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Sample records for aspergillus flavus produtor

  1. Studies on Aspergillus flavus

    International Nuclear Information System (INIS)

    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)

  2. 76 FR 16297 - Aspergillus flavus

    Science.gov (United States)

    2011-03-23

    ... exemptions for experimental use of Aspergillus flavus AF36 on pistachio (72 FR 28871, May 23, 2007) (FRL-8129... Findings In the Federal Register of March 3, 2010 (75 FR 9596) (FRL-8811-2), EPA issued a notice pursuant..., 2003 (68 FR 41541) (FRL-7311-6). Those health effects data were the basis for establishing...

  3. Effect of gamma radiation on the growth of Aspergillus Flavus aflatoxins producer and on the use of polymerase chain reaction technique (PCR) in samples of maize grains artificially inoculated; Efeitos da radiacao gama no crescimento de Aspergillus flavus produtor de aflatoxinas e no emprego da tecnica da Reacao em Cadeia da Polimerase (RCP) em amostras de graos de milho inoculadas artificialmente

    Energy Technology Data Exchange (ETDEWEB)

    Aquino, Simone

    2003-07-01

    The aim of this present study was to verify the effects of gamma radiation on the growth of Aspergillus flavus Link aflatoxins producer; to demonstrate the application of Polymerase Chain Reaction (PCR) technique in the diagnostic of A. Flavus, as well to verify the effect of radiation in the profile of DNA bands. Twenty samples of grains maize with 200 g each were individually irradiated with 20 kGy, to eliminate the microbial contamination. In following, the samples were inoculated with an toxigenic A. flavus (1x10{sup 6} spores/ml), incubated for 15 days at 25 deg C with a relative humidity of around 97,5% and irradiated with 0, 2; 5 and 10 kGy. The samples, 5 to each dose of irradiation, were individually analyzed for the number of fungal cells, water activity, viability test (fluorescein diacetate and ethidium bromide), PCR and aflatoxins (AFB) detection. The results showed that the doses used were effective in reducing the number of Colony Forming Units (CFU/g) mainly the doses of 5 and 10 kGy. In addition, the viability test showed a decrease of viable cells with increase of irradiation doses. The reduction of AFB{sub 1} and AFB-2, was more efficient with the use of 2 kGy in comparison with the dose of 5 kGy, while the dose of 10 kGy, degraded the aflatoxins. Thereby, it was observed that AFB2 showed to be more radiosensitive. The use of PCR technique showed the presence of DNA bands, in all samples. (author)

  4. Nuclear heterogeneity in conidial populations of Aspergillus flavus

    Science.gov (United States)

    Aspergillus flavus is a major producer of aflatoxin and an opportunistic pathogen for a wide range of hosts. Understanding genotypic and phenotypic variations within strains of A. flavus is important for controlling disease and reducing aflatoxin contamination. A. flavus is multinucleate and predomi...

  5. Studies on Aspergillus Flavus Link. Isolated From Maize in Iran

    OpenAIRE

    Houshyar-Fard Mahmoud; Rouhani Hamid; Falahati-Rastegar Mahrokh; Mahdikhani-Moghaddam Esmat; Malekzadeh-Shafaroudi Saeed; Probst Claudia

    2014-01-01

    The Aspergillus flavus population structure from maize kernels was examined. During 2011, samples were collected from two main grain maize production areas in Iran (Fars and Ardebil provinces), shortly before harvest. One-hundred nine A. flavus isolates were recovered on Dichloran Rose Bengal Chloramphenicole (DRBC) agar and Aspergillus flavus/parasiticus medium (AFPA) and grouped into morphotypes and Vegetative Compatibility Groups (VCGs) based on morphological (e.g. sclerotia production), p...

  6. Scleral buckle infection with aspergillus flavus

    Directory of Open Access Journals (Sweden)

    Bouhaimed Manal

    2008-01-01

    Full Text Available Purpose: To present a case of scleral buckle infection with Aspergillus flavus in a tertiary eye center in Saudi Arabia. Methods: A retrospective case report of a 28-year-old Saudi male who presented with a six-month history of conjunctival injection and discharge from the left eye which had undergone uncomplicated conventional retinal detachment surgery, at the King Khaled Eye Specialist Hospital in Riyadh, Saudi Arabia, in the form of cryopexy, subretinal fluid drainage and scleral buckle (grooved segmental sponge and circumferential band with sleeve for a macula on retinal detachment four years earlier. A diagnosis of infected extruded scleral buckle was made and the buckle was removed. Results: The infected scleral buckle was removed under local anesthesia with administration of sub-conjunctival irrigation of 50 mg solution of Vancomycin, and sub-conjunctival injection of 25mg of Vancomycin. Post operative microbiological studies revealed infection with silver staining of moderate Aspergillus flavus hyphae. Visual acuity of the left eye improved from 20/200 before surgery to 20/60 in the two years follow-up visit. Conclusion: This case report indicates the importance of considering infection with multiple organisms - including fungal ones - in cases of scleral buckle infections in our population.

  7. Nutrient Environments Influence Competition among Aspergillus flavus Genotypes

    OpenAIRE

    Mehl, Hillary L.; Cotty, Peter J.

    2013-01-01

    The population dynamics of Aspergillus flavus, shaped in part by intraspecific competition, influence the likelihood and severity of crop aflatoxin contamination. Competition for nutrients may be one factor modulating intraspecific interactions, but the influences of specific types and concentrations of nutrients on competition between genotypes of A. flavus have not been investigated. Competition between paired A. flavus isolates on agar media was affected by varying concentrations of carbon...

  8. Nutrient environment influences competition among Aspergillus flavus genotypes

    Science.gov (United States)

    Structures of Aspergillus flavus populations, shaped by intraspecific competition, influence the incidences and severities of crop aflatoxin contamination. Competition for nutrients may be one factor modulating intraspecific interactions, but influences of specific types and concentrations of nutrie...

  9. The maize rachis affects Aspergillus flavus movement during ear development

    Science.gov (United States)

    Aspergillus flavus expressing green fluorescent protein (GFP) was used to follow infection in ears of maize hybrids resistant and susceptible to the fungus. Developing ears were needle-inoculated with GFP-transformed A. flavus 20 days after silk emergence, and GFP fluorescence in the pith was evalu...

  10. Experimental study of Aspergillus flavus fungus from uranium mines

    International Nuclear Information System (INIS)

    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.)

  11. Cryptic Sexuality in Aspergillus parasiticus and A. flavus

    Science.gov (United States)

    Ascomycetous fungi of the genus Aspergillus comprise a wide variety of species of biotechnological importance (e.g. A. sojae, A. oryzae, A. niger) as well as pathogens and toxin producers (e.g. A. flavus, A. parasiticus, A. fumigatus, A. nidulans). With the exception of A. nidulans, which is a homot...

  12. CONTROL OF AFLATOXIGENIC Aspergillus flavus IN PEANUTS USING NONAFLATOXIGENIC A. flavus, A. niger and Trichoderma harzianum

    Directory of Open Access Journals (Sweden)

    OKKY SETYAWATI DHARMAPUTRA

    2003-01-01

    Full Text Available The effects of nontoxigenic Aspergillus flavus, A. niger and Trichoderma harzianum inoculated into planting media on toxigenic A. flavus infection and its aflatoxin production in peanut kernels at harvest were investigated together with (1 the moisture content of planting media before peanut planting, at the time of inflorescence, and at harvest, (2 the population of aflatoxigenic and nonaflatoxigenic A. flavus, A. niger and T. harzianum in peanut planting media before peanut planting, at the time of inflorescence, and at harvest, (3 the moisture content of peanut kernels at harvest, and (4 toxigenic A. flavus invasion in peanut plant parts (r oots, stems, petioles, leaves and flowers at the time of inflorescence. The fungal isolates were inoculated into planting media at the same time with the planting of peanut seeds. Peanut plants were grown under glasshouse conditions. Treated planting media were inoculated with the combined use of (1 toxigenic and nontoxigenic A. flavus, (2 toxigenic A. flavus and A. niger, and (3 toxigenic A. flavus and T. harzianum. Planting media inoculated only with each fungal isolat e and uninoculated planting media were used as controls. Two watering treatments of peanut plants were carried out, i.e. watering un til harvest and not watering for 15 days before harvest. The populations of the fungal isolates in the planting media and peanut kernels were determined using dilution method followed by pour plate method; the percentages of toxigenic A. flavus and test fungal colonizations in peanut plant parts were de termined using plating method; the moisture content of planting media and peanut kernels were determined using oven method; the aflatoxin content of peanut kernels was determined using Thin Layer Chromatography method. The results indicated that at the time of harvest the decr ease in moisture contents of planting media not watered for 15 days before harvest was higher than those watered until harvest. The

  13. Primary cutaneous aspergillosis due to Aspergillus flavus: a case report

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qiang-qiang; LI Li; ZHU Min; ZHANG Chao-ying; WANG Jia-jun

    2005-01-01

    @@ Infections caused by opportunistic organisms which have been known as etiologic agents of disease become more and more frequent.Aspergillus spp. is one of the agents. Fungi of aspergillus genus are widely distributed in nature, particularly in the soil and in the decomposed vegetation. They are frequent opportunist pathogens in immunocompromised patients. The most frequent causative organisms that cause cutaneous aspergillosis are A.fumigatus and A.flavus.1-3 In this report, we present a case of primary cutaneous aspergillosis manifested by ulceration of the shank due to A. flavus. The patient had no deficiency of immunological status and severe disease associated with fungal infection. Excellent response was shown to anti-fungal therapy.

  14. Lipids in Aspergillus flavus-maize interaction

    Directory of Open Access Journals (Sweden)

    Massimo eReverberi

    2014-02-01

    Full Text Available In sSome filamentous fungi, the pathways related to the oxidative stress and oxylipins production are involved both in the process of host-recognition of the host that and in the pathogenic phase. In fact, recent studies have shown that the production of oxylipins in filamentous fungi, yeasts and chromists is also related to the development of the organism itself and to mechanisms of communication with the host at the cellular level. The oxylipins, also involved produced in by the host during defense reactions, are able to induce sporulation and to modulate regulate the biosynthesis of mycotoxins in numerous several pathogenic fungi, apparently replacing the endogenous ones. In A. flavus, the oxylipins play a crucial role as signals for the regulation regulatingof the biosynthesis of aflatoxins, the conidiogenesis and the formation of sclerotia.To investigate the involvement of the an oxylipins based cross-talk into Z. mays and A. flavus interaction, we analyzed the oxylipins profile of the wild type strain and of three mutants of A. flavus that are deleted at the Aflox1 gene level also during maize kernel invasion; Aflox1 encodes for a manganese lipoxygenase.A lipidomic approach has been addressed through the use of LC-ToF-MS, followed by a statistical analysis of the principal components (PCA. The results showed the existence of a difference between the oxylipins profile generated by the WT and the mutants onto challenged maize. In relation to this, aflatoxin synthesis which is largely hampered in vitro, is intriguingly restored. These results highlight the important role of maize oxylipin in driving secondary metabolism in A. flavus.

  15. The complete mitochondrial genome sequence of Aspergillus flavus.

    Science.gov (United States)

    Yan, Zhengsong; Chen, Dan; Shen, Yiping; Ye, Baodong

    2016-07-01

    Aspergillus flavus is a haploid filamentous fungus that is common in the environment and has been implicated in human infections. The complete mitochondrial genome of A. flavus has been determined by high-throughput sequencing technology in this work. Our study revealed that the mitochondrial genome of A. flavus is 31,602 bp long, with an A + T content of 74.83%, which consists of a usual set of mitochondrial proteins and RNA genes, including large and small ribosomal RNAs, 15 proteins, and 20 tRNA genes and contains two introns. Notably, it also contains two hypothetical proteins without obvious homology to any known proteins. All structural genes are located on one strand and are apparently transcribed in one direction. Codon usage analysis indicated that all protein coding genes employ the standard fungal mitochondrial start and stop codons; and the nucleotide bias toward AT was also reflected in the codon usage. The complete mitochondrial genomes of A. flavus would be useful for future investigation of the genetic, evolution, and clinical identification of Aspergillus species. PMID:25922962

  16. Transcriptomic profiling of Aspergillus flavus in response to 5-azacytidine.

    Science.gov (United States)

    Lin, Jian-Qing; Zhao, Xi-Xi; Zhi, Qing-Qing; Zhao, Ming; He, Zhu-Mei

    2013-07-01

    Aspergillus flavus is a common saprophyte and opportunistic pathogen producing aflatoxin (AF) and many other secondary metabolites. 5-Azacytidine (5-AC), a derivative of the nucleoside cytidine, is widely used for studies in epigenetics and cancer biology as an inactivator of DNA methyltransferase and is also used for studying secondary metabolism in fungi. Our previous studies showed that 5-AC affects development and inhibits AF production in A. flavus, and that A. flavus lacks DNA methylation. In this study, an RNA-Seq approach was applied to explore the mechanism of 5-AC's effect on A. flavus. We identified 240 significantly differentially expressed (Q-value<0.05) genes after 5-AC treatment, including two backbone genes respectively in secondary metabolite clusters #27 and #35. These two clusters are involved in development or survival of sclerotia. GO functional enrichment analysis showed that these significantly differentially expressed genes were mainly involved in catalytic activity and proteolytic functions. The expressed transcripts of most genes in the AF biosynthetic gene cluster in A. flavus showed no significant changes after treatment with 5-AC and were expressed at low levels, and the transcription regulator genes aflR and aflS in this cluster did not show differential expression relative to the sample without 5-AC treatment. We found that the veA gene, which encodes protein bridges VelB and LaeA, decreased profoundly the expressed transcripts, and brlA, which encodes an early regulator of development, increased its transcripts in A. flavus after 5-AC treatment. Our data support a model whereby 5-AC affects development through increasing the expression of brlA by depressing the expression of veA and AF production through suppressing veA expression and dysregulating carboxypeptidase activity, which then prevents the aflatoxisomes (vesicles) from performing their normal function in AF formation. Furthermore, the suppressed veA expression weakens or

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

    International Nuclear Information System (INIS)

    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

  18. Aspergillus flavus and aflatoxin B1 in flour production.

    Science.gov (United States)

    Halt, M

    1994-10-01

    This paper discusses the results of investigations of contamination with aflatoxin-producing fungi and aflatoxin B1 affecting 545 samples of wheat grains, 475 samples of intermediate products of wheat grain being milled to flour (like middlings) and 238 samples of flour. A significant contamination with moulds was detected in analyzed samples. Although Aspergillus (34.87%) and Penicillium (32.37%) dominated, other types were also present, e.g., Cladosporium, Fusarium, Mucor, Alternaria, Rhizopus, Absidia and Trichoderma (listed in order of frequency). The presence of Aspergillus flavus, the known aflatoxin producer, was detected in 9.94% of analyzed samples. Isolates of A. Flavus were capable of producing aflatoxin B1 under favourable conditions. Aflatoxin B1 was found in 76.8% of samples contaminated with A. flavus. The highest contamination with aflatoxin B1 was detected in wheat grain samples (mean value of 16.3 micrograms/kg) and in intermediate products of wheat grain being milled to flour (mean value of 11.13 micrograms/kg). Contamination was lower in flour samples (mean value of 4.13 micrograms/kg). With regard to proposed standards given by the FAO and WHO, under which the content of aflatoxin should not exceed 30 micrograms/kg in food products, only two of 96 samples did not meet these criteria. PMID:7859854

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

    International Nuclear Information System (INIS)

    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 B1 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.

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

    Science.gov (United States)

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

    2011-05-01

    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.

  1. The population genomics of mycotoxin diversity in Aspergillus flavus and Aspergillus parasiticus

    Science.gov (United States)

    Mycotoxins, and especially the aflatoxins, are an enormous problem in agriculture, with aflatoxin B1 being the most carcinogenic known natural compound. The worldwide costs associated with aflatoxin monitoring and crop losses are in the hundreds of millions of dollars. Aspergillus flavus and A. par...

  2. How peroxisomes affect aflatoxin biosynthesis in Aspergillus flavus.

    Directory of Open Access Journals (Sweden)

    Massimo Reverberi

    Full Text Available In filamentous fungi, peroxisomes are crucial for the primary metabolism and play a pivotal role in the formation of some secondary metabolites. Further, peroxisomes are important site for fatty acids β-oxidation, the formation of reactive oxygen species and for their scavenging through a complex of antioxidant activities. Oxidative stress is involved in different metabolic events in all organisms and it occurs during oxidative processes within the cell, including peroxisomal β-oxidation of fatty acids. In Aspergillus flavus, an unbalance towards an hyper-oxidant status into the cell is a prerequisite for the onset of aflatoxin biosynthesis. In our preliminary results, the use of bezafibrate, inducer of both peroxisomal β-oxidation and peroxisome proliferation in mammals, significantly enhanced the expression of pex11 and foxA and stimulated aflatoxin synthesis in A. flavus. This suggests the existence of a correlation among peroxisome proliferation, fatty acids β-oxidation and aflatoxin biosynthesis. To investigate this correlation, A. flavus was transformed with a vector containing P33, a gene from Cymbidium ringspot virus able to induce peroxisome proliferation, under the control of the promoter of the Cu,Zn-sod gene of A. flavus. This transcriptional control closely relates the onset of the antioxidant response to ROS increase, with the proliferation of peroxisomes in A. flavus. The AfP33 transformant strain show an up-regulation of lipid metabolism and an higher content of both intracellular ROS and some oxylipins. The combined presence of a higher amount of substrates (fatty acids-derived, an hyper-oxidant cell environment and of hormone-like signals (oxylipins enhances the synthesis of aflatoxins in the AfP33 strain. The results obtained demonstrated a close link between peroxisome metabolism and aflatoxin synthesis.

  3. AMINO ACID SUPPLEMENTATION REVEALS DIFFERENTIAL REGULATION OF AFLATOXIN BIOSYNTHESIS IN ASPERGILLUS FLAVUS NRRL 3357 AND ASPERGILLUS PARASITICUS SRRC 143

    Science.gov (United States)

    Aflatoxins are toxic and carcinogenic secondary metabolites produced by the fungi Aspergillus flavus and A. parasiticus. In order to better understand the molecular mechanisms that regulate aflatoxin production, the biosynthesis of the toxin in A. flavus and A. parasiticus grown in yeast extract su...

  4. Evaluation of intraspecific competition (Aspergillus flavus Link) and aflatoxin formation in suspended disc culture and preharvest maize

    Science.gov (United States)

    The abilities of non-aflatoxin producing strains of Aspergillus flavus NRRL 32354; 18543; 21882; 21368 as well as domesticated koji strains Aspergillus oryzae (syn. A. flavus var. oryzae) NRRL 451; 1911; 5592; 6271; 30038 to interfere with aflatoxin formation by A. flavus NRRL 3357; 32355 were exami...

  5. Characterization of an Aspergillus flavus alkaline protease and its role in the infection of maize kernels

    Science.gov (United States)

    A 33 kDa protein present in Aspergillus flavus infected maize embryo tissue was identified as a fungal alkaline protease (ALP). This protein became one of the major extracellular proteins of A. flavus in potato dextrose broth medium cultural filtrate after 3 days, but was expressed at low levels or ...

  6. Volatile profiles of toxigenic and non-toxigenic Aspergillus flavus using SPME for solid phase extraction

    Science.gov (United States)

    Toxigenic and atoxigenic strains of Aspergillus flavus were grown on potato dextrose agar (PDA) and wetted sterile, cracked corn for 21 and 14 days, respectively. Volatile compounds produced by A. flavus, as well as those present in the PDA controls and sterile cracked corn, were collected using sol...

  7. Aspergillus flavus Blast2GO gene ontology database: elevated growth temperature alters amino acid metabolism

    Science.gov (United States)

    The availability of a representative gene ontology (GO) database is a prerequisite for a successful functional genomics study. Using online Blast2GO resources we constructed a GO database of Aspergillus flavus. Of the predicted total 13,485 A. flavus genes 8,987 were annotated with GO terms. The mea...

  8. Aspergillus flavus Genomic Data Mining Provides Clues for Its Use in Producing Biobased Products

    Science.gov (United States)

    Aspergillus flavus is notorious for its ability to produce aflatoxins. It is also an opportunistic pathogen that infects plants, animals and human beings. The ability to survive in the natural environment, living on plant tissues (leaves or stalks), live or dead insects make A. flavus a ubiquitous...

  9. 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.

  10. Sexual reproduction influences aflatoxin chemotype diversity in worldwide populations of Aspergillus flavus and A. parasiticus

    Science.gov (United States)

    Aflatoxins are toxic polyketides produced by several Aspergillus species that contaminate food crops worldwide. Aspergillus flavus and A. parasiticus are the most common agents of aflatoxin contamination of oil-rich crops. The genes involved in aflatoxin biosynthesis are clustered and convert acetat...

  11. Aspergillus Flavus Endocarditis of the Native Mitral Valve in a Bone Marrow Transplant Patient

    OpenAIRE

    Demir, Tolga; Ergenoglu, Mehmet Umit; Ekinci, Abdurrahman; Tanrikulu, Nursen; Sahin, Mazlum; Demirsoy, Ergun

    2015-01-01

    Patient: Male, 36 Final Diagnosis: Aspergillus flavus endocarditis Symptoms: Malaise • fatigue and dyspnea Medication: — Clinical Procedure: Mitral vale replacemnet Specialty: Cardiology Objective: Rare disease Background: Infective endocarditis due to Aspergillus species is an uncommon infection with a high mortality rate. It mostly occurs after the implantation of prosthetic heart valves. Parenteral nutrition, immunosuppression, broad-spectrum antibiotic regimens, and illegal intravenous dr...

  12. Effect of irradiation on aflatoxin production by Aspergillus flavus

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Hitoshi; Jintana Bunnak; Guzman, Z.M. de; Ishigaki, Isao (Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment)

    1991-10-01

    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{sub 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{sub 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{sub 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).

  13. Effect of irradiation on aflatoxin production by Aspergillus flavus

    International Nuclear Information System (INIS)

    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 D10 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 B1 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 B1 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)

  14. Aspergillus flavus-Induced Brain Abscess in an Immunocompetent Child

    Science.gov (United States)

    Al-Maskari, Nawal; Hussain, Ibrahim; Jumaa, Suleiman; Al-Shail, Essam A.

    2016-01-01

    Intracranial aspergillosis is an extremely rare manifestation of invasive aspergillosis in immunocompetent children and is associated with high morbidity and mortality. We report a 12-year-old immunocompetent male child who was referred to the King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia, in May 2010 after a sudden-onset headache and loss of consciousness. Brain imaging revealed a large right space-occupying occipital lesion and the patient underwent a craniotomy and resection. Histopathology of the lesion revealed necrotising granulomatous fungal encephalitis with many hyphae engulfed by multinucleated giant histiocytes. Two days later, a computed tomography scan showed debulking of the fungal mass and the patient was discharged on oral voriconazole. However, imaging at a six-week follow-up showed progression of the abnormality. A residual or persistent fungal brain lesion was suspected. Further neurosurgical resection of the lesion was performed and cultures showed growth of Aspergillus flavus. The patient was treated successfully with antifungal therapy over the following two years. PMID:27226920

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

    DEFF Research Database (Denmark)

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

    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...... with indications to specific genetic changes. Several new metabolites and changes in biosynthetic routes have been found in A. oryzae, indicating subtle changes in the genomic heritage from A. flavus....

