauricus sp. nov. were isolated from various substrates, including decaying organic matter, cave air and cave sediment of the Cueva del Tesoro Cave (the Treasure cave); the species is represented by twelve isolates and is most closely related to the recently described Aspergillus germanicus. Members of the species Aspergillus baeticus sp. nov. were isolated from cave sediment in the Gruta de las Maravillas Cave (the Grotto of the Marvels); the species is represented by two isolates. An additional isolate was found in the Cueva del Tesoro Cave and in the Demänovská Peace Cave (Slovakia), suggesting a potentially wide distribution of this micro-organism. The species is related to Aspergillus ustus and Aspergillus pseudoustus. Both species were unable to grow at 37 °C, and a weakly positive, light greenish yellow Ehrlich reaction was observed in A. thesauricus. Unique morphological features alone are sufficient to distinguish both species from related taxa.

  3. Biosynthesis of extracellular and intracellular gold nanoparticles by Aspergillus fumigatus and A. flavus.

    Science.gov (United States)

    Gupta, Saurabh; Bector, Shruti

    2013-05-01

    Green chemistry is a boon for the development of safe, stable and ecofriendly nanostructures using biological tools. The present study was carried out to explore the potential of selected fungal strains for biosynthesis of intra- and extracellular gold nanostructures. Out of the seven cultures, two fungal strains (SBS-3 and SBS-7) were selected on the basis of development of dark pink colour in cell free supernatant and fungal beads, respectively indicative of extra- and intracellular gold nanoparticles production. Both biomass associated and cell free gold nanoparticles were characterized using X-ray diffractogram (XRD) analysis and transmission electron microscopy (TEM). XRD analysis confirmed crystalline, face-centered cubic lattice of metallic gold nanoparticles along with average crystallite size. A marginal difference in average crystallite size of extracellular (17.76 nm) and intracellular (26 and 22 nm) Au-nanostructures was observed using Scherrer equation. In TEM, a variety of shapes (triangles, spherical, hexagonal) were observed in both extra- and intracellular nanoparticles. 18S rRNA gene sequence analysis by multiple sequence alignment (BLAST) indicated 99 % homology of SBS-3 to Aspergillus fumigatus with 99 % alignment coverage and 98 % homology of SBS-7 to Aspergillus flavus with 98 % alignment coverage respectively. Native-PAGE and activity staining further confirmed enzyme linked synthesis of gold nanoparticles.

  4. Cloning of the DNA Repair Gene, Uvsf, by Transformation of Aspergillus Nidulans

    OpenAIRE

    Oza, K.; Kafer, E.

    1990-01-01

    As a first step in the cloning of the DNA repair gene uvsF of Aspergillus nidulans, uvsF pyrG double mutant strains were transformed with a genomic library which carried the complementing Neurospora pyr-4 gene in the vector. Rare pyr(+) uvs(+) cotransformants were obtained on media lacking pyrimidines, overlayed with MMS (methyl-methane sulfonate) to which uvsF is hypersensitive. Among MMS-resistant transformants, Southerns revealed two types which showed single bands of different sizes when ...

  5. Comparative Chemistry of Aspergillus oryzae (RIB40) and A. flavus (NRRL 3357)

    OpenAIRE

    Rank, Christian; Klejnstrup, Marie Louise; Petersen, Lene Maj; Kildgaard, Sara; Frisvad, Jens Christian; Gotfredsen, Charlotte Held; Larsen, Thomas Ostenfeld

    2012-01-01

    Aspergillus oryzae and A. flavus are important species in industrial biotechnology and food safety and have been some of the first aspergilli to be fully genome sequenced. Bioinformatic analysis has revealed 99.5% gene homology between the two species pointing towards a large coherence in the secondary metabolite production. In this study we report on the first comparison of secondary metabolite production between the full genome sequenced strains of A. oryzae (RIB40) and A. flavus (NRRL 3357...

  6. Characterization of a polyketide synthase in Aspergillus niger whose product is a precursor for both dihydroxynaphthalene (DHN) melanin and naphtho-γ-pyrone.

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Yi Ming; Meyer, Kristen M; Praseuth, Michael; Baker, Scott E; Bruno, Kenneth S; Wang, Clay C

    2010-12-06

    The genome sequencing of the fungus Aspergillus niger, an industrial workhorse, uncovered a large cache of genes encoding enzymes thought to be involved in the production of secondary metabolites yet to be identified. Identification and structural characterization of many of these predicted secondary metabolites are hampered by their low concentration relative to the known A. niger metabolites such as the naphtho-γ-pyrone family of polyketides. We deleted a nonreducing PKS gene in A. niger strain ATCC 11414, a daughter strain of A. niger ATCC strain 1015 whose genome was sequenced by the DOE Joint Genome Institute. This PKS encoding gene is a predicted ortholog of alb1 from Aspergillus fumigatus which is responsible for production of YWA1, a precursor of fungal DHN melanin. Our results show that the A. niger alb1 PKS is responsible for the production of the polyketide precursor for DHN melanin biosynthesis. Deletion of alb1 elimnates the production of major metabolites, naphtho-γ-pyrones. The generation of an A. niger strain devoid of naphtho-γ-pyrones will greatly facilitate the elucidation of cryptic biosynthetic pathways in this organism.

  7. Improved production of kojic acid by mutagenesis of Aspergillus flavus HAk1 and Aspergillus oryzae HAk2 and their potential antioxidant activity.

    Science.gov (United States)

    Ammar, Hala A M; Ezzat, Saeid M; Houseny, Asmaa M

    2017-10-01

    Two wild-type (WT) Aspergillus strains, A. flavus HAk1 and A. oryzae HAk2, were selected for kojic acid (KA) biosynthesis. Malt extract sucrose culture medium (MES) was the best culture medium for maximum production of KA. The maximum production of KA has been estimated at pH 4 after 7 days of incubation at 30 °C. Overproduction of KA was attained by mutagenesis of both A. flavus HAk1 and A. oryzae HAk2 through their exposer to different doses of gamma irradiation. The mutant strains (MT) A. flavus HAk1-M2 and A. oryzae HAk2-M26 were the most stable mutants for maximum production of KA through four generations. Yield of KA by A. oryzae HAk2-M26 and A. flavus HAk1-M2 has been 2.03-fold and 1.9-fold, respectively, higher than their wild-type strains. All WT and MT strains were used for KA production from different agricultural raw materials. Apple peel was the best waste for KA production by WT strains of A. flavus and A. oryzae, while orange peel and rice stalk are best material for KA production by MT strains, A. flavus HAk1-M2 and A. oryzae HAk2-M26, respectively. All experimental strains have the ability to produce considerable amounts of KA from sugarcane molasse (SCM) and sugar-beet molasse (SBM). SBM was better than SCM for KA production by all strains. The antioxidant activity of biosynthesizing KA was strongly affected with production conditions, where the highest antioxidant activity of all strains was recorded at the optimum environmental and nutritional conditions for KA production.

  8. Heterologous expression of Gaeumannomyces graminis lipoxygenase in Aspergillus nidulans

    NARCIS (Netherlands)

    Heshof, R.; Schayck, van J.P.; Tamayo Ramos, J.A.; Graaff, de L.H.

    2014-01-01

    Aspergillus sp. contain ppo genes coding for Ppo enzymes that produce oxylipins from polyunsaturated fatty acids. These oxylipins function as signal molecules in sporulation and influence the asexual to sexual ratio of Aspergillus sp. Fungi like Aspergillus nidulans and Aspergillus niger contain

  9. Isolation, identification of an axenic fungal isolate of aspergillus sp. (mbl-1511) and its subsequent improvement for enhanced extracellular lipolytic potential through monoculture fermentation

    International Nuclear Information System (INIS)

    Iftikhar, T.; Sidra, A.; Ali, M.; Majeed, H.; Abdullah, R.

    2017-01-01

    The present investigation was conducted for extracellular lipases production. One hundred and forty samples of fungi were isolated from different environment and food samples. Among all the isolated cultures, an isolate obtained from chicken roasted in oil (MBL-1511) gave the highest extracellular lipase through SSF. Hyper producer strain (MBL-1511) was morphologically identified. A morphologically identified isolate of Aspergillus niger (MBL 1511) was verified by DNA barcoding marker like 18S rRNA gene sequence. The sequence of Aspergillus niger (MBL 1511) was registered with accession no. [GenBank: KP172477] in the public nucleotide library (genbank) of NCBI. The selected hyper producer of Aspergillus niger (MBL-1511) strain was subjected to physical and chemical mutagenic treatments to improve its lipolytic potential. Proximate analysis confirmed brassica meal as the best basal substrate with the lipases potential of 10.67+-0.01 IU/mL (wild) and 19.58+-0.04 IU/mL (mutant). The optimum conditions for the maximized extracellular lipases production were 1.0 mL inoculum at 30 degree C after 72 h at pH of 6.2. Finally, a potent mutant of A. niger [MBL-1511SA-4(150 min)] with an increased activity of 161 % over the wild strain was obtained when olive oil was used at 1% (v/v) concentration. (author)

  10. [Survival Strategies of Aspergillus in the Human Body].

    Science.gov (United States)

    Tashiro, Masato; Izumikawa, Koichi

    2017-01-01

     The human body is a hostile environment for Aspergillus species, which originally live outside the human body. There are lots of elimination mechanisms against Aspergillus inhaled into the human body, such as high body temperature, soluble lung components, mucociliary clearance mechanism, or responses of phagocytes. Aspergillus fumigatus, which is the primary causative agent of human infections among the human pathogenic species of Aspergillus, defend itself from the hostile human body environment by various mechanisms, such as thermotolerance, mycotoxin production, and characteristic morphological features. Here we review mechanisms of defense in Aspergillus against elimination from the human body.

  11. Utilization of Aspergillus oryzae to produce pectin lyase from various agro-industrial residues

    OpenAIRE

    Koser, Safia; Anwar, Zahid; Iqbal, Zafar; Anjum, Awais; Aqil, Tahir; Mehmood, Sajid; Irshad, Muhammad

    2014-01-01

    The present study was aimed to investigate the culture influence on pectin lyase production potential of fungal strain Aspergillus oryzae. The enzyme profile of A. oryzae showed highest activity of pectin lyase after 3rd day of incubation on lemon peel waste under solid state fermentation conditions. To induce the pectin lyase synthesis capability of A. oryzae at optimal level various culture variables including physical and nutritional parameters were optimized by adopting classical optimiza...

  12. Production of Fumonisin B-2 and B-4 by Aspergillus niger on Grapes and Raisins

    DEFF Research Database (Denmark)

    Mogensen, Jesper Mølgaard; Frisvad, Jens Christian; Thrane, Ulf

    2010-01-01

    The recent discovery of fumonisin production in Aspergillus niger, raises concerns about the presence of these mycotoxins in grapes and raisins as well as other commodities where A. niger is a frequent contaminant. Here we investigate the potential production of fumonisins in A. niger cultured...... on grapes and raisins. Sixty-six A. niger, 4 A. tubingensis, and 16 A. acidus strains isolated from raisins were tested for fumonisin production on laboratory media. Neither A. tubingensis nor A. acidus strains produced fumonisins, but 77% of A. niger strains did. None of the strains produced ochratoxin A....... Ten selected fumonisin producing A. niger strains were further able to produce fumonisin B2 and fumonisin B4 on grapes in the range 171−7841 μg fumonisin B2/kg and 14−1157 μg fumonisin B4/kg. Four selected strains were able to produce fumonisin B2 (5−6476 μg/kg) and fumonisin B4 (12−672 μg...

  13. Optimization of production of anti-tumor l-asparaginase by free and immobilized marine Aspergillus terreus

    Directory of Open Access Journals (Sweden)

    Aida M. Farag

    2015-12-01

    Full Text Available l-asparaginase plays a vital role in medical application, particularly in treatment of acute lymphoblastic leukemia as an effective anti-tumor agent. In the present study, twenty-one fungal strains were isolated from marine environment of the Red Sea coasts of Egypt. Screening for fungal l-asparaginase production was done, and only five fungal strains were selected and identified as Aspergillus, Penicillium and Fusarium. The most potent fungal isolate was Aspergillus terreus which yielded the highest l-asparaginase specific activity (4.81 U/mg protein. The highest enzyme productivity was observed on the 5th day and the optimized fermentation parameters were pH 6.0, temperature 35 °C. The yield was also high up on using dextrose and asparagine (8.26 U/mg protein as carbon and nitrogen sources. The cultural conditions were studied using the Plackett–Burman experimental design. Immobilization using A. terreus adsorbed on sponge enhanced the enzyme production by 1.33-fold compared to the conventional free-cells. Repeated reuse of the adsorbed cells achieved the maximum enzyme specific activity after three cycles (33.86 U/mg protein.

  14. Formation of sclerotia and production of indoloterpenes by Aspergillus niger and other species in section Nigri.

    Directory of Open Access Journals (Sweden)

    Jens C Frisvad

    Full Text Available Several species in Aspergillus section Nigri have been reported to produce sclerotia on well-known growth media, such as Czapek yeast autolysate (CYA agar, with sclerotia considered to be an important prerequisite for sexual development. However Aspergillus niger sensu stricto has not been reported to produce sclerotia, and is thought to be a purely asexual organism. Here we report, for the first time, the production of sclerotia by certain strains of Aspergillus niger when grown on CYA agar with raisins, or on other fruits or on rice. Up to 11 apolar indoloterpenes of the aflavinine type were detected by liquid chromatography and diode array and mass spectrometric detection where sclerotia were formed, including 10,23-dihydro-24,25-dehydroaflavinine. Sclerotium induction can thus be a way of inducing the production of new secondary metabolites from previously silent gene clusters. Cultivation of other species of the black aspergilli showed that raisins induced sclerotium formation by A. brasiliensis, A. floridensis A. ibericus, A. luchuensis, A. neoniger, A. trinidadensis and A. saccharolyticus for the first time.

  15. Formation of Sclerotia and Production of Indoloterpenes by Aspergillus niger and Other Species in Section Nigri

    Science.gov (United States)

    Frisvad, Jens C.; Petersen, Lene M.; Lyhne, E. Kirstine; Larsen, Thomas O.

    2014-01-01

    Several species in Aspergillus section Nigri have been reported to produce sclerotia on well-known growth media, such as Czapek yeast autolysate (CYA) agar, with sclerotia considered to be an important prerequisite for sexual development. However Aspergillus niger sensu stricto has not been reported to produce sclerotia, and is thought to be a purely asexual organism. Here we report, for the first time, the production of sclerotia by certain strains of Aspergillus niger when grown on CYA agar with raisins, or on other fruits or on rice. Up to 11 apolar indoloterpenes of the aflavinine type were detected by liquid chromatography and diode array and mass spectrometric detection where sclerotia were formed, including 10,23-dihydro-24,25-dehydroaflavinine. Sclerotium induction can thus be a way of inducing the production of new secondary metabolites from previously silent gene clusters. Cultivation of other species of the black aspergilli showed that raisins induced sclerotium formation by A. brasiliensis, A. floridensis A. ibericus, A. luchuensis, A. neoniger, A. trinidadensis and A. saccharolyticus for the first time. PMID:24736731

  16. Characterization of Aspergillus species on Brazil nut from the Brazilian Amazonian region and development of a PCR assay for identification at the genus level

    Science.gov (United States)

    2014-01-01

    Background Brazil nut is a protein-rich extractivist tree crop in the Amazon region. Fungal contamination of shells and kernel material frequently includes the presence of aflatoxigenic Aspergillus species from the section Flavi. Aflatoxins are polyketide secondary metabolites, which are hepatotoxic carcinogens in mammals. The objectives of this study were to identify Aspergillus species occurring on Brazil nut grown in different states in the Brazilian Amazon region and develop a specific PCR method for collective identification of member species of the genus Aspergillus. Results Polyphasic identification of 137 Aspergillus strains isolated from Brazil nut shell material from cooperatives across the Brazilian Amazon states of Acre, Amapá and Amazonas revealed five species, with Aspergillus section Flavi species A. nomius and A. flavus the most abundant. PCR primers ASP_GEN_MTSSU_F1 and ASP_GEN_MTSSU_R1 were designed for the genus Aspergillus, targeting a portion of the mitochondrial small subunit ribosomal RNA gene. Primer specificity was validated through both electronic PCR against target gene sequences at Genbank and in PCR reactions against DNA from Aspergillus species and other fungal genera common on Brazil nut. Collective differentiation of the observed section Flavi species A. flavus, A. nomius and A. tamarii from other Aspergillus species was possible on the basis of RFLP polymorphism. Conclusions Given the abundance of Aspergillus section Flavi species A. nomius and A. flavus observed on Brazil nut, and associated risk of mycotoxin accumulation, simple identification methods for such mycotoxigenic species are of importance for Hazard Analysis Critical Control Point system implementation. The assay for the genus Aspergillus represents progress towards specific PCR identification and detection of mycotoxigenic species. PMID:24885088

  17. First isolation of a novel thermostable antifungal peptide secreted by Aspergillus clavatus.

    Science.gov (United States)

    Skouri-Gargouri, Houda; Gargouri, Ali

    2008-11-01

    A novel antifungal peptide produced by an indigenous fungal strain (VR) of Aspergillus clavatus was purified. The antifungal peptide was enriched in the supernatant after heat treatment at 70 degrees C. The thermostable character was exploited in the first purification step, as purified peptide was obtained after ultrafiltration and reverse phase-HPLC on C18 column application. The purified peptide named "AcAFP" for A. clavatus antifungal peptide, has molecular mass of 5773Da determined by MALDI-ToF spectrometry. The N-terminal sequence showed a notable identity to the limited family of antifungal peptides produced by ascomycetes fungi. The AcAFP activity remains intact even after heat treatment at 100 degrees C for 1h confirming its thermostability. It exhibits a strong inhibitory activity against mycelial growth of several serious human and plant pathogenic fungi: Fusariuym oxysporum, Fusarium solani, Aspergillus niger, Botrytis cinerea, Alternaria solani, whereas AcAFP did not affect yeast and bacterial growth.

  18. Decolorization and detoxification of Synozol red HF-6BN azo dye, by Aspergillus niger and Nigrospora sp

    Directory of Open Access Journals (Sweden)

    Sidra Ilyas

    2013-01-01

    Full Text Available In the present investigation the fungi, Aspergillus niger and Nigrospora sp. were employed for decolorization of Synazol red HF-6BN. Decolorization study showed that Aspergillus niger and Nigrospora sp. were able to decolorize 88% and 96% Synazol red 6BN, respectively, in 24 days. It was also studied that 86% and 90% Synazol red containing of dye effluent was decolorized by Aspergillus niger and Nigrospora sp. after 28 days of incubation at room temperature. A fungal-based protein with relative molecular mass of 70 kDa was partially purified and examined for enzymatic characteristics. The enzyme exhibited highest activity at temperature ranging from 40-50[degree sign]C and at pH=6.0. The enzyme activity was enhanced in the presence of metal cations. High performance liquid chromatography analysis confirmed that these fungal strains are capable to degrade Synazol red dye into metabolites. No zones of inhibition on agar plates and growth of Vigna radiata in the presence of dye extracted sample, indicated that the fungal degraded dye metabolites are nontoxic to beneficial micro-flora and plant growth. Aspergillus niger and Nigrospora sp. have promising potential in color removal from textile wastewater-containing azo dyes.

  19. Screening of mutant strains producing phytase from A. niger by 60Co γ-ray irradiation

    International Nuclear Information System (INIS)

    Yang Pingping; Wang Yan; Tao Wenyi

    2004-01-01

    60 Co γ-ray was used to irradiate Aspergillus niger 447-92 for screening the mutant strain of producing phytase, and the effects of mutation induction were determined and analyzed. A mutant strain A. niger 496-1 with high level of phytase was selected, the phytase properties of A. niger 496-1 were analyzed

  20. Detection of Aflatoxin Producing Aspergillus flavus in Post-harvest Contaminated Vigna ungulculata Seeds

    Directory of Open Access Journals (Sweden)

    Ajay Kumar Gautam

    2014-07-01

    Full Text Available The present study was carried out with a specific objective to study postharvest spoilage of Lobhiya (Vigna unguiculata seeds contaminated with Aspergillus flavus. Infected seeds were collected and cultured on potato dextrose agar (PDA media, at 25±2 °C. Aspergillus flavus isolates were primarily characterized by its morphological and microscopic characteristics. Collected fungal isolates were also screened for their afaltoxigenic nature on preliminary basis and at molecular level. For preliminary screening, 5 mm disc of fungal culture was soaked with few drops of liquid ammonia. Color change from yellow pigment to plum-red with different intensities showed the mycotoxic nature of the fungus. DNA from fungal isolates was isolated and amplified using PCR with aflatoxin specific primers, apa-2, ver-1 and omt-1. Amplicons of 1032 bp, 895 bp and 596 bp were obtained in most of the isolates regardless of primer set used which was useful to differentiate between mycotoxic and nontoxic isolates of A. flavus. The isolation of aflatoxigenic strains of A. flavus during post-harvest period of lobhiya seeds raise a serious concern over the quality of seeds and a threat to heath of consumers. It was concluded that Aspergillus flavus is responsible for postharvest spolilage of Lobhiya (Vigna unguiculata.

  1. Phylogeny, identification and nomenclature of the genus Aspergillus

    Science.gov (United States)

    Samson, R.A.; Visagie, C.M.; Houbraken, J.; Hong, S.-B.; Hubka, V.; Klaassen, C.H.W.; Perrone, G.; Seifert, K.A.; Susca, A.; Tanney, J.B.; Varga, J.; Kocsubé, S.; Szigeti, G.; Yaguchi, T.; Frisvad, J.C.

    2014-01-01

    Aspergillus comprises a diverse group of species based on morphological, physiological and phylogenetic characters, which significantly impact biotechnology, food production, indoor environments and human health. Aspergillus was traditionally associated with nine teleomorph genera, but phylogenetic data suggest that together with genera such as Polypaecilum, Phialosimplex, Dichotomomyces and Cristaspora, Aspergillus forms a monophyletic clade closely related to Penicillium. Changes in the International Code of Nomenclature for algae, fungi and plants resulted in the move to one name per species, meaning that a decision had to be made whether to keep Aspergillus as one big genus or to split it into several smaller genera. The International Commission of Penicillium and Aspergillus decided to keep Aspergillus instead of using smaller genera. In this paper, we present the arguments for this decision. We introduce new combinations for accepted species presently lacking an Aspergillus name and provide an updated accepted species list for the genus, now containing 339 species. To add to the scientific value of the list, we include information about living ex-type culture collection numbers and GenBank accession numbers for available representative ITS, calmodulin, β-tubulin and RPB2 sequences. In addition, we recommend a standard working technique for Aspergillus and propose calmodulin as a secondary identification marker. PMID:25492982

  2. Molecular Tools for the Detection and Deduction of Azole Antifungal Drug Resistance Phenotypes in Aspergillus Species.

    Science.gov (United States)

    Dudakova, Anna; Spiess, Birgit; Tangwattanachuleeporn, Marut; Sasse, Christoph; Buchheidt, Dieter; Weig, Michael; Groß, Uwe; Bader, Oliver

    2017-10-01

    The incidence of azole resistance in Aspergillus species has increased over the past years, most importantly for Aspergillus fumigatus . This is partially attributable to the global spread of only a few resistance alleles through the environment. Secondary resistance is a significant clinical concern, as invasive aspergillosis with drug-susceptible strains is already difficult to treat, and exclusion of azole-based antifungals from prophylaxis or first-line treatment of invasive aspergillosis in high-risk patients would dramatically limit drug choices, thus increasing mortality rates for immunocompromised patients. Management options for invasive aspergillosis caused by azole-resistant A. fumigatus strains were recently reevaluated by an international expert panel, which concluded that drug resistance testing of cultured isolates is highly indicated when antifungal therapy is intended. In geographical regions with a high environmental prevalence of azole-resistant strains, initial therapy should be guided by such analyses. More environmental and clinical screening studies are therefore needed to generate the local epidemiologic data if such measures are to be implemented on a sound basis. Here we propose a first workflow for evaluating isolates from screening studies, and we compile the MIC values correlating with individual amino acid substitutions in the products of cyp51 genes for interpretation of DNA sequencing data, especially in the absence of cultured isolates. Copyright © 2017 American Society for Microbiology.

  3. Comparative performance evaluation of multi-metal resistant fungal strains for simultaneous removal of multiple hazardous metals.

    Science.gov (United States)

    Dey, Priyadarshini; Gola, Deepak; Mishra, Abhishek; Malik, Anushree; Kumar, Peeyush; Singh, Dileep Kumar; Patel, Neelam; von Bergen, Martin; Jehmlich, Nico

    2016-11-15

    In the present study, five fungal strains viz., Aspergillus terreus AML02, Paecilomyces fumosoroseus 4099, Beauveria bassiana 4580, Aspergillus terreus PD-17, Aspergillus fumigatus PD-18, were screened for simultaneous multimetal removal. Highest metal tolerance index for each individual metal viz., Cd, Cr, Cu, Ni, Pb and Zn (500mg/L) was recorded for A. fumigatus for the metals (Cd, 0.72; Cu, 0.72; Pb, 1.02; Zn, 0.94) followed by B. bassiana for the metals (Cd, 0.56; Cu, 0.14; Ni, 0.29; Zn, 0.85). Next, the strains were exposed to multiple metal mixture (Cd, Cr, Cu, Ni, Pb and Zn) of various concentrations (6, 12, 18, 30mg/L). Compared to other strains, B. bassiana and A. fumigatus had higher cube root growth (k) constants indicating their better adaptability to multi metal stress. After 72h, multimetal accumulation potential of B. bassiana (26.94±0.07mg/L) and A. fumigatus (27.59±0.09mg/L) were higher than the other strains at initial multimetal concentration of 30mg/L. However, considering the post treatment concentrations of individual metals in multimetal mixture (at all the tested concentrations), A. fumigatus demonstrated exceptional performance and could bring down the concentrations of Cd, Cu, Ni, Pb and Zn below the threshold level for irrigation prescribed by Food and Agriculture Organization (FAO). Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Degradation of 3-phenoxybenzoic acid by a filamentous fungus Aspergillus oryzae M-4 strain with self-protection transformation.

    Science.gov (United States)

    Zhu, Yuanting; Li, Jianlong; Yao, Kai; Zhao, Nan; Zhou, Kang; Hu, Xinjie; Zou, Likou; Han, Xinfeng; Liu, Aiping; Liu, Shuliang

    2016-11-01

    A novel filamentous fungus M-4 strain was isolated from soy sauce koji and identified as Aspergillus oryzae (Collection number: CGMCC 11645) on the basis of morphological characteristics and internal transcribed spacer sequence. M-4 could degrade 80.62 % of 3-phenoxybenzoic acid (3-PBA; 100 mg L -1 ) within 5 days. 3-PBA degradation occurred in accordance with first-order kinetics. The degradation metabolites of 3-PBA were identified through high-performance liquid chromatography-mass spectrometry (HPLC-MS). Relevant enzymatic activities and substrate utilization were also investigated, which indicated that M-4 could effectively degrade the intermediates of 3-PBA. Base on analysis of these metabolites, a novel biochemical pathway for the degradation of 3-PBA was proposed. There exists a mutual transformation between 3-phenoxy-benzyl alcohol and 3-PBA, which was firstly reported about the degradation of 3-PBA and may be attributed to self-protection transformation of M-4; subsequently, 3-PBA was gradually transformed into phenol, 3-hydroxy-5-phenoxy benzoic acid, protocatechuic acid and gallic acid. The safety of M-4 was evaluated via an acute toxicity test in vivo. The biodegradation ability of M-4 without toxic effects reveals that this fungus may be likely to be used for eliminating 3-PBA from contaminated environment or fermented foods.

  5. Aspergillus saccharolyticus sp. nov., a new black Aspergillus species isolated in Denmark

    DEFF Research Database (Denmark)

    Sørensen, Annette; Lübeck, Peter S.; Lübeck, Mette

    2011-01-01

    A novel species, Aspergillus saccharolyticus sp. nov., belonging to the Aspergillus section Nigri group is described. This species was isolated in Denmark from treated hardwood. Its taxonomic status was determined using a polyphasic taxonomic approach including phenotypic (morphology and extrolite...... profiles) and molecular (β-tubulin, internal transcribed spacer and calmodulin gene sequences, and universally primed PCR fingerprinting) analysis. Phenotypic and molecular data enabled this novel species to be clearly distinguished from other black aspergilli. A. saccharolyticus is a uniseriate...

  6. Mycoremediation of endosulfan and its metabolites in aqueous medium and soil by Botryosphaeria laricina JAS6 and Aspergillus tamarii JAS9.

    Directory of Open Access Journals (Sweden)

    Sivagnanam Silambarasan

    Full Text Available Microbial degradation offers an efficient and ecofriendly approach to remove toxicants from the contaminated environments. Botryosphaeria laricina JAS6 and Aspergillus tamarii JAS9 were capable of degrading endosulfan and their metabolites which were isolated through enrichment technique. Both the strains were able to withstand an exposure of 1300 mg/L and showed luxuriant growth at 1000 mg/L of endosulfan. The change in pH in the culture broth was from 6.8 to 3.4 and 3.8 during growth kinetic studies of JAS6 and JAS9 strains, respectively upon biological degradation of endosulfan. The degradation of endosulfan by JAS6 and JAS9 strains were examined by HPLC. The biodegradation rate constant (k and the initial concentration were reduced by 50% (DT50 which was determined by first and pseudo first order kinetic models. In the present investigation it has been revealed that Botryosphaeria laricina JAS6 and Aspergillus tamarii JAS9 possessing endosulfan degrading capability are being reported for the first time. These findings confirm the degradation of endosulfan by JAS6 and JAS9 strains which were accompanied by significant reduction in the toxicity and could be used as remedial measure in contaminated environments.

  7. Inducer-independent production of pectinases in Aspergillus niger by overexpression of the D-galacturonic acid-responsive transcription factor gaaR.

    Science.gov (United States)

    Alazi, Ebru; Knetsch, Tim; Di Falco, Marcos; Reid, Ian D; Arentshorst, Mark; Visser, Jaap; Tsang, Adrian; Ram, Arthur F J

    2018-03-01

    The transcription factor GaaR is needed for the expression of genes required for pectin degradation and transport and catabolism of the main degradation product, D-galacturonic acid (GA) in Aspergillus niger. In this study, we used the strong constitutive gpdA promoter of Aspergillus nidulans to overexpress gaaR in A. niger. Overexpression of gaaR resulted in an increased transcription of the genes encoding pectinases, (putative) GA transporters, and catabolic pathway enzymes even under non-inducing conditions, i.e., in the absence of GA. Exoproteome analysis of a strain overexpressing gaaR showed that this strain secretes highly elevated levels of pectinases when grown in fructose. The genes encoding exo-polygalacturonases were found to be subjected to CreA-mediated carbon catabolite repression, even in the presence of fructose. Deletion of creA in the strain overexpressing gaaR resulted in a further increase in pectinase production in fructose. We showed that GaaR localizes mainly in the nucleus regardless of the presence of an inducer, and that overexpression of gaaR leads to an increased concentration of GaaR in the nucleus.

  8. Aspergillus niger PA2: a novel strain for extracellular biotransformation of L-tyrosine into L-DOPA.

    Science.gov (United States)

    Agarwal, Pragati; Pareek, Nidhi; Dubey, Swati; Singh, Jyoti; Singh, R P

    2016-05-01

    L-DOPA (3,4-dihydroxyphenyl-L-alanine), an amino acid derivative is the most widely used drug of choice for the treatment of Parkinson's disease and other neurologic injuries. The present study deals with the elevated biochemical transformation of L-tyrosine to L-DOPA by Aspergillus niger PA2, a potent tyrosinase producer, isolated from decomposed food wastes. This appears to be the first report on A. niger as a notable extracellular tyrosinase producer. The extracellular tyrosinase activity produced remarkably higher levels of L-DOPA, i.e. 2.44 mg mL(-1) when the media was supplemented with 5 mg mL(-1) L-tyrosine. The optimum pH for tyrosinase production was 6.0, with the maximal L-DOPA production at the same pH. The product thus produced was analyzed by thin-layer chromatography, UV spectroscopy, high-performance liquid chromatography and Fourier transform infrared spectroscopy, that had denoted this to be L-DOPA. Kinetic parameters viz. Y p/s, Q s and Q p had further indicated the notable levels of production. Thus, Aspergillus niger PA2 could be a promising resource and may be further exploited for large-scale production of L-DOPA.

  9. Antifungal activity of lemon, eucalyptus, thyme, oregano, sage and lavender essential oils against Aspergillus niger and Aspergillus tubingensis isolated from grapes

    Directory of Open Access Journals (Sweden)

    Miroslava Císarová

    2016-01-01

    Full Text Available Today, it is very important to find out the protection of products of natural origin as an alternative to synthetic fungicides. The promising alternative is the use of the essential oils (EOs. Essential oils from plants have great potential as a new source of fungicide to control the pathogenic fungi.The main objective of this study was evaluation of the antifungal activity of lemon (Citrus lemon L., eucalyptus (Eucalyptus globulus LABILL., thyme (Thymus vulgaris L., oregano (Origanum vulgare L. sage (Salvia officinalis L. and lavender (Lavandula angustifolia MILLER. EOs against Aspergillus niger and Aspergillus tubingensis isolated from grapes and their ability to affect the growth. It was tested by using the vapor contact with them. At first both tested isolates were identified by using PCR method. Sequence data of 18S rRNA supported the assignment of these isolates to the genus Aspergillus and species A. niger (ITS region: KT824061; RPB2: KT824060 and A. tubingensis (ITS region: KT824062; RPB2: KT824059. Second, EO antifungal activity was evaluated. The effect of the EO volatile phase was confirmed to inhibit growth of A. niger and A tubingensis. EOs were diluted in DMSO (dimethyl sulfoxide final volume of 100 μL. Only 50 μL this solution was distributed on a round sterile filter paper (1 x 1 cm by micropipette, and the paper was placed in the center of the lid of Petri dishes. Dishes were kept in an inverted position. The essential oils with the most significant activity were determined by method of graded concentration of oils - minimum inhibitory doses (MIDs. The most effective tested EOs were oregano and thyme oils, which totally inhibited growth of tested isolates for all days of incubation at 0.625 μL.cm-3 (in air with MFDs 0.125 μL.cm-3 (in air. Lavender EO was less active aginst tested strains (MIDs 0.313 μL.cm-3. The results showed that the tested EOs had antifungal activity, except lemon and eucalyptus. Sage EO was the only

  10. New species in Aspergillus section Terrei

    DEFF Research Database (Denmark)

    Samson, R. A.; Peterson, S. W.; Frisvad, Jens Christian

    2011-01-01

    . clade including the type isolate of A. niveus (CBS 115.27) constitutes a lineage closely related to A. carneus. Fennellia nivea, the hypothesized teleomorph is not related to this clade. Aspergillus allahabadii, A. niveus var. indicus, and two species originally placed in section Versicolores, A......Section Terrei of Aspergillus was studied using a polyphasic approach including sequence analysis of parts of the beta-tubulin and calmodulin genes and the ITS region, macro- and micromorphological analyses and examination of extrolite profiles to describe three new species in this section. Based....... floccosus, A. terreus var. africanus, A. terreus var. aureus, while Aspergillus hortai is recognised at species level. Aspergillus terreus NRRL 4017 is described as the new species A. pseudoterreus. Also included in section Terrei are some species formerly placed in sections Flavipedes and Versicolores. A...

  11. Expression of exo-inulinase gene from Aspergillus niger 12 in E. coli strain Rosetta-gami B (DE3) and its characterization.

    Science.gov (United States)

    Yedahalli, Shreyas S; Rehmann, Lars; Bassi, Amarjeet

    2016-05-01

    Inulin is a linear carbohydrate polymer of fructose subunits (2-60) with terminal glucose units, produced as carbon storage in selected plants. It cannot directly be taken up by most microorganisms due to its large size, unless prior hydrolysis through inulinase enzymes occurs. The hydrolyzed inulin can be taken up by microbes and/or recovered and used industrially for the production of high fructose syrup, inulo-oligosaccharides, biofuel, and nutraceuticals. Cell-free enzymatic hydrolysis would be desirable for industrial applications, hence the recombinant expression, purification and characterization of an Aspergillus niger derived exo-inulinase was investigated in this study. The eukaroyototic exo-inulinase of Aspergillus niger 12 has been expressed, for the first time, in an E. coli strain [Rosetta-gami B (DE3)]. The molecular weight of recombinant exo-inulinase was estimated to be ∼81 kDa. The values of Km and Vmax of the recombinant exo-inulinase toward inulin were 5.3 ± 1.1 mM and 402.1 ± 53.1 µmol min(-1)  mg(-1) protein, respectively. Towards sucrose the corresponding values were 12.20 ± 1.6 mM and 902.8 ± 40.2 µmol min(-1)  mg(-1) protein towards sucrose. The S/I ratio was 2.24 ± 0.7, which is in the range of native inulinase. The optimum temperature and pH of the recombinant exo-inulinase towards inulin was 55°C and 5.0, while they were 50°C and 5.5 towards sucrose. The recombinant exo-inulinase activity towards inulin was enhanced by Cu(2+) and reduced by Fe(2+) , while its activity towards sucrose was enhanced by Co(2+) and reduced by Zn(2+) . © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:629-637, 2016. © 2016 American Institute of Chemical Engineers.

  12. Ecophysiological characterization of Aspergillus carbonarius, Aspergillus tubingensis and Aspergillus niger isolated from grapes in Spanish vineyards.

    Science.gov (United States)

    García-Cela, E; Crespo-Sempere, A; Ramos, A J; Sanchis, V; Marin, S

    2014-03-03

    The aim of this study was to evaluate the diversity of black aspergilli isolated from berries from different agroclimatic regions of Spain. Growth characterization (in terms of temperature and water activity requirements) of Aspergillus carbonarius, Aspergillus tubingensis and Aspergillus niger was carried out on synthetic grape medium. A. tubingensis and A. niger showed higher maximum temperatures for growth (>45 °C versus 40-42 °C), and lower minimum aw requirements (0.83 aw versus 0.87 aw) than A. carbonarius. No differences in growth boundaries due to their geographical origin were found within A. niger aggregate isolates. Conversely, A. carbonarius isolates from the hotter and drier region grew and produced OTA at lower aw than other isolates. However, little genetic diversity in A. carbonarius was observed for the microsatellites tested and the same sequence of β-tubulin gene was observed; therefore intraspecific variability did not correlate with the geographical origin of the isolates or with their ability to produce OTA. Climatic change prediction points to drier and hotter climatic scenarios where A. tubingensis and A. niger could be even more prevalent over A. carbonarius, since they are better adapted to extreme high temperature and drier conditions. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Notable fibrolytic enzyme production by Aspergillus spp. isolates from the gastrointestinal tract of beef cattle fed in lignified pastures.

    Directory of Open Access Journals (Sweden)

    Flávia Oliveira Abrão

    Full Text Available Fungi have the ability to degrade vegetal cell wall carbohydrates, and their presence in the digestive tract of ruminants can minimize the effects of lignified forage on ruminal fermentation. Here, we evaluated enzyme production by Aspergillus spp. isolates from the digestive tracts of cattle grazed in tropical pastures during the dry season. Filamentous fungi were isolated from rumen and feces by culture in cellulose-based medium. Ninety fungal strains were isolated and identified by rDNA sequence analysis, microculture, or both. Aspergillus terreus was the most frequently isolated species, followed by Aspergillus fumigatus. The isolates were characterized with respect to their cellulolytic, xylanolytic, and lignolytic activity through qualitative evaluation in culture medium containing a specific corresponding carbon source. Carboxymethyl cellulase (CMCase activity was quantified by the reducing sugar method. In the avicel and xilan degradation test, the enzyme activity (EA at 48 h was significantly higher other periods (P < 0.05. Intra- and inter-specific differences in EA were verified, and high levels of phenoloxidases, which are crucial for lignin degradation, were observed in 28.9% of the isolates. Aspergillus terreus showed significantly higher EA for avicelase (3.96 ±1.77 and xylanase (3.13 ±.091 than the other Aspergillus species at 48 h of incubation. Isolates AT13 and AF69 showed the highest CMCase specific activity (54.84 and 33.03 U mg-1 protein, respectively. Selected Aspergillus spp. isolates produced remarkable levels of enzymes involved in vegetal cell wall degradation, suggesting their potential as antimicrobial additives or probiotics in ruminant diets.

  14. The chemical heritage of Aspergillus flavus in A. oryzae RIB 40

    DEFF Research Database (Denmark)

    Rank, Christian; Klejnstrup, Marie Louise; Petersen, Lene Maj

    Aspergillus oryzae is a very important species in biotechnology and has been used for centuries in traditional Asian fermentation. The RIB40 strain is particularly interesting as it was one of the first genome sequenced Aspergilli together with A. flavus, a prominent food and feed contaminant...... capable of producing aflatoxin. These species can be perceived as ecotypes. We have analyzed A. oryzae RIB40 and found that the chemical potential could be enhanced significantly under certain conditions. Delicate analysis of their metabolic profiles allow for chemical insight on the transcription level...

  15. Effect of medium composition on static and cidal activity of amphotericin B, itraconazole, voriconazole, posaconazole and terbinafine against Aspergillus fumigatus: a multicenter study.

    NARCIS (Netherlands)

    Tortorano, A.M.; Danaoui, E.; Meletiadis, J.; Mallie, M.; Viviani, M.A.; Piens, M.A.; Rigoni, A.L.; Bastide, J.M.; Grillot, R.

    2002-01-01

    The effect of the medium composition on the fungistatic (MIC) and fungicidal (MLC) activity of amphotericin B, itraconazole, voriconazole, posaconazole and terbinafine against four Aspergillus fumigatus strains has been investigated by four European laboratories. MICs were determined by broth

  16. Lipase production from a wild (LPF-5) and a mutant (HN1) strain of ...

    African Journals Online (AJOL)

    Lipase production from a wild (LPF-5) and a mutant (HN1) strain of Aspergillus niger. ... Several physical parameters (carbon source, nitrogen source, pH, ... for the development of industrial biotechnology for production of extracellular lipase.

  17. Human T-cell responses to Aspergillus fumigatus : In healthy individuals and patients with Aspergillus-related disease

    NARCIS (Netherlands)

    Jolink, H.

    2017-01-01

    The T-cell mediated immune response to Aspergillus fumigatus was studied in healthy individuals and in several patient groups. In peripheral blood of healthy individuals low frequencies of Aspergillus-specific CD4+ T-cells with a Thelper 1 profile were present. In patients with invasive

  18. The GlaA signal peptide substantially increases the expression and secretion of α-galactosidase in Aspergillus niger.

    Science.gov (United States)

    Xu, Yue; Wang, Yan-Hui; Liu, Tian-Qi; Zhang, Hui; Zhang, He; Li, Jie

    2018-03-31

    α-Galactosidases are widely used in many fields. It is necessary to improve the production of enzymes through microbiological processes. The aim of this study was to construct recombinant Aspergillus niger strains with high α-galactosidase production. Two recombinant A. niger strains were constructed: AB and AGB. The recombinant AB strain contained the α-galactosidase aglB gene from A. niger with its native AglB signal peptide regulated by the glucoamylase promoter. In the AGB recombinant strain, the AglB signal peptide was replaced with the glucoamylase (GlaA) signal peptide. The extracellular maximum α-galactosidase activity of the AGB strain was 215.7 U/ml and that of the AB strain was 9.8 U/mL. The optimal conditions for α-galactosidase were pH 3.5 and 35 °C. The GlaA signal peptide substantially increased the yield of secreted α-galactosidase in A. niger. This recombinant strain holds great potential for industrial applications.

  19. Aspergillus luchuensis, an industrially important black Aspergillus in East Asia.

    Directory of Open Access Journals (Sweden)

    Seung-Beom Hong

    Full Text Available 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-ITS, β-tubulin and calmodulin sequences and these differed from those of the closely related A. niger and A. tubingensis. Morphologically, the three species are not significantly different from each other or from A. niger and A. tubingensis. It is concluded that A. luchuensis, A. kawachii and A. acidus are the same species, and A. luchuensis is selected as the correct name based on priority. Strains of A. awamori which are stored in National Research Institute of Brewing in Japan, represent A. niger (n = 14 and A. luchuensis (n = 6. The neotype of A. awamori (CBS 557.65 =  NRRL 4948 does not originate from awamori fermentation and it is shown to be identical with the unknown taxon Aspergillus welwitschiae. Extrolite analysis of strains of A. luchuensis showed that they do not produce mycotoxins and therefore can be considered safe for food and beverage fermentations. A. luchuensis is also frequently isolated from meju and nuruk in Korea and Puerh tea in China and the species is probably common in the fermentation environment of East Asia. A re-description of A. luchuensis is provided because the incomplete data in the original literature.

  20. Disinfection efficacy of chlorine and peracetic acid alone or in combination against Aspergillus spp. and Candida albicans in drinking water.

    Science.gov (United States)

    Sisti, Maurizio; Brandi, Giorgio; De Santi, Mauro; Rinaldi, Laura; Schiavano, Giuditta F

    2012-03-01

    The aim of the present study was to evaluate the fungicidal activity of chlorine and peracetic acid in drinking water against various pathogenic Aspergillus spp. and Candida albicans strains. A. nidulans exhibited the greatest resistance, requiring 10 ppm of chlorine for 30 min contact time for a complete inactivation. Under the same experimental conditions, peracetic acid was even less fungicidal. In this case, A. niger proved to be the most resistant species (50 ppm for 60 min for complete inactivation). All Aspergillus spp. were insensitive to 10 ppm even with extended exposure (>5 h). The combination of chlorine and peracetic acid against Aspergillus spp. did not show synergistic effects except in the case of A. flavus. Complete growth inhibition of C. albicans was observed after about 3 h contact time with 0.2 ppm. C. albicans was less sensitive to peracetic acid. Hence the concentrations of chlorine that are usually present in drinking water distribution systems are ineffective against several Aspergillus spp. and peracetic acid cannot be considered an alternative to chlorine for disinfecting drinking water. The combination of the two biocides is not very effective in eliminating filamentous fungi at the concentrations permitted for drinking water disinfection.

  1. Aspergillus tracheobronchitis in a mild immunocompromised host.

    Science.gov (United States)

    Cho, Byung Ha; Oh, Youngmin; Kang, Eun Seok; Hong, Yong Joo; Jeong, Hye Won; Lee, Ok-Jun; Chang, You-Jin; Choe, Kang Hyeon; Lee, Ki Man; An, Jin-Young

    2014-11-01

    Aspergillus tracheobronchitis is a form of invasive pulmonary aspergillosis in which the Aspergillus infection is limited predominantly to the tracheobronchial tree. It occurs primarily in severely immunocompromised patients such as lung transplant recipients. Here, we report a case of Aspergillus tracheobronchitis in a 42-year-old man with diabetes mellitus, who presented with intractable cough, lack of expectoration of sputum, and chest discomfort. The patient did not respond to conventional treatment with antibiotics and antitussive agents, and he underwent bronchoscopy that showed multiple, discrete, gelatinous whitish plaques mainly involving the trachea and the left bronchus. On the basis of the bronchoscopic and microbiologic findings, we made the diagnosis of Aspergillus tracheobronchitis and initiated antifungal therapy. He showed gradual improvement in his symptoms and continued taking oral itraconazole for 6 months. Physicians should consider Aspergillus tracheobronchitis as a probable diagnosis in immunocompromised patients presenting with atypical respiratory symptoms and should try to establish a prompt diagnosis.

  2. Correlation of Mycotoxin Fumonisin B2 Production and Presence of the Fumonisin Biosynthetic Gene fum8 in Aspergillus niger from Grape

    Science.gov (United States)

    Fumonisins are mycotoxins associated with cancer and several other serious diseases in humans and animals. Production of the mycotoxins has been reported for over two decades in Fusarium species, but has been reported only recently in strains of Aspergillus niger. In addition, a homologue of the f...

  3. Cellulase activity of a thermophilic Aspergillus fumigatus (fresenius) strain

    Energy Technology Data Exchange (ETDEWEB)

    Vandamme, E J; Logghe, J M; Geeraerts, A M

    1982-10-01

    A thermophilic fungus, isolated from horse manure on Whatman-cellulose CF-11 as sole carbon source was identified as Aspergillus fumigatus. It grew optimally at 45 degrees C and displayed highest cellulase activity at 55 degrees C and pH 5.0 towards a range of soluble and crude insolulble cellulosic substrates. Germination and outgrowth of the spore inoculum in carboxymethylcellulose (CMCellulose) medium was accompanied by high endoglucanase (E.C. 3.2.1.4) activity. The cellulose complex e.g. exo-beta-1,4-glucanase (E.C.3.2.1.-); endo-beta-1,4glucanase (E.C.3.2.1.4.) and beta-glucosidase (E.C.3.2.1.21.) displayed quite different properties depending on whether it was formed on low or highly substituted CMCellulose. Extracellular cellulase formation followed biomass accumulation. Upon prolonged incubation cell lysis occurred which resulted in a further increase in cellulase activity. Ball-milled crude cellulosics, such as newsprint, de-inked newsprint, glossy writing paper, toilet paper and beech sawdust were substantially solubilized with 110 hours of growth. The type of crude cellulosic material greatly influenced the pattern of enzyme production. The enzyme complex formed when A. fumigatus was grown on soluble CMC-4M6F, displayed a different activity spectrum towards crude cellulosics compared with that formed on ball-milled glossy writing paper. The extracellular cellulase of A. fumigatus looks promising for a rapid and substantial solubilisation and saccharification of crude cellulosics. (Refs. 32).

  4. Antibiotic Extraction as a Recent Biocontrol Method for Aspergillus Niger andAspergillus Flavus Fungi in Ancient Egyptian mural paintings

    Science.gov (United States)

    Hemdan, R. Elmitwalli; Fatma, Helmi M.; Rizk, Mohammed A.; Hagrassy, Abeer F.

    Biodeterioration of mural paintings by Aspergillus niger and Aspergillus flavus Fungi has been proved in different mural paintings in Egypt nowadays. Several researches have studied the effect of fungi on mural paintings, the mechanism of interaction and methods of control. But none of these researches gives us the solution without causing a side effect. In this paper, for the first time, a recent treatment by antibiotic "6 penthyl α pyrone phenol" was applied as a successful technique for elimination of Aspergillus niger and Aspergillus flavus. On the other hand, it is favorable for cleaning Surfaces of Murals executed by tembera technique from the fungi metabolism which caused a black pigments on surfaces.

  5. Fungal strains isolated from cork stoppers and the formation of 2,4,6-trichloroanisole involved in the cork taint of wine.

    Science.gov (United States)

    Prak, Sina; Gunata, Ziya; Guiraud, Joseph-Pierre; Schorr-Galindo, Sabine

    2007-05-01

    Cork taint is mainly due to 2,4,6-trichloroanisole (TCA) produced through the activity of undesirable fungal strains. We observed that CFU mould number in TCA-containing stoppers was not quantitatively different to that of the stoppers not containing TCA (ca. 10(5)CFU/g). In contrast more fungi diversity was observed in TCA-containing stoppers. Penicillium spp (Penicillium chrysogenum, Penicillium glabrum), Aspergillus spp (Aspergillus niger and Aspergillus oryzae), Chrysonilia sitophila, Mucor racemosus, Paecilomyces sp. and Trichoderma viride were found in TCA-containing stoppers, while C. sitophila and Penicillium sp. were the main fungi in the stoppers devoid of TCA. Conidia were numerous close to the lenticels and present from the lateral surface through to the centre of the stoppers. Strains of Aspergillus, Mucor, Paecilomyces, Penicillium and Trichoderma isolated from TCA-containing stoppers were able to convert 2,4,6-trichlorophenol (TCP) in TCA in resting cell or growing conditions. The best yields of conversion were obtained by green fungi Paecilomyces sp. and P. chrysogenum, 17% and 20%, respectively. Chysonilia sitophila and Penicillium sp. did not produce TCA from TCP in our conditions.