  16. Inactivation of Aspergillus flavus in drinking water after treatment with UV irradiation followed by chlorination

    Energy Technology Data Exchange (ETDEWEB)

    Al-Gabr, Hamid Mohammad [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); State Key Laboratory of Environmental Sciences, and Key Laboratory of Ministry of Education for Coast and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005 (China); Zheng, Tianling [State Key Laboratory of Environmental Sciences, and Key Laboratory of Ministry of Education for Coast and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005 (China); Yu, Xin, E-mail: xyu@iue.ac.cn [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China)

    2013-10-01

    The disinfection process for inactivating microorganisms at drinking water treatment plants is aimed for safety of drinking water for humans from a microorganism, such as bacteria, viruses, algae, fungi by using chlorination, ozonation, UV irradiation, etc. In the present study, a combination of two disinfectants, UV irradiation followed by chlorination, was evaluated for inactivating Aspergillus flavus under low contact time and low dosage of UV irradiation. The results indicated an inverse correlation between the inactivation of A. flavus by using UV irradiation only or chlorination alone. By using UV radiation, the 2 log{sub 10} control of A. flavus was achieved after 30 s of irradiation, while chlorination was observed to be more effective than UV, where the 2 log was achieved at chlorine concentration of 0.5, 1, 2 and 3 mg/l, in contact time of 60, 5, 1 and 1 min, respectively. However, combined use (UV irradiation followed by chlorination) was more effective than using either UV or chlorination alone; 5 s UV irradiation followed by chlorination produced 4 log{sub 10} reduction of A. flavus at chlorine concentrations of 2 and 3 mg/l under a contact time of 15 min. The results indicated that efficiency of UV irradiation improves when followed by chlorination at low concentrations. - Highlights: • As a disinfectant, chlorine is more effective than UV in inactivating Aspergillus flavus. • As a combined method, UV irradiation followed by chlorination shows high efficiency. • UV irradiation can improve effectiveness of chlorination in reducing Aspergillus flavus.

  17. Inactivation of Aspergillus flavus in drinking water after treatment with UV irradiation followed by chlorination

    International Nuclear Information System (INIS)

    The disinfection process for inactivating microorganisms at drinking water treatment plants is aimed for safety of drinking water for humans from a microorganism, such as bacteria, viruses, algae, fungi by using chlorination, ozonation, UV irradiation, etc. In the present study, a combination of two disinfectants, UV irradiation followed by chlorination, was evaluated for inactivating Aspergillus flavus under low contact time and low dosage of UV irradiation. The results indicated an inverse correlation between the inactivation of A. flavus by using UV irradiation only or chlorination alone. By using UV radiation, the 2 log10 control of A. flavus was achieved after 30 s of irradiation, while chlorination was observed to be more effective than UV, where the 2 log was achieved at chlorine concentration of 0.5, 1, 2 and 3 mg/l, in contact time of 60, 5, 1 and 1 min, respectively. However, combined use (UV irradiation followed by chlorination) was more effective than using either UV or chlorination alone; 5 s UV irradiation followed by chlorination produced 4 log10 reduction of A. flavus at chlorine concentrations of 2 and 3 mg/l under a contact time of 15 min. The results indicated that efficiency of UV irradiation improves when followed by chlorination at low concentrations. - Highlights: • As a disinfectant, chlorine is more effective than UV in inactivating Aspergillus flavus. • As a combined method, UV irradiation followed by chlorination shows high efficiency. • UV irradiation can improve effectiveness of chlorination in reducing Aspergillus flavus

  18. The DmtA methyltransferase contributes to Aspergillus flavus conidiation, sclerotial production, aflatoxin biosynthesis and virulence

    OpenAIRE

    Kunlong Yang; Linlin Liang; Fanlei Ran; Yinghang Liu; Zhenguo Li; Huahui Lan; Peili Gao; Zhenhong Zhuang; Feng Zhang; Xinyi Nie; Shimuye Kalayu Yirga; Shihua Wang

    2016-01-01

    DNA methylation is essential for epigenetic regulation of gene transcription and development in many animals, plants and fungi. We investigated whether DNA methylation plays a role in the development and secondary metabolism of Aspergillus flavus, identified the DmtA methyltransferase from A. flavus, and produced a dmtA knock-out mutant by replacing the dmtA coding sequence with the pyrG selectable marker. The A. flavus dmtA null mutant lines produced white fluffy mycelium in liquid medium, a...

  19. Bisulfite sequencing reveals that Aspergillus flavus holds a hollow in DNA methylation

    DEFF Research Database (Denmark)

    Liu, Si-Yang; Lin, Jian-Qing; Wu, Hong-Long;

    2012-01-01

    Aspergillus flavus first gained scientific attention for its production of aflatoxin. The underlying regulation of aflatoxin biosynthesis has been serving as a theoretical model for biosynthesis of other microbial secondary metabolites. Nevertheless, for several decades, the DNA methylation status......, one of the important epigenomic modifications involved in gene regulation, in A. flavus remains to be controversial. Here, we applied bisulfite sequencing in conjunction with a biological replicate strategy to investigate the DNA methylation profiling of A. flavus genome. Both the bisulfite sequencing...... detection in species with low DNA methylation may serve as a reference for later scientific investigations in other hypomethylated species....

  20. Aflatoxin production by Aspergillus Flavus on irradiated and non-irradiated stored egyptian bread

    International Nuclear Information System (INIS)

    Aflatoxins production by Aspergillus Flavus isolate on several types of egyptian bread samples through a period of 45 days at different temperatures reveled that there was detectable fungal growth but no aflatoxins were produced at 5±1 degree or 37 degree. At 25 degree or 30 degree aflatoxin were produced after 5-6 days on the different bread types. Gamma irradiation of kaiser bread, previously inoculated with Aspergillus Flavus, reduced the amount of aflatoxins produced on subsequent storage for 8 weeks at 26±1 degree. The 5 KGy dose eliminated fungal growth and aflatoxin production. 4 tab

  1. The effect of 2-phenylethanol treatment on Aspergillus flavus transcriptome

    Science.gov (United States)

    Pichia anomalais, which produces the antimicrobial volatile 2-phenylethanol (2-PE), is effective in reducing A. flavus growth and aflatoxin production. We treated A. flavus NRRL3357 with 2-PE and analyzed changes in the transcriptomic profiles at different stages of fungal growth. RNA-Seq reads from...

  2. Evaluation of antifungal activity of essential oils against potentially mycotoxigenic Aspergillus flavus and Aspergillus parasiticus

    Directory of Open Access Journals (Sweden)

    Fernanda C. da Silva

    2012-10-01

    Full Text Available The antifungal activity of essential oils of fennel (Foeniculum vulgare Mill., Apiaceae, ginger (Zingiber officinale Roscoe, Zingiberaceae, mint (Mentha piperita L., Lamiaceae and thyme (Thymus vulgaris L., Lamiaceae was evaluated against mycotoxin producers Aspergillus flavus and A. parasiticus. High Resolution Gas Chromatography was applied to analyze chemical constituents of essential oils. The effect of different concentrations of essential oils was determined by solid medium diffusion assay. Mycelial growth and sporulation were determined for each essential oil at the concentrations established by solid medium diffusion assay. At the fifth, seventh and ninth days the mycelial diameter (Ø mm and spore production were also determined. FUN-1 staining was performed to assess cell viability after broth macrodilution assay. Trans-anethole, zingiberene, menthol and thymol are the major component of essential oils of fennel, ginger, mint and thyme, respectively. The effective concentrations for fennel, ginger, mint and thyme were 50, 80, 50 and 50% (oil/DMSO; v/v, respectively. The four essential oils analysed in this study showed antifungal effect. Additionally, FUN-1 staining showed to be a suitable method to evaluate cell viability of potential mycotoxigenic fungi A. flavus and A. parasiticus after treatment with essential oils.

  3. Local isolate of Saccharomyces cerevisiae as biocompetitive agent of Aspergillus flavus

    Directory of Open Access Journals (Sweden)

    Eni Kusumaningtyas

    2006-12-01

    Full Text Available Aspergillus flavus is a toxigenic fungus that contaminates feed and influences the animal health. Saccharomyces cerevisiae can be used as a biocompetitive agent to control the contamination. The ability of local isolate of S. cerevisiae as a biocompetitive agent for A. flavus was evaluated. A. flavus (30ml was swept on Sabouraud dextrose agar (SDA, while S. cerevisiae was swept on its left and right. Plates were incubated at 28oC for nine days. Lytic activity of S. cerevisiae was detected by pouring its suspension on the centre of the cross streaks of A. flavus. Plates were incubated at 28oC for five days. Growth inhibition of A. flavus by S. cerevisiae was determined by mixing the two fungi on Potato dextrose broth and incubated at 28oC for 24 hours. Total colony of A. flavus were then observed at incubation time of 2, 4, 6 and 24 hours by pour plates method on the SDA plates and incubated on 28oC for two days. Growth of hyphae of A. flavus sweep were inhibited with the swept of S. cerevisiae. The width of A. flavus colony treated with S. cerevisiae is narrower (3,02 cm than that of control ( 4,60 cm. The growth of A. flavus was also inhibited on the centre of cross streak where the S. cerevisiae poured. S. cerevisiae gradually reduced the colony number of A. flavus in the mixed culture of broth fungi ie. 14 x 103 CFU/ml while colony number of control is 80 x 103 CFU/ml. Results showed that S. cerevisiae could be used as biocompetitive agent of A. flavus.

  4. Bisulfite sequencing reveals that Aspergillus flavus holds a hollow in DNA methylation.

    Directory of Open Access Journals (Sweden)

    Si-Yang Liu

    Full Text Available Aspergillus flavus first gained scientific attention for its production of aflatoxin. The underlying regulation of aflatoxin biosynthesis has been serving as a theoretical model for biosynthesis of other microbial secondary metabolites. Nevertheless, for several decades, the DNA methylation status, one of the important epigenomic modifications involved in gene regulation, in A. flavus remains to be controversial. Here, we applied bisulfite sequencing in conjunction with a biological replicate strategy to investigate the DNA methylation profiling of A. flavus genome. Both the bisulfite sequencing data and the methylome comparisons with other fungi confirm that the DNA methylation level of this fungus is negligible. Further investigation into the DNA methyltransferase of Aspergillus uncovers its close relationship with RID-like enzymes as well as its divergence with the methyltransferase of species with validated DNA methylation. The lack of repeat contents of the A. flavus' genome and the high RIP-index of the small amount of remanent repeat potentially support our speculation that DNA methylation may be absent in A. flavus or that it may possess de novo DNA methylation which occurs very transiently during the obscure sexual stage of this fungal species. This work contributes to our understanding on the DNA methylation status of A. flavus, as well as reinforces our views on the DNA methylation in fungal species. In addition, our strategy of applying bisulfite sequencing to DNA methylation detection in species with low DNA methylation may serve as a reference for later scientific investigations in other hypomethylated species.

  5. Application of biotechnology towards the enhancement of maize resistance to aflatoxin contamination by Aspergillus flavus

    Science.gov (United States)

    Contamination of maize with aflatoxins by the fungi Aspergillus flavus and A. parasiticus poses serious health hazards to humans and animals worldwide. This important fact and the regulations instituted in many countries to control the occurrence of aflatoxins in foods and feed have stimulated rese...

  6. Influence of Gene Expression on Variable Aflatoxin Production by Different Strains of Aspergillus flavus

    Science.gov (United States)

    Aspergillus flavus is a globally distributed fungus. It causes disease in human and crop plants due to the production of numerous conidia dispersed by air movement and possibly by insects. The fungus is an economically important food contaminant because it produces the most potent natural carcinogen...

  7. Comparative chemistry of Aspergillus oryzae (RIB40) and A. flavus (NRRL 3357)

    DEFF Research Database (Denmark)

    Rank, Christian; Klejnstrup, Marie Louise; Petersen, Lene Maj;

    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...

  8. Genome wide association mapping of Aspergillus flavus and aflatoxin accumulation resistance in maize

    Science.gov (United States)

    Contamination of maize with aflatoxin, produced by the fungus Aspergillus flavus, has severe health and economic consequences. Efforts to reduce aflatoxin accumulation in maize have focused on identifying and selecting germplasm with natural host resistance factors, and several maize lines with sign...

  9. Efficacy of water dispersible formulations of biocontrol strains of Aspergillus flavus for aflatoxin management in corn

    Science.gov (United States)

    Field experiments were conducted in 2011 and 2012 to evaluate the efficacy of water dispersible granule (WDG) formulations of biocontrol strains of Aspergillus flavus in controlling aflatoxin contamination of corn. In 2011, when aflatoxin was present at very high levels, no WDG treatment provided s...

  10. Intraspecific competition during infection by Aspergillus flavus is influenced by plant host species

    Science.gov (United States)

    Communities of Aspergillus flavus are composed of diverse genotypes that collectively influence incidence and severity of crop aflatoxin contamination. Isolates vary in competitive ability on maize, but empirical data on the extent to which host-specific influences determine outcomes of competition ...

  11. Aspergillus flavus whole genome and EST sequence releases and construction of homologous gene search blast server

    Science.gov (United States)

    Aflatoxins are toxic and carcinogenic secondary metabolites. These compounds, produced by Aspergillus flavus and A. parasiticus, contaminate pre-harvest agricultural crops in the field and post-harvest grains during storage. In order to reduce and eliminate aflatoxin contamination of food and feed...

  12. Aflatoxigenesis induced in Aspergillus flavus by oxidative stress and reduction by phenolic antioxidants from tree nuts

    Science.gov (United States)

    Almonds, pistachios, and walnuts grown in California have an aggregate value of over $3.3 billion, with a large proportion of the crop being exported. However, these tree nuts can be subject to contamination by aflatoxins, metabolites produced primarily by Aspergillus flavus and parasiticus, and im...

  13. A maize lectin-like protein with antifungal activity against Aspergillus flavus

    Science.gov (United States)

    The filamentous fungus, Aspergillus flavus, causes an ear rot on maize and produces a mycotoxin, aflatoxin, in colonized maize kernels. Aflatoxins are carcinogenic to humans and animals upon ingestion. The presence of aflatoxins in food and feed is strictly regulated by several governmental agenci...

  14. Identification of novel metabolites from Aspergillus flavus by high resolution and multiple stage mass spectrometry

    Science.gov (United States)

    Aspergillus flavus contains more than 55 gene clusters which are predicted to encode proteins involved in secondary metabolite production. One of these, cluster 27, contains a polyketide synthase (pks27) gene which encodes a protein that is highly homologous to the aflatoxin cluster PKS. Comparative...

  15. Functional Genomic Analysis of Aspergillus flavus Interacting with Resistant and Susceptible Peanut

    Directory of Open Access Journals (Sweden)

    Houmiao Wang

    2016-02-01

    Full Text Available In the Aspergillus flavus (A. flavus–peanut pathosystem, development and metabolism of the fungus directly influence aflatoxin contamination. To comprehensively understand the molecular mechanism of A. flavus interaction with peanut, RNA-seq was used for global transcriptome profiling of A. flavus during interaction with resistant and susceptible peanut genotypes. In total, 67.46 Gb of high-quality bases were generated for A. flavus-resistant (af_R and -susceptible peanut (af_S at one (T1, three (T2 and seven (T3 days post-inoculation. The uniquely mapped reads to A. flavus reference genome in the libraries of af_R and af_S at T2 and T3 were subjected to further analysis, with more than 72% of all obtained genes expressed in the eight libraries. Comparison of expression levels both af_R vs. af_S and T2 vs. T3 uncovered 1926 differentially expressed genes (DEGs. DEGs associated with mycelial growth, conidial development and aflatoxin biosynthesis were up-regulated in af_S compared with af_R, implying that A. flavus mycelia more easily penetrate and produce much more aflatoxin in susceptible than in resistant peanut. Our results serve as a foundation for understanding the molecular mechanisms of aflatoxin production differences between A. flavus-R and -S peanut, and offer new clues to manage aflatoxin contamination in crops.

  16. Efficacy of corn and rice seed-borne mycoflora in controlling aflatoxigenic Aspergillus flavus

    Directory of Open Access Journals (Sweden)

    Adel K. Madbouly

    2014-02-01

    Full Text Available Food commodities such as cereals are subjected to spoilage and bio-deterioration during storage by mycotoxigenic fungi such as Aspergillus flavus. Efforts are done to biologically control toxigenic A. flavus and subsequently prevent or at least minimize its aflatoxin production ability, without the need of using synthetic fungicides. Antifungal activity of corn and rice seed-borne mycoflora was tested against aflatoxigenic A. flavus in vitro, using bioassays such as dual culture technique; ability to produce volatile and non-volatile metabolites; ability to inhibit germination and reduce germ tube length of A. flavus conidia; in vivo reduction of aflatoxins level in corn seeds co-inoculated with the pathogen and antagonists. Penicillum crustosum, Aspergillus giganteus, Fusarium verticillioides and Aspergillus fumigatus isolates showed promising antifungal activities and varying efficiencies of reducing aflatoxins level; however, only A. fumigatus isolate was non-aflatoxigenic. It could be concluded that A. fumigatus could be used effectively as a biopreservative to increase shelf life of cereals during storage, but after testing its tendency to produce other mycotoxins or causing human Aspergillosis.

  17. A survey on distribution and toxigenicity of Aspergillus flavus from indoor and outdoor hospital environments.

    Science.gov (United States)

    Sepahvand, Asghar; Shams-Ghahfarokhi, Masoomeh; Allameh, Abdolamir; Jahanshiri, Zahra; Jamali, Mojdeh; Razzaghi-Abyaneh, Mehdi

    2011-11-01

    In the present study, genetic diversity and mycotoxin profiles of Aspergillus flavus isolated from air (indoors and outdoors), levels (surfaces), and soils of five hospitals in Southwest Iran were examined. From a total of 146 Aspergillus colonies, 63 isolates were finally identified as A. flavus by a combination of colony morphology, microscopic criteria, and mycotoxin profiles. No Aspergillus parasiticus was isolated from examined samples. Chromatographic analyses of A. flavus isolates cultured on yeast extract-sucrose broth by tip culture method showed that approximately 10% and 45% of the isolates were able to produce aflatoxin B(1) (AFB(1)) and cyclopiazonic acid (CPA), respectively. Around 40% of the isolates produced sclerotia on Czapek-Dox agar. The isolates were classified into four chemotypes based on the ability to produce AF and CPA that majority of them (55.5%) belonged to chemotype IV comprising non-mycotoxigenic isolates. Random amplified polymorphic DNA (RAPD) profiles generated by a combination of four selected primers were used to assess genetic relatedness of 16 selected toxigenic and non-toxigenic isolates. The resulting dendrogram demonstrated the formation of two separate clusters for the A. flavus comprised both mycotoxigenic and non-toxigenic isolates in a random distribution. The obtained results in this study showed that RAPD profiling is a promising and efficient tool to determine intra-specific genetic variation among A. flavus populations from hospital environments. A. flavus isolates, either toxigenic or non-toxigenic, should be considered as potential threats for hospitalized patients due to their obvious role in the etiology of nosocomial aspergillosis. PMID:22083786

  18. Antifungal Metabolites (Monorden, Monocillin IV, and Cerebrosides) from Humicola fuscoatra Traaen NRRL 22980, a Mycoparasite of Aspergillus flavus Sclerotia

    OpenAIRE

    Wicklow, Donald T.; Joshi, Biren K.; Gamble, William R.; Gloer, James B.; Dowd, Patrick F.

    1998-01-01

    The mycoparasite Humicola fuscoatra NRRL 22980 was isolated from a sclerotium of Aspergillus flavus that had been buried in a cornfield near Tifton, Ga. When grown on autoclaved rice, this fungus produced the antifungal metabolites monorden, monocillin IV, and a new monorden analog. Each metabolite produced a clear zone of inhibition surrounding paper assay disks on agar plates seeded with conidia of A. flavus. Monorden was twice as inhibitory to A. flavus mycelium extension (MIC > 28 μg/ml) ...

  19. Aspergillus flavus diversity on crops and in the environment can be exploited to reduce aflatoxin exposure and improve health

    Science.gov (United States)

    Humans and animals are exposed to aflatoxins, toxic carcinogenic fungal metabolites, through consumption of contaminated food and feed. Aspergillus flavus, the primary causal agent of crop aflatoxin contamination, is composed of phenotypically and genotypically diverse vegetative compatibility group...

  20. Genome sequence of Aspergillus flavus NRRL 3357, a strain that causes aflatoxin contamination of food and feed

    Science.gov (United States)

    Aflatoxin contamination of food and livestock feed results in significant annual crop losses internationally. Aspergillus flavus is the major fungus responsible for this loss. Additionally, A. flavus is the second leading cause of aspergillosis in immune compromised human patients. Here we report th...

  1. Antifungal Effects of Thyme, Agastache and Satureja Essential Oils on Aspergillus fumigatus, Aspergillus flavus and Fusarium solani

    Directory of Open Access Journals (Sweden)

    Karim Mardani

    2010-09-01

    Full Text Available Growth inhibition of Aspergillus fumigatus,Aspergillus flavus and Fusarum solani exposed to the essential oils including Thyme, Agastache and Satureja were studied. Disc Diffusion Method was used to evaluate the fungal growth inhibitory effects of the essential oils. Minimal inhibitory concentration (MIC and minimal fungicidal concentration (MFC of the oils were determined and compared with each other. The results showed that all three essential oils examined, had antifungal effects against three fungi species. The MIC data revealed that Thyme oil was the most effective essential oil with the MIC of 62.5 μl ml-1.

  2. Extracellular Xylanolytic and Pectinolytic Hydrolase Production by Aspergillus flavus Isolates Contributes to Crop Invasion.

    Science.gov (United States)

    Mellon, Jay E

    2015-08-01

    Several atoxigenic Aspergillus flavus isolates, including some being used as biocontrol agents, and one toxigenic isolate were surveyed for the ability to produce extracellular xylanolytic and pectinolytic hydrolases. All of the tested isolates displayed good production of endoxylanases when grown on a medium utilizing larch xylan as a sole carbon substrate. Four of the tested isolates produced reasonably high levels of esterase activity, while the atoxigenic biocontrol agent NRRL 21882 isolate esterase level was significantly lower than the others. Atoxigenic A. flavus isolates 19, 22, K49, AF36 (the latter two are biocontrol agents) and toxigenic AF13 produced copious levels of pectinolytic activity when grown on a pectin medium. The pectinolytic activity levels of the atoxigenic A. flavus 17 and NRRL 21882 isolates were significantly lower than the other tested isolates. In addition, A. flavus isolates that displayed high levels of pectinolytic activity in the plate assay produced high levels of endopolygalacturonase (pectinase) P2c, as ascertained by isoelectric focusing electrophoresis. Isolate NRRL 21882 displayed low levels of both pectinase P2c and pectin methyl esterase. A. flavus appears capable of producing these hydrolytic enzymes irrespective of aflatoxin production. This ability of atoxigenic isolates to produce xylanolytic and pectinolytic hydrolases mimics that of toxigenic isolates and, therefore, contributes to the ability of atoxigenic isolates to occupy the same niche as A. flavus toxigenic isolates. PMID:26295409

  3. Extracellular Xylanolytic and Pectinolytic Hydrolase Production by Aspergillus flavus Isolates Contributes to Crop Invasion

    Directory of Open Access Journals (Sweden)

    Jay E. Mellon

    2015-08-01

    Full Text Available Several atoxigenic Aspergillus flavus isolates, including some being used as biocontrol agents, and one toxigenic isolate were surveyed for the ability to produce extracellular xylanolytic and pectinolytic hydrolases. All of the tested isolates displayed good production of endoxylanases when grown on a medium utilizing larch xylan as a sole carbon substrate. Four of the tested isolates produced reasonably high levels of esterase activity, while the atoxigenic biocontrol agent NRRL 21882 isolate esterase level was significantly lower than the others. Atoxigenic A. flavus isolates 19, 22, K49, AF36 (the latter two are biocontrol agents and toxigenic AF13 produced copious levels of pectinolytic activity when grown on a pectin medium. The pectinolytic activity levels of the atoxigenic A. flavus 17 and NRRL 21882 isolates were significantly lower than the other tested isolates. In addition, A. flavus isolates that displayed high levels of pectinolytic activity in the plate assay produced high levels of endopolygalacturonase (pectinase P2c, as ascertained by isoelectric focusing electrophoresis. Isolate NRRL 21882 displayed low levels of both pectinase P2c and pectin methyl esterase. A. flavus appears capable of producing these hydrolytic enzymes irrespective of aflatoxin production. This ability of atoxigenic isolates to produce xylanolytic and pectinolytic hydrolases mimics that of toxigenic isolates and, therefore, contributes to the ability of atoxigenic isolates to occupy the same niche as A. flavus toxigenic isolates.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1992-09-01

    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[sub 1] and G[sub 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).