  6. Preparation of progenin III from total steroidal saponins of Dioscorea nipponica Makino using a crude enzyme from Aspergillus oryzae strain.

    Science.gov (United States)

    Liu, Tingqiang; Yu, Hongshan; Liu, Chunying; Bao, Yongming; Hu, Xiangchun; Wang, Yuanhao; Liu, Bing; Fu, Yaoyao; Tang, Sihui; Jin, Fengxie

    2013-05-01

    Progenin III, one of the most active spirostanol saponins, is a potential candidate for anti-cancer therapy due to its strong antitumor activity and low hemolytic activity. However, the concentration of progenin III is extremely low in natural Dioscorea plants. In this paper, the progenin III production from total steroidal saponins of Dioscorea nipponica Makino was studied using the crude enzyme from Aspergillus oryzae DLFCC-38. The crude enzyme converting total steroidal saponins into progenin III was obtained from the A. oryzae DLFCC-38 culture. For enzyme production, the strain was cultured for 72 h at 30 °C with shaking at 150 rpm in 5 % (w/v) malt extract medium containing 2 % (v/v) extract of D. nipponica as the enzyme inducer. The crude enzyme converted total steroidal saponins into major progenin III with a high yield when the reaction was carried out for 9 h at 50 °C and pH 5.0 with the 20 mg/ml of substrate. In the preparation of progenin III, 117 g of crude progenin III was obtained from 160 g of substrate, and the crude product was purified with silica gel column to obtain 60.3 g progenin III of 93.4 % purity.

  7. Letter to the Editor ‘‘Analyses of Black Aspergillus Species of Peanut and Maize for Ochratoxins and Fumonisins,’’ A Comment on: J. Food Prot. 77(5):805–813 (2014)

    DEFF Research Database (Denmark)

    Nielsen, Kristian Fog; Frisvad, Jens Christian; Logrieco, Antonio F.

    2015-01-01

    In a recent article in Journal of Food Protection, Palencia and co-workers (34) published a survey on black Aspergillus species isolated from maize and peanuts reporting the production of some mycotoxins. An important claim in the article is their strains of Aspergillus niger produce fumonisins B1...... and B3. However, for many reasons, we consider the production of these two fumonisin isomers unlikely....

  8. Allergens/Antigens, toxins and polyketides of important Aspergillus species.

    Science.gov (United States)

    Bhetariya, Preetida J; Madan, Taruna; Basir, Seemi Farhat; Varma, Anupam; Usha, Sarma P

    2011-04-01

    The medical, agricultural and biotechnological importance of the primitive eukaryotic microorganisms, the Fungi was recognized way back in 1920. Among various groups of fungi, the Aspergillus species are studied in great detail using advances in genomics and proteomics to unravel biological and molecular mechanisms in these fungi. Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Aspergillus parasiticus, Aspergillus nidulans and Aspergillus terreus are some of the important species relevant to human, agricultural and biotechnological applications. The potential of Aspergillus species to produce highly diversified complex biomolecules such as multifunctional proteins (allergens, antigens, enzymes) and polyketides is fascinating and demands greater insight into the understanding of these fungal species for application to human health. Recently a regulator gene for secondary metabolites, LaeA has been identified. Gene mining based on LaeA has facilitated new metabolites with antimicrobial activity such as emericellamides and antitumor activity such as terrequinone A from A. nidulans. Immunoproteomic approach was reported for identification of few novel allergens for A. fumigatus. In this context, the review is focused on recent developments in allergens, antigens, structural and functional diversity of the polyketide synthases that produce polyketides of pharmaceutical and biological importance. Possible antifungal drug targets for development of effective antifungal drugs and new strategies for development of molecular diagnostics are considered.

  9. Citric acid production and citrate synthase genes in distinct strains of ...

    African Journals Online (AJOL)

    Citric acid is an important organic acid, multifunctional with a wide array of uses. The objectives of this study were the isolation and selection strains of the genus Aspergillus, investigating the solubilization of phosphate of these isolates, verifying the expression rate of genes involved in the identification of isolates, and ...

  10. Fusarium and Aspergillus mycotoxins contaminating wheat silage for dairy cattle feeding in Uruguay

    Directory of Open Access Journals (Sweden)

    Agustina del Palacio

    Full Text Available Abstract Wheat is one of the most important cultivated cereals in Uruguay for human consumption; however, when harvest yields are low, wheat is usually used in ensiling for animal feeding. Ensiling is a forage preservation method that allows for storage during extended periods of time while maintaining nutritional values comparable to fresh pastures. Silage is vulnerable to contamination by spoilage molds and mycotoxins because ensilage materials are excellent substrates for fungal growth. The aim of the study was to identify the mycobiota composition and occurrence of aflatoxins and DON from wheat silage. A total of 220 samples of wheat were collected from four farms in the southwest region of Uruguay were silage practices are developed. The main fungi isolated were Fusarium (43% and Aspergillus (36%, with Fusarium graminearum sensu lato and Aspergillus section Flavi being the most prevalent species. Aflatoxin concentrations in silo bags ranged from 6.1 to 23.3 µg/kg, whereas DON levels ranged between 3000 µg/kg and 12,400 µg/kg. When evaluating aflatoxigenic capacity, 27.5% of Aspergillus section Flavi strains produced AFB1, 5% AFB2, 10% AFG1 and 17.5% AFG2. All isolates of F. graminearum sensu lato produced DON and 15-AcDON. The results from this study contribute to the knowledge of mycobiota and mycotoxins present in wheat silage.

  11. Screening and Molecular Identification of New Microbial Strains for Production of Enzymes of Biotechnological Interest

    Directory of Open Access Journals (Sweden)

    Imen Ghazala

    Full Text Available ABSTRACT: This research focused on isolation, identification and characterization of new strains of fungi and bacteria, which were able to produce extracellular xylanase, mannanase, pectinase and α-amylase. Fungi isolates were identified on the basis of analyses of 18S gene sequencing and internal transcribed spacer region. The closest phylogenetic neighbors according to 18S gene sequence and ITS region data for the two isolates M1 and SE were Aspergillus fumigatus and Aspergillus sydowii, respectively. I4 was identified as Bacillus mojavensis on the basis of the 16S rRNA gene sequencing and biochemical properties. The enzyme production was evaluated by cultivating the isolated microorganisms in liquid-state bioprocess using wheat bran as carbon source. Two fungi (M1, and SE and one bacterium (I4 strains were found to be xylanase producer, and several were proven to be outstanding producers of microbial xylanase. The strains producing xylanase secreted variable amounts of starch-debranching enzymes and produced low level β-mannan-degrading enzyme systems. The bacterium strain was found to be capable of producing pectinolytic enzymes on wheat bran at high level. Some of the strains have good potential for use as sources of important industrial enzymes.

  12. Inhibition of aflatoxin B production of Aspergillus flavus, isolated from soybean seeds by certain natural plant products.

    Science.gov (United States)

    Krishnamurthy, Y L; Shashikala, J

    2006-11-01

    The inhibitory effect of cowdung fumes, Captan, leaf powder of Withania somnifera, Hyptis suaveolens, Eucalyptus citriodora, peel powder of Citrus sinensis, Citrus medica and Punica granatum, neem cake and pongamia cake and spore suspension of Trichoderma harzianum and Aspergillus niger on aflatoxin B(1) production by toxigenic strain of Aspergillus flavus isolated from soybean seeds was investigated. Soybean seed was treated with different natural products and fungicide captan and was inoculated with toxigenic strain of A. flavus and incubated for different periods. The results showed that all the treatments were effective in controlling aflatoxin B(1) production. Captan, neem cake, spore suspension of T. harzianum, A. niger and combination of both reduced the level of aflatoxin B(1) to a great extent. Leaf powder of W. somnifera, H. suaveolens, peel powder of C. sinensis, C. medica and pongamia cake also controlled the aflatoxin B(1) production. All the natural product treatments applied were significantly effective in inhibiting aflatoxin B(1) production on soybean seeds by A. flavus. These natural plant products may successfully replace chemical fungicides and provide an alternative method to protect soybean and other agricultural commodities from aflatoxin B(1) production by A. flavus.

  13. A Case Report on Aspergillus lentulus Pneumonia

    Directory of Open Access Journals (Sweden)

    Muharrem Cidem

    2013-12-01

    Full Text Available Background: Aspergillus lentulus was described as a new species in 2005 but it was isolated from Turkey for the first time. Case report: A. lentulus was isolated as the cause of pneumonia from a patient who had renal transplantation 4 months ago. The patient received immunosuppressive treatment after transplantation. A. lentulus was isolated from his sputum as an agent in pneumonia developed 4 months after the transplantation. Leukocytes, blastospores, and hyphae were seen in both Gram- and Giemsa-stained smears of the sputum. The isolate was identified by using the Maren A. Klich algorithm and molecular methods and confirmed by the reference laboratory of the CBS Fungal Biodiversity Centre (The Netherlands. In the susceptibility tests of the isolate, minimal inhibitory concentrations for amphotericin B, voriconazole, posaconazole, and caspofungin were found to be 0.5 µg/mL, 0.25 µg/mL, 0.125 µg/mL, and 0.25 µg/mL, respectively. The patient recovered with voriconazole treatment (2x200 mg/day. Conclusion: The use of the molecular tests is important for identification of A. lentulus strains because they are very easily confused with A.fumigatus strains according to phenotypic characteristics.

  14. L-lactic acid production by Aspergillus brasiliensis overexpressing the heterologous ldha gene from Rhizopus oryzae.

    Science.gov (United States)

    Liaud, Nadège; Rosso, Marie-Noëlle; Fabre, Nicolas; Crapart, Sylvaine; Herpoël-Gimbert, Isabelle; Sigoillot, Jean-Claude; Raouche, Sana; Levasseur, Anthony

    2015-05-03

    Lactic acid is the building block of poly-lactic acid (PLA), a biopolymer that could be set to replace petroleum-based plastics. To make lactic acid production cost-effective, the production process should be carried out at low pH, in low-nutrient media, and with a low-cost carbon source. Yeasts have been engineered to produce high levels of lactic acid at low pH from glucose but not from carbohydrate polymers (e.g. cellulose, hemicellulose, starch). Aspergilli are versatile microbial cell factories able to naturally produce large amounts of organic acids at low pH and to metabolize cheap abundant carbon sources such as plant biomass. However, they have never been used for lactic acid production. To investigate the feasibility of lactic acid production with Aspergillus, the NAD-dependent lactate dehydrogenase (LDH) responsible for lactic acid production by Rhizopus oryzae was produced in Aspergillus brasiliensis BRFM103. Among transformants, the best lactic acid producer, A. brasiliensis BRFM1877, integrated 6 ldhA gene copies, and intracellular LDH activity was 9.2 × 10(-2) U/mg. At a final pH of 1.6, lactic acid titer reached 13.1 g/L (conversion yield: 26%, w/w) at 138 h in glucose-ammonium medium. This extreme pH drop was subsequently prevented by switching nitrogen source from ammonium sulfate to Na-nitrate, leading to a final pH of 3 and a lactic acid titer of 17.7 g/L (conversion yield: 47%, w/w) at 90 h of culture. Final titer was further improved to 32.2 g/L of lactic acid (conversion yield: 44%, w/w) by adding 20 g/L glucose to the culture medium at 96 h. This strain was ultimately able to produce lactic acid from xylose, arabinose, starch and xylan. We obtained the first Aspergillus strains able to produce large amounts of lactic acid by inserting recombinant ldhA genes from R. oryzae into a wild-type A. brasiliensis strain. pH regulation failed to significantly increase lactic acid production, but switching nitrogen source and changing culture feed

  15. Surface hydrophobicity of Aspergillus nidulans conidiospores and its role in pellet formation

    DEFF Research Database (Denmark)

    Dynesen, Jens Østergaard; Nielsen, Jens

    2003-01-01

    Formation of pellets by Aspergillus nidulans is primarily due to agglomeration of the fungal conidiospores. Although agglomeration of conidiospores has been known for a long time, its mechanism has not been clearly elucidated. To study the influence of the fungal conidiospore wall hydrophobicity...... on conidiospore agglomeration, pellet formation of an A. nidulans wild type and strains deleted in the conidiospore-wall-associated hydrophobins DewA and RodA was compared at different pH values. From contact angle measurements, RodA was found to be more important for the surface hydrophobicity than Dew...

  16. Two novel aflatoxin-producing Aspergillus species from Argentinean peanuts

    DEFF Research Database (Denmark)

    Pildain, M.B.; Frisvad, Jens Christian; Vaamonde, G.

    2008-01-01

    Two novel species from Aspergillus section Flavi from different species of Arachis (peanuts) in Argentina are described as Aspergillus arachidicola sp. nov. and Aspergillus minisclerotigenes sp. nov. Their novel taxonomic status was determined using a polyphasic taxonomic approach with phenotypic...

  17. Phylogeny, identification and nomenclature of the genus Aspergillus

    DEFF Research Database (Denmark)

    Samson, R.A.; Visagie, C.M.; Houbraken, J.

    2014-01-01

    , meaning that a decision had to be made whether to keep Aspergillus as one big genus or to split it into several smaller genera. The International Commission of Penicillium and Aspergillus decided to keep Aspergillus instead of using smaller genera. In this paper, we present the arguments for this decision...... data suggest that together with genera such as Polypaecilum, Phialosimplex, Dichotomomyces and Cristaspora, Aspergillus forms a monophyletic clade closely related to Penicillium. Changes in the International Code of Nomenclature for algae, fungi and plants resulted in the move to one name per species....... We introduce new combinations for accepted species presently lacking an Aspergillus name and provide an updated accepted species list for the genus, now containing 339 species. To add to the scientific value of the list, we include information about living ex-type culture collection numbers and Gen...

  18. Genetic studies with morphological mutants of Aspergillus niger

    International Nuclear Information System (INIS)

    Roy, Ponty; Das, Arati

    1979-01-01

    Three classes of coloured mutations, viz., fawn, yellow and green, occurred recurrently among the population following UV- and γ-radiation from Co 60 of a wild Aspergillus niger strain 350. Ten mutants were picked up and complementation tests were performed by growing them in pairwise combinations. In two cases, allelic mutants of the same colour were observed. All these mutants were again grown in pairwise crosses with a brown A. niger mutant of different lineage. A poor heterokaryotic growth was, however, observed in one combination which later produced a diploid heterozygous nucleus. It segregated spontaneously to develop a large variety of colonies ranging from haploidy to diploidy including aneuploids. These have been analysed genetically and the possible explanations have been given. (auth.)

  19. Drimane sesquiterpenoids from the Aspergillus oryzae QXPC-4.

    Science.gov (United States)

    Ren, Ren; Chen, Chao-Jun; Hu, Sha-Sha; Ge, Hui-Ming; Zhu, Wen-Yong; Tan, Ren-Xiang; Jiao, Rui-Hua

    2015-03-01

    Three new drimane sesquiterpenoids, astellolides C-E (1-3, resp.), four new drimane sesquiterpenoid p-hydroxybenzoates, astellolides F-I (4-7, resp.), together with two known compounds astellolides A and B (8 and 9, resp.), have been isolated from the liquid culture of Aspergillus oryzae (strain No. QXPC-4). Their structures were established by comprehensive analysis of spectroscopic data. The relative and absolute configurations were determined on the basis of NOESY and CD data, together with single-crystal X-ray diffraction analyses of compounds 1-3. The metabolites were evaluated for their cytotoxic activities, however, no compounds showed a significant cytotoxicity against the tested cell lines at a concentration of 20 μM. Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.

  20. Aflatoxin B1-producing Aspergillus in sun-dried medicinal plant materials

    Directory of Open Access Journals (Sweden)

    Chinaputi, A.

    2001-10-01

    Full Text Available Fifty sun-dried medicinal plants were obtained from fraditional drug stores in Songkhla Province, Thailand, and examined for Aspergillus and aflatoxin B1. 288 isolates of Aspergillus were obtaines by standard blotter plate and 25 species were identified. The most common species were A. niger with 99 isolates, A. Flavus 84 isolates, A. terreus 33 isolates, A. oryzae 25 isolates, A.nidulans (Emericella nidulans 10 isolates, A fumigatus 9 isolates and A. chevalieri (Eurotium chevalieri 8 isolates. The other species[A. alliaceus, A.auricomus, A. carbonarius, A. carneus, A. clavatus, A. fisheri(Sartorya fumigata, A. janus, A. melleus,A. ochraceus, A. phoencis, A. sparsus, A. terricola, A. thomii, A. versicolor, A. wentii and Aspergillus sp.1-3] each had 1-2 siolates. Ofthe 50 different plants examined,9 had no trace of Aspergillus, namely Cinnamomum zeylanicum, Illicium verum, Andrographis paniculate, Carthamus tinctorius, Eugenia caryophyllus, Elettaria cardomomum, Coriandrum sativum, Curcuma longa and Cassia garrettiana. The highest number of species(9 of Aspergillus was found on Rauvolfia serpentina.The ability of Aspergillus to form aflatoxin was determined in coconut milk agar by observing the intensity of blue fluorescence in agar surrounding the colonies under ultraviolet light and the yellow pigment under the colonies. The results showed the production of aflatoxin was limited to the one species, A. flavus, from which 84 isolates produced aflatoxin in 57 isolates(67.8%.Aflatoxin B1. production was confirmed by culturing fluorescencing isolates of A. flavus in coconut nilk broth and detecting by ELISA technique. Aflatoxin B1. showed increasing production after 2 days, stabilizing at 3-4 days, and the decreasing after 5-6 days. Aflatoxin B1. could not be detected from nonfluorescencing isolates.The morphological characteristics of the aflatoxin B1. -producing and non-producing strains of A. flavus were similar under light microscope and

  1. Characterization of Aspergillus species associated with ...

    African Journals Online (AJOL)

    About 82 triphala powder samples were analyzed for the association of different fungi. Results reveal the predominance of Aspergillus as the major genera with six predominant species namely, A. niger, A. flavus, A. fumigatus, A. terreus, A. nidulans and A. amstelodami. Therefore, these six isolated Aspergillus species were ...

  2. A two-dimensional proteome map of the aflatoxigenic fungus Aspergillus flavus.

    Science.gov (United States)

    Pechanova, Olga; Pechan, Tibor; Rodriguez, Jose M; Williams, W Paul; Brown, Ashli E

    2013-05-01

    The filamentous fungus Aspergillus flavus is an opportunistic soil-borne pathogen that produces aflatoxins, the most potent naturally occurring carcinogenic compounds known. This work represents the first gel-based profiling analysis of A. flavus proteome and establishes a 2D proteome map. Using 2DE and MALDI-TOF-MS/MS, we identified 538 mycelial proteins of the aflatoxigenic strain NRRL 3357, the majority of which were functionally annotated as related to various cellular metabolic and biosynthetic processes. Additionally, a few enzymes from the aflatoxin synthesis pathway were also identified. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Change in hyphal morphology of Aspergillus Oryzae during fed-batch cultivation

    DEFF Research Database (Denmark)

    Haack, Martin Brian; Olsson, Lisbeth; Hansen, K

    2006-01-01

    the batch phase from 2.8-2.9 up to 4.0-4.4 mu m. The diameter of the hyphal elements remained constant, around 4 mu m, after the feed was started. However, the diameter of the immediate hyphal tip, where the enzyme secretion is thought to take place, increased dramatically with up to a factor 2.5 during......Industrial enzymes are often produced by filamentous fungi in fed-batch cultivations. During cultivation, the different morphological forms displayed by the fungi have an impact on the overall production. The morphology of a recombinant lipase producing Aspergillus oryzae strain was investigated...

  4. SECONDARY METABOLITE FROM ENDOPHYTIC FUNGI Aspergillus niger OF THE STEM BARK OF KANDIS GAJAH (Garcinia griffithii

    Directory of Open Access Journals (Sweden)

    Elfita Elfita

    2012-06-01

    Full Text Available Garcinia griffithii are known as kandis gajah including the Garcinia genus. This plant has been traditionally used by local communities Sarasah Bonta, Lembah Arau, West Sumatra, to treat various diseases including gout. Aspergillus niger was isolated from the tissues of the stem bark of Garcinia griffithii. The fungi strain was identified base on colony and cell morphology characteristic. Aspergillus niger cultured in media 5L Potatos Dextose Broth (PDB for 8 weeks and filtered. Media that already contains secondary metabolites are partitioned using ethyl acetate solvent in 5 L (twice, followed by evaporation. Furthermore, the extract is separated by chromatographic techniques to obtain a pure compound of white crystal. The molecular structures of isolated compounds are determined by spectroscopic methods including IR, 1H-NMR, 13C-NMR, HMQC, HMBC, and COSY. The compound was determined as phenolic (1.

  5. Production of amylases by Aspergillus tamarii

    Directory of Open Access Journals (Sweden)

    Moreira Fabiana Guillen

    1999-01-01

    Full Text Available A strain of Aspergillus tamarii, a filamentous fungus isolated from soil, was able to produce both a-amylase and glucoamylase activities in mineral media supplemented with 1% (w/v starch or maltose as the carbon source. Static cultivation led to significantly higher yields than those obtained using shaking culture. The production of amylases was tolerant to a wide range of initial culture pH values (from 4 to 10 and temperature (from 25 to 42oC. Two amylases, one a-amylase and one glucoamylase, were separated by ion exchange chromatography. Both partially purified enzymes had optimal activities at pH values between 4.5 and 6.0 and were stable under acid conditions (pH 4.0-7.0. The enzymes exhibited optimal activities at temperatures between 50o and 60o C and were stable for more than ten hours at 55oC.

  6. Thermal Characterization of Purified Glucose Oxidase from A Newly Isolated Aspergillus Niger UAF-1

    Science.gov (United States)

    Anjum Zia, Muhammad; Khalil-ur-Rahman; K. Saeed, Muhammad; Andaleeb, Fozia; I. Rajoka, Muhammad; A. Sheikh, Munir; A. Khan, Iftikhar; I. Khan, Azeem

    2007-01-01

    An intracellular glucose oxidase was isolated from the mycelium extract of a locally isolated strain of Aspergillus niger UAF-1. The enzyme was purified to a yield of 28.43% and specific activity of 135 U mg−1 through ammonium sulfate precipitation, anion exchange and gel filtration chromatography. The enzyme showed high affinity for D-glucose with a Km value of 2.56 mM. The enzyme exhibited optimum catalytic activity at pH 5.5. Temperature optimum for glucose oxidase, catalyzed D-glucose oxidation was 40°C. The enzyme showed a high thermostability having a half-life 30 min, enthalpy of denaturation 99.66 kJ mol−1 and free energy of denaturation 103.63 kJ mol−1. These characteristics suggest the use of glucose oxidase from Aspergillus niger UAF-1 as an analytical reagent and in the design of biosensors for clinical, biochemical and diagnostic assays. PMID:18193107

  7. Aspergillus pragensis sp nov discovered during molecular reidentification of clinical isolates belonging to Aspergillus section Candidi

    Czech Academy of Sciences Publication Activity Database

    Hubka, Vít; Lysková, P.; Frisvad, J.C.; Peterson, S.W.; Skořepová, M.; Kolařík, Miroslav

    2014-01-01

    Roč. 52, č. 6 (2014), s. 565-576 ISSN 1369-3786 R&D Projects: GA MŠk(CZ) EE2.3.20.0055; GA MŠk(CZ) EE2.3.30.0003 Institutional support: RVO:61388971 Keywords : Aspergillus candidus * Aspergillus tritici * antifungal susceptibility testing Subject RIV: EE - Microbiology, Virology Impact factor: 2.335, year: 2014

  8. Characterization and biological treatment of colored textile wastewaters from the typical Tunisian hat Chechia dyeing using newly isolated Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Hajer Barouni

    2016-09-01

    Full Text Available This study aimed to characterize and investigate, for the first time, the treatment of real colored wastewaters from the artisanal dyeing of the typical Tunisian hat Chechia, using a newly isolated fungal strain. This textile effluent was a mixture called Mix of colored wastewaters from the three main types of Chechia. The major pollutant of the Mix was the toxic Azo dye Amaranth Acid or Acid Red 27. The fungal strain that made the cleanup was discovered in a Chechia dyeing wastewater’s container and identified by ITS rDNA gene sequencing. This isolated Aspergillus niger showed interesting performances on the demonstration of Chechia wastewater’s biodegradation in batch cultures. In order to understand the effect of agitation, Mix dilution and inoculum size on decolourisation and pollution removal, a full factorial experimental design 23 was set up. At the optimal conditions which were 20% inoculum size, 25% Chechia Mix dilution and an agitation of 100 rpm, Aspergillus niger was able to remove color as high as 70.18±2.84% at an initial dye concentration of 1346.6±0.01 mg/L, and to reduce COD to 74.17±14.52% at an initial COD of 4157±422 mg/L. FT-IR spectra analysis confirmed the decolourisation by biodegradation and transformation of the dyes. The treatment by the isolated Aspergillus niger could be successfully applied as a sustainable method to solve one of handicraft dyeing plants environmental management issues.

  9. Cellulase Production from Spent Lignocellulose Hydrolysates by Recombinant Aspergillus niger▿

    Science.gov (United States)

    Alriksson, Björn; Rose, Shaunita H.; van Zyl, Willem H.; Sjöde, Anders; Nilvebrant, Nils-Olof; Jönsson, Leif J.

    2009-01-01

    A recombinant Aspergillus niger strain expressing the Hypocrea jecorina endoglucanase Cel7B was grown on spent hydrolysates (stillage) from sugarcane bagasse and spruce wood. The spent hydrolysates served as excellent growth media for the Cel7B-producing strain, A. niger D15[egI], which displayed higher endoglucanase activities in the spent hydrolysates than in standard medium with a comparable monosaccharide content (e.g., 2,100 nkat/ml in spent bagasse hydrolysate compared to 480 nkat/ml in standard glucose-based medium). In addition, A. niger D15[egI] was also able to consume or convert other lignocellulose-derived compounds, such as acetic acid, furan aldehydes, and phenolic compounds, which are recognized as inhibitors of yeast during ethanolic fermentation. The results indicate that enzymes can be produced from the stillage stream as a high-value coproduct in second-generation bioethanol plants in a way that also facilitates recirculation of process water. PMID:19251882

  10. Exploitation of Aspergillus terreus for the Production of Natural Statins

    Directory of Open Access Journals (Sweden)

    Mishal Subhan

    2016-04-01

    Full Text Available The fungus Aspergillus (A. terreus has dominated the biological production of the “blockbuster” drugs known as statins. The statins are a class of drugs that inhibit HMG-CoA reductase and lead to lower cholesterol production. The statins were initially discovered in fungi and for many years fungi were the sole source for the statins. At present, novel chemically synthesised statins are produced as inspired by the naturally occurring statin molecules. The isolation of the natural statins, compactin, mevastatin and lovastatin from A. terreus represents one of the great achievements of industrial microbiology. Here we review the discovery of statins, along with strategies that have been applied to scale up their production by A. terreus strains. The strategies encompass many of the techniques available in industrial microbiology and include the optimization of media and fermentation conditions, the improvement of strains through classical mutagenesis, induced genetic manipulation and the use of statistical design.

  11. Molecular epidemiology of Aspergillus collected from cystic fibrosis patients.

    Science.gov (United States)

    Sabino, Raquel; Ferreira, Jose A G; Moss, Richard B; Valente, Joana; Veríssimo, Cristina; Carolino, Elisabete; Clemons, Karl V; Everson, Cassie; Banaei, Niaz; Penner, John; Stevens, David A

    2015-07-01

    Aspergillus respiratory infection is a common complication in cystic fibrosis (CF) and is associated with loss of pulmonary function and allergic disease. Fifty-three Aspergillus isolates recovered from CF patients were identified to species by Internal Transcribed Spacer Region (ITS), β-tubulin, and calmodulin sequencing. Three species complexes (Terrei, Nigri, and Fumigati) were found. Identification to species level gave a single Aspergillus terreus sensu stricto, one Aspergillus niger sensu stricto and 51 Aspergillus fumigatus sensu stricto isolates. No cryptic species were found. To our knowledge, this is the first prospective study of Aspergillus species in CF using molecular methods. The paucity of non-A. fumigatus and of cryptic species of A. fumigatus suggests a special association of A. fumigatus sensu stricto with CF airways, indicating it likely displays unique characteristics making it suitable for chronic residence in that milieu. These findings could refine an epidemiologic and therapeutic approach geared to this pathogen. Copyright © 2014 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

  12. Biotransformation of two furanocoumarins by the fungi species Aspergillus sp. PTCC 5266 and Aspergillus niger PTCC 5010.

    Science.gov (United States)

    Ghasemi, Saba; Habibi, Zohreh; Mohajeri, Maryam; Yousefi, Maryam

    2018-02-22

    The microbial transformations of peucedanin and oreoselon by the fungi Aspergillus niger and Aspergillus sp. were investigated for the first time. Incubation of peucedanin with A. niger yielded a new hydroxylated metabolite with high yield (56%), which was characterized as 2-(1-hydroxypropan-2-yl)-3-methoxy-7H-furo[3,2-g]chromen-7-one. Oreoselon was converted to a new reduced metabolite methyl 3-(2,3-dihydro-6-hydroxy-2-isopropyl-3-oxobenzofuran-5-yl)propanoate in biotransformation by Aspergillus sp. The structures of the metabolites were determined by spectroscopic methods including IR, EI-MS, 1 H NMR, 13 C NMR, and elemental analysis.

  13. Comparative proteomic analyses reveal that FlbA down-regulates gliT expression and SOD activity in Aspergillus fumigatus.

    Science.gov (United States)

    Shin, Kwang-Soo; Park, Hee-Soo; Kim, Young-Hwan; Yu, Jae-Hyuk

    2013-07-11

    FlbA is a regulator of G-protein signaling protein that plays a central role in attenuating heterotrimeric G-protein mediated vegetative growth signaling in Aspergillus. The deletion of flbA (∆flbA) in the opportunistic human pathogen Aspergillus fumigatus results in accelerated cell death and autolysis in submerged culture. To further investigate the effects of ∆flbA on intracellular protein levels we carried out 2-D proteome analyses of 2-day old submerged cultures of ∆flbA and wild type (WT) strains and observed 160 differentially expressed proteins. Via nano-LC-ESI-MS/MS analyses, we revealed the identity of 10 and 2 proteins exhibiting high and low level accumulation, respectively, in ∆flbA strain. Notably, the GliT protein is accumulated at about 1800-fold higher levels in ∆flbA than WT. Moreover, GliT is secreted at high levels from ∆flbA strain, whereas Sod1 (superoxide dismutase) is secreted at a higher level in WT. Northern blot analyses reveal that ∆flbA results in elevated accumulation of gliT mRNA. Consequently, ∆flbA strain exhibits enhanced tolerance to gliotoxin toxicity. Finally, ∆flbA strain displayed enhanced SOD activity and elevated resistance to menadione and paraquat. In summary, FlbA-mediated signaling control negatively affects cellular responses associated with detoxification of reactive oxygen species and of exogenous gliotoxin in A. fumigatus. Regulator of G protein Signaling (RGS) proteins play crucial roles in fundamental biological processes in filamentous fungi. FlbA is the first studied filamentous fungal RGS protein, yet much remains to be understood about its roles in the opportunistic human pathogen Aspergillus fumigatus. In the present study, we examined the effects of the deletion of flbA using comprehensive analyses of the intra- and extracellular proteomes of A. fumigatus wild type and the flbA deletion mutant. Via MS analyses, we identified 10 proteins exhibiting high level accumulation in the flbA deletion

  14. Deletion of admB gene encoding a fungal ADAM affects cell wall construction in Aspergillus oryzae.

    Science.gov (United States)

    Kobayashi, Takuji; Maeda, Hiroshi; Takeuchi, Michio; Yamagata, Youhei

    2017-05-01

    Mammals possess a unique signaling system based on the proteolytic mechanism of a disintegrin and metalloproteinases (ADAMs) on the cell surface. We found two genes encoding ADAMs in Aspergillus oryzae and named them admA and admB. We produced admA and admB deletion strains to elucidate their biological function and clarify whether fungal ADAMs play a similar role as in mammals. The ∆admA∆admB and ∆admB strains were sensitive to cell wall-perturbing agents, congo red, and calcofluor white. Moreover, the two strains showed significantly increased weights of total alkali-soluble fractions from the mycelial cell wall compared to the control strain. Furthermore, ∆admB showed MpkA phosphorylation at lower concentration of congo red stimulation than the control strain. However, the MpkA phosphorylation level was not different between ∆admB and the control strain without the stimulation. The results indicated that A. oryzae AdmB involved in the cell wall integrity without going through the MpkA pathway.

  15. Kinetics Studies on citric acid production by gamma ray induced mutant of Aspergillus niger

    International Nuclear Information System (INIS)

    Begum, A.A.; Choudhury, N.; Islam, M.S.

    1991-01-01

    Effect of cultural pH and incubation temperature on citric acid yield and kinetic patterns of citric acid fermentation by a natural isolate of aspergillus niger as CA16 and one of its gamma ray induced mutants were studied using cane molasses as growth and fermentation substrate. Mutant strain, 277/30 gave maximum citric acid yield of 85 g/l at pH 3.5 and 28 degree centigrade in molasses medium adjusted to 16% sugar and 25% prescott salt in the medium. Parent strain, CA16 gave a maximum yield of 34 g/l at pH 4.0 and 26 degree centigrade in molasses medium adjusted to 16% sugar and 100% prescott salt in the medium. In kinetic studies, strains showed combination kinetics of citric acid fermentation where product formation is directly related to growth and cell mass and indirectly related to carbohydrate uptake

  16. Secondary metabolites from Eurotium species, Aspergillus calidoustus and A. insuetus common in Canadian homes with a review of their chemistry and biological activities

    DEFF Research Database (Denmark)

    Slack, G. J.; Puniani, E.; Frisvad, Jens Christian

    2009-01-01

    As part of studies of metabolites from fungi common in the built environment in Canadian homes, we investigated metabolites from strains of three Eurotium species, namely E. herbariorum, E. amstelodami, and E. rubrum as well as a number of isolates provisionally identified as Aspergillus ustus. T...

  17. Secondary metabolites from Eurotium species, Aspergillus calidoustus and A. insuetus common in Canadian homes with a review of their chemistry and biological activities

    NARCIS (Netherlands)

    Slack, G.J.; Puniani, E.; Frisvad, J.C.; Samson, R.A.; Miller, J.D.

    2009-01-01

    As part of studies of metabolites from fungi common in the built environment in Canadian homes, we investigated metabolites from strains of three Eurotium species, namely E. herbariorum, E. amstelodami, and E. rubrum as well as a number of isolates provisionally identified as Aspergillus ustus. The

  18. Proteomic analysis of temperature dependent extracellular proteins from Aspergillus fumigatus grown under solid-state culture condition.

    Science.gov (United States)

    Adav, Sunil S; Ravindran, Anita; Sze, Siu Kwan

    2013-06-07

    Fungal species of the genus Aspergillus are filamentous ubiquitous saprophytes that play a major role in lignocellulosic biomass recycling and also are considered as cell factories for the production of organic acids, pharmaceuticals, and industrially important enzymes. Analysis of extracellular secreted biomass degrading enzymes using complex lignocellulosic biomass as a substrate by solid-state fermentation could be a more practical approach to evaluate application of the enzymes for lignocellulosic biorefinery. This study isolated a fungal strain from compost, identified as Aspergillus fumigatus, and further analyzed it for lignocellulolytic enzymes at different temperatures using label free quantitative proteomics. The profile of secretome composition discovered cellulases, hemicellulases, lignin degrading proteins, peptidases and proteases, and transport and hypothetical proteins; while protein abundances and further their hierarchical clustering analysis revealed temperature dependent expression of these enzymes during solid-state fermentation of sawdust. The enzyme activities and protein abundances as determined by exponentially modified protein abundance index (emPAI) indicated the maximum activities at the range of 40-50 °C, demonstrating the thermophilic nature of the isolate A. fumigatus LF9. Characterization of the thermostability of secretome suggested the potential of the isolated fungal strain in the production of thermophilic biomass degrading enzymes for industrial application.

  19. Utilization of AFLP markers for PCR-based identification of Aspergillus carbonarius and indication of its presence in green coffee samples.

    Science.gov (United States)

    Schmidt, H; Taniwaki, M H; Vogel, R F; Niessen, L

    2004-01-01

    The objective of this work was to test whether ochratoxin A (OTA) production of Aspergillus niger and A. carbonarius is linked to a certain genotype and to identify marker sequences with diagnostic value aiding identification of A. carbonarius, a fungus of major concern regarding OTA production in food and food raw materials. Aspergillus niger and A. carbonarius were isolated mainly from Brazilian coffee sources. The ability of isolates to produce OTA was tested by thin layer chromatography (TLC). Strains were genetically characterized by AFLP fingerprinting and compared with each other and with reference strains. Cluster analysis of fingerprints showed clear separation of A. niger from A. carbonarius strains. To obtain marker sequences, AFLP fragments were isolated from silver stained polyacrylamide gels, cloned and sequenced. Sequences obtained were used to develop species- specific PCR primers for the identification of A. carbonarius in pure culture and in artificially and naturally infected samples of green coffee. No clear correlation between genetic similarity of the strains studied and their potential to produce OTA was found. The PCR assays designed are a useful and specific tool for identification and highly sensitive detection of A. carbonarius. The developed PCR assays allow specific and sensitive detection and identification of A. carbonarius, a fungus considered to be one of the major causative agents for OTA in coffee and grape-derived products. Assays may provide powerful tools to improve quality control and consumer safety in the food processing industry.

  20. Genomic Diversity in the Genus of Aspergillus

    DEFF Research Database (Denmark)

    Rasmussen, Jane Lind Nybo

    , sections and genus of Aspergillus. The work uncovers a large genomic diversity across all studied groups of species. The genomic diversity was especially evident on the section level, where the proteins shared by all species only represents ⇠55% of the proteome. This number decreases even further, to 38......, sections Nigri, Usti and Cavericolus, clade Tubingensis, and species A. niger. It lastly uses these results to predict genetic traits that take part in fungal speciation. Within a few years the Aspergillus whole-genus sequencing project will have published all currently-accepted Aspergillus genomes......Aspergillus is a highly important genus of saprotrophic filamentous fungi. It is a very diverse genus that is inextricably intertwined with human a↵airs on a daily basis, holding species relevant to plant and human pathology, enzyme and bulk chemistry production, food and beverage biotechnology...

  1. Secretome analysis of Aspergillus fumigatus reveals Asp-hemolysin as a major secreted protein.

    Science.gov (United States)

    Wartenberg, Dirk; Lapp, Katrin; Jacobsen, Ilse D; Dahse, Hans-Martin; Kniemeyer, Olaf; Heinekamp, Thorsten; Brakhage, Axel A

    2011-11-01

    Surface-associated and secreted proteins represent primarily exposed components of Aspergillus fumigatus during host infection. Several secreted proteins are known to be involved in defense mechanisms or immune evasion, thus, probably contributing to pathogenicity. Furthermore, several secreted antigens were identified as possible biomarkers for the verification of diseases caused by Aspergillus species. Nevertheless, there is only limited knowledge about the composition of the secretome and about molecular functions of particular proteins. To identify secreted proteins potentially essential for virulence, the core secretome of A. fumigatus grown in minimal medium was determined. Two-dimensional gel electrophoretic separation and subsequent MALDI-TOF-MS/MS analyses resulted in the identification of 64 different proteins. Additionally, secretome analyses of A. fumigatus utilizing elastin, collagen or keratin as main carbon and nitrogen source were performed. Thereby, the alkaline serine protease Alp1 was identified as the most abundant protein and hence presumably represents an important protease during host infection. Interestingly, the Asp-hemolysin (Asp-HS), which belongs to the protein family of aegerolysins and which was often suggested to be involved in fungal virulence, was present in the secretome under all growth conditions tested. In addition, a second, non-secreted protein with an aegerolysin domain annotated as Asp-hemolysin-like (HS-like) protein can be found to be encoded in the genome of A. fumigatus. Generation and analysis of Asp-HS and HS-like deletion strains revealed no differences in phenotype compared to the corresponding wild-type strain. Furthermore, hemolysis and cytotoxicity was not altered in both single-deletion and double-deletion mutants lacking both aegerolysin genes. All mutant strains showed no attenuation in virulence in a mouse infection model for invasive pulmonary aspergillosis. Overall, this study provides a comprehensive

  2. Aspergillus oryzae-based cell factory for direct kojic acid production from cellulose.

    Science.gov (United States)

    Yamada, Ryosuke; Yoshie, Toshihide; Wakai, Satoshi; Asai-Nakashima, Nanami; Okazaki, Fumiyoshi; Ogino, Chiaki; Hisada, Hiromoto; Tsutsumi, Hiroko; Hata, Yoji; Kondo, Akihiko

    2014-05-18

    Kojic acid (5-Hydroxy-2-(hydroxymethyl)-4-pyrone) is one of the major secondary metabolites in Aspergillus oryzae. It is widely used in food, pharmaceuticals, and cosmetics. The production cost, however, is too high for its use in many applications. Thus, an efficient and cost-effective kojic acid production process would be valuable. However, little is known about the complete set of genes for kojic acid production. Currently, kojic acid is produced from glucose. The efficient production of kojic acid using cellulose as an inexpensive substrate would help establish cost-effective kojic acid production. A kojic acid transcription factor gene over-expressing the A. oryzae strain was constructed. Three genes related to kojic acid production in this strain were transcribed in higher amounts than those found in the wild-type strain. This strain produced 26.4 g/L kojic acid from 80 g/L glucose. Furthermore, this strain was transformed with plasmid harboring 3 cellulase genes. The resultant A. oryzae strain successfully produced 0.18 g/L of kojic acid in 6 days of fermentation from the phosphoric acid swollen cellulose. Kojic acid was produced directly from cellulose material using genetically engineered A. oryzae. Because A. oryzae has efficient protein secretion ability and secondary metabolite productivity, an A. oryzae-based cell factory could be a platform for the production of various kinds of bio-based chemicals.

  3. Growth and hydrolase profiles can be used as characteristics to distinguish Aspergillus niger and other black aspergilli

    Science.gov (United States)

    Meijer, M.; Houbraken, J.A.M.P.; Dalhuijsen, S.; Samson, R.A.; de Vries, R.P.

    2011-01-01

    Wild type Aspergillus niger isolates from different biotopes from all over the world were compared to each other and to the type strains of other black Aspergillus species with respect to growth and extracellular enzyme profiles. The origin of the A. niger isolate did not result in differences in growth profile with respect to monomeric or polymeric carbon sources. Differences were observed in the growth rate of the A. niger isolates, but these were observed on all carbon sources and not specific for a particular carbon source. In contrast, carbon source specific differences were observed between the different species. Aspergillus brasiliensis is the only species able to grow on D-galactose, and A. aculeatus had significantly better growth on Locus Bean gum than the other species. Only small differences were found in the extracellular enzyme profile of the A. niger isolates during growth on wheat bran, while large differences were observed in the profiles of the different black aspergilli. In addition, differences were observed in temperature profiles between the black Aspergillus species, but not between the A. niger isolates, demonstrating no isolate-specific adaptations to the environment. These data indicate that the local environment does not result in stable adaptations of A. niger with respect to growth profile or enzyme production, but that the potential is maintained irrespective of the environmental parameters. It also demonstrates that growth, extracellular protein and temperature profiles can be used for species identification within the group of black aspergilli. PMID:21892240

  4. GROWTH AND ENZYME PRODUCTION DURING CONTINUOUS CULTURES OF A HIGH AMYLASE-PRODUCING VARIANT OF Aspergillus Oryzae

    OpenAIRE

    Zangirolami,T.C.; Carlsen,M.; Nielsen,J.; Jørgensen,S.B.

    2002-01-01

    Growth and product formation by a selected variant of Aspergillus oryzae showing high alpha-amylase production was studied in continuous cultivations carried out at six different specific growth rates, using glucose as the growth-limiting nutrient. The analysis of the steady-state data revealed that the variant and wild-type strains were similar with respect to glucose uptake system and stoichiometric coefficients. However, the variant was capable of maintaining an enzyme production as high a...

  5. Molecular characterization of Aspergillus fumigatus isolated from raw cow milk in Argentina: Molecular typing of A. fumigatus from raw cow milk.

    Science.gov (United States)

    Pena, Gabriela A; Alonso, Verónica; Manini, Marina Velasco; Pellegrino, M; Cavaglieri, Lilia R

    2018-06-20

    Aspergillus fumigatus, the major etiological agent of human and animal aspergillosis, is a gliotoxinogenic species into section Fumigati commonly found in contaminated animal environments. In dairy herds, exposed areas of lactating cows, as mammalian glandule, can be easily contaminated by them. This study was aimed to identify A. fumigatus sensu lato strains (identified based on morphology) isolated from raw cow milk at species level, by morphological and molecular techniques, and to estimate their genetic variability. Forty-five A. fumigatus strains showed similar RAPD profiles (generated with PELF and URP1F primers) to each other and to A. fumigatus sensu stricto reference strains; also, they were almost identical to clinical human and feed-borne A. fumigatus strains included in the assay, since their similarity coefficient ranged from 0.7 to 1.00. Therefore, all strains were characterized as belonging to A. fumigatus sensu stricto species. This result was supported by sequencing the benA gene of selected strains and by maximum parsimony analysis. In addition, RAPD fingerprinting demonstrated intra-specific genetic variability into the A. fumigatus sensu stricto cluster. The results found in this study strengthen the fact that A. fumigatus sensu stricto is the predominant species in the Aspergillus section Fumigati found in animal environments such as dairy herd environments, while other species such as A. novofumigatus, A. fumigatiaffinis, A. udagawae and A. lentulus may be rarely isolated. Since no differences between animal and human strains were observed they can become pathogenic also for farm handlers'. Moreover, the presence of A. fumigatus sensu stricto in raw cow milk is probably a very important risk factor since milk and its by-products are generally indented for human consumption, then gliotoxin could be transferred to them. Copyright © 2018. Published by Elsevier B.V.

  6. Effect of irradiation on aflatoxin production by Aspergillus flavus

    International Nuclear Information System (INIS)

    Ito, Hitoshi; Jintana Bunnak; Guzman, Z.M. de; Ishigaki, Isao

    1991-01-01

    The effects of repeated exposure to gamma irradiation on Aspergillus flavus var. columnaris S46 was studied in terms of the development of increased radioresistance and mutations. Original D 10 value was obtained as 0.22 kGy and increased a little after 6 times exposure at a dose of 0.8 kGy. Mutation ratios such as morphological changes and aflatoxin production were not remarkably changed even after 6 times exposure. A little stimulation of production of aflatoxin B 1 occurred by irradiation of spores of strains S46, E11 and E14 at 0.4 and 0.6 kGy in Synthetic Low Salts broth after incubation for 10 days at 25degC. The levels of aflatoxin B 1 was also increased 13 to 40% by incubation of irradiated spores of S46 strain at 1 kGy on autoclaved polished rice, black pepper and red pepper. However, these stimulation effects were not Observed after infection of these cultivates of irradiated sores to fresh media. (author)

  7. 21 CFR 866.3040 - Aspergillus spp. serological reagents.

    Science.gov (United States)

    2010-04-01

    ... (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3040 Aspergillus... consist of antigens and antisera used in various serological tests to identify antibodies to Aspergillus...

  8. High sequence variations in the region containing genes encoding a cellular morphogenesis protein and the repressor of sexual development help to reveal origins of Aspergillus oryzae.

    Science.gov (United States)

    Chang, Perng-Kuang; Scharfenstein, Leslie L; Solorzano, Cesar D; Abbas, Hamed K; Hua, Sui-Sheng T; Jones, Walker A; Zablotowicz, Robert M

    2015-05-04

    Aspergillus oryzae and Aspergillus flavus are closely related fungal species. The A. flavus morphotype that produces numerous small sclerotia (S strain) and aflatoxin has a unique 1.5 kb deletion in the norB-cypA region of the aflatoxin gene cluster (i.e. the S genotype). Phylogenetic studies have indicated that an isolate of the nonaflatoxigenic A. flavus with the S genotype is the ancestor of A. oryzae. Genome sequence comparison between A. flavus NRRL3357, which produces large sclerotia (L strain), and S-strain A. flavus 70S identified a region (samA-rosA) that was highly variable in the two morphotypes. A third type of samA-rosA region was found in A. oryzae RIB40. The three samA-rosA types were later revealed to be commonly present in A. flavus L-strain populations. Of the 182 L-strain A. flavus field isolates examined, 46%, 15% and 39% had the samA-rosA type of NRRL3357, 70S and RIB40, respectively. The three types also were found in 18 S-strain A. flavus isolates with different proportions. For A. oryzae, however, the majority (80%) of the 16 strains examined had the RIB40 type and none had the NRRL3357 type. The results suggested that A. oryzae strains in the current culture collections were mostly derived from the samA-rosA/RIB40 lineage of the nonaflatoxigenic A. flavus with the S genotype. Published by Elsevier B.V.

  9. Biomass sorghum as a novel substrate in solid-state fermentation for the production of hemicellulases and cellulases by Aspergillus niger and A. fumigatus.

    Science.gov (United States)

    Dias, L M; Dos Santos, B V; Albuquerque, C J B; Baeta, B E L; Pasquini, D; Baffi, M A

    2018-03-01

    We investigated the role of carbon and nitrogen sources in the production of cellulase and hemicellulase by Aspergillus strains. The strains Aspergillus niger SCBM1 and Aspergillus fumigatus SCBM6 were cultivated under solid-state fermentation (SSF), with biomass sorghum (BS) and wheat bran (WB) as lignocellulosic substrates, in different proportions, along with variable nitrogen sources. The best SSF condition for the induction of such enzymes was observed employing A. niger SCBM1 in BS supplemented with peptone; maximum production levels were achieved as follows: 72 h of fermentation for xylanase and exoglucanase (300·07 and 30·64 U g -1 respectively), 120 h for β-glucosidase and endoglucanase (54·90 and 41·47 U g -1 respectively) and 144 h for β-xylosidase (64·88 U g -1 ). This work demonstrated the viability of the use of BS for the production of hemi- and cellulolytic enzymes; the high concentration of celluloses in BS could be associated with the significant production of cellulases, mainly exoglucanase. This is the first study which presents the promising use of biomass sorghum (genetically modified sorghum to increase its biomass content) as an alternative carbon source for the production of enzymes by SSF. © 2017 The Society for Applied Microbiology.