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

    International Nuclear Information System (INIS)

    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 B1 and G1 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)

  6. Antifungal Activity of Extracts of Rosmarinus officinalis and Thymus vulgaris against Aspergillus flavus and A. ochraceus

    Directory of Open Access Journals (Sweden)

    C. Adelantado

    2010-01-01

    Full Text Available The antifungal activity of ethanolic extracts of Rosmarinus officinalis and Thymus vulgaris were tested against strains of Aspergillus flavus and A. ochraceus, since these two species are common contaminants of cereals and grains and are able to produce and accumulate mycotoxins. The methodology used is based on measuring the inhibition halos produced by discs impregnated with the extracts and establishing their Minimum Inhibitory Concentration (MIC as well as the Minimum Fungicide Concentration (MFC. The results obtained suggest that the assayed extracts affect the proper development of A. flavus and A. ochraceus; leading to a lower MIC (1200 ppm and MFC (2400 ppm for T. vulgaris extract against A. ochraceus than against A. flavus. The results show, that the extracts of Rosmarinus officinalis and Thymus vulgaris used at low concentrations could have significant potential for the biological control of fungi in foodstuffs.

  7. Effect of Plant Essential Oils and Gamma Irradiation on Growth and Aflatoxin Production by Aspergillus Flavus Isolated from Wheat Grains

    International Nuclear Information System (INIS)

    The antifungal potential of essential oils of Thyme (Thymus vulgaris L.) and camphor ( Eucalyptus rostrata L.) was determined on Aspergillus flavus link isolated from wheat grains on Potato dextrose agar (PDA). They inhibited completely mycelia growth of the fungus at 1000 and 2000 ppm, and prevented aflatoxin production at sub lethal dose 500 and 1000 ppm respectively. Gamma radiation was used to control mycelia growth of Aspergillus flavus Link and inhibiting aflatoxin production. A dose level of 3.5 KGy gamma radiation prevented the fungal growth and aflatoxin production by A. flavus link, where a dose of 2.5 K Gy ( the sub lethal dose) prevented about 85% of aflatoxin production

  8. Detection of Aflr Gene and Toxigenicity of Aspergillus flavus Group Isolated from Patients with Fungal Sinusitis

    Directory of Open Access Journals (Sweden)

    P Dehghan

    2008-09-01

    Full Text Available "nBackground: Aspergillus flavus is the second most important Aspergillus species causing human infections particu­larly fun­gal sinusitis. Since little is known about aflatoxin producing ability of clinical isolates, this study was under­taken to de­tect the aflatoxigenic isolates amongst these isolates."nMethods: A total of 23 isolates of A. spp. which were recovered from patients proved to have fungal sinusitis by morpho­logi­cal and histological methods and also 5 additional aflatoxigenic and non-aflatoxigenic reference of A. fla­vus group strains were studied. The isolates were identified morphologically using Czapek Yeast Agar and A. flavus and parasiticus Agar (AFPA. Aflatoxin producing ability of the isolates was confirmed by Thin Layer Chromatogra­phy. Existing of aflR gene the regulatory gene in aflatoxin biosynthesis, were studied in all isolates by PCR method."nResults: All twenty three Aspergillus isolates confirmed as A. flavus group by their macroscopic and microscopic fea­tures. One clinical isolate confirmed as A. oryzae by mycological methods. A. oryzae as well as A. flavus JCM2061 and NCPF2008 and 3 clinical isolates were not able to produce orange pigment on AFPA. From total of 23 iso­lates 4 (17.4% con­firmed to be aflatoxigenic by TLC method. A banding pattern which matched to aflR primers was amplified with approxi­mate size of 800 bp in all 23 clinical A. flavus isolates. A larger banding pattern 1050 bp was revealed in clinical iso­late; strain no.20 as well."nConclusion:  Some clinical sinus isolates are able to produce aflatoxin and all of studied isolates including; A. oryzae, A. parasiti­cus and A. sojae were able to amplify aflR gene under our laboratory conditions.  

  9. Molecular characterization of aflatoxigenic and non-aflatoxigenic Aspergillus flavus isolates collected from corn grains.

    Science.gov (United States)

    Mahmoud, M A; Ali, H M; El-Aziz, A R M; Al-Othman, M R; Al-Wadai, A S

    2014-01-01

    Twelve species from six fungal genera were found to be associated with corn (Zea mays L.) grain samples collected from three main regions of Saudi Arabia. The average frequencies of the most common genera were Aspergillus (11.4%), Fusarium (9.5%), Penicillium (5.1%), and Alternaria (5.8%). Fifteen isolates of Aspergillus flavus were screened by HPLC for their ability to produce aflatoxins (AF). The percentage of aflatoxigenic A. flavus isolates was 53%. Eight isolates produced AF, at concentrations ranging 0.7-2.9 ppb. Random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) molecular markers were used to genetically characterize isolates of A. flavus and to discriminate between the aflatoxigenic and non-aflatoxigenic isolates. RAPD and ISSR analysis revealed a high level of genetic diversity in the A. flavus population, which was useful for genetic characterization. The clustering in the RAPD and ISSR dendrograms obtained was unrelated to geographic origin. The RAPD and ISSR markers could not discriminate between aflatoxigenic and non-aflatoxigenic isolates, but the ISSR primers were somewhat better. PMID:25501147

  10. Resistance to Aspergillus flavus in maize and peanut: Molecular biology, breeding, environmental stress, and future perspectives

    Directory of Open Access Journals (Sweden)

    Jake C. Fountain

    2015-06-01

    Full Text Available The colonization of maize (Zea mays L. and peanut (Arachis hypogaea L. by the fungal pathogen Aspergillus flavus results in the contamination of kernels with carcinogenic mycotoxins known as aflatoxins leading to economic losses and potential health threats to humans. The regulation of aflatoxin biosynthesis in various Aspergillus spp. has been extensively studied, and has been shown to be related to oxidative stress responses. Given that environmental stresses such as drought and heat stress result in the accumulation of reactive oxygen species (ROS within host plant tissues, host-derived ROS may play an important role in cross-kingdom communication between host plants and A. flavus. Recent technological advances in plant breeding have provided the tools necessary to study and apply knowledge derived from metabolomic, proteomic, and transcriptomic studies in the context of productive breeding populations. Here, we review the current understanding of the potential roles of environmental stress, ROS, and aflatoxin in the interaction between A. flavus and its host plants, and the current status in molecular breeding and marker discovery for resistance to A. flavus colonization and aflatoxin contamination in maize and peanut. We will also propose future directions and a working model for continuing research efforts linking environmental stress tolerance and aflatoxin contamination resistance in maize and peanut.

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

    International Nuclear Information System (INIS)

    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 B2 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 B2 can arise independently of aflatoxin B1 and that, in this case, the branch in the pathway occurs at the versicolorins. Other metabolites charaterized were aflatoxin M2, norsolorinic acid, and averufin

  12. Epidural mass due to Aspergillus flavus causing spinal cord compression - A case report and brief update

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    Tendolkar U

    2005-01-01

    Full Text Available Aspergillus infection of the central nervous system (CNS is an uncommon disease. Most of the reported cases are of sinocranial spread and cases with contiguous spread to spinal cord from lung and other organs are uncommon. A case of pulmonary aspergillosis with extension to thoracic vertebrae forming a paraspinal mass resulting in neurological deficit due to Aspergillus flavus , is reported. The 43 year old patient did not have any obvious predisposing condition. He presented with loss of motor function and succumbed to the infection despite operative intervention and antifungal therapy. A brief update on CNS aspergillosis is presented along with detailed clinical, radiological and laboratory work up of the patient.

  13. Hygienic assessment of ionizing radiation effect on wheat contaminated with Aspergillus flavus

    International Nuclear Information System (INIS)

    Wheat contaminated with Aspergillus flavus fungus was irradited with doses of gamma radiation of up to 6000 Gy. It was found that while fungus growth is limited with increased doses of radiation, aflatoxin production increases. Aflatoxin production heavily depends on the moisture of the wheat. Toxicological and genetic tests of dominant lethal mutations were negative. Contaminated wheat irradiated with a dose of 6000 Gy may be used as feed for livestock. (M.D.)

  14. Inhibitory activity of compounds isolated from Polymnia sonchifolia on aflatoxin production by Aspergillus flavus

    Directory of Open Access Journals (Sweden)

    Pak Adriana

    2006-01-01

    Full Text Available Polymnia sonchifolia, commonly known as ";yacon";, was originally cultivated at Andes moutains in South America. Recently, the specie attracted worldwide attention because of its wide range of uses, for example in the control of diabetes melitus, besides the antifungal and pesticidal compounds were found in the leaves. This study describes the identification of two flavonoids: 3', 5, 7 trihydroxy-3, 4'-dimethoxyflavone (compound 1 and 3', 4', 5- trihydroxy-7-methoxy flavanone (compound 2 and two sesquiterpenes lactones: enhydrin (compound 3 and a mixture of enhydrin and uvedalin (compound 4 isolated from Polymnia sonchifolia leaves and their effects on the aflatoxin production by Aspergillus flavus. The identification of the compounds were achieved by ¹H and 13C NMR. All compounds were tested in different concentration, to evaluate the growth of Aspergillus flavus culture and the production of aflatoxin. The compound 1, at the concentration 15 mug/mL, inhibited 25% of the aflatoxin B1 production (p<0.01. The compound 4 inhibited 34% and 76% of the fungal growth and AFB1 production respectively. These results show that Polymnia sonchifolia can be used for the development of agents to control aflatoxin B1 production by Aspergillus flavus.

  15. Characterization of Iranian Nonaflatoxigenic Strains of Aspergillus flavus Based on Microsatellite-primed PCR

    Directory of Open Access Journals (Sweden)

    Mahmoud Houshyarfard

    2015-03-01

    Full Text Available Out of fifty-two Iranian nonaflatoxigenic strains of Aspergillus flavus, which were collected from various substrates (soil and kernel and sources (peanut, corn and pistachio, fifteen representatives were selected according to their different geographical origins (six provinces: Guilan and Golestan, Ardebil, Fars, Kerman and Semnan and vegetative compatibility groups (VCGs, IR1 to IR15 for microsatellite-primed PCR analysis. Two inter-simple sequence repeat (ISSR primers AFMPP and AFM13 were used to determine the polymorphism and the relationship among strain isolates. The A. flavus isolates were identified by their morphologies and their identities were confirmed by PCR amplification using the specific primer pair ITS1 and ITS4. The results revealed variations in the percentages of polymorphisms. In ISSR analysis, primers AFMPP and AFM13 generated a total of 18 and 23 amplicons among the fungal strains, which 12 (66.7% and 22 (95.7% were polymorphic, respectively. Cluster analysis of ISSR data was carried out by using 1 D DNA gel image analysis. The two dendrograms obtained through these markers showed six different clustering of testing nonaflatoxigenic A. flavus L strains, but we noted that some clusters were different in some cases. The microsatellite-primed PCR data revealed that the Iranian nonaflatoxigenic isolates of A. flavus were not clustered based on their origins and sources. This study is the first to characterize Iranian nonaflatoxigenic isolates of A. flavus using ISSR markers.

  16. Aspergillus flavus biomass in maize estimated by quantitative real-time polymerase chain reaction is strongly correlated with aflatoxin concentration

    Science.gov (United States)

    Aspergillus flavus causes Aspergillus ear rot of maize and produces aflatoxins. There are published assertions that resistance to aflatoxin accumulation and pathogen colonization are distinct traits in maize. However, the levels of colonization are difficult to characterize for a pathogen such as ...

  17. Genome Sequences of Eight Aspergillus flavus spp. and One A. parasiticus sp., Isolated from Peanut Seeds in Georgia

    Science.gov (United States)

    Wang, Xinye Monica; Palencia, Edwin R.

    2016-01-01

    Aspergillus flavus and A. parasiticus fungi produce carcinogenic mycotoxins in peanut seeds, causing considerable impact on both human health and the economy. Here, we report nine genome sequences of Aspergillus spp., isolated from Georgia peanut seeds in 2014. The information obtained will lead to further biodiversity studies that are essential for developing control strategies. PMID:27081142

  18. Genome Sequences of Eight Aspergillus flavus spp. and One A. parasiticus sp., Isolated From Peanut Seeds in Georgia

    Science.gov (United States)

    Aspergillus flavus and A. parasiticus fungi, carcinogen-mycotoxins producers, infect peanut seeds, causing considerable impact on both human health and the economy. Here we report 9 genome sequences of Aspergillus spp. isolated from peanut seeds. The information obtained will allow conducting biodiv...

  19. Cryptic Sexuality Influences Aflatoxigenicity in Aspergillus parasiticus and A. flavus

    Science.gov (United States)

    Ascomycetous fungi of the genus Aspergillus comprise a wide variety of species of biotechnological importance as well as pathogens and toxin producers. Recent studies report A. fumigatus to be heterothallic and possibly undergoing sexual reproduction. We therefore investigated whether compatible mat...

  20. Seventeen years of subcutaneous infection by Aspergillus flavus; eumycetoma confirmed by immunohistochemistry.

    Science.gov (United States)

    Ahmed, Sarah A; Abbas, Manal A; Jouvion, Gregory; Al-Hatmi, Abdullah M S; de Hoog, G Sybren; Kolecka, Anna; Mahgoub, El Sheikh

    2015-12-01

    Chronic subcutaneous infections caused by Aspergillus species are considered to be extremely rare. Because these fungi are among the most common laboratory contaminants, their role as eumycetoma causative agents is difficult to ascertain. Here, we report the first case of A. flavus eumycetoma confirmed by isolation, molecular identification and immunohistochemical analysis. Patient was a 55-year-old male from Sudan suffering from eumycetoma on his left foot for a period of 17 years. He developed swelling, sinuses and white grain discharge was observed. He has been operated nine times and was treated with several regimens of ketoconazole and itraconazole without improvement. Initial diagnosis based on histology and radiology was Scedosporium eumycetoma. However, examination of the biopsy revealed A. flavus, which was identified by molecular analysis and MALDI-TOF MS. Immunohistochemistry using antibody directed against Aspergillus species was positive. Because of the earlier treatment failures with ketoconazole and itraconazole, therapy with voriconazole was initiated. However, in vitro susceptibility testing yielded a lower Minimum Inhibitory Concentration (MIC) value for itraconazole (0.25 μg ml(-1) ) than for voriconazole (1 μg ml(-1) ). Based on the presented results, A. flavus can be considered as one of the agents of white-grain eumycetoma. PMID:26497138

  1. Molecular characterization of Aspergillus flavus and aflatoxin contamination of wheat grains from Saudi Arabia.

    Science.gov (United States)

    Al-Wadai, A S; Al-Othman, M R; Mahmoud, M A; Abd El-Aziz, A R M

    2013-01-01

    Twelve species belonging to six fungal genera were found to be associated with wheat (Triticum aestivum L.) grain samples collected from three main regions in Saudi Arabia. The most common genera (average frequency) were Aspergillus (14.3%), Fusarium (29.1%), Penicillium (9.3%), and Alternaria (8.2%). Nineteen isolates of Aspergillus flavus were screened for their ability to produce aflatoxins using HPLC. Thirteen isolates produced aflatoxins ranging from 0.5 to 2.6 µg/kg. Inter-simple sequence repeats (ISSR), and random amplified polymorphic DNA (RAPD) molecular markers were used, with the aim of genetically characterizing strains of A. flavus to discriminate between aflatoxigenic and non-aflatoxigenic isolates. RAPD and ISSR analysis revealed a high level of genetic diversity in the A. flavus population, useful for genetic characterization. Clustering based on RAPD and ISSR dendograms was unrelated to geographic origin. RAPD and ISSR markers were not suitable to discriminate aflatoxigenic and non-aflatoxigenic isolates, but ISSR primers were better compared to RAPD. PMID:24065675

  2. Effects of Nutrients in Substrates of Different Grains on Aflatoxin B1 Production by Aspergillus flavus

    Science.gov (United States)

    Liu, Jie; Sun, Lvhui; Zhang, Niya; Zhang, Jiacai; Guo, Jiao; Li, Chong; Rajput, Shahid Ali; Qi, Desheng

    2016-01-01

    The current study was to better understand the potential factors affecting aflatoxin B1 (AFB1) accumulation varies between different grains. The nutrient composition and contents of defatted substrates were determined; additionally, according to the nutrient content of the substrates, the effects of starch, soluble sugars, amino acids, and trace elements on AFB1 production and mycelial growth in Czapek-Dox medium were examined. These results verified that removal of lipids from ground substrates significantly reduced the substrate's potential for AFB1 production by Aspergillus flavus. Maltose, glucose, sucrose, arginine, glutamic acid, aspartic acid, and zinc significantly induced AFB1 production up to 1.7- to 26.6-fold. And stachyose more significantly promoted A. flavus growth than the other nutrients. Thus, this study demonstrated that, combined with the nutrients content of grains, in addition to lipids, sucrose, stachyose, glutamic acid, and zinc might play key roles in various grains that are differentially infected by A. flavus. Particularly, two new nutrients (arginine and stachyose) of the grains we found significantly stimulate AFB1 production and A. flavus growth, respectively. The results provide new concepts for antifungal methods to protect food and animal feed from AFB1 contamination. PMID:27294129

  3. Aflatoxins in Rice Artificially Contaminated with Aflatoxin-producing Aspergillus flavus under Natural Storage in Japan.

    Science.gov (United States)

    Sugihara, Satoshi; Doi, Hiroyuki; Kato, Masahiko; Mitoh, Yoshihiro; Tsuda, Toshihide; Ikeda, Satoru

    2016-06-01

    Aflatoxin (AFT) contamination is frequent in foods grown in tropical regions, including rice. Although AFTs are generally not found in temperate-region foods, global warming has affected typical temperate-region climates, potentially permitting the contamination of foods with AFT-producing Aspergillus flavus (A. flavus). Here we investigated the AFT production in rice during storage under natural climate conditions in Japan. We examined AFTs in brown rice and rough rice artificially contaminated with A. flavus for 1 year in Japan, and we subjected AFTs in white rice to the same treatment in airtight containers and examined the samples in warm and cold seasons, simulating the storage of white rice in general households. In the brown rice, AFTs increased after 2 months (March) and peaked after 9 months (October). The AFT contamination in the rough rice was minimal. After the polishing and cooking of the brown rice, AFTs were undetectable. In the white rice stored in airtight containers, AFTs increased after 1 month (August) and peaked after 2 months (September). Minimal AFTs were detected in the cold season. Thus, AFT contamination in rice may occur in temperate regions following A. flavus contamination. The storage of rice as rough rice could provide be useful for avoiding AFT contamination. PMID:27339205

  4. Data set for the mass spectrometry based exoproteome analysis of Aspergillus flavus isolates

    Directory of Open Access Journals (Sweden)

    Ramu Muthu Selvam

    2015-03-01

    Full Text Available Aspergillus flavus is one of the predominant causative organisms of mycotic keratitis in tropical parts of the world. Extracellular proteins are the earliest proteins that come in contact with the host and have a role in the infection process. Exoproteins of A. flavus isolated from infected cornea, sputum and a saprophyte were pooled and identified using high resolution mass spectrometry in order to get the total exoproteome from cultures isolated from different sources. A total of 637 proteins was identified from the pooled A. flavus exoproteome. Analysis based on GO annotations of the 637 identified proteins revealed that hydrolases form the predominant class of proteins in the exoproteome. Interestingly, a greater proportion of the exoproteins seem to be secreted through the non-classical pathways. This data represent the first in-depth analysis of the representative A. flavus exoproteome of a large set of isolates from distinct sources. This data have been deposited to the ProteomeXchange with identifier PXD001296.

  5. Evaluation of antifungal activity of Pittosporum undulatum L. essential oil against Aspergillus flavus and aflatoxin production Avaliação da atividade antifúngica do óleo essencial de Pittosporum undulatum L. em Aspergillus flavus e produção de aflatoxina

    Directory of Open Access Journals (Sweden)

    Rosane Tamara da Silva Medeiros

    2011-02-01

    Full Text Available The presence of mycotoxins as a result of fungal attack can occur before, after and during the harvest and storage operations on agricultural crops and food commodities. Considering the inhibitory property of essential plant oils on the mycelial development of fungi and the importance of Aspergillus flavus, the main producer of aflatoxins, this research was designed to evaluate the toxicity of essential oil from Pittosporum undulatum against A. flavus. The essential oils were obtained from P. undulatum leaves, collected in different months and analyzed by GC/MS. The oils were rich in hydrocarbon, monoterpenes and sesquiterpenes and it was observed a significant variation on the chemical composition of the essential oil of leaves at different months. Besides, the essential oils were tested against fungal growth and the results showed different spectrum of inhibition on A. flavus. However, the essential oils inhibited the aflatoxin B1 production.A presença de micotoxinas como resultado do ataque fúngico pode ocorrer antes, após e durante a colheita e também no armazenamento de grãos e alimentos. Considerando as propriedades inibitórias dos óleos essenciais de plantas no desenvolvimento do micélio dos fungos e a importâncias do Aspergillus flavus, principal produtor de aflatoxinas, relatou-se neste trabalho, a atividade tóxica do óleo essencial do Pittosporum undulatum em cultura de A. flavus. Os óleos essenciais de P. undulatum foram obtidos a partir de folhas coletadas em diferentes meses e analisado por CG/EM. Os óleos se mostraram ricos em hidrocarbonetos, monoterpenos e sesquiterpenos e foi observada uma significante variação na composição química destes óleos nos diferentes meses de coleta. Os óleos essenciais mostraram diferentes espectros de inibição do crescimento de A. flavus, porém todos foram capazes de inibir a produção de aflatoxina B1.

  6. 75 FR 9596 - Notice of Filing of a Pesticide Petition for Residues of a Aspergillus flavus AF36 on Corn Food...

    Science.gov (United States)

    2010-03-03

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY Notice of Filing of a Pesticide Petition for Residues of a Aspergillus flavus AF36 on Corn Food... residues of the antifungal ] agent, Aspergillus flavus AF36, in or on corn food and feed commodities....

  7. Recombinant expression and inhibition mechanism analysis of pectin methylesterase from Aspergillus flavus.

    Science.gov (United States)

    Jiang, Xiuping; Jia, Qiulei; Chen, Lei; Chen, Qi; Yang, Qing

    2014-06-01

    Phytopathogenic microorganisms can produce pectin methylesterase (PME) to degrade plant cell walls during plant invasion. This enzyme is thought to be a virulence factor of phytopathogens. In this work, PME from Aspergillus flavus (AFPME) was expressed in Pichia pastoris and an in vitro inhibitor study was performed. The purified AFPME with a yield of 52.2% was resolved as one band with a molecular mass of c. 40 kDa by SDS-PAGE. Optimal activity of the enzyme occurred at a temperature of 55 °C and a pH of 4.8. Epigallocatechin gallate (EGCG) strongly inhibited the activity of recombinant AFPME. The molecular docking analysis indicated that EGCG could form hydrogen bonds and π-π interactions with some amino acid residues in the active site of AFPME. Our studies provide a novel strategy for the control of the plant invasion of A. flavus. PMID:24766423

  8. Aflatoxin and Sclerotia Production in Clinical Isolates of Aspergillus Flavus Group

    Directory of Open Access Journals (Sweden)

    P Kordbacheh

    2008-07-01

    Full Text Available Backgrounds: To obtain information about clinical isolates of Aspergillus flavus group. Methods: We examined 55 isolates [45 clinical, 10 reference (6 from culture collections, 4 local reference] for toxicology, growth rates, and morphological and physiological characteristics. Modified Czapek Agar (CZ and Malt Extract Agar (MEA were used for observing microscopic morphology and measuring fungal structures. Two additional media, Potato Dextrose Agar (PDA and a modified Rice Agar (RA, were used to detect fluorescence under UV light. The presence of aflatoxin in culture extracts was confirmed by thin-layer chromatography (TLC. Results: 66.6% and 55.5% of clinical samples showed different shade of fluorescence on RA and PDA, respectively, after exposure to UV light. Fifteen (33.3% of the clinical isolates and 3 (30% of the reference strains produced sclerotia on Czapek Yeast Agar (CYA at 37° C. Sclerotia formation was promoted at 37°C in comparison with 28°C on CYA medium (P< 0.001. Five (11.11% of the clinical isolates, the Iranian A. flavus soil reference strain and A. parasiticus ATCC15517 were confirmed to be aflatoxiginc by TLC. From two clinical toxigenic isolates (of 5 which were fluorescence positive on PDA, only one produced fluorescence on RA after exposure to UV light. Moreover sclerotia production was observed in only 3 of 5 toxigenic isolates. Furthermore one isolate from a sinus specimen was identified as Aspergillus oryzae. This is believed to be the first report of sinusitis due to A. oryzae from Iran. Conclusion: Some of clinical A. flavus isolates could have aflatoxin and sclerotia producing ability, but not necessarily all aflatoxigenic A. flavus isolates are capable of producing sclerotia.

  9. Aspergillus flavus: A potential Bioremediator for oil contaminated soils

    Directory of Open Access Journals (Sweden)

    Y.Avasn Maruthi

    2013-02-01

    Full Text Available Biodegradation is cost-effective, environmentally friendly treatment for oily contaminated sites by the use of microorganisms. In this study, laboratory experiments were conducted to establish the performance of fungal isolates in degradation of organic compounds contained in soils contaminated with petrol and diesel. As a result of the laboratory screening, two natural fungal strains capable of degrading total organic carbons (TOC were prepared from isolates enriched from the oil contaminated sites. Experiments were conducted in Erlenmeyer flasks under aerobic conditions, with TOC removal percentage varied from 0.7 to 32% depending on strains type and concentration. Strains Phanerocheate chrysosporium and Aspergillus niger exhibited the highest TOC removal percentage of 32 and 21%, respectively, before nutrient addition. TOC removal rate was enhanced after addition of nutrients to incubated flasks. The highest TOC reduction (45% was estimated after addition of combination of nitrogen, phosphorus and sulphur to Phanerocheate chrysosporium strains. Results of experimental work carried out elucidate that the fungi like Phanerocheate chrysosporium and Aspergillus niger were capabled of producing enzymes at a faster rate to decompose the substrate hydrocarbon and released more CO2 and hence these potential fungi can be utilized effectively as agents of biodegradation in waste recycling process and Bioremediation of oil contaminated sites.

  10. Hydrophobic Effect of Amphiphilic Derivatives of Chitosan on the Antifungal Activity against Aspergillus flavus and Aspergillus parasiticus

    Directory of Open Access Journals (Sweden)

    Vera Ap. de Oliveira Tiera

    2013-04-01

    Full Text Available Low molecular weight amphiphilic derivatives of chitosan were synthesized, characterized and their antifungal activities against Aspergillus flavus and Aspergillus parasiticus were tested. The derivatives were synthesized using as starting material a deacetylated chitosan sample in a two step process: the reaction with propyltrimethyl-ammonium bromide (Pr, followed by reductive amination with dodecyl aldehyde. Aiming to evaluate the effect of the hydrophobic modification of the derivatives on the antifungal activity against the pathogens, the degree of substitution (DS1 by Pr groups was kept constant and the proportion of dodecyl (Dod groups was varied from 7 to 29% (DS2. The derivatives were characterized by 1H-NMR and FTIR and their antifungal activities against the pathogens were tested by the radial growth of the colony and minimum inhibitory concentration (MIC methods. The derivatives substituted with only Pr groups exhibited modest inhibition against A. flavus and A. parasiticus, like that obtained with deacetylated chitosan. Results revealed that the amphiphilic derivatives grafted with Dod groups exhibited increasing inhibition indexes, depending on polymer concentration and hydrophobic content. At 0.6 g/L, all amphiphilic derivatives having from 7.0 to 29% of Dod groups completely inhibited fungal growth and the MIC values were found to decrease from 4.0 g/L for deacetylated chitosan to 0.25–0.50 g/L for the derivatives. These new derivatives open up the possibility of new applications and avenues to develop effective biofungicides based on chitosan.

  11. Comparison of Aflatoxin B1 production by Aspergillus flavus and Aspergillus parasiticus under various conditions of temperature, light and pH

    Directory of Open Access Journals (Sweden)

    O Fani makk

    2013-07-01

    Full Text Available Abstract Background & aim: Aflatoxins are a large group of mycotoxins. The aim of the present study was the comparison of Aflatoxin B1 (AFB1 production by Aspergillus flavus (IR 111 and Aspergillus parasiticus (NRRL 2999 under various conditions of temperature, light, and pH. Methods: In this experimental study, twenty-four flasks were assigned for incubation of each of the fungi A. Flavus and parasiticus at 18, 24, 32 °C. Both flasks were maintained under conditions of light and darkness. The rate of (AFB1 produced by each groups, was measured by thin layer chromatography. Data were analyzed using descriptive statistical analysis (SPSS, version 16. Results: The lowest yield of (AFB1 produced by A. Flavus and parasiticus belonged to 32 °C and pH 6.5, respectively. On the other hand, the highest yield of toxin was observed at 24 °C and pH 6. The lighting effects were considerable. According to the studies on the adverse effects of light and the fermentation process, aflatoxin production increased in dark conditions. Conclusion: The results of study showed that A. Parasiticus (NRRL 2999 produced more aflatoxin than A. Flavus (IR 111. Key words: Aflatoxin B1, Aspergillus flavus, Aspergillus parasiticus

  12. Biotransformation of sucrose into 5-hydroxy-2-hydroxymethyl-γ-pirone by Aspergillus flavus

    Directory of Open Access Journals (Sweden)

    Nelson R. Ferreira

    2010-09-01

    Full Text Available The sucrose hydrolysis and the preference of consumption of glucose instead of fructose were investigated for the production of 5-hydroxy-2-hydroxymethyl-γ-pyrone (HHMP in the presence of Aspergillus flavus IOC 3974 cultivated in liquid Czapeck medium. Standardized 0.5g of pellets were transferred as inoculum into twelve conical flasks of 250 ml containing 100 ml of medium with different sucrose concentration, which was kept at 120 rpm and 28"C for 16 days without pH adjustment. Aliquots of 500μl of the broth culture were withdrawn at 24 h intervals and analyzed. The major yield of HHMP was 26g l-1 in 120g l-1 of sucrose. At these conditions, A. flavus produced an invertase capable of hydrolyzing 65% of total sucrose concentration in 24h, and an isomerase capable of converting fructose into glucose. In this work, it focused the preference for glucose and, then, of fructose by A. flavus and the strategy used to produce HHMP.Foram investigadas a hidrólise da sacarose e a preferência pela glicose frente à frutose no processo de produção do 5-hidroxi-2-hidroximetil-γ-pirona (HHMP na presença de Aspergillus flavus IOC 3974 cultivado em meio líquido Czapeck. Quantidades de 0,5g de pelletes foram utilizadas como inóculo. Doze frascos cônicos de 250 ml contendo 100 ml de meio de culturacom diferentes concentrações de sacarose foram utilizados.Os microrganismos foram cultivados a 120 rpm e 28"C por 16 dias sem ajuste do pH. O maior rendimento do HHMP foi 26g l-1em 120g l-1de sacarose. Nestas condições, A. flavus, foi capaz de produzir uma invertase possibilitando a hidrólise de 65% da concentração total de sacarose em 24 horas, conjuntamente com a produção de uma isomerase que foi capaz de converter a frutose em glicose. Este trabalho está focalizado preferencialmente no consumo da glicose frente à frutose por A. flavus e na estratégia de produção do HHMP.

  13. Biotransformation of chalcones by the endophytic fungus Aspergillus flavus isolated from Paspalum maritimum trin

    Energy Technology Data Exchange (ETDEWEB)

    Correa, Marivaldo J.C.; Nunes, Fatima M.; Bitencourt, Heriberto R.; Borges, Fabio C.; Guilhon, Giselle M.S.P.; Arruda, Mara S.P.; Marinho, Andrey M. R.; Santos, Alberdan S.; Alves, Claudio N.; Santos, Lourivaldo S., E-mail: lss@ufpa.b [Universidade Federal do Para (IQ/FEQ/UFPA), Belem, PA (Brazil). Inst. de Tecnologia. Faculdade de Engenharia Quimica; Brasil, Davi S.B. [Universidade Federal do Para (PPGQ/IQ/UFPA), Belem, PA (Brazil). Inst. de Quimica. Programa de Pos-Graduacao em Quimica

    2011-07-01

    The fungus Aspergillus flavus isolated as endophytic of the plant Paspalum maritimum Trin. was evaluated for its potential application in biotransformation reactions. The compounds chalcone (1), 3,4,5-trimethoxychalcone (2) and 2,3,4,4'-tetramethoxy chalcone (3) were biotransformed, respectively, in dihydrochalcone (4), 3,4,5-trimethoxydihydrochalcone (5) and 2,3,4,4'-tetramethoxydihydrochalcone (6). The structures were elucidated by spectroscopic methods including 1D and 2D NMR techniques, and MS analysis. The dihydrochalcones 5 and 6 are new compounds. (author)

  14. Novel regulation of aflatoxin B1 biosynthesis in Aspergillus flavus by piperonal.

    Science.gov (United States)

    Park, Eun-Sil; Bae, In Kyung; Kim, Ho Jin; Lee, Sung-Eun

    2016-08-01

    The present study investigated its inhibitory role in aflatoxin (AF) biosynthesis. Treating only AFB1- and B2-producing Aspergillus flavus with piperonal completely inhibited AFB1 production with high sclerotial formation, resulting in 20-fold higher AFG2 production. On the other hand, benzodioxole and eugenol suppressed AFB1 production without AFG formation, while methyleugenol showed potent inhibition of AFB1 production with slight production of AFG1. These results indicate that natural products may change aflatoxin biosynthesis, and highlight a novel regulation of AFG2 production by piperonal. It is the first report for chemical regulation on AFG2 production in non-AFG producing-aspergilli. PMID:26273991

  15. The T788G Mutation in the cyp51C Gene Confers Voriconazole Resistance in Aspergillus flavus Causing Aspergillosis

    OpenAIRE

    Liu, Wei; Sun, Yi; Chen, Wei; Liu, Weixia; Wan, Zhe; Bu, Dingfang; Li, Ruoyu

    2012-01-01

    With voriconazole (VRC) being approved as the first choice in treating invasive aspergillosis (IA) and its increasing use in treatment, a VRC-resistant strain of Aspergillus flavus, the second leading cause of IA after Aspergillus fumigatus, has emerged. The VRC-resistant strain of A. flavus was isolated for the first time from the surgical lung specimen of an IA patient with no response to VRC therapy. In order to ascertain the mechanism of VRC resistance, the azole target enzyme genes in th...

  16. The Inhibitory Effects of Curcuma longa L. Essential Oil and Curcumin on Aspergillus flavus Link Growth and Morphology

    OpenAIRE

    Flávio Dias Ferreira; Simone Aparecida Galerani Mossini; Francine Maery Dias Ferreira; Carla Cristina Arrotéia; Christiane Luciana da Costa; Celso Vataru Nakamura; Miguel Machinski Junior

    2013-01-01

    The essential oil from Curcuma longa L. was analysed by GC/MS. The major components of the oil were ar-turmerone (33.2%), α -turmerone (23.5%) and β -turmerone (22.7%). The antifungal activities of the oil were studied with regard to Aspergillus flavus growth inhibition and altered morphology, as preliminary studies indicated that the essential oil from C. longa inhibited Aspergillus flavus Link aflatoxin production. The concentration of essential oil in the culture media ranged from 0.01% to...

  17. Kojic acid production from cocoa juice by Aspergillus flavus entrapped in calcium alginate.

    Science.gov (United States)

    el-Sharkawy, S H

    1995-06-01

    Sixteen microorganisms of Aspergillus strains were screened for production of kojic acid using cocoa juice as carbon source. Only Aspergillus flavus ATCC 9179 was found to produce the acid in low yield (22 mg/ml). Calcium alginate immobilization of the cells was used under optimum conditions to maximize the yield of kojic acid (60 mg/ml). Cultures were incubated in the medium with 50% of cocoa juice added in pulses of 8 ml each every 96 hours, and 4% methanol, pH 3.5, 150 rpm, 26 degrees C for three weeks. The incubations were monitored by thin layer and high pressure liquid chromatography. Kojic acid was extracted from the culture broth by organic solvent, concentrated and crystallized. The chemical identity of kojic acid was determined by HPLC, MS, 1H- and 13C-NMR spectroscopy. PMID:7546538

  18. Self-sufficient redox biotransformation of lignin-related benzoic acids with Aspergillus flavus.

    Science.gov (United States)

    Palazzolo, Martín A; Mascotti, María L; Lewkowicz, Elizabeth S; Kurina-Sanz, Marcela

    2015-12-01

    Aromatic carboxylic acids are readily obtained from lignin in biomass processing facilities. However, efficient technologies for lignin valorization are missing. In this work, a microbial screening was conducted to find versatile biocatalysts capable of transforming several benzoic acids structurally related to lignin, employing vanillic acid as model substrate. The wild-type Aspergillus flavus growing cells exhibited exquisite selectivity towards the oxidative decarboxylation product, 2-methoxybenzene-1,4-diol. Interestingly, when assaying a set of structurally related substrates, the biocatalyst displayed the oxidative removal of the carboxyl moiety or its reduction to the primary alcohol whether electron withdrawing or donating groups were present in the aromatic ring, respectively. Additionally, A. flavus proved to be highly tolerant to vanillic acid increasing concentrations (up to 8 g/L), demonstrating its potential application in chemical synthesis. A. flavus growing cells were found to be efficient biotechnological tools to perform self-sufficient, structure-dependent redox reactions. To the best of our knowledge, this is the first report of a biocatalyst exhibiting opposite redox transformations of the carboxylic acid moiety in benzoic acid derivatives, namely oxidative decarboxylation and carboxyl reduction, in a structure-dependent fashion. PMID:26445878

  19. Influence of relative humidity on radiosensitivity of Aspergillus flavus Link. infecting cocoa beans

    International Nuclear Information System (INIS)

    The first part of this paper deals with the moisture sorption isotherms of dried cocoa beans under different relative humidities of 55, 65, 75, 85 or 95%. The second part evaluates the effects of relative humidity (RH), initial moisture content (m.c.) of cocoa beans, and different radiation exposure doses (0, 250, 350, 450, 500 or 550 krad) on Aspergillus flavus spore inoculated cocoa beans kept in fixed RH environmental chamber of 75 or 85% RH post-irradiation for forty days. The results discussed suggest that the m.c. of beans increased from an initial level of 6.4% to 7, 7.8 and 8.9% at 55, 65, and 75% respectively, after a storage period of 6-8 days. However, beans stored under 85% or 95% RH continued to absorb moisture from their respective environments indefinitely during the 64-day storage period. Furthermore, the ambient relative humidity to which the beans are subjected before or after irradiation significantly affect the radiosensitivity of toxigenic A. flavus; the differences in such radiosensitivity are influenced by either the available moisture or the initial m.c. of the beans to the inoculum. The authors conclude from their study that high environmental RH increased the radio-resistance of A. flavus spores making it difficult to establish a radiation decontamination level of practical value under a tropical environment with high ambient relative humidity. (author)

  20. Influence of Relative Humidity on Radiosensitivity of Aspergillus Flavus Link Infecting Cocoa Beans

    International Nuclear Information System (INIS)

    The first part of this paper deals with the moisture sorption isotherms of dried cocoa beans under different relative humidities of 55, 65, 75, 85 or 95%. The second part evaluates the effects of relative humidity (RH), initial moisture content (m.c.) of cocoa beans, and different radiation exposure doses (0, 250, 350, 450, 500 or 550 krad) on Aspergillus flavus spore inoculated cocoa beans kept in fixed RH environmental chamber of 75 or 85% RH postirradiation for forty days. The results discussed suggest that the m.c. of beans increased from an initial level of 6.4% to 7, 7.8 and 8.9% at 55, 65, and 75% respectively, after a storage period of 6-8 days. However, beans stored under 85% or 95% RH continued to absorb moisture from their respective environments indefinitely during the 64-day storage period. Furthermore, the ambient relative humidity to which the beans are subjected before or after irradiation significantly affect the radiosensitivity of toxigenic A. flavus; the differences in such radiosensitivity are influenced by either the available moisture or the initial m.c. of the beans to the inoculum. The authors conclude from their study that high environmental RH increased the radio-resistance of A. flavus spores making it difficult to establish a radiation decontamination level of practical value under a tropical environment with high ambient relative humidity. (author)

  1. Chemical properties of Aspergillus flavus-infected soybean seeds exposed to gamma-irradiation during storage

    International Nuclear Information System (INIS)

    The aim of the present study was to examine the chemical properties of Aspergillus flavus-infected soybean seeds exposed to different levels of gamma-irradiation; 0 1, 3 and 5 kGy, during storage. The results revealed that there was no effect of irradiation at different dose levels on moisture, protein, total lipids and amino acids content of the seeds for overall 60 days of storage under ambient temperature. At zero time, irradiation of A. flavus- infected-soybean seeds at 5.0 kGy caused a slight increase in peroxide value, no change in acid value, a slight decrease in saponification and iodine values in the crude oil extracted from the seeds. An increase in saturated fatty acids associated with a decrease in un-saturated fatty acids was also observed in the oil extracted from the seeds. Furthermore, at dose level 5 kGy the fungus growth was completely inhibited and there was no detection of aflatoxin B1 after 60 days of storage. It is concluded that gamma-irradiation of A. flavus-infected soybean seeds at dose level 5 kGY is sufficient to inhibit fungus growth and aflatoxin production over a storage period of 60 days without changes in major chemical properties of the seeds and the oil extracted from seeds

  2. Simple and highly discriminatory VNTR-based multiplex PCR for tracing sources of Aspergillus flavus isolates.

    Directory of Open Access Journals (Sweden)

    Dong Ying Wang

    Full Text Available Aspergillus flavus is second only to A. fumigatus in causing invasive aspergillosis and it is the major agent responsible for fungal sinusitis, keratitis and endophthalmitis in many countries in the Middle East, Africa and Southeast Asia. Despite the growing challenge due to A. flavus, data on the molecular epidemiology of this fungus remain scarce. The objective of the present study was to develop a new typing method based on the detection of VNTR (Variable number tandem repeat markers. Eight VNTR markers located on 6 different chromosomes (1, 2, 3, 5, 7 and 8 of A. flavus were selected, combined by pairs for multiplex amplifications and tested on 30 unrelated isolates and six reference strains. The Simpson index for individual markers ranged from 0.398 to 0.818. A combined loci index calculated with all the markers yielded an index of 0.998. The MLVA (Multiple Locus VNTR Analysis technique proved to be specific and reproducible. In a second time, a total of 55 isolates from Chinese avian farms and from a Tunisian hospital have been evaluated. One major cluster of genotypes could be defined by using the graphing algorithm termed Minimum Spanning Tree. This cluster comprised most of the isolates collected in an avian farm in southern China. The MLVA technique should be considered as an excellent and cost-effective typing method that could be used in many laboratories without the need for sophisticated equipment.

  3. Heterologous, Expression, and Characterization of Thermostable Glucoamylase Derived from Aspergillus flavus NSH9 in Pichia pastoris

    Science.gov (United States)

    Karim, Kazi Muhammad Rezaul; Hossain, Md. Anowar; Sing, Ngieng Ngui; Mohd Sinang, Fazia; Hussain, Mohd Hasnain Md.; Roslan, Hairul Azman

    2016-01-01

    A novel thermostable glucoamylase cDNA without starch binding domain (SBD) of Aspergillus flavus NSH9 was successfully identified, isolated, and overexpressed in Pichia pastoris GS115. The complete open reading frame of glucoamylase from Aspergillus flavus NSH9 was identified by employing PCR that encodes 493 amino acids lacking in the SBD. The first 17 amino acids were presumed to be a signal peptide. The cDNA was cloned into Pichia pastoris and the highest expression of recombinant glucoamylase (rGA) was observed after 8 days of incubation period with 1% methanol. The molecular weight of the purified rGA was about 78 kDa and exhibited optimum catalytic activity at pH 5.0 and temperature of 70°C. The enzyme was stable at higher temperature with 50% of residual activity observed after 20 min at 90°C and 100°C. Low concentration of metal (Mg++, Fe++, Zn++, Cu++, and Pb++) had positive effect on rGA activity. This rGA has the potential for use and application in the saccharification steps, due to its thermostability, in the starch processing industries.

  4. CEMARAN ASPERGILLUS FLAVUS DAN AFLATOKSIN PADA RANTAI DISTRIBUSI PRODUK PANGAN BERBASIS JAGUNG DAN FAKTOR YANG MEMPENGARUHINYA [Contamination of Aspergillus flavus and Aflatoxin at Distribution Chain of Maize Based Food Product and its Influencing Factors

    Directory of Open Access Journals (Sweden)

    Harsi D. Kusumaningrum*

    2010-12-01

    Full Text Available Aflatoxin is a human carcinogen, produced by fungus Aspergillus flavus that frequently contaminates maize. Analysis of A. flavus by plate counting and aflatoxin by Thin Layer Chromatography were performed on 104 samples and 25 samples, respectively, of maize grain and maize based food products from different places in Bogor-West Java, Boyolali-Central Java and Bojonegoro-East Java. These regions support significant number of maize production in Java. Forty percent of the samples were contaminated by A. flavus, whereas aflatoxin level of higher than 20 ppb was found in 4 of 25 samples. The highest contamination level of A. flavus was found at the collector trader that often stored the maize grain in average of 15 days, at room temperature. There was a significant correlation between the length of storage as well as relative humidity with the contamination levels of A. flavus. Significant correlation was also found between the contamination levels of A. flavus with the level of aflatoxin in maize grain. However, no significant correlation was found between the aflatoxin level and the contamination levels of A. flavus in the processed maize based food products.