  10. Aspergillus is monophyletic: Evidence from multiple gene phylogenies and extrolites profiles

    Directory of Open Access Journals (Sweden)

    S. Kocsubé

    2016-09-01

    Full Text Available Aspergillus is one of the economically most important fungal genera. Recently, the ICN adopted the single name nomenclature which has forced mycologists to choose one name for fungi (e.g. Aspergillus, Fusarium, Penicillium, etc.. Previously two proposals for the single name nomenclature in Aspergillus were presented: one attributes the name “Aspergillus” to clades comprising seven different teleomorphic names, by supporting the monophyly of this genus; the other proposes that Aspergillus is a non-monophyletic genus, by preserving the Aspergillus name only to species belonging to subgenus Circumdati and maintaining the sexual names in the other clades. The aim of our study was to test the monophyly of Aspergilli by two independent phylogenetic analyses using a multilocus phylogenetic approach. One test was run on the publicly available coding regions of six genes (RPB1, RPB2, Tsr1, Cct8, BenA, CaM, using 96 species of Penicillium, Aspergillus and related taxa. Bayesian (MrBayes and Ultrafast Maximum Likelihood (IQ-Tree and Rapid Maximum Likelihood (RaxML analyses gave the same conclusion highly supporting the monophyly of Aspergillus. The other analyses were also performed by using publicly available data of the coding sequences of nine loci (18S rRNA, 5,8S rRNA, 28S rRNA (D1-D2, RPB1, RPB2, CaM, BenA, Tsr1, Cct8 of 204 different species. Both Bayesian (MrBayes and Maximum Likelihood (RAxML trees obtained by this second round of independent analyses strongly supported the monophyly of the genus Aspergillus. The stability test also confirmed the robustness of the results obtained. In conclusion, statistical analyses have rejected the hypothesis that the Aspergilli are non-monophyletic, and provided robust arguments that the genus is monophyletic and clearly separated from the monophyletic genus Penicillium. There is no phylogenetic evidence to split Aspergillus into several genera and the name Aspergillus can be used for all the species

  11. Fusarium and Aspergillus mycotoxins contaminating wheat silage for dairy cattle feeding in Uruguay.

    Science.gov (United States)

    Del Palacio, Agustina; Bettucci, Lina; Pan, Dinorah

    Wheat is one of the most important cultivated cereals in Uruguay for human consumption; however, when harvest yields are low, wheat is usually used in ensiling for animal feeding. Ensiling is a forage preservation method that allows for storage during extended periods of time while maintaining nutritional values comparable to fresh pastures. Silage is vulnerable to contamination by spoilage molds and mycotoxins because ensilage materials are excellent substrates for fungal growth. The aim of the study was to identify the mycobiota composition and occurrence of aflatoxins and DON from wheat silage. A total of 220 samples of wheat were collected from four farms in the southwest region of Uruguay were silage practices are developed. The main fungi isolated were Fusarium (43%) and Aspergillus (36%), with Fusarium graminearum sensu lato and Aspergillus section Flavi being the most prevalent species. Aflatoxin concentrations in silo bags ranged from 6.1 to 23.3μg/kg, whereas DON levels ranged between 3000μg/kg and 12,400μg/kg. When evaluating aflatoxigenic capacity, 27.5% of Aspergillus section Flavi strains produced AFB1, 5% AFB2, 10% AFG1 and 17.5% AFG2. All isolates of F. graminearum sensu lato produced DON and 15-AcDON. The results from this study contribute to the knowledge of mycobiota and mycotoxins present in wheat silage. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  12. Genome-scale analysis of the high-efficient protein secretion system of Aspergillus oryzae.

    Science.gov (United States)

    Liu, Lifang; Feizi, Amir; Österlund, Tobias; Hjort, Carsten; Nielsen, Jens

    2014-06-24

    The koji mold, Aspergillus oryzae is widely used for the production of industrial enzymes due to its particularly high protein secretion capacity and ability to perform post-translational modifications. However, systemic analysis of its secretion system is lacking, generally due to the poorly annotated proteome. Here we defined a functional protein secretory component list of A. oryzae using a previously reported secretory model of S. cerevisiae as scaffold. Additional secretory components were obtained by blast search with the functional components reported in other closely related fungal species such as Aspergillus nidulans and Aspergillus niger. To evaluate the defined component list, we performed transcriptome analysis on three α-amylase over-producing strains with varying levels of secretion capacities. Specifically, secretory components involved in the ER-associated processes (including components involved in the regulation of transport between ER and Golgi) were significantly up-regulated, with many of them never been identified for A. oryzae before. Furthermore, we defined a complete list of the putative A. oryzae secretome and monitored how it was affected by overproducing amylase. In combination with the transcriptome data, the most complete secretory component list and the putative secretome, we improved the systemic understanding of the secretory machinery of A. oryzae in response to high levels of protein secretion. The roles of many newly predicted secretory components were experimentally validated and the enriched component list provides a better platform for driving more mechanistic studies of the protein secretory pathway in this industrially important fungus.

  13. Alkaline thermostable pectinase enzyme from Aspergillus niger strain MCAS2 isolated from Manaslu Conservation Area, Gorkha, Nepal.

    Science.gov (United States)

    Khatri, Bhim Prakash; Bhattarai, Tribikram; Shrestha, Sangita; Maharjan, Jyoti

    2015-01-01

    Pectinase enzymes are one of the commercially important enzymes having great potential in various industries especially in food industry. Pectinases accounts for 25 % of global food enzymes produced and their market is increasing day by day. Therefore, the exploration of microorganism with novel characteristics has always been the focus of the research. Microorganism dwelling in unique habitat may possess unique characteristics. As such, a pectinase producing fungus Aspergillus niger strain MCAS2 was isolated from soil of Manaslu Conservation Area (MCA), Gorkha, Nepal. The optimum production of pectinase enzyme was observed at 48 h of fermentation. The pectinase enzyme was partially purified by cold acetone treatment followed by Sephadex G-75 gel filtration chromatography. The partially purified enzyme exhibited maximum activity 60 U/mg which was almost 8.5-fold higher than the crude pectinase. The approximate molecular weight of the enzyme was found to be 66 kDa as observed from SDS-PAGE. The pectinase enzyme was active at broad range of temperature (30-70 °C) and pH (6.2-9.2). Optimum temperature and pH of the pectinase enzyme were 50 °C and 8.2 respectively. The enzyme was stable up to 70 °C and about 82 % of pectinase activity was still observed at 100 °C. The thermostable and alkaline nature of this pectinase can meet the demand of various industrial processes like paper and pulp industry, in textile industry, fruit juice industry, plant tissue maceration and wastewater treatment. In addition, the effect of different metal ions on pectinase activity was also studied.

  14. Ion trap MS(n) for identification of gliotoxin as the cytotoxic factor of a marine strain of Aspergillus fumigatus Fresenius.

    Science.gov (United States)

    Grovel, O; Pouchus, Yves François; Robiou du Pont, Thibaut; Montagu, M; Amzil, Z; Verbist, Jean- François

    2002-02-01

    When cultured in a marine solid medium, a strain of Aspergillus fumigatus (Fresenius) isolated from a shellfish-farming area in the Loire estuary (France) produced a highly cytotoxic exudate. To identify the origin of this activity, a cytotoxicity test on KB cells was used to monitor the purification of the exudate, together with electrospray/ion trap/mass spectrometry (ESI/IT/MS(n)) to detect and identify the toxic compound. After three purification stages, a comparison of fullscan analyses of the last six fractions showed that a monocharged compound at m/z 349 was present only in the active fraction, corresponding to the sodium adduct of gliotoxin [C(13)H(14)N(2)O(4)S(2)+Na](+). Isotopic distribution determination showed that the m/z 349 product possessed two sulphur atoms and multi-stage fragmentation confirmed the hypothesis. MS/MS analysis exhibited the characteristic gliotoxin loss of the disulphide intracyclic bridge. MS(3) analysis revealed four main ions and confirmed the identity of the m/z 349 ion. This study points out that the combined use of a KB cells bioassay and ESI/IT/MS(n) allows a fast and very specific detection and elucidation of unidentified cytotoxic products in natural samples. This method does not require total purification, and it allowed us to report the first detection of gliotoxin production in marine conditions.

  15. STABILITY IN REAL TIME OF SOME CRYOPRESERVED MICROBIAL STRAINS WITH REFERENCE TO GENETICALLY MODIFIED MICROORGANISMS

    Directory of Open Access Journals (Sweden)

    DANIELA VINTILĂ

    2007-05-01

    Full Text Available The aim of this work is to analyze the viability of microorganisms from Collection of Industrial Microorganisms from Faculty of Animal Science and Biotechnology – Timisoara, during freezing and thawing as part of cryopreservation technique. The stability in real time of 19 strains cryopreserved in 16% glycerol was evaluated during a 6-months period. The strains studied were: Escherichia coli, Lactobacillus acidophilus, Rhizobium meliloti, Saccharomyces cerevisiae, Aspergillus oryzae, Aspergillus niger, Trichoderma viride, Bacillus globigii, Bacillus licheniformis, and 9 strains of Bacillus subtilis. The strains cryopreserved at -20oC and -70oC were activated using the fast thawing protocol. A better cell recovery was achieved with the -70oC protocol reaching an average viability for E. coli of 86,3%, comparing with 78,6% in -20oC protocol. The cell recovery percentages for the other strains were: 92,4% for L. acidophilus, 93,9% for A.niger, 89% for A. oryzae, 86,7% for T. viride, 94,2% for R. meliloti, 82,1% for S. cerevisiae, 89,9% for B. licheniformis. Regarding the viability of genetically modified microorganisms, the values shows a good recovering after freezing and thawing, even after 180 days of cryopreservation. With the -20oC protocol lower viability was observed due probably to the formation of eutectic mixtures and recrystalization processes.

  16. Aspergillus contaminans

    Science.gov (United States)

    Aspergillus contaminans is described as a new species from the fingernail of a patient with an infected nail. Phylogenetic analysis of four loci (ITS, calmodulin, beta tubulin and RNA polymerase beta, second largest subunit) showed that this species is most closely related to A. carlsbadensis from A...

  17. Lipid composition of cAMP-dependent protein kinase mutants of Aspergillus niger.

    Science.gov (United States)

    Jernejc, Katarina; Bencina, Mojca

    2003-08-29

    Lipid composition of cAMP-dependent protein kinase (PKA) Aspergillus niger mutants with overexpressed or deleted genes for either regulatory and/or the catalytic subunit of PKA was analyzed. Disruption of the gene encoding the PKA regulatory subunit resulted in 20% less total lipids, 30% less neutral lipids, four times more glycolipids and two-fold higher triacylglycerol lipase activity compared to the control strain. Concomitantly a five-fold decrease in phosphatidylcholine, accompanied with 1.5-, 1.8- and 2.8-fold increases in phosphatidylethanolamine, lysophosphatidylethanolamine and phosphatidylinositol, was determined, respectively. The lack of PKA activity, due to the disruption of a gene encoding the PKA catalytic subunit, resulted in a 1.6-times increase in total lipids with two times more neutral lipids associated with lower triacylglycerol lipase activity and a decrease in phospholipids. The mutants with unrestricted PKA activity synthesized twice as much citric acid as the control strain and three times more than strains lacking PKA activity. The results indicate the involvement of cAMP-mediated PKA activity in regulation of lipid biosynthesis as well as citric acid synthesis.

  18. Radiological abnormalities associated with Aspergillus colonization in a cystic fibrosis population

    International Nuclear Information System (INIS)

    McMahon, Michelle A.; Chotirmall, Sanjay Haresh; McCullagh, Brian; Branagan, Peter; McElvaney, N.G.; Logan, P.M.

    2012-01-01

    Objective: To determine if sputum colonization with Aspergillus species in patients with cystic fibrosis (PWCF) correlates with radiological abnormalities and/or a reduction in pulmonary function (FEV1). Methods: We prospectively evaluated 32 PWCF utilizing high resolution computed tomography (HRCT) of the thorax and pulmonary function testing (PFT). The cohort was assessed as two groups: Aspergillus positive (n = 16) and Aspergillus negative (n = 16) based on sputum culture for Aspergillus species. A modified Bhalla scoring system was applied to each HRCT scan by two blinded radiologists. Results: Aspergillus positive patients had more severe and significant bronchiectasis compared to those Aspergillus negative (p < 0.05). This was most marked in the right upper and lower lobes (RUL, RLL). Total Bhalla score was clinically significant in both groups and approached statistical significance between groups (p = 0.063). No difference in pulmonary function between the groups was detected. Conclusion: PWCF colonized by Aspergillus species have greater radiological abnormalities undetectable by PFTs. Early radiological evaluation of Aspergillus colonized PWCF is therefore warranted.

  19. Biosynthesis of components with antifungal activity against Aspergillus spp. using Streptomyces hygroscopicus

    Directory of Open Access Journals (Sweden)

    Dodić Jelena M.

    2015-01-01

    Full Text Available Losses of apple fruit during storage are mainly caused by fungal phytopathogens. Traditionally, postharvest fungal disease is controlled by the application of synthetic fungicides. However, the harmful impact on environment as well as human health largely limits their application. To reduce these problems in agrochemicals usage, new compounds for plant protection, which are eco-friendly, should be developed. The aim of this study is optimization of medium composition in terms of glucose, soybean meal and phosphates content, by applying response surface methodology, for the production of agents with antifungal activity against Aspergillus spp. For biosynthesis was used strain of Streptomyces hygroscopicus isolated from the environment. Experiments were carried out in accordance with Box-Behnken design with three factors on three levels and three repetitions in the central point. Antifungal activity of the obtained cultivation mediums against Aspergillus oryzae and Aspergillus niger was determined, in vitro, using the diffusion - disc method. For determination optimal medium components desirability function was used. Achieved model predicts that the maximum inhibition zone diameter (40.93 mm against test microorganisms is produced when the initial content of glucose, soybean meal and phosphates are 47.77 g/l, 24.54 g/l and 0.98 g/l, respectively. To minimize the consumption of medium components and costs of effluents processing, additional three sets of optimization were made. The chosen method for optimization of medium components was efficient, relatively simple and time and material saving. Obtained results can be used for the further techno-economic analysis of the process to select optimal medium composition for industrial application.

  20. Aspergillus otitis in small animals--a retrospective study of 17 cases.

    Science.gov (United States)

    Goodale, Elizabeth C; Outerbridge, Catherine A; White, Stephen D

    2016-02-01

    Aspergillus spp. are saprophytic opportunistic fungal organisms and are a common cause of otomycosis in humans. Although there have been case reports of Aspergillus otitis externa in dogs, to the best of the authors' knowledge, this is the first retrospective case series describing Aspergillus otitis in dogs and cats. To characterize signalment, putative risk factors, treatments and outcomes of a case series of dogs and cats with Aspergillus otitis. Eight dogs and nine cats diagnosed with Aspergillus otitis. A retrospective review of medical records from 1989 to 2014 identified animals diagnosed with Aspergillus otitis based on culture. All dogs weighed greater than 23 kg. The most common putative risk factors identified in this study were concurrent diseases, therapy causing immunosuppression or a history of an otic foreign body. Aspergillus otitis was unilateral in all study dogs and most cats. Concurrent otitis media was confirmed in three dogs and one cat, and suspected in two additional cats. Aspergillus fumigatus was the most common isolate overall and was the dominant isolate in cats. Aspergillus niger and A. terreus were more commonly isolated from dogs. Animals received various topical and systemic antifungal medications; however, otic lavage under anaesthesia and/or surgical intervention increased the likelihood of resolution of the fungal infection. Aspergillus otitis is uncommon, typically seen as unilateral otitis externa in cats and larger breed dogs with possible risk factors that include immunosuppression and otic foreign bodies; previous antibiotic usage was common. © 2015 ESVD and ACVD.

  1. Constitutive expression of fluorescent protein by Aspergillus var. niger and Aspergillus carbonarius to monitor fungal colonization in maize plants

    Science.gov (United States)

    Aspergillus niger and A. carbonarius are two species in the Aspergillus section Nigri (black-spored aspergilli) frequently associated with peanut (Arachis hypogea), maize (Zea mays), and other plants as pathogens. These infections are symptomless and as such are major concerns since some black aspe...

  2. Expression of Aspergillus hemoglobin domain activities in Aspergillus oryzae grown on solid substrates improves growth rate and enzyme production

    NARCIS (Netherlands)

    Biesebeke, te R.; Boussier, A.; Biezen van, N.; Braaksma, M.; Hondel, van den C.A.M.J.J.; Vos, de W.M.; Punt, P.J.

    2006-01-01

    DNA fragments coding for hemoglobin domains (HBD) were isolated from Aspergillus oryzae and Aspergillus niger. The HBD activities were expressed in A. oryzae by introduction of HBD gene fragments under the control of the promoter of the constitutively expressed gpdA gene. In the transformants,

  3. [Studies on metabolites from marine microorganism Aspergillus terreus collected from nature reserve region of mangrove].

    Science.gov (United States)

    Shen, Yi; Zou, Jianhua; Dai, Jungui

    2011-09-01

    To search for new antitumor active lead compounds from marine microorganism. A marine strain, Aspergillus terreus, was cultured and up-scaled in artificial seawater media, from which the metabolites were isolated and elucidated by using modern spectroscopy techniques. Twelve compounds were isolated from mycelia and fermentation broth of A. terreus. Compounds 1-4 were steroids, compounds 5-8 were organic acids and esters, compound 9 was an alkaloid, compound 10 was an isocoumarin, compound 11 was ceramide, compound 12 was propenyl cyclic pentanediol.

  4. Occurrence of Aspergillus spp. and aflatoxin B1 in Malaysian foods used for human consumption.

    Science.gov (United States)

    Reddy, Kasa R N; Farhana, Nazira I; Salleh, Baharuddin

    2011-05-01

    Malaysian population widely consumes the cereal-based foods, oilseeds, nuts, and spices in their daily diet. Mycotoxigenic fungi are well known to invade food products under storage conditions and produce mycotoxins that have threat to human and animal health. Therefore, determining toxigenic fungi and aflatoxin B(1) (AFB1) in foods used for human consumption is of prime importance to develop suitable management strategies and to minimize risk. Ninety-five food products marketed in Penang, Malaysia were randomly collected from different supermarkets and were analyzed for presence of Aspergillus spp. by agar plate assay and AFB1 by enzyme-linked immunosorbent assay (ELISA). A. flavus was the dominant fungi in all foods followed by A. niger. Fifty-five A. flavus strains were tested for their ability to produce aflatoxins on rice grain substrate. Thirty-six (65.4%) strains out of 55 produced AFB1 ranging from 1700 to 4400 μg/kg and 17 strains (31%) produced AFB2 ranging from 620 to 1670 μg/kg. Natural occurrence of AFB1 could be detected in 72.6% food products ranging from 0.54 to 15.33 μg/kg with a mean of 1.95 μg/kg. Maximum AFB1 levels were detected in peanut products ranging from 1.47 to 15.33 μg/kg. AFB1 levels detected in all food products were below the Malaysian permissible limits (<35 μg/kg). Aspergillus spp. and AFB1 was not detected in any cookies tested. Although this survey was not comprehensive, it provides valuable information on aflatoxin levels in foods marketed in Malaysia. © 2011 Institute of Food Technologists®

  5. Azole-Resistance in Aspergillus terreus and Related Species: An Emerging Problem or a Rare Phenomenon?

    Directory of Open Access Journals (Sweden)

    Tamara Zoran

    2018-03-01

    Full Text Available Objectives: Invasive mold infections associated with Aspergillus species are a significant cause of mortality in immunocompromised patients. The most frequently occurring aetiological pathogens are members of the Aspergillus section Fumigati followed by members of the section Terrei. The frequency of Aspergillus terreus and related (cryptic species in clinical specimens, as well as the percentage of azole-resistant strains remains to be studied.Methods: A global set (n = 498 of A. terreus and phenotypically related isolates was molecularly identified (beta-tubulin, tested for antifungal susceptibility against posaconazole, voriconazole, and itraconazole, and resistant phenotypes were correlated with point mutations in the cyp51A gene.Results: The majority of isolates was identified as A. terreus (86.8%, followed by A. citrinoterreus (8.4%, A. hortai (2.6%, A. alabamensis (1.6%, A. neoafricanus (0.2%, and A. floccosus (0.2%. One isolate failed to match a known Aspergillus sp., but was found most closely related to A. alabamensis. According to EUCAST clinical breakpoints azole resistance was detected in 5.4% of all tested isolates, 6.2% of A. terreus sensu stricto (s.s. were posaconazole-resistant. Posaconazole resistance differed geographically and ranged from 0% in the Czech Republic, Greece, and Turkey to 13.7% in Germany. In contrast, azole resistance among cryptic species was rare 2 out of 66 isolates and was observed only in one A. citrinoterreus and one A. alabamensis isolate. The most affected amino acid position of the Cyp51A gene correlating with the posaconazole resistant phenotype was M217, which was found in the variation M217T and M217V.Conclusions:Aspergillus terreus was most prevalent, followed by A. citrinoterreus. Posaconazole was the most potent drug against A. terreus, but 5.4% of A. terreus sensu stricto showed resistance against this azole. In Austria, Germany, and the United Kingdom posaconazole-resistance in all A. terreus

  6. Effect of temperature and water activity on the production of fumonisins by Aspergillus niger and different Fusarium species

    DEFF Research Database (Denmark)

    Mogensen, Jesper Mølgaard; Nielsen, Kristian Fog; Samson, Robert A.

    2009-01-01

    Background Fumonisins are economically important mycotoxins which until recently were considered to originate from only a few Fusarium species. However recently a putative fumonisin gene cluster was discovered in two different Aspergillus niger strains followed by detection of an actual fumonisin B......2 (FB2) production in four strains of this biotechnologically important workhorse. Results In the present study, a screening of 5 A. niger strains and 25 assumed fumonisin producing Fusarium strains from 6 species, showed that all 5 A. niger strains produced FB2 and 23 of 25 Fusarium produced...... fumonisin B1 and other isoforms (fumonisin B2 and B3). Five A. niger and five Fusarium spp. were incubated at six different temperatures from 15-42°C on Czapek Yeast Agar +5% salt or Potato Dextrose Agar. A. niger had the highest production of FB2 at 25-30°C whereas Fusarium spp. had the maximal production...

  7. Chronological aging in conidia of pathogenic Aspergillus: Comparison between species.

    Science.gov (United States)

    Oliveira, Manuela; Pereira, Clara; Bessa, Cláudia; Araujo, Ricardo; Saraiva, Lucília

    2015-11-01

    Aspergillus fumigatus, Aspergillus flavus, Aspergillus terreus and Aspergillus niger are common airborne fungi, and the most frequent causative agents of human fungal infections. However, the resistance and lifetime persistence of these fungi in the atmosphere, and the mechanism of aging of Aspergillus conidia are unknown.With this work, we intended to study the processes underlying conidial aging of these four relevant and pathogenic Aspergillus species. Chronological aging was therefore evaluated in A. fumigatus, A. flavus, A. terreus and A. niger conidia exposed to environmental and human body temperatures. The results showed that the aging process in Aspergillus conidia involves apoptosis,with metacaspase activation, DNA fragmentation, and reactive oxygen species production, associated with secondary necrosis. Distinct results were observed for the selected pathogenic species. At environmental conditions, A. niger was the species with the highest resistance to aging, indicating a higher adaption to environmental conditions, whereas A. flavus followed by A. terreus were the most sensitive species. At higher temperatures (37 °C), A. fumigatus presented the longest lifespan, in accordance with its good adaptation to the human body temperature. Altogether,with this work new insights regarding conidia aging are provided, which may be useful when designing treatments for aspergillosis.

  8. АЛЛЕРГЕНЫ ASPERGILLUS NIGER И ASPERGILLUS FUMIGATUS

    OpenAIRE

    БАЯЗИТОВА А.А.; ГЛУШКО Н.И.; ЛИСОВСКАЯ С.А.; ХАЛДЕЕВА Е.В.; ПАРШАКОВ В.Р.; ИЛЬИНСКАЯ О.И.

    2016-01-01

    Риск развития микогенной аллергии, наряду со способностью вызывать микозы и оказывать токсическое действие, является одним из медицински значимых свойств грибов. В обзоре рассмотрены грибы рода Aspergillus, в частности, Aspergillus niger и Aspergillus fumigatus, как одни из важных источников ингаляционных аллергенов. Предоставлена оценка аллергенности Aspergillus niger и Aspergillus fumigatus, также приведена более подробная характеристика наиболее значимых аллергенов....

  9. Assessment of Aspergillus niger biofilm growth kinetics in ...

    African Journals Online (AJOL)

    Jane

    2011-10-12

    Oct 12, 2011 ... other hand, A. niger biofilm growth followed a logistic model having higher maximal specific growth rate than ...... Growth estimation of Aspergillus oryzae cultured on ... Initial intracellular proteome profile of Aspergillus niger.

  10. Production and characterization of two major Aspergillus oryzae secreted prolyl endopeptidases able to efficiently digest proline-rich peptides of gliadin.

    Science.gov (United States)

    Eugster, Philippe J; Salamin, Karine; Grouzmann, Eric; Monod, Michel

    2015-12-01

    Prolyl endopeptidases are key enzymes in the digestion of proline-rich proteins. Fungal extracts rich in prolyl endopeptidases produced by a species such as Aspergillus oryzae used in food fermentation would be of particular interest for the development of an oral enzyme therapy product in patients affected by intolerance to gluten. Two major A. oryzae secreted prolyl endopeptidases of the MEROPS S28 peptidase family, AoS28A and AoS28B, were identified when this fungus was grown at acidic pH in a medium containing soy meal protein or wheat gliadin as the sole source of nitrogen. AoS28B was produced by 12 reference A. oryzae strains used in food fermentation. AoS28A was secreted by six of these 12 strains. This protease is the orthologue of the previously characterized Aspergillus fumigatus (AfuS28) and Aspergillus niger (AN-PEP) prolyl endopeptidases which are encoded by genes with a similar intron-exon structure. Large amounts of secreted AoS28A and AoS28B were obtained by gene overexpression in A. oryzae. AoS28A and AoS28B are endoproteases able to cleave N-terminally blocked proline substrates. Both enzymes very efficiently digested the proline-rich 33-mer of gliadin, the most representative immunotoxic peptide deriving from gliadin, with some differences in terms of specificity and optimal pH. Digestion of the gliadin peptide in short peptides with both enzymes was found to occur from its N terminus.

  11. Mutagenesis of Aspergillus oryzae IPT-301 to improve the production of β-fructofuranosidase

    Directory of Open Access Journals (Sweden)

    Beatriz Guilarte Maresma

    2010-03-01

    Full Text Available Aspergillus oryzae IPT-301, previously reported as a β-fructofuranosidase producing microorganism, was successfully mutated using UV irradiation at 253.7 nm followed by the screening of survivors resistant to certain stress conditions. Strains were first subjected to the β-fructofuranosidase activity assay using a portion from the colony grown in Petri dish as the enzyme source. Seven mutants with fructofuranosidase activity values relative to the parent culture between 140 -190% were selected from survivors grown at temperature of 40ºC or 0.018% (w/v sodium dodecyl sulfate concentration. They were cultivated on a rotary shaker to characterize mycelium and extracellular fructosyltransferase activities. Three mutants named IPT-745, IPT-746 and IPT-748 showed the highest amount of mycelium activity whose values increased 1.5 -1.8 fold, compared with the parent strain. It was found that more than 55% of total enzyme activity (mycelium- plus extracellular- activity from these strains was detected in the mycelium fraction. Only one mutant, IPT-747, exceeded the amount of extracellular enzyme exhibited by the parent strain (1.5 times. This mutant also showed the highest value of total fructosyltransferase activity.