  5. Buckwheat achenes antioxidant profile modulates Aspergillus flavus growth and aflatoxin production.

    Science.gov (United States)

    Chitarrini, G; Nobili, C; Pinzari, F; Antonini, A; De Rossi, P; Del Fiore, A; Procacci, S; Tolaini, V; Scala, V; Scarpari, M; Reverberi, M

    2014-10-17

    Buckwheat (Fagopyrum spp.) is a "pseudo-cereal" of great interest in the production of healthy foods since its flour, derived from achenes, is enriched with bioactive compounds and, due to the absence of gluten, may be used in composition of celiac diets. Amongst buckwheat species, F. tataricum achenes possess a larger amount of the antioxidant flavenol rutin than the common buckwheat F. esculentum. Ongoing climate change may favor plant susceptibility to the attack by pathogenic, often mycotoxigenic, fungi with consequent increase of mycotoxins in previously unexploited feeds and foodstuffs. In particular, Aspergillus flavus, under suitable environmental conditions such as those currently occurring in Italy, may produce aflatoxin B1 (AFB1), the most carcinogenic compound of fungal origin which is classified by IARC as Category 1. In this study, the viable achenes of two buckwheat species, F. tataricum (var. Golden) and F. esculentum (var. Aelita) were inoculated with an AFB1-producing A. flavus NRRL 3357 to analyze their relative performances against fungal invasion and toxin contamination. Notably, we sought the existence of a correlation between the amount of tocols/flavonols in the achenes of buckwheat, infected and non-infected with A. flavus, and to analyze the ability of the pathogen to grow and produce toxin during achene infection. Results suggest that achenes of F. tataricum, the best producer of antioxidant compounds in this study, are less susceptible to A. flavus infection and consequently, but not proportionally, to mycotoxin contamination compared with F. esculentum. Moreover, rutin-derived quercetin appears to be more efficient in inhibiting aflatoxin biosynthesis than the parent compound. PMID:25108759

  6. Dry Heat and Radiation Combination Effects on Aspergillus Flavus Link. Infecting Cocoa Beans

    International Nuclear Information System (INIS)

    The paper deals with the effect of heat and radiation combination treatments on the control of microbial spoilage of cocoa beans caused by toxigenic Aspergillus flavus Link. The heat and radiation sources were from dry air oven heat and 60Co gammaceli 220 irradiator, respectively. The radiation doses used were either 0, 50, 100, 150 or 200 krad, with combined heat temperatures of 30, 60 or 90°C. At each temperature level three different exposure time intervals of either 15 min, 30 min or 60 min respectively, were used. Two reversible sequential heat/radiation combination effects were evaluated.. The first sequence involved cocoa beans inoculated with A. flavus spores exposed first to dry heat at pre-determined temperature heat exposure time, followed by radiation treatment, then retention of samples in a constant humidity environmental chamber set at 80% for daily observation up to forty days post-treatment. The second sequence involved exposure of the inoculated beans first to radiation, then to heat before retention under fixed RH for observation. From their results, the authors arrive at four conclusions: first, that there is a critical radiation/heat combination range (200, 150 and 100 krad/90°C for 15 min) that significantly decontaminates (less than 5% mouldiness) A. flavus infected cocoa beans even under high relative humidity (80% RH) environment; second, that a temperature level of 90°C combined with 200, 150 or 100 krad maximizes such effect but the heat exposure time is a major factor; third, that low heat temperature ranges of 30 or 60°C, combined with low radiation dosages of 150 krad or below, enhance the rate of A. flavus spoilage effects of cocoa beans; and, lastly, that the sequence of exposure of the inoculated cocoa beans to heat/radiation combination influenced the spore germination; exposure to heat before radiation would sensitize the spores (200 krad/90°C) but results in an increased radioresistance. (author)

  7. Dry heat and radiation combination effects on Aspergillus flavus Link. infecting cocoa beans

    International Nuclear Information System (INIS)

    The paper deals with the effect of heat and radiation combination treatments on the control of microbial spoilage of cocoa beans caused by toxigenic Aspergillus flavus Link. The heat and radiation sources were from dry air oven heat and 60Co gammacell 220 irradiator, respectively. The radiation doses used were either 0, 50, 100, 150 or 200 krad, with combined heat temperatures of 30, 60 or 900C. At each temperature level three different exposure time intervals of either 15 min, 30 min or 60 min respectively, were used. Two reversible sequential heat/radiation combination effects were evaluated. The first sequence involved cocoa beans inoculated with A. flavus spores exposed first to dry heat at pre-determined temperature heat exposure time, followed by radiation treatment, then retention of samples in a constant humidity environmental chamber set at 80% for daily observation up to forty days post-treatment. The second sequence involved exposure of the inoculated beans first to radiation, then to heat before retention under fixed RH for observation. From their results, the authors arrive at four conclusions: first, that there is a critical radiation/heat combination range (200, 150 and 100 krad/900C for 15 min) that significantly decontaminates (less than 5% mouldiness) A. flavus infected cocoa beans even under high relative humidity (80% RH) environment; second, that a temperature level of 900C combined with 200, 150 or 100 krad maximizes such effect but the heat exposure time is a major factor; third, that low heat temperature ranges of 30 or 600C, combined with low radiation dosages of 150 krad or below, enhance the rate of A. flavus spoilage effects of cocoa beans; and, lastly, that the sequence of exposure of the inoculated cocoa beans to heat/radiation combination influenced the spore germination; exposure to heat before radiation would sensitize the spores (200 krad/900C) but results in an increased radioresistance. (author)

  8. Toxicidade de óleos essenciais de alho e casca de canela contra fungos do grupo Aspergillus flavus Evaluation of essential oils from Allium sativum and Cinnamomum zeilanicum and their toxicity against fungi of the Aspergillus flavus group

    Directory of Open Access Journals (Sweden)

    Elson de C. Viegas

    2005-12-01

    Full Text Available Diante da propriedade inibitória de óleos essenciais vegetais sobre o desenvolvimento micelial de fungos e da importância das espécies do grupo Aspergillus flavus, que apresentam potencial para síntese de aflatoxina, este trabalho teve como objetivo avaliar in vitro a toxicidade de óleos essenciais vegetais contra fungos do grupo A. flavus, isolados a partir da cultura do amendoim. Inicialmente, foi avaliada a toxicidade de oito óleos essenciais vegetais no desenvolvimento micelial de dois isolados do grupo A. flavus, em comparação ao fungicida sintético benomyl. Em seguida, foi avaliada a toxicidade dos óleos de casca de canela (Cinnamomum zeilanicum Breym. e de bulbilho de alho (Allium sativum L. contra 37 isolados do grupo A. flavus, durante 12 meses. A maior inibição do desenvolvimento micelial de A. flavus foi obtida com o emprego dos óleos essenciais de casca de canela e de bulbilho de alho, e o efeito inibitório variou com o isolado testado.Considering the inhibitory property of essential plant oils on the mycelial development of fungi, and the importance of Aspergillus flavus-like fungi which may produce aflatoxins, this research was designed to evaluate the toxicity of essential oils against fungi belonging to the group A. flavus isolated from peanut crops. The toxicity of eight essential oils against two isolates of A. Flavuslike fungi was evaluated in comparison to the synthetic fungicide benomyl. The toxicity of Cinnamomum zeilanicum Breym. and Allium sativum L. essential oils was also evaluated against 37 fungal isolates for a period of 12 months. The highest inhibition of the mycelial development of A. flavus was obtained with cinnamon and garlic essential oils. The inhibitory effect on growth was variable according to the fungal isolate.

  9. Spinal osteomyelitis due to Aspergillus flavus in a child: a rare complication after haematopoietic stem cell transplantation

    International Nuclear Information System (INIS)

    We report the case of a child affected by acute myeloid leukaemia who was treated with allogeneic haematopoietic stem cell transplantation and developed cervicothoracic spinal osteomyelitis due to Aspergillus flavus. The diagnosis was difficult on a clinical basis, but made possible by conventional radiography and MRI. (orig.)

  10. Spinal osteomyelitis due to Aspergillus flavus in a child: a rare complication after haematopoietic stem cell transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Beluffi, Giampiero [Fondazione IRCCS Policlinico ' S.Matteo' , Section of Paediatric Radiology, Department of Radiodiagnosis, Pavia PV (Italy); Bernardo, Maria E.; Locatelli, Franco [University of Pavia, Fondazione IRCCS Policlinico ' S.Matteo' , Department of Paediatric Haematology/Oncology, Pavia (Italy); Meloni, Giulia [University of Pavia, Fondazione IRCCS Policlinico ' S.Matteo' , Institute of Radiology, Pavia (Italy); Spinazzola, Angelo [Fondazione IRCCS Policlinico ' S.Matteo' , Section of Paediatric Radiology, Department of Radiodiagnosis, Pavia PV (Italy); Ospedale Maggiore, Crema CR (Italy)

    2008-06-15

    We report the case of a child affected by acute myeloid leukaemia who was treated with allogeneic haematopoietic stem cell transplantation and developed cervicothoracic spinal osteomyelitis due to Aspergillus flavus. The diagnosis was difficult on a clinical basis, but made possible by conventional radiography and MRI. (orig.)

  11. Proteomic analysis of the maize rachis: Potential roles of constitutive and induced proteins in resistance to Aspergillus flavus and aflatoxin

    Science.gov (United States)

    Infection of the maize (Zea mays L.) with aflatoxigenic fungus Aspergillus flavus and consequent contamination with carcinogenic aflatoxin is a persistent and serious agricultural problem causing disease and significant crop losses worldwide. The rachis (cob) is an important structure of maize ear ...

  12. Inhibition of Aspergillus flavus in soil by antagonistic Pseudomonas strains reduces the potential for airborne spore dispersal

    Science.gov (United States)

    Pseudomonas chlororaphis strain JP1015 and Pseudomonas fluorescens strain JP2175 were previously isolated from Mississippi cornfield soil samples and selected for their growth inhibition of Aspergillus flavus in laboratory culture. In this study, the antifungal activity of these bacterial strains a...

  13. 77 FR 14287 - Aspergillus flavus AF36; Amendment to an Exemption From the Requirement of a Tolerance

    Science.gov (United States)

    2012-03-09

    ... Aspergillus flavus AF36 on pistachio (see the Federal Register of May 23, 2007 (72 FR 28868) (FRL-8129-4)) and...) 305-5805. II. Background and Statutory Findings In the Federal Register of April 20, 2011 (76 FR 22067... Register of July 14, 2003 (68 FR 41535) (FRL-7311-6). ``Those health effects data were the basis...

  14. 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...

  15. Fluorescent viability stains to probe the metabolic status of aflatoxigenic fungus in dual culture of Aspergillus flavus and Pichia anomala

    Science.gov (United States)

    The metabolic activity of aflatoxigenic fungus, Aspergillus flavus co-cultured with a biocontrol yeast, Pichia anomala was examined using several vital stains. Both the FUN-1 stain and the combined use of DiBAC4(5) with CDFA-AM stains demonstrated that P. anomala inactivated the ATP generating syst...

  16. The Stress Response Regulator AflSkn7 Influences Morphological Development, Stress Response, and Pathogenicity in the Fungus Aspergillus flavus

    Science.gov (United States)

    Zhang, Feng; Xu, Gaopo; Geng, Longpo; Lu, Xiaoyan; Yang, Kunlong; Yuan, Jun; Nie, Xinyi; Zhuang, Zhenhong; Wang, Shihua

    2016-01-01

    This study focused on AflSkn7, which is a stress response regulator in the aflatoxin-producing Aspergillus flavus. The ΔAflSkn7 mutants exhibited partially defective conidial formation and a complete inability to generate sclerotia, indicating AflSkn7 affects A. flavus asexual and sexual development. The mutants tolerated osmotic stress but were partially susceptible to the effects of cell wall stress. Additionally, the ΔAflSkn7 mutants were especially sensitive to oxidative stress. These observations confirmed that AflSkn7 influences oxidative stress responses rather than osmotic stress responses. Additionally, AflSkn7 was observed to increase aflatoxin biosynthesis and seed infection rates. These results indicate AflSkn7 affects A. flavus morphological development, stress response, aflatoxin production, and pathogenicity. The results of this study may facilitate the development of new methods to manage A. flavus infections. PMID:27399770

  17. Menadione-Induced Oxidative Stress Re-Shapes the Oxylipin Profile of Aspergillus flavus and Its Lifestyle

    Directory of Open Access Journals (Sweden)

    Marco Zaccaria

    2015-10-01

    Full Text Available Aspergillus flavus is an efficient producer of mycotoxins, particularly aflatoxin B1, probably the most hepatocarcinogenic naturally-occurring compound. Although the inducing agents of toxin synthesis are not unanimously identified, there is evidence that oxidative stress is one of the main actors in play. In our study, we use menadione, a quinone extensively implemented in studies on ROS response in animal cells, for causing stress to A. flavus. For uncovering the molecular determinants that drive A. flavus in challenging oxidative stress conditions, we have evaluated a wide spectrum of several different parameters, ranging from metabolic (ROS and oxylipin profile to transcriptional analysis (RNA-seq. There emerges a scenario in which A. flavus activates several metabolic processes under oxidative stress conditions for limiting the ROS-associated detrimental effects, as well as for triggering adaptive and escape strategies.

  18. A protective endophyte of maize: Acremonium zeae antibiotics inhibitory to Aspergillus flavus and Fusarium verticillioides.

    Science.gov (United States)

    Wicklow, Donald T; Roth, Shoshannah; Deyrup, Stephen T; Gloer, James B

    2005-05-01

    The maize endophyte Acremonium zeae is antagonistic to kernel rotting and mycotoxin producing fungi Aspergillus flavus and Fusarium verticillioides in cultural tests for antagonism, and interferes with A. flavus infection and aflatoxin contamination of preharvest maize kernels. Chemical studies of an organic extract from maize kernel fermentations of Acremonium zeae (NRRL 13540), which displayed significant antifungal activity against Aspergillus flavus and F. verticillioides, revealed that the metabolites accounting for this activity were two newly reported antibiotics pyrrocidines A and B. Pyrrocidines were detected in fermentation extracts for 12 NRRL cultures of Acremonium zeae isolated from maize kernels harvested in Illinois (4/4 cultures), North Carolina (5/5), Georgia (1/2) and unrecorded locations within the USA (2/2). Pyrrocidine B was detected by LCMSMS in whole symptomatic maize kernels removed at harvest from ears of a commercial hybrid that were wound-inoculated in the milk stage with A. zeae (NRRL 13540) or (NRRL 13541). The pyrrocidines were first reported from the fermentation broth of an unidentified filamentous fungus LL-Cyan426, isolated from a mixed Douglas Fir hardwood forest on Crane Island Preserve, Washington, in 1993. Pyrrocidine A exhibited potent activity against most Gram-positive bacteria, including drug-resistant strains, and was also active against the yeast Candida albicans. In an evaluation of cultural antagonism between 13 isolates of A. zeae in pairings with A. flavus (NRRL 6541) and F. verticillioides (NRRL 25457), A. zeae (NRRL 6415) and (NRRL 34556) produced the strongest reaction, inhibiting both organisms at a distance while continuing to grow through the resulting clear zone at an unchanged rate. Maximum colony diameters for A. zeae (NRRL 6415) and (NRRL 13540), on potato dextrose agar after 14 d, were attained within the range of 25-30 degrees C, with less growth recorded at 15 degrees and 37.5 degrees and no growth at 5

  19. Effect of dietary intervention on the performance and biochemical indices of broilers challenged with Aspergillus flavus

    Directory of Open Access Journals (Sweden)

    S. A. Bolu,

    2011-05-01

    Full Text Available A study was conducted to determine the effects of dietary interventions of vitamins A, C, methionine and lysine singly and their combination on broilers challenged with Aspergillus flavus. The interventions were Vitamins A and C (A+C, methionine and lysine (METH+LYS and their combination (A+C+METH+LYS. The experiment which was conducted for 8 weeks employed a completely randomized design. Feed intake, weight gain, nutrient retention and feed conversion efficiency were significantly influenced (P<0.05 by dietary supplementation of the Aspergillus challenged birds. Highest feed intake (42.81 g/bird/day was observe for Aspergillus challenged birds supplemented with A+C+METH+LYS which compared favourably with the positive control birds (42.48 g/bird/day. The lowest feed intake was observed for the negative control birds (Aspergillus challenged without dietary intervention. Weight gain was highest for the positive control bird (20.14 g/bird/day. This value was similar to the value obtained for Aspergillus challenged birds supplemented with A+C+METH+LYS. Lowest weight gain was observed in the negative control birds (12.44 g/bird/day. These birds also recorded significantly (P<0.05 lowest feed conversion efficiency (3.09. Haematological and serum indices showed no significant differences, however, higher lymphocytes values were observed in challenged birds with dietary intervention. As a general immune modulator, vitamins A and C with lysine and methionine may be an attractive alternative to the on-farm use of vaccines in poultry in the management of aspergillosis.

  20. Expression of Genes by Aflatoxigenic and Nonaflatoxigenic Strains of Aspergillus flavus Isolated from Brazil Nuts.

    Science.gov (United States)

    Baquião, Arianne Costa; Rodriges, Aline Guedes; Lopes, Evandro Luiz; Tralamazza, Sabina Moser; Zorzete, Patricia; Correa, Benedito

    2016-08-01

    The aims of the present study were to monitor the production of aflatoxin B1 (AFB1) and mycelial growth, and to evaluate the expression of genes directly and indirectly involved in the biosynthesis of aflatoxins by Aspergillus flavus isolated from Brazil nuts. Six previously identified A. flavus strains were grown on coconut agar at 25°C for up to 10 days. Mycotoxins were separated by high-performance liquid chromatography and fungal growth was measured daily using the diametric mycelial growth rate. Transcriptional analysis was performed by real-time polymerase chain reaction (PCR) after 2 and 7 d of incubation using specific primers (aflR, aflD, aflP, lipase, metalloprotease, and LaeA). Three (50%) of the six A. flavus isolates produced AFB1 (ICB-1, ICB-12, and ICB-54) and three (50%) were not aflatoxigenic (ICB-141, ICB-161, and ICB-198). Aflatoxin production was observed from d 2 of incubation (1.5 ng/g for ICB-54) and increased gradually with time of incubation until d 10 (15,803.6 ng/g for ICB-54). Almost all A. flavus isolates exhibited a similar gene expression pattern after 2 d of incubation (p > 0.10). After 7 d of incubation, the LaeA (p < 0.05) and metalloprotease (p < 0.05) genes were the most expressed by nonaflatoxigenic strains, whereas aflatoxigenic isolates exhibited higher expression of the aflR (p < 0.05) and aflD genes (p < 0.05). Our results suggest that the expression of aflR and aflD is correlated with aflatoxin production in A. flavus and that overexpression of aflR could affect the transcriptional and aflatoxigenic pattern (ICB-54). Elucidation of the molecular mechanisms that regulate the secondary metabolism of toxigenic fungi may permit the rational silencing of the genes involved and consequently the programmed inhibition of aflatoxin production. Knowledge of the conditions, under which aflatoxin genes are expressed, should contribute to the development of innovative and more cost-effective strategies to

  1. The Inhibitory Effects of Curcuma longa L. Essential Oil and Curcumin on Aspergillus flavus Link Growth and Morphology

    Directory of Open Access Journals (Sweden)

    Flávio Dias Ferreira

    2013-01-01

    Full Text Available The essential oil from Curcuma longa L. was analysed by GC/MS. The major components of the oil were ar-turmerone (33.2%, α-turmerone (23.5% and β-turmerone (22.7%. The antifungal activities of the oil were studied with regard to Aspergillus flavus growth inhibition and altered morphology, as preliminary studies indicated that the essential oil from C. longa inhibited Aspergillus flavus Link aflatoxin production. The concentration of essential oil in the culture media ranged from 0.01% to 5.0% v/v, and the concentration of curcumin was 0.01–0.5% v/v. The effects on sporulation, spore viability, and fungal morphology were determined. The essential oil exhibited stronger antifungal activity than curcumin on A. flavus. The essential oil reduced the fungal growth in a concentration-dependent manner. A. flavus growth rate was reduced by C. longa essential oil at 0.10%, and this inhibition effect was more efficient in concentrations above 0.50%. Germination and sporulation were 100% inhibited in 0.5% oil. Scanning electron microscopy (SEM of A. flavus exposed to oil showed damage to hyphae membranes and conidiophores. Because the fungus is a plant pathogen and aflatoxin producer, C. longa essential oil may be used in the management of host plants.

  2. Modification of the radiation resistance of Aspergillus flavus mycelial units by some chemicals

    International Nuclear Information System (INIS)

    Survival curves for the mycelium of Aspergillus flavus Link var. columnaris Raper and Fennell were constructed after irradiation with gamma rays in the presence of NaCl, NaBr, NaI, KCl, KBr, KI, CaCl2, CaBr2, CaI2, Ca(NO3)2, NaNO2, NaNO3, KNO2, iodoacetic acid, iodoacetamide and vitamin K5. In addition iodized salt was also tested. All the chemicals tested exhibited initial toxicity at zero dose. However, most of the chemicals demonstrated a synergism when present during irradiation. Compounds containing iodine were invariably the strongest radiosensitizers. The iodine present as an admixture in salt also retained its radiosensitizing character. Sodium bromide and calcium bromide behaved in a different way. The initial toxicity was reduced along with an increase in radiation dose resulting in more survival. (orig.)

  3. Bioregulation of aflatoxin biosynthesis by unirradiated and irradiated conidia of Aspergillus flavus

    International Nuclear Information System (INIS)

    A sequential technique involving the transfer of mycelia from peptone-based, aflatoxin-non-supporting medium to glucose based, aflatoxin-supporting medium was used to study the effect of γ-irradiation on the regulation of aflatoxin biosynthesis by Aspergillus flavus. Analysis indicated that irradiation at a dose of 1.00 kGy produced enhancement of aflatoxin biosynthesis in peptone-glucose mineral salt cultures with an increase of adenine nucleotide levels and fatty acid patterns of microsomes and mitochondria. The results suggest that aflatoxin synthesis is not regulated by the overall energy status of the fungal cell but that lipoperoxidation by γ-irradiation plays a role in aflatoxin biosynthesis

  4. Extracellular biosynthesis and characterization of silver nanoparticles using Aspergillus flavus NJP08: A mechanism perspective

    Science.gov (United States)

    Jain, Navin; Bhargava, Arpit; Majumdar, Sonali; Tarafdar, J. C.; Panwar, Jitendra

    2011-02-01

    The present study demonstrates an eco-friendly and low cost protocol for synthesis of silver nanoparticles using the cell-free filtrate of Aspergillus flavus NJP08 when supplied with aqueous silver (Ag+) ions. Identification of the fungal isolate was based on nuclear ribosomal DNA internal transcribed spacer (ITS) identities. Transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) revealed the formation of spherical metallic silver nanoparticles. The average particle size calculated using Dynamic Light Scattering measurements (DLS) was found to be 17 +/- 5.9 nm. UV-Visible and Fourier transform infrared (FTIR) spectroscopy confirmed the presence of extracellular proteins. SDS-PAGE profiles of the extracellular proteins showed the presence of two intense bands of 32 and 35 kDa, responsible for the synthesis and stability of silver nanoparticles, respectively. A probable mechanism behind the biosynthesis is discussed, which leads to the possibility of using the present protocol in future ``nano-factories''.

  5. INHIBITION OF AFLATOXIN PRODUTION BY ASPERGILLUS FLAVUS USING LOW LEVEL Y - IRRADIATION

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    F

    1981-05-01

    Full Text Available Effects o f s e l ected l ow l evel doses of y - Rad iation (100-400 K rad on t he abi l ity o f toxin strain o f Asperg i l l us flavus t o survive and pr oduce a f latox in in c ul t ure med ium and p is tachio nuts hav e been s tudied . A reduction of 60 per c e nt in growth and spore production by Asperg i l l us flavus in c u l ture me di um was observed after treatment wi th 100 K rad of y - Radiation ."nIn spore inoculated pistachio nuts , 100 K rad o f y Radi a tion reduced the a f la toxin B l and G l nroduction by 75% aft er e i ght week s s t orage per iod . The afla toxin prod~ ction ability by Aspergillus f lavus on pistachio nuts was affectively eliminated by t he treatment o f spore inoculated pist achio nuts wi th 200 K rad of y-Radiation , although very l itt le growth coul d be detected after eight weeks ' storage of 40 0 K rad y-irradiated pistachio nuts.  

  6. The Metabolic Responses of Aspergillus flavus to N-Acetylcysteine, Ascorbate, and H2O2

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Aflatoxin, the secondary metabolite of Aspergillus flavus and A. Parasiticus, is the most toxic product in nature. In this study, N-acetylcysteine (NAC), ascorbate, and H2O2 were used to ascertain their effects on fungal metabolic esponse of A. Flavus. The results demonstrated that NAC did not affect fungal growth, but inhibited the aflatoxin B1 production, with the concomitant sporulation reduction. NAC increased the ratio of reduced glutathione (GSH) and oxidized glutathione (GSSG), hut decreased the activity of glutathione reductase (GR). Ascorbate had similar effect on fungal growth, sporulation,and GR activity, but GSH/GSSG and total glutathione (tGSH, including GSH and GSSG) were significantly increased. H2O2 at high concentration (5 mM) inhibited fungal growth, but the aflatoxin production was increased. At the same time, it reduced GR activity and enhanced tGSH. Though reductive agents had different effects on GSH metabolism, reductive conditions inhibited aflatoxin production and sporulation without any effect on fungal growth. The results in this report confirmed that the relationship between oxidative stress and aflatoxin production is theoretically important in controlling aflatoxin contamination.

  7. Inactivation of Aspergillus flavus spores in a sealed package by cold plasma streamers

    Science.gov (United States)

    Sohbatzadeh, F.; Mirzanejhad, S.; Shokri, H.; Nikpour, M.

    2016-01-01

    The main objective of this study is to investigate the inactivation efficacy of cold streamers in a sealed package on pathogenic fungi Aspergillus flavus (A. flavus) spores that artificially contaminated pistachio surface. To produce penetrating cold streamers, electric power supply was adapted to deposit adequate power into the package. The plasma streamers were generated by an alternating high voltage with carrier frequency of 12.5 kHz which was suppressed by a modulated pulsed signal at frequency of 110 Hz. The plasma exposition time was varied from 8 to 18 min to show the effect of the plasma treatment on fungal clearance while the electrode and sample remained at room temperature. This proved a positive effect of the cold streamers treatment on fungal clearance. Benefits of deactivation of fungal spores by streamers inside the package include no heating, short treatment time and adaptability to existing processes. Given its ability to ensure the safety and longevity of food products, this technology has great potential for utilization in food packaging and processing industry. In this study, moisture and pH changes of pistachio samples after plasma streamers treatment were also investigated.

  8. Aspergillus flavus infection induces transcriptional and physical changes in developing maize kernels

    Directory of Open Access Journals (Sweden)

    Andrea L Dolezal

    2014-07-01

    Full Text Available Maize kernels are susceptible to infection by the opportunistic pathogen Aspergillus flavus. Infection results in reduction of grain quality and contamination of kernels with the highly carcinogenic mycotoxin, aflatoxin. To understanding host response to infection by the fungus, transcription of approximately 9,000 maize genes were monitored during the host-pathogen interaction with a custom designed Affymetrix GeneChip® DNA array. More than 1,000 maize genes were found differentially expressed at a fold change of 2 or greater. This included the up regulation of defense related genes and signaling pathways. Transcriptional changes also were observed in primary metabolism genes. Starch biosynthetic genes were down regulated during infection, while genes encoding maize hydrolytic enzymes, presumably involved in the degradation of host reserves, were up regulated. These data indicate that infection of the maize kernel by A. flavus induced metabolic changes in the kernel, including the production of a defense response, as well as a disruption in kernel development.

  9. Inactivation of Aspergillus flavus spores in a sealed package by cold plasma streamers

    Science.gov (United States)

    Sohbatzadeh, F.; Mirzanejhad, S.; Shokri, H.; Nikpour, M.

    2016-06-01

    The main objective of this study is to investigate the inactivation efficacy of cold streamers in a sealed package on pathogenic fungi Aspergillus flavus ( A. flavus) spores that artificially contaminated pistachio surface. To produce penetrating cold streamers, electric power supply was adapted to deposit adequate power into the package. The plasma streamers were generated by an alternating high voltage with carrier frequency of 12.5 kHz which was suppressed by a modulated pulsed signal at frequency of 110 Hz. The plasma exposition time was varied from 8 to 18 min to show the effect of the plasma treatment on fungal clearance while the electrode and sample remained at room temperature. This proved a positive effect of the cold streamers treatment on fungal clearance. Benefits of deactivation of fungal spores by streamers inside the package include no heating, short treatment time and adaptability to existing processes. Given its ability to ensure the safety and longevity of food products, this technology has great potential for utilization in food packaging and processing industry. In this study, moisture and pH changes of pistachio samples after plasma streamers treatment were also investigated.

  10. BIOCONTROL OF ASPERGILLUS FLAVUS AND AFLATOXIN B1 PRODUCTION IN CORN

    Directory of Open Access Journals (Sweden)

    A. Khanafari, H. Soudi, M. Miraboulfathi

    2007-07-01

    Full Text Available The potent mycotoxin aflatoxin B1 is a secondary metabolite of Aspergillus fungi that grow, on a variety of food and feed commodities at any stage during growth, harvest, storage and transportation. The occurrence of aflatoxin contamination is global, with severe problems especially prevalent in developing countries. In present study, corn samples were contaminated with aflatoxin B1 in the concentration of 240 µg/kg. Four trials were inoculated by Lactobacillus plantarum (PTCC 1058. Three control assays were analysed in the same conditions. All the assays were kneaded and incubated for 4-7 days at 37°C. Aflatoxin B1 was determined after extraction by HPLC. Results showed a drastic removal of the mycotoxin with a reduction of 77 % for Aflatoxin B1 by Lactobacillus plantarum. In the Inoculated corns, spore germination of A. flavus was totally inhibited. Results in inoculated spikes showed a high percentage of reduction of aflatoxin after incubation by Lb. plantarum. Gram staining of a sample from inoculated corns and microscopic observation demonstrated that the growth of A. flavus spores was totally inhibited by Lb. plantarum. Fungal spores were surrounded by Lactobacillus plantarum and spores were degraded.

  11. ASSESSMENT OF GENETIC DIVERSITY BASED ON POLYPEPTIDE BANDING PATTERN AMONG DIFFERENT ISOLATES OF ASPERGILLUS FLAVUS USING SDS-PAGE

    OpenAIRE

    2013-01-01

    A quantitative categorization of total storage proteins profile of 6 isolates of Aspergillus flavus was performed by sodium dodecyl sulphate- polyacrylamide gel electrophoresis (SDS-PAGE). This technique was used to explore the level of genetic discrepancy in A.  flavus isolates. Total soluble proteins were resolved on 10% resolving gel. A total of 27 polypeptide bands were obtained among which 20 bands were present in all isolates but other 7 bands of molecular weight (127.38, 110.14, 109.74...

  12. A Novel Y319H Substitution in CYP51C Associated with Azole Resistance in Aspergillus flavus

    OpenAIRE

    Paul, R. A.; Rudramurthy, S. M.; Meis, J F; Mouton, J. W.; Chakrabarti, A

    2015-01-01

    This study aimed to explore any mutation in the CYP51 gene conferring azole resistance in Aspergillus flavus. Two voriconazole-resistant and 45 voriconazole-susceptible isolates were included in the study. Sequence analysis demonstrated a T1025C nucleotide change in CYP51C, resulting in the Y319H amino acid substitution in one resistant isolate. However, the earlier described T788G mutation in CYP51C conferring voriconazole resistance in A. flavus isolates was present in all isolates, irrespe...

  13. A Novel Y319H Substitution in CYP51C Associated with Azole Resistance in Aspergillus flavus.

    Science.gov (United States)

    Paul, R A; Rudramurthy, S M; Meis, J F; Mouton, J W; Chakrabarti, A

    2015-10-01

    This study aimed to explore any mutation in the CYP51 gene conferring azole resistance in Aspergillus flavus. Two voriconazole-resistant and 45 voriconazole-susceptible isolates were included in the study. Sequence analysis demonstrated a T1025C nucleotide change in CYP51C, resulting in the Y319H amino acid substitution in one resistant isolate. However, the earlier described T788G mutation in CYP51C conferring voriconazole resistance in A. flavus isolates was present in all isolates, irrespective of their susceptibility status. PMID:26248359

  14. Amy1, the alpha-Amylase Gene of Aspergillus flavus: Involvement in Aflatoxin Biosynthesis in Maize Kernels.

    Science.gov (United States)

    Fakhoury, A M; Woloshuk, C P

    1999-10-01

    ABSTRACT Aspergillus flavus is the causal agent of an ear and kernel rot in maize. In this study, we characterized an alpha-amylase-deficient mutant and assessed its ability to infect and produce aflatoxin in wounded maize kernels. The alpha-amylase gene Amy1 was isolated from A. flavus, and its DNA sequence was determined to be nearly identical to Amy3 of A. oryzae. When Amy1 was disrupted in an aflatoxigenic strain of A. flavus, the mutant failed to produce extracellular alpha-amylase and grew 45% the rate of the wild-type strain on starch medium. The mutant produced aflatoxin in medium containing glucose but not in a medium containing starch. The alpha-amylase-deficient mutant produced aflatoxin in maize kernels with wounded embryos and occasionally produced aflatoxin only in embryos of kernels with wounded endosperm. The mutant strain failed to produce aflatoxin when inoculated onto degermed kernels. In contrast, the wild-type strain produced aflatoxin in both the endosperm and embryo. These results suggest that alpha-amylase facilitates aflatoxin production and growth of A. flavus from a wound in the endosperm to the embryo. A 14-kDa trypsin inhibitor associated with resistance to A. flavus and aflatoxin in maize also inhibited the alpha-amylase from A. flavus, indicating that it is a bifunctional inhibitor. The inhibitor may have a role in resistance, limiting the growth of the fungus in the endosperm tissue by inhibiting the degradation of starch. PMID:18944734

  15. APPLICATION OF ULTRASOUND TO CONTROL OF ASPERGILLUS FLAVUS IN COSMETICS = APLICAÇÃO DE ULTRASSOM NO CONTROLE DE ASPERGILLUS FLAVUS EM COSMÉTICOS

    Directory of Open Access Journals (Sweden)

    Kassima Timoni Góes-Campanha

    2011-01-01

    Full Text Available The effect of ultrasound on organic compounds in living tissue and are often related to the cavitation’ phenomenon, a term used to describe the formation of cavities or bubbles in a liquid medium containing varying amounts of gas or vapor that are dissolved in the middle. In medicine it is suggested that ultrasound of high intensity is able to cause some reduction in certain infectious agents and microbiology, mechanisms of inactivation of cells appear to be associated with cavitation. Due to the high power of fungal contamination of cosmetics, it is important to develop new techniques to preserve it to rapid fungi deterioration and subsequent consumer health hazard. On the present work it was probed the efficiency of ultrasound in decreasing the growth of Aspergillus flavus in cosmetic.Thus contaminated samples with the above mentioned fungus, were irradiated at constant temperature (25 oC and power (600W/cm2, for a variety of time exposure: 0 (control, 12, 16, and 20 minutes. The ultrasound generator model VCX- 600 was utilized.It was possible to show that the use of ultrasound is efficient in decreasing the growth of microrganisms and thus preserve cosmetic which went from 35,000 CFU/mL to 50 CFU/mL. Ultrasound is a excellent biocide agent in preparation and preservation of emulsion-type cosmetics. Twenty minutes of continuous irradiation yelded an almost complete depletion of microrganisms. = Devido ao alto poder de contaminação dos cosméticos por fungos, é de grande importância o desenvolvimento de novas técnicas para preservação desses, uma vez que a contaminação microbiológica pode, além de causar a deterioração do produto, apresentar danos à saúde do consumidor. Procurou-se, então, nesse trabalho, determinar a eficácia do ultrassom na diminuição do crescimento do fungo Aspergillus flavus em cosméticos. Para isso, amostras de cosméticos contaminados com o fungo foram irradiadas em equipamento gerador de ultrassom

  16. Assessment of the antifungal activity of Spirulina platensis phenolic extract against Aspergillus flavus Avaliação da atividade antifúngica de extrato fenólico de Spirulina platensis contra Aspergillus flavus

    OpenAIRE

    Michele Moraes de Souza; Luciana Prietto; Anelise Christ Ribeiro; Taiana Denardi de Souza; Eliana Badiale-Furlong

    2011-01-01

    The production of safe food has stimulated the search for natural substances that possess antifungal activity. The indirect methods of estimating fungal biomass are based on the measurement of glucosamine, ergosterol and protein - typical compounds produced during the development of biomass. The aim of the study was to assess the effect of the phenolic extract from Spirulina platensis on the production of structural compounds in Aspergillus flavus, in order to identify its action on fungal in...

  17. Assessment of the antifungal activity of Spirulina platensis phenolic extract against Aspergillus flavus Avaliação da atividade antifúngica de extrato fenólico de Spirulina platensis contra Aspergillus flavus

    Directory of Open Access Journals (Sweden)

    Michele Moraes de Souza

    2011-12-01

    Full Text Available The production of safe food has stimulated the search for natural substances that possess antifungal activity. The indirect methods of estimating fungal biomass are based on the measurement of glucosamine, ergosterol and protein - typical compounds produced during the development of biomass. The aim of the study was to assess the effect of the phenolic extract from Spirulina platensis on the production of structural compounds in Aspergillus flavus, in order to identify its action on fungal inhibition. The Spirulina platensis methanolic extracts presented 1.15 mg phenolic compound/g Spirulina platensis, which showed an antifungal effect against Aspergillus flavus, inhibiting the glucosamine production up to 56%. Therefore, it may be employed as natural defense when food protection is necessary.A produção de alimentos seguros tem estimulado a busca por substâncias naturais que possuem atividade antifúngica. Os métodos indiretos de estimativa de biomassa fúngica são baseados na medição de glucosamina, ergosterol e proteína - compostos típicos produzidos durante o desenvolvimento da biomassa. Neste estudo, objetivou-se avaliar o efeito do extrato fenólico de Spirulina platensis na produção de componentes estruturais em Aspergillus flavus, a fim de identificar seu mecanismo de ação dos fenóis na inibição fúngica. O extrato metanólico de Spirulina platensis apresentou 1,15 mg de compostos fenólicos/g Spirulina platensis, apresentando um efeito antifúngico contra Aspergillus flavus, inibindo a produção de glucosamina em até 56%. Portanto, pode ser empregado como antifúngico natural quando for necessária a proteção de alimentos.

  18. A volatile relationship: profiling an inter-kingdom dialogue between two plant pathogens, Ralstonia Solanacearum and Aspergillus Flavus.

    Science.gov (United States)

    Spraker, Joseph E; Jewell, Kelsea; Roze, Ludmila V; Scherf, Jacob; Ndagano, Dora; Beaudry, Randolph; Linz, John E; Allen, Caitilyn; Keller, Nancy P

    2014-05-01

    Microbes in the rhizosphere have a suite of extracellular compounds, both primary and secondary, that communicate with other organisms in their immediate environment. Here, we describe a two-way volatile interaction between two widespread and economically important soil-borne pathogens of peanut, Aspergillus flavus and Ralstonia solanacearum, a fungus and bacterium, respectively. In response to A. flavus volatiles, R. solanacearum reduced production of the major virulence factor extracellular polysaccharide (EPS). In parallel, A. flavus responded to R. solanacearum volatiles by reducing conidia production, both on plates and on peanut seeds and by increasing aflatoxin production on peanut. Volatile profiling of these organisms using solid-phase micro-extraction gas chromatography mass spectroscopy (SPME-GCMS) provided a first glimpse at the compounds that may drive these interactions. PMID:24801606

  19. Genome-wide analysis of the Zn(II)₂Cys₆ zinc cluster-encoding gene family in Aspergillus flavus.

    Science.gov (United States)

    Chang, Perng-Kuang; Ehrlich, Kenneth C

    2013-05-01

    Proteins with a Zn(II)₂Cys₆ domain, Cys-X₂-Cys-X₆-Cys-X₅₋₁₂-Cys-X₂-Cys-X₆₋₉-Cys (hereafter, referred to as the C6 domain), form a subclass of zinc finger proteins found exclusively in fungi and yeast. Genome sequence databases of Saccharomyces cerevisiae and Candida albicans have provided an overview of this family of genes. Annotation of this gene family in most fungal genomes is still far from perfect and refined bioinformatic algorithms are urgently needed. Aspergillus flavus is a saprophytic soil fungus that can produce the carcinogenic aflatoxin. It is the second leading causative agent of invasive aspergillosis. The 37-Mb genome of A. flavus is predicted to encode 12,000 proteins. Two and a half percent of the total proteins are estimated to contain the C6 domain, more than twofold greater than those estimated for yeast, which is about 1 %. The variability in the spacing between cysteines, C₃-C₄ and C₅-C₆, in the zinc cluster enables classification of the domains into distinct subgroups, which are also well conserved in Aspergillus nidulans. Sixty-six percent (202/306) of the A. flavus C6 proteins contain a specific transcription factor domain, and 7 % contain a domain of unknown function, DUF3468. Two A. nidulans C6 proteins containing the DUF3468 are involved in asexual conidiation and another two in sexual differentiation. In the anamorphic A. flavus, a homolog of the latter lacks the C6 domain. A. flavus being heterothallic and reproducing mainly through conidiation appears to have lost some components involved in homothallic sexual development. Of the 55 predicted gene clusters thought to be involved in production of secondary metabolites, only about half have a C6-encoding gene in or near the gene clusters. The features revealed by the A. flavus C6 proteins likely are common for other ascomycete fungi. PMID:23563886

  20. Resistance to Aspergillus flavus in maize and peanut:Molecular biology, breeding, environmental stress,and future perspectives

    Institute of Scientific and Technical Information of China (English)

    Jake; C.Fountain; Pawan; Khera; Liming; Yang; Spurthi; N.Nayak; Brian; T.Scully; Robert; D.Lee; Zhi-Yuan; Chen; Robert; C.Kemerait; Rajeev; K.Varshney; Baozhu; Guo

    2015-01-01

    The colonization of maize(Zea mays L.) and peanut(Arachis hypogaea L.) by the fungal pathogen Aspergillus flavus results in the contamination of kernels with carcinogenic mycotoxins known as aflatoxins leading to economic losses and potential health threats to humans. The regulation of aflatoxin biosynthesis in various Aspergillus spp. has been extensively studied, and has been shown to be related to oxidative stress responses. Given that environmental stresses such as drought and heat stress result in the accumulation of reactive oxygen species(ROS) within host plant tissues, host-derived ROS may play an important role in cross-kingdom communication between host plants and A. flavus. Recent technological advances in plant breeding have provided the tools necessary to study and apply knowledge derived from metabolomic, proteomic, and transcriptomic studies in the context of productive breeding populations. Here, we review the current understanding of the potential roles of environmental stress, ROS, and aflatoxin in the interaction between A.flavus and its host plants, and the current status in molecular breeding and marker discovery for resistance to A. flavus colonization and aflatoxin contamination in maize and peanut. We will also propose future directions and a working model for continuing research efforts linking environmental stress tolerance and aflatoxin contamination resistance in maize and peanut.

  1. Resistance to Aspergillus flavus in maize and peanut:Molecular biology, breeding, environmental stress, and future perspectives

    Institute of Scientific and Technical Information of China (English)

    Jake C. Fountain; Baozhu Guo; Pawan Khera; Liming Yang; Spurthi N. Nayak; Brian T. Scully; Robert D. Lee; Zhi-Yuan Chen; Robert C. Kemerait; Rajeev K. Varshney

    2015-01-01

    The colonization of maize (Zea mays L.) and peanut (Arachis hypogaea L.) by the fungal pathogen Aspergillus flavus results in the contamination of kernels with carcinogenic mycotoxins known as aflatoxins leading to economic losses and potential health threats to humans. The regulation of aflatoxin biosynthesis in various Aspergillus spp. has been extensively studied, and has been shown to be related to oxidative stress responses. Given that environmental stresses such as drought and heat stress result in the accumulation of reactive oxygen species (ROS) within host plant tissues, host-derived ROS may play an important role in cross-kingdom communication between host plants and A. flavus. Recent technological advances in plant breeding have provided the tools necessary to study and apply knowledge derived from metabolomic, proteomic, and transcriptomic studies in the context of productive breeding populations. Here, we review the current understanding of the potential roles of environmental stress, ROS, and aflatoxin in the interaction between A. flavus and its host plants, and the current status in molecular breeding and marker discovery for resistance to A. flavus colonization and aflatoxin contamination in maize and peanut. We will also propose future directions and a working model for continuing research efforts linking environmental stress tolerance and aflatoxin contamination resistance in maize and peanut.

  2. POTENTIAL OF ESSENTIAL OILS FOR PROTECTION OF GRAINS CONTAMINATED BY AFLATOXIN PRODUCED BY Aspergillus flavus

    Directory of Open Access Journals (Sweden)

    EdlayneGonçalez

    2014-06-01

    Full Text Available Aflatoxin B1 (AFB1 is a highly toxic and carcinogenic metabolite produced by Aspergillus species on food and agricultural commodities. Inhibitory effects of essential oils of Ageratum conyzoides (mentrasto and Origanum vulgare (oregano on the mycelial growth and aflatoxin B1 production by Aspergillus flavus have been studied previously in culture medium. The aim of this study was to evaluate aflatoxin B1 production by Aspergillus flavus in real food systems (corn and soybean treated with Ageratum conyzoides (mentrasto and Origanum vulgare (oregano essential oils. Samples with 60 g of the grains were treated with different volumes of essential oils, 200, 100, 50, and 10 μL for oregano and 50, 30, 15, and 10μL for mentrasto. Fungal growth was evaluated by disk diffusion method. Aflatoxin B1 production was evaluated inoculating suspensions of A. flavus containing 1.3×105 spores/ mL in 60 g of grains (corn and soybeans after adjusting the water activity at 0.94. Aflatoxin was quantified by photodensitometry. Fungal growth and aflatoxin production were inhibited by essential oils, but the mentrasto oil was more effective in soybeans than that of oregano. On the other hand, in corn samples, the oregano essential oil was more effective than that of mentrasto. Chemical compositions of the essential oils were also investigated. The GC/MS oils analysis showed that the main component of mentrasto essential oil is precocene I and of the main component of oregano essential oil is 4-terpineol. The results indicate that both essential oils can become an alternative for the control of aflatoxins in corn and soybeans.