  12. Mutants of Aspergillus nidulans with increased resistance to the alkylating agent, N-methyl-N'-nitro-N-nitrosoguanidine.

    Science.gov (United States)

    Hooley, P; Shawcross, S G; Strike, P

    1988-05-01

    The isolation and characterisation of mutants of Aspergillus nidulans showing resistance to MNNG is described. Such isolates were stable through prolonged subculture in the absence of the selective agent, and resistance segregated as an allele of a single gene in meiotic and mitotic analysis. MNNG-resistant strains showed an increase in resistance to EMS and UV irradiation but no cross-resistance to MMS was detected. Possible mechanisms of resistance to alkylating agents are discussed.

  13. Isolation and genetic analysis of Aspergillus niger mutants with reduced extracellular glucoamylase

    International Nuclear Information System (INIS)

    Valent, G.U.; Calil, M.R.; Bonatelli Junior, R.

    1992-01-01

    Mutants with impaired production of extracellular glucoamylase were isolated at a high frequency (2% of survivors) from an Aspergillus niger strain treated with UV light. These were designated as low glucoamylase producers (lgp, up to 30% of the parental yield) and medium producers (mgp, a 35 to 50% decrease in enzyme level). All the mutants were shown to be recessive; one strain segregated two unlinked genes. Complementation tests, and segregation from heterozygous diploid, suggested at least three to four unlinked genes, each able to impair glucoamylase production. There is evidence of a single structural gene for glucoamylase in A. niger. Therefore, as production of extracellular enzymes is normally the final result of several steps at intracellular and membrane levels, including regulation of enzyme synthesis, we suggest intergenic interaction that controls extracellular enzyme accumulation and that mutation in any of these genes would result in impaired production. (author)

  14. Extrolites of Aspergillus fumigatus and Other Pathogenic Species in Aspergillus Section Fumigati

    Science.gov (United States)

    Frisvad, Jens C.; Larsen, Thomas O.

    2016-01-01

    Aspergillus fumigatus is an important opportunistic human pathogen known for its production of a large array of extrolites. Up to 63 species have been described in Aspergillus section Fumigati, some of which have also been reliably reported to be pathogenic, including A. felis, A. fischeri, A. fumigatiaffinis, A. fumisynnematus, A. hiratsukae, A. laciniosus, A. lentulus, A. novofumigatus, A. parafelis, A. pseudofelis, A. pseudoviridinutans, A. spinosus, A. thermomutatus, and A. udagawae. These species share the production of hydrophobins, melanins, and siderophores and ability to grow well at 37°C, but they only share some small molecule extrolites, that could be important factors in pathogenicity. According to the literature gliotoxin and other exometabolites can be contributing factors to pathogenicity, but these exometabolites are apparently not produced by all pathogenic species. It is our hypothesis that species unable to produce some of these metabolites can produce proxy-exometabolites that may serve the same function. We tabulate all exometabolites reported from species in Aspergillus section Fumigati and by comparing the profile of those extrolites, suggest that those producing many different kinds of exometabolites are potential opportunistic pathogens. The exometabolite data also suggest that the profile of exometabolites are highly specific and can be used for identification of these closely related species. PMID:26779142

  15. Upgrading of citric acid production from cheap carbohydrate sources as affected by aspergillus

    International Nuclear Information System (INIS)

    Elbatal, A.I.; Khalaf, S.A.; Khalil, A.H.

    1995-01-01

    Five strains of aspergillus niger (EMCC 102, EMCC 104, EMCC 111, EMCC 132 and EMCC 147) were for citric acid production at different incubation period using different cheap carbohydrate substrates, such as beet, cane and citrus molasses and milk whey. A. niger EMCC 111 was found to be the most potent strain for citric acid production from beet molasses after 11 days of incubation at 30 degree. The studies concerning molasses concentration and nitrogen sources (inorganic and organic sources with different concentration, revealed that 30 g% beet molasses and ammonium sulfate with 0.05 g% as N 2 content, gave the highest production of citric acid. Gamma irradiated inocula of A. niger EMCC 111 at doses (0.05-0.8 KGy), showed that the dose 0.4 KGy was the optimum for maximum citric acid production. 8 tabs

  16. [Aspergillus fumigatus endocarditis in a patient with a biventricular pacemaker].

    Science.gov (United States)

    Cuesta, José M; Fariñas, María C; Rodilla, Irene G; Salesa, Ricardo; de Berrazueta, José R

    2005-05-01

    Aspergillus fumigatus endocarditis is one of the rarest and severest complications in cardiological patients. We describe a patient with an intracardial pacemaker who was diagnosed as having Aspergillus fumigatus endocarditis. Postmortem examination showed a large, Aspergillus-infected thrombus encased in the right ventricle, pulmonary trunk and main pulmonary branches.

  17. A Novel Zn2-Cys6 Transcription Factor AtrR Plays a Key Role in an Azole Resistance Mechanism of Aspergillus fumigatus by Co-regulating cyp51A and cdr1B Expressions

    Science.gov (United States)

    Shimizu, Kiminori; Paul, Sanjoy; Ohba, Ayumi; Gonoi, Tohru; Watanabe, Akira; Gomi, Katsuya

    2017-01-01

    Successful treatment of aspergillosis caused by Aspergillus fumigatus is threatened by an increasing incidence of drug resistance. This situation is further complicated by the finding that strains resistant to azoles, the major antifungal drugs for aspergillosis, have been widely disseminated across the globe. To elucidate mechanisms underlying azole resistance, we identified a novel transcription factor that is required for normal azole resistance in Aspergillus fungi including A. fumigatus, Aspergillus oryzae, and Aspergillus nidulans. This fungal-specific Zn2-Cys6 type transcription factor AtrR was found to regulate expression of the genes related to ergosterol biosynthesis, including cyp51A that encodes a target protein of azoles. The atrR deletion mutant showed impaired growth under hypoxic conditions and attenuation of virulence in murine infection model for aspergillosis. These results were similar to the phenotypes for a mutant strain lacking SrbA that is also a direct regulator for the cyp51A gene. Notably, AtrR was responsible for the expression of cdr1B that encodes an ABC transporter related to azole resistance, whereas SrbA was not involved in the regulation. Chromatin immunoprecipitation assays indicated that AtrR directly bound both the cyp51A and cdr1B promoters. In the clinically isolated itraconazole resistant strain that harbors a mutant Cyp51A (G54E), deletion of the atrR gene resulted in a hypersensitivity to the azole drugs. Together, our results revealed that AtrR plays a pivotal role in a novel azole resistance mechanism by co-regulating the drug target (Cyp51A) and putative drug efflux pump (Cdr1B). PMID:28052140

  18. Aspergillus Osteomyelitis: Epidemiology, Clinical Manifestations, Management, and Outcome

    Science.gov (United States)

    Gamaletsou, Maria N.; Rammaert, Blandine; Bueno, Marimelle A.; Moriyama, Brad; Sipsas, Nikolaos V.; Kontoyiannis, Dimitrios P.; Roilides, Emmanuel; Zeller, Valerie; Prinapori, Roberta; Tajaldeen, Saad Jaber; Brause, Barry; Lortholary, Olivier; Walsh, Thomas J.

    2014-01-01

    Background The epidemiology, pathogenesis, diagnosis, and management of Aspergillus osteomyelitis are not well understood. Methods Protocol-defined cases of Aspergillus osteomyelitis published in the English literature were reviewed for comorbidities, microbiology, mechanisms of infection, clinical manifestations, radiological findings, inflammatory biomarkers, antifungal therapy, and outcome. Results Among 180 evaluable patients, 127 (71%) were males. Possible predisposing medical conditions in 103 (57%) included pharmacological immunosuppression, primary immunodeficiency, and neutropenia. Seventy-three others (41%) had prior open fracture, trauma or surgery. Eighty (44%) followed a hematogenous mechanism, 58 (32%) contiguous infections, and 42 (23%) direct inoculation. Aspergillus osteomyelitis was the first manifestation of aspergillosis in 77%. Pain and tenderness were present in 80%. The most frequently infected sites were vertebrae (46%), cranium (23%), ribs (16%), and long bones (13%). Patients with vertebral Aspergillus osteomyelitis had more previous orthopedic surgery (19% vs 0%; P=0.02), while those with cranial osteomyelitis had more diabetes mellitus (32% vs 8%; P=0.002) and prior head/neck surgery (12% vs 0%; P=0.02). Radiologic findings included osteolysis, soft-tissue extension, and uptake on T2-weighted images. Vertebral body Aspergillus osteomyelitis was complicated by spinal-cord compression in 47% and neurological deficits in 41%. Forty-four patients (24%) received only antifungal therapy, while 121(67%) were managed with surgery and antifungal therapy. Overall mortality was 25%. Median duration of therapy was 90 days (range, 10–772 days). There were fewer relapses in patients managed with surgery plus antifungal therapy in comparison to those managed with antifungal therapy alone (8% vs 30%; P=0.006). Conclusions Aspergillus osteomyelitis is a debilitating infection affecting both immunocompromised and immunocompetent patients. The most

  19. Modifying action of DNA synthesis precursors on Aspergillus nidulans conidium irradiated by ultraviolet and X-rays

    International Nuclear Information System (INIS)

    Muronets, E.M.; Kameneva, S.V.

    1975-01-01

    Modification of inactivation action of radiation on conidia Aspergillus nidulans, UVS + and UVS strains, by desoxynucleosides, purine and pyrimidine bases is shown. The modification manifested in increased conidia survival is revealed when the precursor of DNA synthesis is added to the suspension before exposure to ultraviolet or X-rays. In the case of postradiation application of the substance no modification is observed. The modifying effect of different precursors becomes equally apparent with equimolar solutions and increases at higher concentration of the latter. An increase in thymidine endogenic pool in the exposed conidia does not affect their survival. When conidia are exposed to ultraviolet rays through a thymidine filter the survival rate increases to the same extent as in the case when they are exposed to irradiation in thymidine solution. The authors suggest that modification of the inactivating radiation action by DNA precursors at exposure of conidia Aspergillus nidulans is caused by the radioprotective effect of precursors not related to reparation [ru

  20. Septic arthritis due to tubercular and Aspergillus co-infection

    Directory of Open Access Journals (Sweden)

    Mukesh Kumar

    2016-01-01

    Full Text Available Aspergillus septic arthritis is a rare and serious medical and surgical problem. It occurs mainly in immunocompromised patients. Aspergillus fumigatus is the most common causative organism followed by Aspergillus flavus. The most common site affected is knee followed by shoulder, ankle, wrist, hip and sacroiliac joint. Debridement and voriconazole are primary treatment of articular aspergilosis. To the best of our knowledge, there are no reported cases of co-infection of tuberculosis (TB and Aspergillus infecting joints. We report a case of co-infection of TB and A. flavus of hip and knee of a 60-year-old male, with type 2 diabetes mellitus. He was treated with debridement, intravenous voriconazole, and antitubercular drugs.

  1. Septic arthritis due to tubercular and Aspergillus co-infection.

    Science.gov (United States)

    Kumar, Mukesh; Thilak, Jai; Zahoor, Adnan; Jyothi, Arun

    2016-01-01

    Aspergillus septic arthritis is a rare and serious medical and surgical problem. It occurs mainly in immunocompromised patients. Aspergillus fumigatus is the most common causative organism followed by Aspergillus flavus. The most common site affected is knee followed by shoulder, ankle, wrist, hip and sacroiliac joint. Debridement and voriconazole are primary treatment of articular aspergilosis. To the best of our knowledge, there are no reported cases of co-infection of tuberculosis (TB) and Aspergillus infecting joints. We report a case of co-infection of TB and A. flavus of hip and knee of a 60-year-old male, with type 2 diabetes mellitus. He was treated with debridement, intravenous voriconazole, and antitubercular drugs.

  2. Citric acid fermentation by gamma ray induced mutants of Aspergillus niger in different carbohydrate media

    Energy Technology Data Exchange (ETDEWEB)

    Anjuman Ara Begum; Naiyyum Choudhury; Mohammad Serajul Islam (Institute of Food and Radiation Biology, Dacca (Bangladesh))

    1990-01-01

    A natural isolate of Aspergillus niger, CA16, and two of its second step mutants, 136/40 and 277/30, grown on different sugar substrates gave maximum citric acid yields of 34, 70, and 126 mg/ml respectively in sucrose medium. Combination of two sugars in the medium at 50% of each improved the yields of citric acid for the sucrose: glucose, glucose: sorbitol, glucose: xylose, and xylose: sorbitol combinations with the mutant strains. Inclusion of galactose in combinations decreased the citric acid yield. (author).

  3. Citric acid fermentation by gamma ray induced mutants of Aspergillus niger in different carbohydrate media

    International Nuclear Information System (INIS)

    Anjuman Ara Begum; Naiyyum Choudhury; Mohammad Serajul Islam

    1990-01-01

    A natural isolate of Aspergillus niger, CA16, and two of its second step mutants, 136/40 and 277/30, grown on different sugar substrates gave maximum citric acid yields of 34, 70, and 126 mg/ml respectively in sucrose medium. Combination of two sugars in the medium at 50% of each improved the yields of citric acid for the sucrose: glucose, glucose: sorbitol, glucose: xylose, and xylose: sorbitol combinations with the mutant strains. Inclusion of galactose in combinations decreased the citric acid yield. (author)

  4. Genetic diversity of Aspergillus fumigatus in indoor hospital environments.

    Science.gov (United States)

    Araujo, Ricardo; Amorim, António; Gusmão, Leonor

    2010-09-01

    Environmental isolates of Aspergillus fumigatus are less studied than those recovered from clinical sources. In the present study, the genetic diversity among such environmental isolates was assessed, as well as their dispersion ability and the acquisition of new strains in 19 medical units of the same hospital. A. fumigatus isolates were genotyped using a single multiplex PCR-based reaction with eight microsatellite markers and an insertion/deletion polymorphism. A total of 130 unique genotypes were found among a total of 250 A. fumigatus isolates. Genotypic diversity ranged from 0.86 to 1 in samples from hospital rooms, and there was no correlation between these samples and the presence of high-efficiency particulate air filters or any other air filtration system. Four of the six most prevalent A. fumigatus strains were recovered from water samples. The occurrence of microvariation was common among environmental isolates, which affected each of the microsatellite markers. The assessment of the genetic diversity of A. fumigatus is a useful tool for illustrating the presence or absence of specific clonal populations in a clinical setting. A. fumigatus populations were highly dynamic indoors, and new populations were found in just a few months. Due to the high indoor dispersion capability of A. fumigatus, more attention should be given to strains with increased pathogenic potential or reduced susceptibility to anti-fungal drugs.

  5. Aspergillus waksmanii sp. nov. and Aspergillus marvanovae sp. nov., two closely related species in section Fumigati

    DEFF Research Database (Denmark)

    Hubka, Vit; Peterson, Stephen W.; Frisvad, Jens Christian

    2013-01-01

    Two new and phylogenetically closely related species in Aspergillus section Fumigati are described and illustrated. Homothallic Aspergillus waksmanii sp. nov. was isolated from New Jersey soil (USA) and is represented by the ex-type isolate NRRL 179T (=CCF 4266T=Thom 4138.HS2T=IBT 31900T......). Aspergillus marvanovae sp. nov. was isolated from water with high boracic acid anions content in Dukovany nuclear power station (Czech Republic). The sexual stage of this species is unknown, but the MAT1-1 locus was successfully amplified suggesting that the species is probably heterothallic and teleomorphic...... but is represented by only the ex-type isolate CCM 8003T (=CCF 4037T=NRRL 62486T=IBT 31279T=IFM 60873T). Both species can be distinguished from all previously described species in section Fumigati based on morphology, maximum growth temperature, sequence data from five unlinked loci and unique secondary metabolites...

  6. A rare case of bilateral aspergillus endophthalmitis

    Directory of Open Access Journals (Sweden)

    Saurabh Gupta

    2015-12-01

    Full Text Available Aspergillus endophthalmitis is a devastating inflammatory condition of the intraocular cavities that may result in irreparable loss of vision and rapid destruction of the eye. Almost all cases in the literature have shown an identified source causing aspergillus endophthalmitis as a result of direct extension of disease. We present a rare case of bilateral aspergillus endophthalmitis. A 72-year-old woman with a history of diabetes mellitus, congenital Hirschsprung disease, and recent culture-positive candida pyelonephritis with hydronephrosis status post-surgical stent placement presented with difficulty opening her eyes. She complained of decreased vision (20/200 with pain and redness in both eyes – right worse then left. Examination demonstrated multiple white fungal balls in both retinas consistent with bilateral fungal endophthalmitis. Bilateral vitreous taps for cultures and staining were performed. Patient was given intravitreal injections of amphotericin B, vancomycin, ceftazidime, and started on oral fluconazole. Patient was scheduled for vitrectomy to decrease organism burden and to remove loculated areas of infection that would not respond to systemic antifungal agents. Four weeks after initial presentation, the fungal cultures revealed mold growth consistent with aspergillus. Patient was subsequently started on voriconazole and fluconazole was discontinued due to poor efficacy against aspergillus. Further workup was conducted to evaluate for the source of infection and seeding. Transthoracic cardiogram was unremarkable for any vegetation or valvular abnormalities. MRI of the orbits and sinuses did not reveal any mass lesions or bony destruction. CT of the chest was unremarkable for infection. Aspergillus endophthalmitis may occur because of one of these several mechanisms: hematogenous dissemination, direct inoculation by trauma, and contamination during surgery. Our patient's cause of bilateral endophthalmitis was through an

  7. Aspergillus fumigatus conidial melanin modulates host cytokine response

    NARCIS (Netherlands)

    L.Y.A. Chai (Louis); M.G. Netea (Mihai); J. Sugui (Janyce); A.G. Vonk (Alieke); W.W.J. van de Sande (Wendy); A. Warris (Adilia); K.J. Kwon-Chung (Kyung); B. Jan Kullberg (Bart)

    2010-01-01

    textabstractMelanin biopigments have been linked to fungal virulence. Aspergillus fumigatus conidia are melanised and are weakly immunogenic. We show that melanin pigments on the surface of resting Aspergillus fumigatus conidia may serve to mask pathogen-associated molecular patterns (PAMPs)-induced

  8. Aspergillus fumigatus conidial melanin modulates host cytokine response.

    NARCIS (Netherlands)

    Chai, L.; Netea, M.G.; Sugui, J.; Vonk, A.G.; Sande, W.W. van de; Warris, A.; Kwon-Chung, K.J.; Kullberg, B.J.

    2010-01-01

    Melanin biopigments have been linked to fungal virulence. Aspergillus fumigatus conidia are melanised and are weakly immunogenic. We show that melanin pigments on the surface of resting Aspergillus fumigatus conidia may serve to mask pathogen-associated molecular patterns (PAMPs)-induced cytokine

  9. Two novel species of Aspergillus section Nigri from Thai coffee beans

    DEFF Research Database (Denmark)

    Noonim, Paramee; Mahakarnchanakul, Warapa; Varga, Janos

    2008-01-01

    Two novel species of Aspergillus section Nigri from Thai coffee beans are described as Aspergillus aculeatinus sp. nov. and Aspergillus sclerotiicarbonarius sp. nov. Their taxonomic status was determined using a polyphasic taxonomic approach with phenotypic (morphology and extrolite profiles...

  10. Gamma-irradiation induced mutagenesis on some microbial strains of interest in food biotechnologies

    International Nuclear Information System (INIS)

    Ferdes, O.S.; Ferdes, M.; Dumitru, E.; Mencinicopschi, G.

    1993-01-01

    In this paper there were presented the results concerning gamma-ray effects on some microbial strains which are of interest in food biotechnologies. The irradiations are performed to a Co-60 source, under several condition, at dose rates between 0.1-2.0 kGy/h and in a dose range between 0.1-20.0 kGy. The microbial strains are of Bacillus subtilis, Aspergillus niger, Mucor pusillus and Monascus rubens from IFC collection. There were established the survival curves and the optimum irradiation doses for mutagenic effects. There were isolated, analysed and characterised some mutant strains, with better properties in obtaining food enzymes and pigments. (orig.)

  11. 21 CFR 173.120 - Carbohydrase and cellulase derived from Aspergillus niger.

    Science.gov (United States)

    2010-04-01

    ... cellulase derived from Aspergillus niger. Carbohydrase and cellulase enzyme preparation derived from Aspergillus niger may be safely used in food in accordance with the following prescribed conditions: (a) Aspergillus niger is classified as follows: Class, Deuteromycetes; order, Moniliales; family, Moniliaceae...

  12. Two novel species of Aspergillus section Nigri from Thai coffee beans.

    NARCIS (Netherlands)

    Noonim, P.; Mahakarnchanakul, W.; Varga, J.; Frisvad, J.C.; Samson, R.A.

    2008-01-01

    Two novel species of Aspergillus section Nigri from Thai coffee beans are described as Aspergillus aculeatinus sp. nov. and Aspergillus sclerotiicarbonarius sp. nov. Their taxonomic status was determined using a polyphasic taxonomic approach with phenotypic (morphology and extrolite profiles) and

  13. Liver injury in invasive aspergillus. Echographic findings

    International Nuclear Information System (INIS)

    Otero Fernandez, R.; Garcia Revillo, J.; Paez Moreno, J.; Zurera Tendero, L.J.

    1994-01-01

    Aspergillus is the second most common mycoses in immuno compromised patients. The invasive form is associated with a mortality of approximately 100%. We present a case of invasive aspergillus in a heart transplant recipient in whom ultrasound disclosed the presence of liver injury which was later confirmed by necropsy. We review the available literature. (Author) 15 refs

  14. New and revisited species in Aspergillus section Nigri

    DEFF Research Database (Denmark)

    Varga, J.; Frisvad, Jens Christian; Kocsube, S.

    2011-01-01

    based on either beta-tubulin or calmodulin sequence data. Aspergillus eucalypticola produced pyranonigrin A, funalenone, aurasperone B and other naphtho-gamma-pyrones. Aspergillus neoniger is also a biseriate species isolated from desert sand in Namibia, and mangrove water in Venezuela, which produces...

  15. Characteristic clinical features of Aspergillus appendicitis: Case report and literature review.

    Science.gov (United States)

    Gjeorgjievski, Mihajlo; Amin, Mitual B; Cappell, Mitchell S

    2015-11-28

    This work aims to facilitate diagnosing Aspergillus appendicitis, which can be missed clinically due to its rarity, by proposing a clinical pentad for Aspergillus appendicitis based on literature review and one new case. The currently reported case of pathologically-proven Aspergillus appendicitis was identified by computerized search of pathology database at William Beaumont Hospital, 1999-2014. Prior cases were identified by computerized literature search. Among 10980 pathology reports of pathologically-proven appendicitis, one case of Aspergillus appendicitis was identified (rate = 0.01%). A young boy with profound neutropenia, recent chemotherapy, and acute myelogenous leukemia presented with right lower quadrant pain, pyrexia, and generalized malaise. Abdominal computed tomography scan showed a thickened appendiceal wall and periappendiceal inflammation, suggesting appendicitis. Emergent laparotomy showed an inflamed, thickened appendix, which was resected. The patient did poorly postoperatively with low-grade-fevers while receiving antibacterial therapy, but rapidly improved after initiating amphotericin therapy. Microscopic examination of a silver stain of the appendectomy specimen revealed fungi with characteristic Aspergillus morphology, findings confirmed by immunohistochemistry. Primary Aspergillus appendicitis is exceptionally rare, with only 3 previously reported cases. All three cases presented with (1)-neutropenia, (2)-recent chemotherapy, (3)-acute leukemia, and (4)-suspected appendicitis; (5)-the two prior cases initially treated with antibacterial therapy, fared poorly before instituting anti-Aspergillus therapy. The current patient satisfied all these five criteria. Based on these four cases, a clinical pentad is proposed for Aspergillus appendicitis: clinically-suspected appendicitis, neutropenia, recent chemotherapy, acute leukemia, and poor clinical response if treated solely by antibacterial/anti-candidial therapy. Patients presenting with

  16. Characterization of Aspergillus species based on fatty acid profiles.

    Science.gov (United States)

    Fraga, Marcelo E; Santana, Djalva Maria N; Gatti, Mario Jorge; Direito, Gloria Maria; Cavaglieri, Lilia R; Rosa, Carlos Alberto R

    2008-09-01

    Cellular fatty acid (FA) composition was utilized as a taxonomic tool to discriminate between different Aspergillus species. Several of the tested species had the same FA composition and different relative FA concentrations. The most important FAs were palmitic acid (C16:0), estearic acid (C18:0), oleic acid (C18:1) and linoleic acid (C18:2), which represented 95% of Aspergillus FAs. Multivariate data analysis demonstrated that FA analysis is a useful tool for differentiating species belonging to genus Aspergillus. All the species analyzed showed significantly FA acid profiles (p < 0.001). Furthermore, it will be possible to distinguish among Aspergillus spp. in the Flavi Section. FA composition can serve as a useful tool for the identification of filamentous fungi.

  17. New cytotoxic furan from the marine sediment-derived fungi Aspergillus niger.

    Science.gov (United States)

    Uchoa, Paula Karina S; Pimenta, Antonia T A; Braz-Filho, Raimundo; de Oliveira, Maria da Conceição F; Saraiva, Natália N; Rodrigues, Barbara S F; Pfenning, Ludwig H; Abreu, Lucas M; Wilke, Diego V; Florêncio, Katharine G D; Lima, Mary Anne S

    2017-11-01

    A fungal strain of Aspergillus niger was recovered from sediments collected in the Northeast coast of Brazil (Pecém's offshore port terminal). Cultivation in different growth media yielded a new ester furan derivative, 1, along with malformin A1, malformin C, cyclo (trans-4-hydroxy-L-Pro-L-Leu), cyclo (trans-4-hydroxy-L-Pro-L-Phe), cyclo (L-Pro-L-Leu), cyclo (L-Pro-L-Phe), pseurotin D, pseurotin A, chlovalicin, cyclo (L-Pro-L-Tyr) and cyclo (L-Pro-L-Val). Compound 1 was cytotoxic against HCT-116 cell line, showing IC 50  = 2.9 μg/mL (CI 95% from 1.8 to 4.7 μg/mL).