  3. Control of Aspergillus flavus Growth in Tomato Paste by Cinnamomum zeylanicum and Origanum vulgare L. Essential Oils

    OpenAIRE

    F Kalantary

    2014-01-01

    This study was conducted to evaluate the antifungal activities of cinnamon (Cinnamomum zeylanicum) and oregano (Origanum vulgare L.) essential oils against Aspergillus flavus in culture media and tomato paste. The chemical compositions of the essential oils were determined by Gas Chromatography-Mass Spectroscopy (GC-MS). Trans- cinnamaldehyde was found to be the main constituent of Cinnamomum zeylanicum essential oil (CZEO), followed by methyl eugenol, δ- cadinene and γ- cadinene. The major c...

  4. Environmental factors modify carbon nutritional patterns and niche overlap between Aspergillus flavus and Fusarium verticillioides strains from maize.

    OpenAIRE

    Giorni, Paola; Magan, Naresh; Battilani, Paola

    2009-01-01

    This study examined the utilization patterns of key carbon sources (CS, 24: including key sugars, amino acids and fatty acids) in maize by strains of Aspergillus flavus and Fusarium verticillioides under different water activity (aw, 0.87–0.98 aw) and temperature (20–35 °C) values and compared the niche overlap indices (NOI) that estimate the in vitro CS utilization profiles [Wilson, M., Lindow, S.E., 1994. Coexistence among epiphytic bacterial populations mediated through nutritional resourc...

  5. Antifungal Activity of Kebar Grass Leaf Extracts on the Growth of Aflatoxigenic Aspergillus flavus in Food Model Media

    OpenAIRE

    Meike Meilan Lisangan; Rizal Syarief 1; Winiati P. Rahayu3); OKKY S. DHARMAPUTRA

    2014-01-01

    Some fungal species are toxigenic, for example Aspergillus flavus which can produce aflatoxin. Various methods have been conducted to reduce aflatoxin contamination in foods, among others using antimicrobial compounds derived from natural plant extract. Kebar grass (Biophytum petersianum Klotszch) is one of herbs that has potency as antimicrobe. The objective of this study was to investigate the effect of three types of model media i.e. carbohydrate- enriched media, fat-enriched media, and pr...

  6. Stimulation by Hyphopichia burtonii and Bacillus amyloliquefaciens of aflatoxin production by Aspergillus flavus in irradiated maize and rice grains

    Energy Technology Data Exchange (ETDEWEB)

    Cuero, R.G.; Smith, J.E.; Lacey, J.

    1987-05-01

    Aspergillus flavus was grown on maize and rice extract agars and on irradiated viable cracked maize and rice grains, either in pure culture or in dual culture with wild strains of either Hyphopichia burtonii or Bacillus amyloliquefaciens. Aflatoxin production by A. flavus and its growth and interactions with the other microorganisms were studied at three water activities (a/sub w/) (0.98, 0.95, and 0.90) and two temperatures (25 and 16/sup 0/C). Both H. burtonii and B. amyloliquefaciens markedly stimulated growth and aflotoxin production by A. flavus on cracked maize, especially at 25/sup 0/C and 0.95 and 0.98 a/sub w/. No aflatoxin was detected in pure cultures of A. flavus on cracked rice after 12 days of incubation at 25/sup 0/C, but some was produced by mixed cultures at 16/sup 0/C and 0.98 a/sub w/. The morphological interactions among A. flavus, H. burtonii, and B. amyloliquefaciens were also examined on maize and rice extract agars under similar controlled conditions.

  7. Stimulation by Hyphopichia burtonii and Bacillus amyloliquefaciens of aflatoxin production by Aspergillus flavus in irradiated maize and rice grains

    International Nuclear Information System (INIS)

    Aspergillus flavus was grown on maize and rice extract agars and on irradiated viable cracked maize and rice grains, either in pure culture or in dual culture with wild strains of either Hyphopichia burtonii or Bacillus amyloliquefaciens. Aflatoxin production by A. flavus and its growth and interactions with the other microorganisms were studied at three water activities (a/sub w/) (0.98, 0.95, and 0.90) and two temperatures (25 and 160C). Both H. burtonii and B. amyloliquefaciens markedly stimulated growth and aflotoxin production by A. flavus on cracked maize, especially at 250C and 0.95 and 0.98 a/sub w/. No aflatoxin was detected in pure cultures of A. flavus on cracked rice after 12 days of incubation at 250C, but some was produced by mixed cultures at 160C and 0.98 a/sub w/. The morphological interactions among A. flavus, H. burtonii, and B. amyloliquefaciens were also examined on maize and rice extract agars under similar controlled conditions

  8. Characterization of Expressed Sequence Tag-Derived Simple Sequence Repeat Markers for Aspergillus flavus: Emphasis on Variability of Isolates from the Southern United States

    Science.gov (United States)

    Simple Sequence Repeat (SSR) markers were developed from Aspergillus flavus expressed sequence tag (EST) database to conduct an analysis of genetic relationships of Aspergillus isolates from numerous host species and geographical regions, but primarily from the United States. Twenty-nine primers wer...

  9. Tissue-specific gene expression in maize seeds during colonization by Aspergillus flavus and Fusarium verticillioides.

    Science.gov (United States)

    Shu, Xiaomei; Livingston, David P; Franks, Robert G; Boston, Rebecca S; Woloshuk, Charles P; Payne, Gary A

    2015-09-01

    Aspergillus flavus and Fusarium verticillioides are fungal pathogens that colonize maize kernels and produce the harmful mycotoxins aflatoxin and fumonisin, respectively. Management practice based on potential host resistance to reduce contamination by these mycotoxins has proven difficult, resulting in the need for a better understanding of the infection process by these fungi and the response of maize seeds to infection. In this study, we followed the colonization of seeds by histological methods and the transcriptional changes of two maize defence-related genes in specific seed tissues by RNA in situ hybridization. Maize kernels were inoculated with either A. flavus or F. verticillioides 21-22 days after pollination, and harvested at 4, 12, 24, 48, 72, 96 and 120 h post-inoculation. The fungi colonized all tissues of maize seed, but differed in their interactions with aleurone and germ tissues. RNA in situ hybridization showed the induction of the maize pathogenesis-related protein, maize seed (PRms) gene in the aleurone and scutellum on infection by either fungus. Transcripts of the maize sucrose synthase-encoding gene, shrunken-1 (Sh1), were observed in the embryo of non-infected kernels, but were induced on infection by each fungus in the aleurone and scutellum. By comparing histological and RNA in situ hybridization results from adjacent serial sections, we found that the transcripts of these two genes accumulated in tissue prior to the arrival of the advancing pathogens in the seeds. A knowledge of the patterns of colonization and tissue-specific gene expression in response to these fungi will be helpful in the development of resistance. PMID:25469958

  10. Improving Peanut Productivity and Resistance to Aspergillus flavus L Through mutation Induction

    International Nuclear Information System (INIS)

    The present study was conducted to improve peanut productivity and resistance to Aspergillus flavus that caused aflatoxin formation in peanut seeds . To achieve these goals , dry seeds of the two local varieties (Giza 4 and Giza5) were irradiated with gamma ray doses of 0 , 50 , 100 , 150 , 200 , 250 , 300 Gy. The irradiated seeds were sown to get the M1 and M2 generations. Six high yielding mutants were selected in M2 from irradiated populations of 150 Gy and 200 Gy for Giza 4 and Giza 5 respectively. These mutants were evaluated in M3 generation for yield and yield components , quality traits (protein and oil content) and the resistance to Aspergillus flavus infection. The obtained results revealed that analysis of variance for Giza 4 selected mutants showed significant differences between genotypes for different studied characters except for plant height and no. of branches /plant .However, for Giza5 selected mutants, significant differences between genotypes were only obtained for plant height , no of pods/plant, weight of pods/plant, weight of seeds/plant, and weight of 100 seeds. Different M3 mutants that selected from irradiated populations of both two peanut cultivars Giza4 and Giza5 shod marked improvement for yield and yield components, and quality traits in comparison with their mother varieties.The results of M3 progeny test indicated that most selected mutants retained the features of their M2 selectors, suggesting that they were considered true breeding materials. For Giza 4 selected mutants, aflatoxin concentrations ranged from 31.11 μg for mutant 1 to 188.46 μ g for mutant3 in comparison with 42.76 μg for the mother variety Giza 4. The lowest yielding progenies of mutant1 (1 ) showed the lowest aflatoxin concentrations as compared with the mother variety Giza 4 and other mutants, therefore the use of induced mutations for peanut improvement may be led to the development of improved varieties .However, for Giza 5 selected mutants aflatoxin

  11. Reduction of Aflatoxin in Pistachio Through Biological Control of Aspergillus flavus

    Science.gov (United States)

    A retrotransposon, AFLAV (A. flavus retrotransposon), has been recently characterized in A. flavus. Complete DNA sequence of 7784 bp containing the AFLAV has been submitted to GenBank (accession number AY485785). Multicopies of this transposon are dispersed in the chromosomes of A. flavus. PCR pr...

  12. Sexual Reproduction in Aspergillus flavus Sclerotia: Acquisition of Novel Alleles from Soil Populations and Uniparental Mitochondrial Inheritance.

    Directory of Open Access Journals (Sweden)

    Bruce W Horn

    Full Text Available Aspergillus flavus colonizes agricultural commodities worldwide and contaminates them with carcinogenic aflatoxins. The high genetic diversity of A. flavus populations is largely due to sexual reproduction characterized by the formation of ascospore-bearing ascocarps embedded within sclerotia. A. flavus is heterothallic and laboratory crosses between strains of the opposite mating type produce progeny showing genetic recombination. Sclerotia formed in crops are dispersed onto the soil surface at harvest and are predominantly produced by single strains of one mating type. Less commonly, sclerotia may be fertilized during co-infection of crops with sexually compatible strains. In this study, laboratory and field experiments were performed to examine sexual reproduction in single-strain and fertilized sclerotia following exposure of sclerotia to natural fungal populations in soil. Female and male roles and mitochondrial inheritance in A. flavus were also examined through reciprocal crosses between sclerotia and conidia. Single-strain sclerotia produced ascospores on soil and progeny showed biparental inheritance that included novel alleles originating from fertilization by native soil strains. Sclerotia fertilized in the laboratory and applied to soil before ascocarp formation also produced ascospores with evidence of recombination in progeny, but only known parental alleles were detected. In reciprocal crosses, sclerotia and conidia from both strains functioned as female and male, respectively, indicating A. flavus is hermaphroditic, although the degree of fertility depended upon the parental sources of sclerotia and conidia. All progeny showed maternal inheritance of mitochondria from the sclerotia. Compared to A. flavus populations in crops, soil populations would provide a higher likelihood of exposure of sclerotia to sexually compatible strains and a more diverse source of genetic material for outcrossing.

  13. Indole Diterpenoids and Isocoumarin from the Fungus, Aspergillus flavus, Isolated from the Prawn, Penaeus vannamei

    Directory of Open Access Journals (Sweden)

    Kunlai Sun

    2014-06-01

    Full Text Available Two new indole-diterpenoids (1 and 2 and a new isocoumarin (3, along with the known β-aflatrem (4, paspalinine (5, leporin B (6, α-cyclopiazonic acid (7, iso-α-cyclopiazonic acid (8, ditryptophenaline (9, aflatoxin B1 (10, 7-O-acetylkojic acid (11 and kojic acid (12, were isolated from the fermentation broth of the marine-derived fungus, Aspergillus flavus OUCMDZ-2205. The structures of Compounds 1–12 were elucidated by spectroscopic analyses, quantum ECD calculations and the chemical method. New Compound 1 exhibited antibacterial activity against Staphylococcus aureus with a MIC value of 20.5 μM. Both new Compounds 1 and 2 could arrest the A549 cell cycle in the S phase at a concentration of 10 μM. Compound 1 showed PKC-beta inhibition with an IC50 value of 15.6 μM. In addition, the absolute configurations of the known compounds, 4–6 and leporin A (6a, were also determined for the first time.

  14. Determination of the D10 radiation dose of aspergillus flavus spores in dried fig

    International Nuclear Information System (INIS)

    To assess the potential of irradiation processing as a means of controlling the presence of aspergillus flavus in dried fig a toxigenic isolate was used in this study. The spore suspensions (107 spores/ml) and artificially inoculated fig pellets were irradiated in a caesium 137 source at different doses. Survivor plots (log10 number of survivors versus dose) were determined by regression analysis of the data; correlation coefficients>0.98 were obtained for both, decimal reduction doses (D values in kGy) were calculated as the reciprocal of the slope obtained from the regression analysis. The D-values for spores in Tween-80 dilution fluid (0.2% Tween-80, 0.85% sodium chloride) and in dried fig pellets were determined 0.5291 kGy and 0.6823 kGy, respectively. In addition, some chemical analysis and sensory test were made and it was found that irradiation has no adverse effect on quality of dried fig fruits

  15. Effect of climate change on Aspergillus flavus and aflatoxin B1 production

    Directory of Open Access Journals (Sweden)

    Angel eMedina

    2014-07-01

    Full Text Available This review considers the available information on the potential impact of key environmental factors and their interactions on the molecular ecology, growth and aflatoxin production by Aspergillus flavus in vitro and in maize grain. The recent studies which have been carried out to examine the impact of water activity x temperature on aflatoxin biosynthesis and phenotypic aflatoxin production are examined. These have shown that there is a direct relationship between the relative expression of key regulatory and structural genes under different environmental conditions which correlate directly with aflatoxin B1 production. A model has been developed to integrate the relative expression of 10 biosynthetic genes in the pathway, growth and aflatoxin B1 (AFB1 production which was validated under elevated temperature and water stress conditions. The effect of interacting conditions of aw x temperature x elevated CO2 (2x and 3x existing levels are detailed for the first time. This suggests that while such interacting environmental conditions have little effect on growth they do have a significant impact on aflatoxin biosynthetic gene expression (structural aflD and regulatory aflR genes and can significantly stimulate the production of AFB1. While the individual factors alone have an impact, it is the combined effect of these three abiotic factors which have an impact on mycotoxin production. This approach provides data which is necessary to help predict the real impacts of climate change on mycotoxigenic fungi.

  16. Aspergillus flavus-Induced Brain Abscess in an Immunocompetent Child: Case report.

    Science.gov (United States)

    Al-Maskari, Nawal; Hussain, Ibrahim; Jumaa, Suleiman; Al-Shail, Essam A

    2016-05-01

    Intracranial aspergillosis is an extremely rare manifestation of invasive aspergillosis in immunocompetent children and is associated with high morbidity and mortality. We report a 12-year-old immunocompetent male child who was referred to the King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia, in May 2010 after a sudden-onset headache and loss of consciousness. Brain imaging revealed a large right space-occupying occipital lesion and the patient underwent a craniotomy and resection. Histopathology of the lesion revealed necrotising granulomatous fungal encephalitis with many hyphae engulfed by multinucleated giant histiocytes. Two days later, a computed tomography scan showed debulking of the fungal mass and the patient was discharged on oral voriconazole. However, imaging at a six-week follow-up showed progression of the abnormality. A residual or persistent fungal brain lesion was suspected. Further neurosurgical resection of the lesion was performed and cultures showed growth of Aspergillus flavus. The patient was treated successfully with antifungal therapy over the following two years. PMID:27226920

  17. Aspergillus flavus-Induced Brain Abscess in an Immunocompetent Child; Case report

    Directory of Open Access Journals (Sweden)

    Nawal Al-Maskari

    2016-05-01

    Full Text Available Intracranial aspergillosis is an extremely rare manifestation of invasive aspergillosis in immunocompetent children and is associated with high morbidity and mortality. We report a 12-year-old immunocompetent male child who was referred to the King Faisal Specialist Hospital & Research Centre, Riyadh, Saudi Arabia, in May 2010 after a sudden-onset headache and loss of consciousness. Brain imaging revealed a large right space-occupying occipital lesion and the patient underwent a craniotomy and resection. Histopathology of the lesion revealed necrotising granulomatous fungal encephalitis with many hyphae engulfed by multinucleated giant histiocytes. Two days later, a computed tomography scan showed debulking of the fungal mass and the patient was discharged on oral voriconazole. However, imaging at a six-week follow-up showed progression of the abnormality. A residual or persistent fungal brain lesion was suspected. Further neurosurgical resection of the lesion was performed and cultures showed growth of Aspergillus flavus. The patient was treated successfully with antifungal therapy over the following two years.

  18. Biosynthesis of silver nanoparticles synthesized by Aspergillus flavus and their antioxidant, antimicrobial and cytotoxicity properties

    Indian Academy of Sciences (India)

    Ghassan M Sulaiman; Hiba T Hussien; Maysoon M N M Saleem

    2015-06-01

    In the present study, biosynthesis of silver nanoparticles and its antioxidant, antimicrobial and cytotoxic activities were investigated. Silver nanoparticles were extracellularly synthesized using Aspergillus flavus and the formation of nanoparticles was observed after 72 h of incubation. The results recorded from colour changes, UV–vis spectrum and X-ray diffraction (XRD) support the biosynthesis and characterization of silver nanoparticles. UV–vis spectral analysis showed silver surface plasmon resonance band at 420 nm. X-ray diffraction showed that the particles were crystalline with face-centred cubic structure at 45.05°, 65.45° and 78.65° and the size of the silver nanoparticles was 33.5 nm. The synthesized silver nanoparticles showed potent antimicrobial activity against various pathogens, including bacteria and fungi. Biosynthesized silver nanoparticles exhibited strong antioxidant activity as well as cytotoxicity against HL-60 cells in a dose–response relationship. The powerful bioactivity demonstrated by the synthesized silver nanoparticles leads towards the biomedical use as antioxidant, antibacterial and cytotoxic agents.

  19. 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.

  20. Toward elucidation of genetic and functional genetic mechanisms in corn host resistance to Aspergillus flavus infection and aflatoxin contamination

    Directory of Open Access Journals (Sweden)

    Xueyan eShan

    2014-07-01

    Full Text Available Aflatoxins are carcinogenic mycotoxins produced by some species in the Aspergillus genus, such as A. flavus and A. parasiticus. Contamination of aflatoxins in corn profusely happens at pre-harvest stage when heat and drought field conditions favor A. flavus colonization. Commercial corn hybrids are generally susceptible to A. flavus infection. An ideal strategy for preventing aflatoxin contamination is through the enhancement of corn host resistance to Aspergillus infection and aflatoxin production. Constant efforts have been made by corn breeders to develop resistant corn genotypes. Significantly low levels of aflatoxin accumulation have been determined in certain resistant corn inbred lines. A number of reports of quantitative trait loci (QTLs have provided compelling evidence supporting the quantitative trait genetic basis of corn host resistance to aflatoxin accumulation. Important findings have also been obtained from the investigation on candidate resistance genes through transcriptomics approach. Elucidation of molecular mechanisms will provide in-depth understanding of the host-pathogen interactions and hence facilitate the breeding of corn with resistance to A. falvus infection and aflatoxin accumulation.

  1. Effect of Plectranthus glandulosus and Ocimum gratissimum Essential Oils on Growth of Aspergillus flavus and Aflatoxin B1 Production

    Directory of Open Access Journals (Sweden)

    Mbofung, CMF.

    2008-01-01

    Full Text Available Essential oils of Ocimum gratissimum and Plectranthus glandulosus leaves were extracted by steam distillation and analysed by GC-MS, and their effects on growth and aflatoxin B1 production by Aspergillus flavus were tested at five levels (i.e 200, 400, 600, 800 and 1000 mg/l using SMKY agar medium. The main components of O. gratissimum were thymol (47.7% and -terpinene (14.3% whereas those of P. glandulosus were represented by -terpinene (30.8% and terpinolene (25.2%. After 8 days of incubation on essential oil-supplemented medium, growth of A. flavus was totally inhibited by 800 mg/l of O. gratissimum essential oil and by 1000 mg/l of P. glandulosus essential oil. The effect of essential oils on aflatoxin B1 synthesis was evaluated in SMKY broth. The medium supplemented with different essential oil concentrations, was inoculated with A. flavus mycelium and incubated at 25 °C. At 2, 4, 6 and 8 days, aflatoxin B1 concentrations in the supernatant were estimated using Enzyme Linked Immuno-Sorbent Assay (ELISA. Results showed that aflatoxin B1 synthesis was inhibited by 1000 mg/l of both essential oils of O. gratissimum and P. glandulosus after 8 days of incubation. Results obtained in the present study indicate the possibility of exploiting O. gratissimum and P. glandulosus essential oils in the fight against strains of A. flavus responsible for biodeterioration of stored food products.

  2. Production of aflatoxins by Aspergillus flavus and of fumonisins by Fusarium species isolated from Brazilian sorghum Avaliação da toxigenidade das cepas de Aspergillus flavus e Fusarium spp. isoladas de amostras de sorgo

    Directory of Open Access Journals (Sweden)

    Josefa B. da Silva

    2004-09-01

    Full Text Available Fifty-nine Aspergillus flavus and 35 Fusarium verticillioides strains, isolated from freshly harvested (10 and stored (130 Brazilian sorghum samples, were tested regarding their ability to produce aflatoxins (coconut milk agar and fumonisins (rice culture, respectively. Aflatoxins B1 and B2 were detected by TLC, and fumonisins B1 and B2 were analyzed by HPLC. Thirty-eight (64.4% A. flavus strains produced detectable levels of aflatoxins at concentrations ranging from 12.00 to 3282.50 µg/kg (AFB1 + AFB2, while thirty two (91% F. verticillioides strains produced FB1 at concentrations ranging from 0.12 to 5.38 µg/g. Two F. proliferatum strains produced low fumonisin levels. The toxigenic potential of A. flavus (64.4% and F. verticillioides (91.5% strains observed in sorghum samples indicates that rigorous control should be directed at the storage conditions of these products to minimize contamination with toxigenic deteriorating fungi, preventing further hazard to human and animal health.A produção de aflatoxinas por 59 cepas de Aspergillus flavus e fumonisinas por 35 cepas de Fusarium verticillioides isoladas de amostras de grãos de sorgo recém colhido (10 amostras e armazenado (130 amostras, foram avaliadas. A detecção de aflatoxinas (AFB1 e AFB2 foi efetuada por Cromatografia em Camada Delgada (CCD e fumonisinas (FB1 e FB2 foram analisadas por Cromatografia Líquida de Alta Eficiência (CLAE. Os resultados demonstram a produção de AFB1 e AFB2 em 38 cepas (64,4% de A. flavus cujos níveis variaram de 12,00 a 3282,50 µg/kg. Referente às cepas de F. verticillioides, 32 (91% produziram FB1, nas concentrações de 0,12 a 5,38 µg/g. Baixos níveis de fumonisinas foram detectados em 2 cepas de F. proliferatum. A constatação da potencialidade toxígena das cepas de A. flavus (64,4% e de F. verticillioides (91,5% nesta investigação, revelam a importância da pesquisa de aflatoxinas e fumonisinas nas amostras de sorgo. Diante disto

  3. Evaluation of mRNA Expression Levels of cyp51A and mdr1, Candidate Genes for Voriconazole Resistance in Aspergillus flavus

    OpenAIRE

    Fattahi, Azam; Zaini, Farideh; Kordbacheh, Parivash; Rezaie, Sasan; Safara, Mahin; Fateh, Roohollah; Farahyar, Shirin; Kanani, Ali; Heidari, Mansour

    2015-01-01

    Background: Voriconazole Resistance (VRC-R) in Aspergillus flavus isolates impacts the management of aspergillosis, since azoles are the first choice for prophylaxis and therapy. However, to the best of our knowledge, the mechanisms underlying voriconazole resistance are poorly understood. Objectives: The present study was designed to evaluate mRNA expression levels of cyp51A and mdr1 genes in voriconazole resistant A. flavus by a Real-Time Reverse Transcriptase Polymerase Chain Reaction (RT-...