  18. FluG affects secretion in colonies of Aspergillus niger.

    Science.gov (United States)

    Wang, Fengfeng; Krijgsheld, Pauline; Hulsman, Marc; de Bekker, Charissa; Müller, Wally H; Reinders, Marcel; de Vries, Ronald P; Wösten, Han A B

    2015-01-01

    Colonies of Aspergillus niger are characterized by zonal heterogeneity in growth, sporulation, gene expression and secretion. For instance, the glucoamylase gene glaA is more highly expressed at the periphery of colonies when compared to the center. As a consequence, its encoded protein GlaA is mainly secreted at the outer part of the colony. Here, multiple copies of amyR were introduced in A. niger. Most transformants over-expressing this regulatory gene of amylolytic genes still displayed heterogeneous glaA expression and GlaA secretion. However, heterogeneity was abolished in transformant UU-A001.13 by expressing glaA and secreting GlaA throughout the mycelium. Sequencing the genome of UU-A001.13 revealed that transformation had been accompanied by deletion of part of the fluG gene and disrupting its 3' end by integration of a transformation vector. Inactivation of fluG in the wild-type background of A. niger also resulted in breakdown of starch under the whole colony. Asexual development of the ∆fluG strain was not affected, unlike what was previously shown in Aspergillus nidulans. Genes encoding proteins with a signal sequence for secretion, including part of the amylolytic genes, were more often downregulated in the central zone of maltose-grown ∆fluG colonies and upregulated in the intermediate part and periphery when compared to the wild-type. Together, these data indicate that FluG of A. niger is a repressor of secretion.

  19. Morphological changes of Aspergillus ochraceus irradiated on peanut grains

    International Nuclear Information System (INIS)

    Borges, Valeria B.; Maia, Maria C.A.; Couto, Maria A.P.G.; Vital, Helio C.; Souza, Mauro C.L.

    2011-01-01

    This study investigated the morphological changes of Aspergillus ochraceus inoculated on peanuts and irradiated. The effects of radiation on the morphology of the fungus were evaluated macroscopically and microscopically. The experiments were performed with samples of peanuts in natura (raw and peeled) purchased in supermarkets in the city of Rio de Janeiro. The samples were inoculated with the fungal strain Aspergillus ochraceus (CMT 00145) in petri plates that were kept incubated in a BOD germination chamber at 25 degree C for 5 days. They were then exposed to gamma radiation from a cesium-137 source to doses of 0, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, and 5.5 kGy at an average dose rate of approximately 1.6 kGy/h. Radiosensitivity as well as morphological and microscopic changes induced by irradiation were investigated for colonies kept for 7 days in MEA medium at 25 degree C. Inactivation was found to occur for all colonies irradiated with 5 kGy and for none irradiated with 2.0 kGy or less. Also investigated was the time needed for irradiated colonies to resume growth. The impact of irradiation on the morphological and microscopic characteristics of the fungus were found to become significant at doses above 1 kGy, causing some structures to gradually shrink or even vanish with increasing dose. (author)

  20. Morphological changes of Aspergillus ochraceus irradiated on peanut grains

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Valeria B.; Maia, Maria C.A.; Couto, Maria A.P.G., E-mail: antun@eq.ufrj.br, E-mail: gimenes@eq.ufrj.br [Coordenaao s Programas de Pos-graduacaoem Processos Quimicos e Bioquimicos. Escola de Quimica. Universidade Federal do Rio de Janeiro (EQ/ UFRJ), Rio de Janeiro, RJ (Brazil); Vital, Helio C., E-mail: vital@ctex.eb.br [Secao de Defesa Nuclear do Centro Tecnologico do Exercito (CTEx), Guaratiba, Rio de Janeiro, RJ (Brazil); Souza, Mauro C.L. [Laboratorio de Instrumentacao Nuclear (LIN/COPPE/UFRJ). Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil)

    2011-07-01

    This study investigated the morphological changes of Aspergillus ochraceus inoculated on peanuts and irradiated. The effects of radiation on the morphology of the fungus were evaluated macroscopically and microscopically. The experiments were performed with samples of peanuts in natura (raw and peeled) purchased in supermarkets in the city of Rio de Janeiro. The samples were inoculated with the fungal strain Aspergillus ochraceus (CMT 00145) in petri plates that were kept incubated in a BOD germination chamber at 25 degree C for 5 days. They were then exposed to gamma radiation from a cesium-137 source to doses of 0, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, and 5.5 kGy at an average dose rate of approximately 1.6 kGy/h. Radiosensitivity as well as morphological and microscopic changes induced by irradiation were investigated for colonies kept for 7 days in MEA medium at 25 degree C. Inactivation was found to occur for all colonies irradiated with 5 kGy and for none irradiated with 2.0 kGy or less. Also investigated was the time needed for irradiated colonies to resume growth. The impact of irradiation on the morphological and microscopic characteristics of the fungus were found to become significant at doses above 1 kGy, causing some structures to gradually shrink or even vanish with increasing dose. (author)

  1. Aspergillus Monitoring Project in a Large Educational Hospital ...

    African Journals Online (AJOL)

    Also molecular method, PCR-RFLP using single restriction enzyme as a rapid and available method was performed to investigate environmental sources of Aspergillus infections. Results: Total of 110 clinical fungal isolates included Candida and Aspergillus species and some other opportunistic fungi. Among the clinical

  2. Characteristics of culture-positive invasive pulmonary aspergillosis in patients with hematologic diseases: Comparison between Aspergillus fumigatus and non-fumigatus Aspergillus species.

    Science.gov (United States)

    Cho, Sung-Yeon; Lee, Dong-Gun; Choi, Jae-Ki; Lee, Hyo-Jin; Kim, Si-Hyun; Park, Sun Hee; Choi, Su-Mi; Choi, Jung-Hyun; Yoo, Jin-Hong; Park, Yeon-Joon; Lee, Jong-Wook

    2017-12-01

    While the epidemiology and clinical differences of various Candida spp. has been relatively well-identified, data regarding invasive aspergillosis (IA) caused by different Aspergillus spp. are insufficient.We aimed to determine the epidemiology of culture-positive invasive pulmonary aspergillosis (IPA) and to compare the characteristics and outcomes of Aspergillus fumigatus IPA with those of non-fumigatus IPA in patients with hematologic diseases. All consecutive cases of IPA from 2011 to 2015 were reviewed retrospectively.There were 430 proven/probable IPA and 76 culture-positive proven/probable IPA. Excluding cases of multiple species of fungi or cases having difficulties in species-level identification, 41 A fumigatus and 22 non-fumigatus IPA (Aspergillus flavus [n = 11], Aspergillus niger [n = 6], and Aspergillus terreus [n = 5]) were compared. There were no significant differences in baseline characteristics between the 2 groups. However, disseminated IA was more common in non-fumigatus IPA (2.4% vs 18.2%; P = .046). Paranasal sinus (PNS) involvement was more common in non-fumigatus IPA. There was a trend towards higher peak serum galactomannan values in non-fumigatus IPA than in A fumigatus IPA group (median 1.33 [interquartile 0.98-3.29] vs 0.97 [0.66-1.97]; P = .084). Clinical response and mortality did not differ between groups.The culture-positive rate of proven/probable IPA was 17.7%, of which non-fumigatus Aspergillus accounted for about one-third. Disseminated IA, especially involving the PNS, was more frequent in non-fumigatus IPA than in A fumigatus IPA.

  3. Cowpeas as growth substrate do not support the production of aflatoxinby Aspergillus sp

    DEFF Research Database (Denmark)

    Houssou, P.A.; Schnidt-Heydt, M.; Geisen, R.

    2008-01-01

    A number of 21 Aspergillus sp. strains isolated from cowpeas from Benin (Africa) were characterizedby RAPD methodology. Seven of these strains grouped with A. flavus in the dendrogram generated with the RAPD data. Only three were able to produce aflatoxin in significant amounts. Twelve other...... produced high amounts of aflatoxin after growth on YES medium. However after growth on cowpea based medium aflatoxin biosynthesis was strongly ceased, albeit the growth of the colony was only partly reduced. This was true for media made either with the whole cowpea seed or with cowpea seed without seed...... coat. Interestingly when the cowpea medium was heat sterilized the fungus was able to produce high amounts of aflatoxin. This, however, was not the case after the use of gamma irradiation as sterilization method for the medium. The expression of the nor-1 gene, which is one of the early genes involved...

  4. Identification and Characterization of an Antifungal Protein, AfAFPR9, Produced by Marine-Derived Aspergillus fumigatus R9.

    Science.gov (United States)

    Rao, Qi; Guo, Wenbin; Chen, Xinhua

    2015-05-01

    A fungal strain, R9, was isolated from the South Atlantic sediment sample and identified as Aspergillus fumigatus. An antifungal protein, AfAFPR9, was purified from the culture supernatant of Aspergillus fumigatus R9. AfAFPR9 was identified to be restrictocin, which is a member of the ribosome-inactivating proteins (RIPs), by MALDI-TOF-TOF-MS. AfAFPR9 displayed antifungal activity against plant pathogenic Fusarium oxysporum, Alternaria longipes, Colletotrichum gloeosporioides, Paecilomyces variotii, and Trichoderma viride at minimum inhibitory concentrations of 0.6, 0.6, 1.2, 1.2, and 2.4 μg/disc, respectively. Moreover, AfAFPR9 exhibited a certain extent of thermostability, and metal ion and denaturant tolerance. The iodoacetamide assay showed that the disulfide bridge in AfAFPR9 was indispensable for its antifungal action. The cDNA encoding for AfAFPR9 was cloned from A. fumigatus R9 by RTPCR and heterologously expressed in E. coli. The recombinant AfAFPR9 protein exhibited obvious antifungal activity against C. gloeosporioides, T. viride, and A. longipes. These results reveal the antifungal properties of a RIP member (AfAFPR9) from marine-derived Aspergillus fumigatus and indicated its potential application in controlling plant pathogenic fungi.

  5. The Platelia Aspergillus ELISA in diagnosis of invasive pulmonary aspergilosis (IPA).

    Science.gov (United States)

    Siemann, M; Koch-Dörfler, M

    2001-01-01

    The sensitivity of a sandwich enzyme-linked immunosorbent assay (ELISA) for detecting Aspergillus galactomannan was evaluated with 66 serum samples and 113 specimens of the respiratory tract obtained from 52 patients with pulmonary diseases. The patients were divided into five groups: proven invasive pulmonary aspergillosis (IPA) (five patients), probable IPA (seven patients), Aspergillus colonization (eight patients) or unlikely Aspergillus infection (27 patients). Another five patients with doubtful diagnostic test results are discussed in detail. The results of the Platelia Aspergillus ELISA (Sanofi Pasteur, Freiburg, Germany) in testing specimens of the respiratory tract were 90% sensitivity in proven (serum 38%), 60% in probable (serum 37%) and 71% in Aspergillus colonization (serum 0%). Furthermore, 85% of the Aspergillus spp. from positive cultures of specimens of the respiratory tract were also detected in the ELISA. A total of 57% of the culture negative specimens of patients with a least one positive culture or proven aspergillosis in a series of specimens were positive in the ELISA.

  6. Sol-gel immobilization as a suitable technique for enhancement of α-amylase activity of Aspergillus oryzae PP.

    Science.gov (United States)

    Evstatieva, Yana; Yordanova, Mariya; Chernev, Georgi; Ruseva, Yanislava; Nikolova, Dilyana

    2014-07-04

    Bioencapsulation of microbial cells in silica-based matrices has proved to be a good strategy to enhance the biosynthetic capabilities and viability of bioproducers. In the present study, mycelium and pellet cultures of strain Aspergillus oryzae PP were successfully immobilized in sol-gel hybrid matrices composed of tetraethylorthosilicate as an inorganic precursor, 5% (w/v) starch and 10 or 15% (w/v) polyethylene oxide, or 10% (w/v) calcium alginate as organic compounds. Biosynthetic activity of immobilized cultures was investigated by batch and fed-batch cultivation and the obtained results of 3042.04 IU cm -3 were comparable with the enzyme activity of the free cell culture. Immobilized cultures retained their viability and biosynthetic capabilities up to the 744th h during fed-batch fermentation processes. Consequently, sol-gel encapsulation in hybrid matrices could be considered as a promising technique for immobilization of Aspergillus oryzae PP in order to increase the α-amylase production.

  7. Aspergillus thyroiditis in a renal transplant recipient mimicking subacute thyroiditis.

    Science.gov (United States)

    Solak, Y; Atalay, H; Nar, A; Ozbek, O; Turkmen, K; Erekul, S; Turk, S

    2011-04-01

    Fungal pathogens are increasingly encountered after renal transplantation. Aspergillus causes significant morbidity and mortality in transplant patients. Fungal thyroiditis is a rare occurrence owing to unique features of the thyroid gland. Most cases are caused by Aspergillus species and have been described in immunocompromised patients. Presentation may be identical with that of subacute thyroiditis, in which hyperthyroidism features and painful thyroid are the prominent findings. Diagnosis can be ascertained by fine-needle aspiration of thyroid showing branching hyphae of Aspergillus. We describe a renal transplant patient who developed Aspergillus thyroiditis as part of a disseminated infection successfully treated with voriconazole. © 2010 John Wiley & Sons A/S.

  8. Aflatoxin B1 inhibition in Aspergillus flavus by Aspergillus niger through down-regulating expression of major biosynthetic genes and AFB1 degradation by atoxigenic A. flavus.

    Science.gov (United States)

    Xing, Fuguo; Wang, Limin; Liu, Xiao; Selvaraj, Jonathan Nimal; Wang, Yan; Zhao, Yueju; Liu, Yang

    2017-09-01

    Twenty Aspergillus niger strains were isolated from peanuts and 14 strains were able to completely inhibit AFB 1 production with co-cultivation. By using a Spin-X centrifuge system, it was confirmed that there are some soluble signal molecules or antibiotics involved in the inhibition by A. niger, although they are absent during the initial 24h of A. flavus growth when it is sensitive to inhibition. In A. flavus, 19 of 20 aflatoxin biosynthetic genes were down-regulated by A. niger. Importantly, the expression of aflS was significantly down-regulated, resulting in a reduction of AflS/AflR ratio. The results suggest that A. niger could directly inhibit AFB 1 biosynthesis through reducing the abundance of aflS to aflR mRNAs. Interestingly, atoxigenic A. flavus JZ2 and GZ15 effectively degrade AFB 1 . Two new metabolites were identified and the key toxic lactone and furofuran rings both were destroyed and hydrogenated, meaning that lactonase and reductase might be involved in the degradation process. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Probiotic attributes of autochthonous Lactobacillus rhamnosus strains of human origin.

    Science.gov (United States)

    Pithva, Sheetal; Shekh, Satyamitra; Dave, Jayantilal; Vyas, Bharatkumar Rajiv Manuel

    2014-05-01

    The study was aimed at evaluating the probiotic potential of indigenous autochthonous Lactobacillus rhamnosus strains isolated from infant feces and vaginal mucosa of healthy female. The survival of the selected strains and the two reference strains (L. rhamnosus GG and L. casei Actimel) was 67-81 % at pH 2 and 70-80 % after passage through the simulated gastrointestinal fluid. These strains are able to grow in the presence of 4 % bile salt, 10 % NaCl, and 0.6 % phenol. The cell surface of L. rhamnosus strains is hydrophilic in nature as revealed by bacterial adhesion to hydrocarbons (BATH) assay. Despite this, L. rhamnosus strains showed mucin adherence, autoaggregation and coaggregation properties that are strain-specific. In addition, they produce bile salt hydrolase (BSH) and β-galactosidase activities. L. rhamnosus strains exhibit antimicrobial activity against food spoilage organisms and gastrointestinal pathogens, as well as Candida and Aspergillus spp. L. rhamnosus strains have similar antibiotic susceptibility pattern, and resistance to certain antibiotics is intrinsic or innate. The strains are neither haemolytic nor producer of biogenic amines such as histamine, putrescine, cadaverine and tyramine. Lyophilized cells of L. rhamnosus Fb exhibited probiotic properties demonstrating potential of the strain for technological suitability and in the preparation of diverse probiotic food formulations.

  10. Aspergillus Species and Their Associated Mycotoxins.

    Science.gov (United States)

    Perrone, Giancarlo; Gallo, Antonia

    2017-01-01

    The genus Aspergillus is among the most abundant and widely distributed organism on earth, and at the moment comprises 339 known species. It is one of the most important economically fungal genus and the biotechnological use of Aspergillus species is related to production of soy sauce, of different hydrolytic enzymes (amylases, lipases) and organic acid (citric acid, gluconic acid), as well as biologically active metabolites such as lovastatin. Although they are not considered to be major cause of plant diseases, Aspergillus species are responsible for several disorders in various plants and plant products, especially as opportunistic storage moulds. The notable consequence of their presence is contamination of foods and feeds by mycotoxins, among which the most important are aflatoxins, ochratoxin A, and, at a less extent, fumonisins. Aflatoxins B 1 , B 2 , G 1 , G 2 are the most toxic and carcinogenic mycotoxins, due to their extreme hepatocarcinogenicity; ochratoxin A is a potent nephrotoxin, it is also carcinogenic, teratogenic, and immunotoxic in rats and possibly in humans; fumonisins are hepatotoxic and nephrotoxic with potential carcinogenic effects on rat and mice. In this chapter we summarize the main aspects of morphology, ecology, epidemiology, and toxigenicity of Aspergillus foodborne pathogens which belong to sections Flavi, Circumdati, and Nigri, occurring in several agricultural products and responsible of aflatoxin, ochratoxin A, and fumonisins contamination of food and feed.

  11. Biodiversity of Aspergillus species in some important agricultural products

    DEFF Research Database (Denmark)

    Perrone, Giancarlo; Susca, A.,; Cozzi, G.

    2007-01-01

    The genus Aspergillus is one of the most important filamentous fungal genera. Aspergillus species are used in the fermentation industry, but they are also responsible of various plant and food secondary rot, with the consequence of possible accumulation of mycotoxins. The aflatoxin producing A....... flavus and A. parasiticus, and ochratoxinogenic A. niger, A. ochraceus and A. carbonarius species are frequently encountered in agricultural products. Studies on the biodiversity of toxigenic Aspergillus species is useful to clarify molecular, ecological and biochemical characteristics of the different...... occurring in agricultural fields. Altogether nine different black Aspergillus species can be found on grapes which are often difficult to identify with classical methods. The polyphasic approach used in our studies led to the identification of three new species occurring on grapes: A. brasiliensis, A...

  12. Isotherm studies for determination of removal capacity of bi-metal (Ni and Cr) ions by aspergillus niger

    International Nuclear Information System (INIS)

    Munir, K.; Yusuf, M.; Hameed, A.; Noreen, Z.; Hafeez, F.Y.; Faryal, R.

    2010-01-01

    Pakistan is among the developing countries where there is a need to establish new industries to meet the demands of a growing population. This has led to industrial setup in various sectors, without proper planning and consideration for treatment of contamination, leading to disposal of untreated wastewater into nearby land and water bodies. This study was planned to investigate an indigenous Aspergillus niger for development of biosorbent for the removal of metal ions. The Aspergillus isolate's Ni and Cr removal efficiency was determined in batch mode over various pH (4.0-10.0) and temperature (25-40 deg. C) as single as well as bimetal ions. Using a single metal ion, maximum biosorption potential was obtained at pH 5.0-6.0 and 30-35 deg. C for both ions. On the other hand, Ni removal was reduced in the presence of Cr, while Ni removal influenced Cr removal with an increase showing maximum removal at an initial adsorbate concentration of 50mg/L, pH 6.0 and 35 deg. C. Effect of presence of bimetal in a solution on biosorption potential of Aspergillus niger was predicted by using equilibrium modeling. Adsorption trends for both nickel (R2 0.9916) and chromium (R2 0.8548) followed Langmuir isotherm in single metal removal system, but under bimetal condition chromium adsorption fitted better to Freundlich model and that of nickel followed Temkin isotherm, suggesting considerable change in behavior and interaction between biosorbent and metal ions. Therefore, we concluded that Aspergillus niger a viable strain for development of a biosorbent for removal of a mixture of metal ions. (author)

  13. Localization of functional β-xylosidases, encoded by the same single gene, xlsIV (xlnD), from Aspergillus niger E-1.

    Science.gov (United States)

    Inoue, Kotomi; Takahashi, Yui; Obara, Ken; Murakami, Shuichiro

    2017-03-01

    Cell wall-associated β-xylosidase was isolated from Aspergillus niger E-1 and identified as XlsIV, corresponding to the extracellular enzyme XlnD reported previously. xlsIV was transcribed only in the early cultivation period. Cell wall-associated enzyme activity gradually decreased, but extracellular activity increased as the strain grew. These results indicate that XlsIV (XlnD) was secreted into culture after localizing at cell wall.

  14. Breeding study of hyper citric acid strain by progressive heavy ion irradiation

    International Nuclear Information System (INIS)

    Chen Jihong; Hu Wei; Li Wenjian; Liu Jing; Wang Shuyang; Wei Zihao

    2013-01-01

    Heavy "1"2C"6"+ ion beams in various high doses were employed to irradiate H3001 strain for screening Aspergillus niger strain for hyper citric acid production. Three high-yield strains were obtained after shaker fermentation test. Among the three strains, the strain hw317 was implemented shaker fermentation for stability test and 10∼100 L pilot fermentation tank for citric acid productive maximization. Acid-base neutralization method was applied to determinate the content of citric acid in fermented liquid. The results showed that: when the secondary heavy ion "1"2C"6"+ dose was 857.8 Gy, both of the fatality rate (94.5%) and the positive mutation rate (8%) were highest. Through the shaker fermentation tests and 10∼100 L pilot fermentation test, one strain hw317 was screened and obtained for hyper citric acid production. Consequently, the final citric acid acidity can reach up to 19.2±0.2% with controlling fermentation cycle for 60 h. (authors)

  15. GROWTH AND ENZYME PRODUCTION DURING CONTINUOUS CULTURES OF A HIGH AMYLASE-PRODUCING VARIANT OF Aspergillus Oryzae

    Directory of Open Access Journals (Sweden)

    T.C. Zangirolami

    2002-03-01

    Full Text Available Growth and product formation by a selected variant of Aspergillus oryzae showing high alpha-amylase production was studied in continuous cultivations carried out at six different specific growth rates, using glucose as the growth-limiting nutrient. The analysis of the steady-state data revealed that the variant and wild-type strains were similar with respect to glucose uptake system and stoichiometric coefficients. However, the variant was capable of maintaining an enzyme production as high as 40 FAUgDW-1h-1 at a dilution rate of 0.2 h-1, while the wild-type strain reached a maximum specific alpha-amylase production rate of 17 FAUgDW-1h-1 at a dilution rate of 0.1 h-1. Using a morphologically structured model originally proposed for the wild-type strain, it was possible to describe enzyme production, biomass formation and glucose consumption after modification of a few parameters to adjust the model to the characteristics of the selected variant.

  16. [Utility of Aspergillus-LFD: first experience in Chile].

    Science.gov (United States)

    Alvarez, Eduardo

    2015-02-01

    The diagnosis of invasive aspergillosis remains a challenge. Detection of galactomannan in serum and bronchoalveolar lavage is a useful tool; however due to methodological and economic reasons, the test frequencies of galactomannan assays vary from daily to weekly, which constitute a risk to the patient. In this study, we aimed to evaluate and correlate the performance of the new kit Aspergillus-LFD with the GM-EIA. Aspergillus-LFD kit represents a fast, economical and simple test; showed a good performance and excellent correlation with GM-EIA kit. Given the above, the Aspergillus-LFD is emerging as an alternative to consider in the early diagnosis of invasive aspergillosis.

  17. Aspergillus in the lung: diverse and coincident forms

    International Nuclear Information System (INIS)

    Buckingham, Susan J.; Hansell, David M.

    2003-01-01

    Pulmonary disease caused by the fungus Aspergillus has traditionally been regarded as belonging to one of the following, apparently distinct, entities: saprophytic aspergilloma; allergic bronchopulmonary aspergillosis (ABPA); and invasive aspergillosis (IPA); which may be further categorised as angioinvasive, acute or chronic airway invasive [1]. It is not always obvious that there is overlap between these entities, and that in any given patient more than one Aspergillus-related pathological process can co-exist [2]. The aim of this article is to review the clinical and imaging features of the main categories of Aspergillus-related pulmonary disease and, in particular, to highlight the overlap between them. (orig.)

  18. Efficient formation of heterokaryotic sclerotia in the filamentous fungus Aspergillus oryzae.

    Science.gov (United States)

    Wada, Ryuta; Jin, Feng Jie; Koyama, Yasuji; Maruyama, Jun-ichi; Kitamoto, Katsuhiko

    2014-01-01

    Heterokaryon formation by hyphal fusion occurs during a sexual/parasexual cycle in filamentous fungi, and therefore, it is biotechnologically important for crossbreeding. In the industrial filamentous fungus Aspergillus oryzae, a parasexual cycle has been reported, and it was recently suggested that sexual reproduction should be possible. However, as A. oryzae enters into hyphal fusion with a much lower frequency than Neurospora crassa, the process of heterokaryon formation has not been extensively characterized in A. oryzae. Here, we developed a detection system for heterokaryon formation by expressing red or green fluorescent proteins in nuclei and conferring uridine/uracil or adenine auxotrophy to MAT1-1 and MAT1-2 strains of A. oryzae. The heterokaryon formation of A. oryzae was investigated in paired culture using the genetically modified strains. No sclerotial formation was observed in the hyphal contact regions of the two strains with the same auxotrophy, whereas numerous sclerotia were formed between the strains with different auxotrophies. In most of the formed sclerotia, the uridine/uracil and adenine auxotrophies were complemented, and both red and green fluorescence were detected, indicating that heterokaryotic fusants were formed by hyphal fusion before or during sclerotial formation. Moreover, overexpressing the sclR gene, which encodes a transcription factor promoting sclerotial formation, increased the number of heterokaryotic sclerotia formed between the two auxotrophic strains. Notably, these effects in sclerotial formation of heterokaryotic fusants were observed independently of the mating type pairing combinations. Taken together, these findings demonstrated that paring of different auxotrophs and sclR overexpression promote the formation of heterokaryotic sclerotia in A. oryzae.

  19. Optimization of Amylase and Protease Production from Aspergillus awamori in Single Bioreactor Through EVOP Factorial Design Technique

    Directory of Open Access Journals (Sweden)

    Sangeeta Negi

    2006-01-01

    Full Text Available Evolutionary operation (EVOP factorial design technique was explored in order to economically produce amylase and protease at their optimum level in a single bioreactor by modified solid-state fermentation. Maximum yields of amylase and protease were achieved, using wheat bran as a substrate by a highly potent, locally isolated strain of Aspergillus awamori: Nakazawa MTCC 6652. The strain had been induced previously, inferring the ability to produce both enzymes concomitantly in a single bioreactor with their maximum capacity. The highest secretion of amylase and protease were measured to be 9420.6 and 1930 U/g, respectively, at 37 °C. pH and relative humidity were found to be optimum at 4 and 85 %, evaluated through EVOP method.

  20. Phylogeny of osmophillic aspergilli (subgenus Aspergillus) and taxonomic revision of section Restricti

    Science.gov (United States)

    Aspergillus section Restricti together with sister sect. Aspergillus (formerly Eurotium) comprises osmophilic species, that are able to grow on substrates with low water activity and in extreme environments. We addressed the monophyly of both sections within subgenus Aspergillus and applied multidis...

  1. Isolation and optimization of pectinase enzyme production one of useful industrial enzyme in Aspergillus niger, Rhizopus oryzae, Penicilium chrysogenum

    Directory of Open Access Journals (Sweden)

    akram songol

    2016-06-01

    Full Text Available Introduction: Pectinase enzyme is one of the most important industrial enzymes which isolated from a wide variety of microorganisms such as bacteria and filamentous fungi. This enzyme has been usually used in the fruit and textile industry. In this study, the isolation and optimization of pectinase-producing fungi on decaying rotten fruits were studied. Materials and methods: Isolation and screening of pectinase producing fungi performed through plate culture on pectin medium and staining with Lugol's iodine solution. The best strains were identified by ITS1, 4 sequencing as Aspergillus fumigatus, Rhizopus oryzae, Penicilium chrysogenum. The enzyme production was optimized by application of the five factorial design, each at three levels. These factors are carbon sources (whey, glucose and stevia, ammonium sulfate, manganese sulfate, temperature, and pH. Pectinase concentration was measured by the Miller method. Results: The results indicate that optimum condition for enzyme production for three fungi strains was obtained at 32 °C, pH = 6, 3g / L manganese sulfate, 2.75g / L of ammonium sulfate and 10g / L of each carbon source. The best experiment in obtaining the optimum enzyme contained 1.328 mg / ml of glucose for Aspergillus niger 1.284 and 1.039 mg / ml of whey for Rhizopus oryzae and Penicilium chrysogenum. Molecular weight of enzyme was about 40 and 37 kDa which was obtained by SDS- PAGE. Discussion and conclusion: The results indicate that three strains could grow in a wide range of carbon source, pH and temperature, which could be a good candidate for industrial application.

  2. Effect of secretory pathway gene overexpression on secretion of a fluorescent reporter protein in Aspergillus nidulans

    DEFF Research Database (Denmark)

    Schalén, Martin; Anyaogu, Diana Chinyere; Hoof, Jakob Blæsbjerg

    2016-01-01

    roles in the process have been identified through transcriptomics. The assignment of function to these genes has been enabled in combination with gene deletion studies. In this work, 14 genes known to play a role in protein secretion in filamentous fungi were overexpressed in Aspergillus nidulans....... The background strain was a fluorescent reporter secreting mRFP. The overall effect of the overexpressions could thus be easily monitored through fluorescence measurements, while the effects on physiology were determined in batch cultivations and surface growth studies. Results: Fourteen protein secretion...... pathway related genes were overexpressed with a tet-ON promoter in the RFP-secreting reporter strain and macromorphology, physiology and protein secretion were monitored when the secretory genes were induced. Overexpression of several of the chosen genes was shown to cause anomalies on growth, micro...

  3. Dynamic Fumonisin B₂ Production by Aspergillus niger Intented Used in Food Industry in China.

    Science.gov (United States)

    Han, Xiaomin; Jiang, Hongru; Xu, Jin; Zhang, Jing; Li, Fengqin

    2017-07-09

    There are a total of 30 strains including 27 strains of Aspergillus niger intended used in Chinese food industry, two strains used as control and one strain isolated from corn for fumonisin (FB) production on 3 media. It was found that FB₂ production by A. niger was function-dependent and highly related to culture media, as well as incubation time. All strains studied were unable to produce FB₁ and FB₃. Almost all strains were found to produce FB₂ on corn, rice and wheat bran. Based on their intended use in the food industry, the higher level of FB₂ producers were strains used for saccharifying enzyme ( n = 13) production, followed by organic acid ( n = 6), tannase ( n = 7) and β-galactosidase ( n = 1) production, with the FB₂ mean level of 3553-10,270 μg/kg, 1059-12,036 μg/kg, 3-7 μg/kg and 2-4 μg/kg on corn, 5455-9241 μg/kg, 559-2190 μg/kg, 4-9 μg/kg and 6-10 μg/kg on rice, 5959-7709 μg/kg, 9491-17,339 μg/kg, 8-14 μg/kg and 120-222 μg/kg on wheat bran, respectively. Comparatively, strains of Fusarium verticillioide were capable of producing fumonins simultaneously with broader spectrum including FB₁, FB₂ and FB₃, but at a much lower level. In conclusion, it is necessary to evaluate FB₂ production by A. niger before intended use in the food processing industry.

  4. Aflatoxin B1 Detoxification by Aspergillus oryzae from Meju, a Traditional Korean Fermented Soybean Starter.

    Science.gov (United States)

    Lee, Kyu Ri; Yang, Sun Min; Cho, Sung Min; Kim, Myunghee; Hong, Sung-Yong; Chung, Soo Hyun

    2016-11-04

    Aflatoxins are classified as Group 1 (carcinogenic to humans) by the International Agency for Research on Cancer (IARC). In this study, a total of 134 fungal strains were isolated from 65 meju samples, and two fungal isolates were selected as potential aflatoxin B₁ (AFB₁)-biodetoxification fungi. These fungi were identified as Aspergillus oryzae MAO103 and A. oryzae MAO104 by sequencing the beta-tubulin gene. The two A. oryzae strains were able to degrade more than 90% of AFB1 (initial concentration: 40 µg/L) in a culture broth in 14 days. The mutagenic effects of AFB₁ treated with A. oryzae MAO103 and MAO104 significantly decreased to 5.7% and 6.4%, respectively, in the frame-shift mutation of Ames tests using Salmonella typhimurium TA 98. The base-substituting mutagenicity of AFB₁ was also decreased by the two fungi. Moreover, AFB1 production by A. flavus was significantly decreased by the two A. oryzae strains on soybean-based agar plates. Our data suggest that the two AFB1-detoxification A. oryzae strains have potential application to control AFB₁ in foods and feeds.

  5. Production and partial characterization of polygalacturonases produced by thermophilic Monascus sp N8 and by thermotolerant Aspergillus sp N12 on solid-state fermentation Produção e caracterização parcial de poligalacturonases produzidas pelo fungo termofílico Monascus sp N8 e pelo termotolerante Aspergillus sp N12 em fermentação em estado sólido

    Directory of Open Access Journals (Sweden)

    Paula Mendes de Freitas

    2006-09-01

    Full Text Available Polygalacturonases production by newly isolated Monascus sp N8 and Aspergillus sp N12 strains was carried out in solid-state fermentation using mixtures of wheat bran, sugar cane bagasse and orange bagasse as carbon sources. The maximal activity values of exo-polygalacturonases (exo-Pg from Monascus sp and Aspergillus sp were obtained using wheat bran/sugar cane bagasse/orange bagasse mixture (6.6 U/mL and wheat bran/orange bagasse mixture (10 U/mL, respectively. Enzyme production by both strains was higher at 45ºC after 72 h and 1.6 U/mL at 50ºC after 120 h. Endo-polygalacturonase (endo-Pg production was higher in wheat bran/orange bagasse mixture and was not affected by temperature of incubation for both fungi. Endo-Pg production by Monascus was 1.8 U/mL at 45ºC and 50ºC, after 72. Similar values were obtained in Aspergillus sp culture, 1.9 U/mL at 45ºC and 1.8 U/mL at 50ºC. Exo-Pg from both strains showed optimum activity at pH 5.5. Maximal activity was determined at 60ºC for enzyme from Monascus sp and 50ºC for that produced by Aspergillus sp. Exo-Pg from Monascus sp was stable at pH range 4.5-6.0 whereas that from Aspergillus sp enzyme was stable at pH 4.0. Both enzymes showed stability when incubated at 50ºC for 1 h, in absence of substrate.A produção de poligalacturonases pelas linhagens fúngicas recentemente isoladas, Monascus sp N8 e Aspergillus sp N12, foi estudada através de fermentação em estado sólido usando como substratos misturas de farelo de trigo, bagaço da cana-de-açúcar e bagaço de laranja. A atividade máxima de exo-Pg produzida por Monascus sp (6,6 U/mL foi obtida quando o meio de cultivo utilizado continha mistura de farelo de trigo, bagaço da cana-de-açúcar e bagaço de laranja (1:1:1, enquanto que Aspergillus sp produziu maior quantidade da enzima (10 U/mL em meio de farelo de trigo e bagaço de laranja. A maior produção de exo-Pg foi obtida através de incubação das culturas a 45ºC quando

  6. L-lactic acid production from starch by simultaneous saccharification and fermentation in a genetically engineered Aspergillus oryzae pure culture.

    Science.gov (United States)

    Wakai, Satoshi; Yoshie, Toshihide; Asai-Nakashima, Nanami; Yamada, Ryosuke; Ogino, Chiaki; Tsutsumi, Hiroko; Hata, Yoji; Kondo, Akihiko

    2014-12-01

    Lactic acid is a commodity chemical that can be produced biologically. Lactic acid-producing Aspergillus oryzae strains were constructed by genetic engineering. The A. oryzae LDH strain with the bovine L-lactate dehydrogenase gene produced 38 g/L of lactate from 100g/L of glucose. Disruption of the wild-type lactate dehydrogenase gene in A. oryzae LDH improved lactate production. The resulting strain A. oryzae LDHΔ871 produced 49 g/L of lactate from 100g/L of glucose. Because A. oryzae strains innately secrete amylases, A. oryzae LDHΔ871 produced approximately 30 g/L of lactate from various starches, dextrin, or maltose (all at 100 g/L). To our knowledge, this is the first report describing the simultaneous saccharification and fermentation of lactate from starch using a pure culture of transgenic A. oryzae. Our results indicate that A. oryzae could be a promising host for the bioproduction of useful compounds such as lactic acid. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Biosynthesis of cellulolytic enzymes by Aspergillus niger A. n. 33 and its selectants

    Energy Technology Data Exchange (ETDEWEB)

    Czajkowska, D.; Hornecka, D.; Ilnicka-Olejniczak, O.

    1988-01-01

    The aim of the investigations was to obtain - from the parent strain Aspergillus niger A.n. 33 - selectants with an increased ability of cellulolytic enzymes biosynthesis. Own selection methods allowed to receive two selectants A.n. 33/2 and A.n. 33/20 characterized by enhanced activities of saccharifying cellulase (respectively 0.11 and 0.14 FPU/cm/sup 3/), endo-beta-1,4-glucanase (15.4 and 21.8 U/cm/sup 3/) and cellobiase (0.6 and 1.4 IU/cm/sup 3/) as compared with the parent strain (FPA - 0.09 IU, CMC - 8.2 U and CB - 0.1 IU/cm/sup 3/). Moreover, the selectants differed in shape and size of conidial heads, in shape and colour of conidia, as well as in structure and shape of hyphase. Enzyme preparations obtained after ultrafiltration of liquid cultures were characterized by following activities: FPA-4-16 IU, CMC-900-1800 U, CB-60-120 IU and xylanase-250-280 IU/cm/sup 3/.

  8. Microalgae Harvest through Fungal Pelletization—Co-Culture of Chlorella vulgaris and Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Sarman Oktovianus Gultom

    2014-07-01

    Full Text Available Microalgae harvesting is a labor- and energy-intensive process and new approaches to harvesting microalgae need to be developed in order to decrease the costs. In this study; co-cultivatation of filamentous fungus (Aspergillus niger and microalgae (Chlorella vulgaris to form cell pellets was evaluated under different conditions, including organic carbon source (glucose; glycerol; and sodium acetate concentration; initial concentration of fungal spores and microalgal cells and light. Results showed that 2 g/L of glucose with a 1:300 ratio of fungi to microalgae provided the best culturing conditions for the process to reach >90% of cell harvest efficiency. The results also showed that an organic carbon source was required to sustain the growth of fungi and form the cell pellets. The microalgae/fungi co-cultures at mixotrophic conditions obtained much higher total biomass than pure cultures of each individual strains; indicating the symbiotic relationship between two strains. This can benefit the microbial biofuel production in terms of cell harvest and biomass production.

  9. Use of Aspergillus niger for bioconversion of apple distillery waste

    Energy Technology Data Exchange (ETDEWEB)

    Friedrich, J.; Cimerman, A.; Perdih, A.

    1983-01-01

    The bioconversion of waste material remaining after apple brandy distillation was investigated. Different cellulolytic fungi were tested for their ability to convert the waste organic substances into microbial biomass. An Aspergillus niger strain was chosen as the most convenient microorganism. By growing this mold on the apple slop the following results were obtained: filtration time was shortened by 30 times, reduction of the chemical oxygen demand in the liquid phase in the range of 50-80% depending on the substrate dilution and a dry filter cake enriched with fungal biomass to about 12 g/l containing up to 22% raw proteins and certain amounts of cellulolytic enzymes in the filtrate. The influence of the initial pH, the salt addition and the dilution of the substrate were studied as well. 12 references.

  10. Analysis and prediction of gene splice sites in four Aspergillus genomes

    DEFF Research Database (Denmark)

    Wang, Kai; Ussery, David; Brunak, Søren

    2009-01-01

    Several Aspergillus fungal genomic sequences have been published, with many more in progress. Obviously, it is essential to have high-quality, consistently annotated sets of proteins from each of the genomes, in order to make meaningful comparisons. We have developed a dedicated, publicly available......, splice site prediction program called NetAspGene, for the genus Aspergillus. Gene sequences from Aspergillus fumigatus, the most common mould pathogen, were used to build and test our model. Compared to many animals and plants, Aspergillus contains smaller introns; thus we have applied a larger window...... better splice site prediction than other available tools. NetAspGene will be very helpful for the study in Aspergillus splice sites and especially in alternative splicing. A webpage for NetAspGene is publicly available at http://www.cbs.dtu.dk/services/NetAspGene....

  11. Hydroxylative activity of Aspergillus niger towards androst-4-ene and androst-5-ene steroids.

    Science.gov (United States)

    Świzdor, Alina; Panek, Anna; Milecka-Tronina, Natalia

    2017-10-01

    Aspergillus niger, one of fungal species most frequently used for experimental and industrial-scale biotransformations of various organic compounds, is generally known to transform steroids at 16β position. In this work, application of the strain A. niger KCH910 to bioconversion of dehydroepiandrosterone (DHEA), androstenediol and testosterone is described, with emphasis on the metabolic steps leading to the products. Evidence from this study indicated that incubated 5-ene steroids underwent bioconversion within two metabolic pathways: oxidation by the action of 3β-HSD (3β-hydroxysteroid dehydrogenase) to 4-ene steroids, and minor allylic hydroxylation to epimeric 7-alcohols. Further transformation of the 3-oxo-4-ene metabolites resulted in non-selective 16-hydroxylation. It is the first report on an A. niger strain able to introduce not only 16β- but also 16α-hydroxyl function into steroids. Copyright © 2017. Published by Elsevier Inc.

  12. Chitin Synthases with a Myosin Motor-Like Domain Control the Resistance of Aspergillus fumigatus to Echinocandins

    Science.gov (United States)

    Jiménez-Ortigosa, Cristina; Aimanianda, Vishukumar; Muszkieta, Laetitia; Mouyna, Isabelle; Alsteens, David; Pire, Stéphane; Beau, Remi; Krappmann, Sven; Beauvais, Anne; Dufrêne, Yves F.

    2012-01-01

    Aspergillus fumigatus has two chitin synthases (CSMA and CSMB) with a myosin motor-like domain (MMD) arranged in a head-to-head configuration. To understand the function of these chitin synthases, single and double csm mutant strains were constructed and analyzed. Although there was a slight reduction in mycelial growth of the mutants, the total chitin synthase activity and the cell wall chitin content were similar in the mycelium of all of the mutants and the parental strain. In the conidia, chitin content in the ΔcsmA strain cell wall was less than half the amount found in the parental strain. In contrast, the ΔcsmB mutant strain and, unexpectedly, the ΔcsmA/ΔcsmB mutant strain did not show any modification of chitin content in their conidial cell walls. In contrast to the hydrophobic conidia of the parental strain, conidia of all of the csm mutants were hydrophilic due to the presence of an amorphous material covering the hydrophobic surface-rodlet layer. The deletion of CSM genes also resulted in an increased susceptibility of resting and germinating conidia to echinocandins. These results show that the deletion of the CSMA and CSMB genes induced a significant disorganization of the cell wall structure, even though they contribute only weakly to the overall cell wall chitin synthesis. PMID:22964252

  13. Exact Molecular Typing of Aspergillus fumigatus. Methods and Applications.

    NARCIS (Netherlands)

    Valk-van Haren, J.A. de

    2008-01-01

    Aspergillus species are widely distributed fungi that release large amounts of airborne conidia that are dispersed in the environment. Aspergillus fumigatus is the species most frequently isolated from human infections. In this thesis a novel assay for fingerprinting A. fumigatus is described and

  14. The FlbA-regulated predicted transcription factor Fum21 of Aspergillus niger is involved in fumonisin production.

    Science.gov (United States)

    Aerts, David; Hauer, Esther E; Ohm, Robin A; Arentshorst, Mark; Teertstra, Wieke R; Phippen, Christopher; Ram, Arthur F J; Frisvad, Jens C; Wösten, Han A B

    2018-03-01

    Aspergillus niger secretes proteins throughout the colony except for the zone that forms asexual spores called conidia. Inactivation of flbA that encodes a regulator of G-protein signaling results in colonies that are unable to reproduce asexually and that secrete proteins throughout the mycelium. In addition, the ΔflbA strain shows cell lysis and has thinner cell walls. Expression analysis showed that 38 predicted transcription factor genes are differentially expressed in strain ΔflbA. Here, the most down-regulated predicted transcription factor gene, called fum21, was inactivated. Growth, conidiation, and protein secretion were not affected in strain Δfum21. Whole genome expression analysis revealed that 63 and 11 genes were down- and up-regulated in Δfum21, respectively, when compared to the wild-type strain. Notably, 24 genes predicted to be involved in secondary metabolism were down-regulated in Δfum21, including 10 out of 12 genes of the fumonisin cluster. This was accompanied by absence of fumonisin production in the deletion strain and a 25% reduction in production of pyranonigrin A. Together, these results link FlbA-mediated sporulation-inhibited secretion with mycotoxin production.

  15. Aspergillus triggers phenazine production in Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Jensen, Britt Guillaume; Jelsbak, Lars; Søndergaard, Ib

    in the contact area of A. niger, A. flavus, A. oryzae, but not A. fumigatus. In addition, other metabolites with UV chromophores similar to the phenazines were only found in the contact zone between Aspergillus and Pseudomonas. No change in secondary metabolite profiles were seen for the Aspergilli, when......Objectives: Pseudomonas aeruginosa is an opportunistic human pathogen, commonly infecting cystic fibrosis (CF) patients. Aspergilli, especially Aspergillus fumigatus, are also frequently isolated from CF patients. Our aim was to examine the possible interaction between P. aeruginosa and different...... Aspergillus species. Methods: A suspension of fungal spores was streaked onto WATM agar plates. After 24 hours incubation at 37 °C, a P. aeruginosa overnight culture was streaked out perpendicular to the fungal streak. The plates were incubated at 37 °C for five days, examined and plugs were extracted...

  16. Biosorption of Cu (II onto chemically modified waste mycelium of Aspergillus awamori: Equilibrium, kinetics and modeling studies

    Directory of Open Access Journals (Sweden)

    ZDRAVKA VELKOVA

    2012-01-01

    Full Text Available The biosorption potential of chemically modified waste mycelium of industrial xylanase-producing strain Aspergillus awamori for Cu (II removal from aqueous solutions was evaluated. The influence of pH, contact time and initial Cu (II concentration on the removal efficiency was evaluated. Maximum biosorption capacity was reached by sodium hydroxide treated waste fungal mycelium at pH 5.0. The Langmuir adsorption equation matched very well the adsorption equilibrium data in the studied conditions. The process kinetic followed the pseudo-firs order model.

  17. Terbinafine Resistance Mediated by Salicylate 1-Monooxygenase in Aspergillus nidulans

    Science.gov (United States)

    Graminha, Marcia A. S.; Rocha, Eleusa M. F.; Prade, Rolf A.; Martinez-Rossi, Nilce M.

    2004-01-01

    Resistance to antifungal agents is a recurring and growing problem among patients with systemic fungal infections. UV-induced Aspergillus nidulans mutants resistant to terbinafine have been identified, and we report here the characterization of one such gene. A sib-selected, 6.6-kb genomic DNA fragment encodes a salicylate 1-monooxygenase (salA), and a fatty acid synthase subunit (fasC) confers terbinafine resistance upon transformation of a sensitive strain. Subfragments carrying salA but not fasC confer terbinafine resistance. salA is present as a single-copy gene on chromosome VI and encodes a protein of 473 amino acids that is homologous to salicylate 1-monooxygenase, a well-characterized naphthalene-degrading enzyme in bacteria. salA transcript accumulation analysis showed terbinafine-dependent induction in the wild type and the UV-induced mutant Terb7, as well as overexpression in a strain containing the salA subgenomic DNA fragment, probably due to the multicopy effect caused by the transformation event. Additional naphthalene degradation enzyme-coding genes are present in fungal genomes, suggesting that resistance could follow degradation of the naphthalene ring contained in terbinafine. PMID:15328121

  18. Glucose uptake and growth of glucose-limited chemostat cultures of Aspergillus niger and a disruptant lacking MstA, a high-affinity glucose transporter

    DEFF Research Database (Denmark)

    Jørgensen, Thomas R; vanKuyk, Patricia A; Poulsen, Bjarne R

    2007-01-01

    This is a study of high-affinity glucose uptake in Aspergillus niger and the effect of disruption of a high-affinity monosaccharide-transporter gene, mstA. The substrate saturation constant (K(s)) of a reference strain was about 15 microM in glucose-limited chemostat culture. Disruption of mst......-affinity uptake system of A. niger. The mstA disruptant and a reference strain were cultivated in glucose-limited chemostat cultures at low, intermediate and high dilution rate (D=0.07 h(-1), 0.14 h(-1) and 0.20 h(-1)). Mycelium harvested from steady-state cultures was subjected to glucose uptake assays...

  19. High-content screening of Aspergillus niger with both increased production and high secretion rate of glucose oxidase.

    Science.gov (United States)

    Zhu, Xudong; Sun, Jingchun; Chu, Ju

    2018-01-01

    To develop a rapid, dual-parameter, plate-based screening process to improve production and secretion rate of glucose oxidase simultaneously in Aspergillus niger. A morphology engineering based on CaCO 3 was implemented, where the yield of GOD by A. niger was increased by up to 50%. Analysis of extracellular GOD activity was achieved in 96-well plates. There was a close negative correlation between the total GOD activity and its residual glucose of the fermentation broth. Based on this, a rapid, plate-based, qualitative analysis method of the total GOD activity was developed. Compared with the conventional analysis method using o-dianisidine, a correlation coefficient of -0.92 by statistical analysis was obtained. Using this dual-parameter screening method, we acquired a strain with GOD activity of 3126 U l -1 , which was 146% higher than the original strain. Its secretion rate of GOD was 83, 32% higher than the original strain.

  20. HisB as novel selection marker for gene targeting approaches in Aspergillus niger.

    Science.gov (United States)

    Fiedler, Markus R M; Gensheimer, Tarek; Kubisch, Christin; Meyer, Vera

    2017-03-08

    For Aspergillus niger, a broad set of auxotrophic and dominant resistance markers is available. However, only few offer targeted modification of a gene of interest into or at a genomic locus of choice, which hampers functional genomics studies. We thus aimed to extend the available set by generating a histidine auxotrophic strain with a characterized hisB locus for targeted gene integration and deletion in A. niger. A histidine-auxotrophic strain was established via disruption of the A. niger hisB gene by using the counterselectable pyrG marker. After curing, a hisB - , pyrG - strain was obtained, which served as recipient strain for further studies. We show here that both hisB orthologs from A. nidulans and A. niger can be used to reestablish histidine prototrophy in this recipient strain. Whereas the hisB gene from A. nidulans was suitable for efficient gene targeting at different loci in A. niger, the hisB gene from A. niger allowed efficient integration of a Tet-on driven luciferase reporter construct at the endogenous non-functional hisB locus. Subsequent analysis of the luciferase activity revealed that the hisB locus is tight under non-inducing conditions and allows even higher luciferase expression levels compared to the pyrG integration locus. Taken together, we provide here an alternative selection marker for A. niger, hisB, which allows efficient homologous integration rates as well as high expression levels which compare favorably to the well-established pyrG selection marker.