  4. Α-AMYLASES OF ASPERGILLUS FLAVUS VAR. ORYZA E AND BACILLUS SUBTILIS: THE SUBSTRATE SPECIFICITY AND RESISTANCE TO A NUMBER OF CHEMICALLY ACTIVE SUBSTANCES

    OpenAIRE

    Avdiyuk, K.; Varbanets, L.

    2013-01-01

    The ability of Aspergillus flavus var. oryzae 80428 and Bacillus subtilis 147 αІamylases to split different carbohydrateІcontaining substrates, such as maltose, sucrose, trehalose, dextrin, αІ and βІcyclodextrin, amylose, amylopectin, glyІ cogen, pullulan, soluble starch, insoluble starch, corn starch, wheat starch, dextran 500 has been studied. It was shown that investigated enzymes differ by substrate specificity. αІAmylase of A. flavus var. oryzae 80428 rapidly hydrolysed soluble potato an...

  5. 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. PMID:26338134

  6. The Master Transcription Factor mtfA Governs Aflatoxin Production, Morphological Development and Pathogenicity in the Fungus Aspergillus flavus

    Directory of Open Access Journals (Sweden)

    Zhenhong Zhuang

    2016-01-01

    Full Text Available Aspergillus flavus produces a variety of toxic secondary metabolites; among them, the aflatoxins (AFs are the most well known. These compounds are highly mutagenic and carcinogenic, particularly AFB1. A. flavus is capable of colonizing a number of economically-important crops, such as corn, cotton, peanut and tree nuts, and contaminating them with AFs. Molecular genetic studies in A. flavus could identify novel gene targets for use in strategies to reduce AF contamination and its adverse impact on food and feed supplies worldwide. In the current study, we investigated the role of the master transcription factor gene mtfA in A. flavus. Our results revealed that forced overexpression of mtfA results in a drastic decrease or elimination of several secondary metabolites, among them AFB1. The reduction in AFB1 was accompanied by a decrease in aflR expression. Furthermore, mtfA also regulates development; conidiation was influenced differently by this gene depending on the type of colonized substrate. In addition to its effect on conidiation, mtfA is necessary for the normal maturation of sclerotia. Importantly, mtfA positively affects the pathogenicity of A. flavus when colonizing peanut seeds. AF production in colonized seeds was decreased in the deletion mtfA strain and particularly in the overexpression strain, where only trace amounts were detected. Interestingly, a more rapid colonization of the seed tissue occurred when mtfA was overexpressed, coinciding with an increase in lipase activity and faster maceration of the oily part of the seed.

  7. Control of Aspergillus flavus Growth in Tomato Paste by Cinnamomum zeylanicum and Origanum vulgare L. Essential Oils

    Directory of Open Access Journals (Sweden)

    F Kalantary

    2014-05-01

    Full Text Available This study was conducted to evaluate the antifungal activities of cinnamon (Cinnamomum zeylanicum and oregano (Origanum vulgare L. essential oils against Aspergillus flavus in culture media and tomato paste. The chemical compositions of the essential oils were determined by Gas Chromatography-Mass Spectroscopy (GC-MS. Trans- cinnamaldehyde was found to be the main constituent of Cinnamomum zeylanicum essential oil (CZEO, followed by methyl eugenol, δ- cadinene and γ- cadinene. The major components of Origanum vulgare L. essential oil (OVEO were limonene, caryophyllene oxide, α-ionone, germacrene– D, γ- terpinene, β- pinene and terpinene-4-ol. For evaluating antifungal activities of CZEO and OVEO, A. flavus PTCC: 5006, was inoculated in Sabouraud Dextrose Broth (SDB and tomato paste, then 0, 50, 100, 200, 300, 400, 500 and 600 ppm of essential oils were added to each sample and incubated at 25±0.5oC for 30 and 60 days, respectively. The antifungal activity was measured by Agar Dilution method. The EOs at all tested concentrations had inhibitory effect against A. flavus growth. 200 ppm of CZEO and 500 ppm of OVEO completely inhibited A. flavus growth in culture media, while in tomato paste 300 ppm of CZEO and 200 ppm of OVEO had the same effect. Test panel evaluations were carried out in tomato ketchup base and samples with 100 and 200 ppm CZEO were accepted by panelists. The results may suggest the potential replacement of antifungal chemicals by CZEO as natural inhibitor to control A. flavus growth in tomato paste.

  8. Corn-Soybean Rotation Systems in the Mississippi Delta: Implications on Mycotoxin Contamination and Soil Populations of Aspergillus flavus

    Directory of Open Access Journals (Sweden)

    Hamed K. Abbas

    2012-01-01

    Full Text Available The effect of corn-soybean rotation on mycotoxin contamination in corn (Zea mays L. and soybean (Glycine max L. Merrill. grains has not been fully evaluated. Therefore, this research investigated the effect of corn-soybean rotation on aflatoxin and fumonisin contamination in respective grains. The results showed that aflatoxin levels in soybean averaged 2.3, <0.5, 0.6, and 6.8 ng/g in 2005, 2006, 2007, and 2008, while corn aflatoxin levels were 16.7, 37.1, 2.4, and 54.8 ng/g, respectively. Aspergillus flavus colonization was significantly greater (P≤0.05 in corn (log 1.9, 2.9, and 4.0 cfu/g compared to soybean (<1.3, 2.6, and 2.7 cfu/g in 2005, 2007, and 2008, respectively. Aflatoxigenic A. flavus isolates were more frequent in corn than in soybean in all four years. Higher fumonisin levels were found in corn (0.2 to 3.6 μg/g than in soybean (<0.2 μg/g. Rotating soybean with corn reduces the potential for aflatoxin contamination in corn by reducing A. flavus propagules in soil and grain and reducing aflatoxigenic A. flavus colonization. These results demonstrated that soybean grain is less susceptible to aflatoxin contamination compared to corn due to a lower level of colonization by A. flavus with a greater occurrence of non-aflatoxigenic isolates.

  9. Purification and Characterization of a Keratinase from a Feather-Degrading Fungus, Aspergillus flavus Strain K-03

    OpenAIRE

    Kim, Jeong-Dong

    2007-01-01

    A keratinolytic enzyme secreted by Aspergillus flavus K-03 cultured in feather meal basal medium (FMBM) containing 2% (w/v) chicken feather was purified and characterized. Keratinolytic enzyme secretion was the maximal at day 16 of the incubation period at pH 8 and 28℃. No relationship was detected between enzyme yield and increase of fungal biomass. The fraction obtained at 80% ammonium sulfate saturation showed 2.39-fold purification and was further purified by gel filtration in Sephadex G-...

  10. Aspergillus flavus Conidia-derived Carbon/Sulfur Composite as a Cathode Material for High Performance Lithium–Sulfur Battery

    OpenAIRE

    Maowen Xu; Min Jia; Cuiping Mao; Sangui Liu; Shujuan Bao; Jian Jiang; Yang Liu; Zhisong Lu

    2016-01-01

    A novel approach was developed to prepare porous carbon materials with an extremely high surface area of 2459.6 m2g−1 by using Aspergillus flavus conidia as precursors. The porous carbon serves as a superior cathode material to anchor sulfur due to its uniform and tortuous morphology, enabling high capacity and good cycle lifetime in lithium sulfur-batteries. Under a current rate of 0.2 C, the carbon-sulfur composites with 56.7 wt% sulfur loading deliver an initial capacity of 1625 mAh g−1, w...

  11. Treatment of two postoperative endophthalmitis cases due to Aspergillus flavus and Scopulariopsis spp. with local and systemic antifungal therapy

    Directory of Open Access Journals (Sweden)

    Uyar Guliz

    2007-07-01

    Full Text Available Abstract Background Endophthalmitis is the inflammatory response to invasion of the eye with bacteria or fungi. The incidence of endophthalmitis after cataract surgery varies between 0.072–0.13 percent. Treatment of endophthalmitis with fungal etiology is difficult. Case Presentation Case 1: A 71-year old male diabetic patient developed postoperative endophthalmitis due to Aspergillus flavus. The patient was treated with topical amphotericin B ophthalmic solution, intravenous (IV liposomal amphotericin-B and caspofungin following vitrectomy. Case 2: A 72-year old male cachectic patient developed postoperative endophthalmitis due to Scopulariopsis spp. The patient was treated with topical and IV voriconazole and caspofungin. Conclusion Aspergillus spp. are responsible of postoperative fungal endophthalmitis. Endophthalmitis caused by Scopulariopsis spp. is a very rare condition. The two cases were successfully treated with local and systemic antifungal therapy.

  12. Evaluation of viability of Aspergillus flavus and aflatoxins degradation in irradiated samples of maize Avaliação da viabilidade de Aspergillus flavus e degradação de aflatoxinas em amostras de milho irradiadas

    Directory of Open Access Journals (Sweden)

    Simone Aquino

    2005-12-01

    Full Text Available One of the currently most important fungi in stored grains is Aspergillus flavus, which produce aflatoxins. This fungus can grow on diverse substrates and represents a serious public health and animal nutritional problem. Therefore, the study of techniques that can be applied to the control of aflatoxins is of great importance. The objective of the present study was to determine the effects of gamma radiation on the growth of Aspergillus flavus Link and on degradation of aflatoxin B1 and B2 (AFB1 and AFB2 at a relative humidity of 97 99% and a water activity (Aw of 0.88-0.94. Samples of corn grains were irradiated using a cobalt 60 source emitting gamma rays at doses of 2, 5 and 10 kGy. Irradiation was found to be effective in reducing the number colony-forming units of A. flavus, per gram, in the corn samples analyzed. In addition, the fluorescent viability test (fluorescein diacetate and ethidium bromide revealed a decrease in the number of viable cells with increasing irradiation doses and three different fluorescence patterns. Furthermore, irradiation induced a partial reduction in AFB1 and AFB2 levels at the doses of 2 and 5 kGy, whereas complete degradation of aflatoxins was observed in the assay employing 10 kGy.Um dos fungos mais importantes atualmente em grãos armazenados é o Aspergillus flavus, o qual produz aflatoxinas. Este fungo pode crescer em diversos substratos e representa uma séria preocupação em saúde pública e nutrição animal. Portanto, o estudo de técnicas que possam ser aplicadas no controle das aflatoxinas é de grande importância. Assim sendo, o objetivo do presente trabalho foi estudar os efeitos da radiação gama no crescimento de Aspergillus flavus Link e na degradação das aflatoxinas B1 e B2, (AFB1 e AFB2 em umidade relativa (UR de 97-99% e atividade de água (Aa de 0,88-0,94. Amostras de grãos de milho foram irradiadas, utilizando-se uma fonte de Cobalto 60, emissora de raios gama, com as doses de 2; 5

  13. Differentiation between Aspergillus flavus and Aspergillus parasiticus from Pure Culture and Aflatoxin-Contaminated Grapes Using PCR-RFLP Analysis of aflR-aflJ Intergenic Spacer

    International Nuclear Information System (INIS)

    Aflatoxins (AFs) represent the most important single mycotoxin-related food safety problem in developed and developing countries as they have adverse effects on human and animal health. They are produced mainly by Aspergillus flavus and A. parasiticus. Both species have different aflatoxinogenic profile. In order to distinguish between A. flavus and A. parasiticus, gene-specific primers were designed to target the intergenic spacer (IGS) for the AF biosynthesis genes, aflJ and aflR. Polymerase chain reaction (PCR) products were subjected to restriction endonuclease analysis using BglII to look for restriction fragment length polymorphisms (RFLPs). Our result showed that both species displayed different PCR-based RFLP (PCR-RFLP) profile. PCR products from A. flavus cleaved into 3 fragments of 362, 210, and 102 bp. However, there is only one restriction site for this enzyme in the sequence of A. parasiticus that produced only 2 fragments of 363 and 311 bp. The method was successfully applied to contaminated grapes samples. This approach of differentiating these 2 species would be simpler, less costly, and quicker than conventional sequencing of PCR products and/or morphological identification. (author)

  14. Effect of gamma irradiation on growth and aflatoxin production by certain local aflatoxigenic isolates of aspergillus flavus

    International Nuclear Information System (INIS)

    The radiation D10 values of two aflatoxigenic isolates of aspergillus flavus (No. 1 and No. 184) were determined. The D10 -value of A. flavus isolate No.1 was found to be 0.43 and 0.50 kGy in physiological saline soulution and smoked herrings, while the D10 - value of A. SFlavus isolateNo. 184 was 0.53 and -0.62 KGy in saline solution and raisins, respectively. The irradiated (0.05, 1.0, 1.5, 2.0, 2.5, 3.0 and 3.5 KGy) and non-irradiated spores of two fungi were separately inoculated into rice-corn steep liquor and incubated at 28 degree C for 12 days. The fungal mycelial dry weight, as a function of growth, decreased with increasing gamma irradiation doses. Irradiation doses used gratly reduced aflatoxins formation. Smoked herrings and raisins were inoculated with spores of A. flavus isolated No.1 and No.184, respectively, then irradiated at 1.5, 3.0 and 4.5 KGy and stored for two months at room temperature. It was found that a gamma irradiation dose of 1.5 KGy greatly reduced the amount of aflatoxins produced, while 3.0 and 4.5 KGy completely prevented aflatoxin formation

  15. A Caleosin-Like Protein with Peroxygenase Activity Mediates Aspergillus flavus Development, Aflatoxin Accumulation, and Seed Infection.

    Science.gov (United States)

    Hanano, Abdulsamie; Almousally, Ibrahem; Shaban, Mouhnad; Blee, Elizabeth

    2015-09-01

    Caleosins are a small family of calcium-binding proteins endowed with peroxygenase activity in plants. Caleosin-like genes are present in fungi; however, their functions have not been reported yet. In this work, we identify a plant caleosin-like protein in Aspergillus flavus that is highly expressed during the early stages of spore germination. A recombinant purified 32-kDa caleosin-like protein supported peroxygenase activities, including co-oxidation reactions and reduction of polyunsaturated fatty acid hydroperoxides. Deletion of the caleosin gene prevented fungal development. Alternatively, silencing of the gene led to the increased accumulation of endogenous polyunsaturated fatty acid hydroperoxides and antioxidant activities but to a reduction of fungal growth and conidium formation. Two key genes of the aflatoxin biosynthesis pathway, aflR and aflD, were downregulated in the strains in which A. flavus PXG (AfPXG) was silenced, leading to reduced aflatoxin B1 production in vitro. Application of caleosin/peroxygenase-derived oxylipins restored the wild-type phenotype in the strains in which AfPXG was silenced. PXG-deficient A. flavus strains were severely compromised in their capacity to infect maize seeds and to produce aflatoxin. Our results uncover a new branch of the fungal oxylipin pathway and may lead to the development of novel targets for controlling fungal disease. PMID:26116672

  16. The major volatile compound 2-phenylethanol from the biocontrol yeast Pichia anomala inhibits growth and expression of aflatoxin biosynthetic genes of Aspergillus flavus

    Science.gov (United States)

    Aspergillus flavus is a globally distributed fungus and an important food contaminant because it produces the most potent natural carcinogenic compound known as aflatoxin (AF) B1. The major volatile from a yeast strain, Pichia anomala WRL-076 was identified by SPEM-GC/MS analysis to be 2-phenylethan...

  17. The two genome sequence release and blast server construction for aflatoxin-producing L and S strains Aspergillus parasiticus and A. flavus

    Science.gov (United States)

    Aflatoxins are toxic and carcinogenic secondary metabolites. These compounds, produced by Aspergillus flavus and A. parasiticus, contaminate pre-harvest agricultural crops in the field and post-harvest grains during storage. In order to reduce and eliminate aflatoxin contamination of food and feed...

  18. RNAi silencing of the 14 kDa trypsin inhibitor protein in maize and its effect on host resistance against Aspergillus flavus infection/aflatoxin production

    Science.gov (United States)

    Maize (Zea mays L.) is one of the major crops susceptible to Aspergillus flavus Link ex. Fries infection and subsequent aflatoxin contamination. Previous studies found the expression of an antifungal 14 kDa trypsin inhibitor (TI) was associated with maize aflatoxin resistance. To further investigate...

  19. Genetic Analysis of the Resistance to Aspergillus flavus Infection in Maize (Zea mays L.)

    Institute of Scientific and Technical Information of China (English)

    DENG De-xiang; JIANG Si-xia; WANG Yi-jun; BIAN Yun-long; CHEN Jian-jian; JIA Bo

    2009-01-01

    Maize (Zea mays L.),one of main crops in the world,is easily susceptible to Aspergillusflavus (Link:fr) infection,resulting huge loses worldwide.Breeding for A.flavus resistance has been proved an efficient way to solve the problem of aflatoxin contamination.Genetic analysis of the sources of resistance to A.flavus in maize is necessary for this purpose.The complete diallel crosses of 6 inbred lines with different resistance to A.flavus infection were implemented.Inoculation categorical data of each cross were analyzed with the additive-dominant and additive-dominant-epitasis genetic models.Results indicated some crosses fitted the 2 major genes with additive-dominant-epitasis genetic model.Others fitted the major gene and polygene mixed model.Moreover,the additive,dominant,and epitasis effects varied in crosses.The A.flavus resistance was controlled by both major gene and polygene.

  20. The potential inhibitory effect of cuminum cyminum, ziziphora clinopodioides and nigella sativa essential oils on the growth of Aspergillus fumigatus and Aspergillus flavus

    Directory of Open Access Journals (Sweden)

    A.R Khosravi

    2011-03-01

    Full Text Available The goals of this study were to evaluate the effectiveness of Cuminum cyminum, Ziziphora clinopodioides and Nigella sativa essential oils to inhibit the growth of Aspergillus fumigatus and A. flavus and to evoke ultrastructural changes. The fungi were cultured into RPMI 1640 media in the presence of oils at concentrations of 8, 6, 5, 4, 3, 2, 1.5, 1.25, 1, 0.75 and 0.5 mg/ml in broth microdilution and 2, 1.5, 1 and 0.5 mg/ml in broth macrodilution methods with shaking for 48 h at 28ºC. Conidial and mycelial samples exposed to 0.25, 0.5, 1, 1.5 and 2 mg essential oils/ml for 5 days in 2% yeast extract granulated plus 15% Saccharose media were processed for transmission electron microscopy (TEM. Based on broth dilution methods, C. cyminum and to a lesser extent Z. clinopodioides oils exhibited the strongest activity against A. fumigatus and A. flavus with MIC90 ranging from 0.25 to 1.5 mg/ml, while the oil from N. sativa exhibited relatively moderate activity against two above fungi with MIC90 ranging from 1.5 to 2 mg/ml. The main changes observed by TEM were in the cell wall, plasma membrane and membranous organelles; in particular, in the nuclei and mitochondria. These modifications in fungal structure were associated with the interference of the essential oils with the enzymes responsible for cell wall synthesis, which disturbed normal growth. Moreover, the essential oils caused high vacuolation of the cytoplasm, detachment of fibrillar layer of cell wall, plasma membrane disruption and disorganization of the nuclear and mitochondrial structures. Aspergillus fumigatus and A. flavus growth inhibition induced by these oils were found to be well-correlated with subsequent morphological changes of the fungi exposed to different fungistatic concentrations of the oils. Our results show the anti-Aspergillus activities of C. cyminum, Z. clinopodioides and N. sativa essential oils, which strengthens the potential use of these substances as anti

  1. Nanocapsular Dispersion of Cinnamaldehyde for Enhanced Inhibitory Activity against Aflatoxin Production by Aspergillus flavus

    Directory of Open Access Journals (Sweden)

    Hongbo Li

    2015-04-01

    Full Text Available Cinnamaldehyde (CA is marginally soluble in water, making it challenging to evenly disperse it in foods, and resulting in lowered anti-A. flavus efficacy. In the present study, nano-dispersed CA (nano-CA was prepared to increase its aqueous solubility. Free and nano-dispersed CA were compared in terms of their inhibitory activity against fungal growth and aflatoxin production of A. flavus both in Sabouraud Dextrose (SD culture and in peanut butter. Our results indicated that free CA inhibited the mycelia growth and aflatoxin production of A. flavus with a minimal inhibitory concentration (MIC value of 1.0 mM, but promoted the aflatoxin production at some concentrations lower than the MIC. Nano-CA had a lower MIC value of 0.8 mM against A. flavus, and also showed improved activity against aflatoxin production without the promotion at lower dose. The solidity of peanut butter had an adverse impact on the antifungal activity of free CA, whereas nano-dispersed CA showed more than 2-fold improved activity against the growth of A. flavus. Free CA still promoted AFB1 production at the concentration of 0.25 mM, whereas nano-CA showed more efficient inhibition of AFB1 production in the butter.

  2. Non-aflatoxigenic Aspergillus flavus as potential biocontrol agents to reduce aflatoxin contamination in peanuts harvested in Northern Argentina.

    Science.gov (United States)

    Alaniz Zanon, María Silvina; Barros, Germán Gustavo; Chulze, Sofía Noemí

    2016-08-16

    Biological control is one of the most promising strategies for preventing aflatoxin contamination in peanuts at field stage. A population of 46 native Aspergillus flavus nonaflatoxin producers were analysed based on phenotypic, physiological and genetic characteristics. Thirty-three isolates were characterized as L strain morphotype, 3 isolates as S strain morphotype, and 10 isolates did not produce sclerotia. Only 11 of 46 non-aflatoxigenic isolates did not produce cyclopiazonic acid. The vegetative compatibility group (VCG) diversity index for the population was 0.37. For field trials we selected the non-aflatoxigenic A. flavus AR27, AR100G and AFCHG2 strains. The efficacy of single and mixed inocula as potential biocontrol agents in Northern Argentina was evaluated through a 2-year study (2014-2015). During the 2014 peanut growing season, most of the treatments reduced the incidence of aflatoxigenic strains in both soil and peanut kernel samples, and no aflatoxin was detected in kernels. During the 2015 growing season, there was a reduction of aflatoxigenic strains in kernel samples from the plots treated with the potential biocontrol agents. Reductions of aflatoxin contamination between 78.36% and 89.55% were observed in treated plots in comparison with the un-inoculated control plots. This study provides the first data on aflatoxin biocontrol based on competitive exclusion in the peanut growing region of Northern Argentina, and proposes bioproducts with potential use as biocontrol agents. PMID:27220011

  3. Variabilidade de produção de aflatoxinas por linhagens de Aspergillus flavus em diferentes tempos de manutenção Aflatoxin production variability by Aspergillus flavus strains after different storage times

    Directory of Open Access Journals (Sweden)

    M.H. Taniwaki

    1993-05-01

    Full Text Available O presente trabalho fui realizado com a finalidade de se estudar a produção de aflatoxinas por linhagens de A. flavus, recém isoladas, em diferentes tempos de manutenção, a fim de contribuir para um melhor entendimento do mecanismo de variação na produção de aflatoxinas. Para isso, foram utilizadas três linhagens de A. flavus produtoras de aflatoxinas, classificadas como: a grande produtora; b média produtora e c baixa produtora. Neste experimento, que se estendeu por 280 dias, os fungos foram estudados em dois métodos de preservação: mantido em óleo mineral, no meio Czapeck, e repicado periodicamente em meio Czapeck modificado. A análise da produção de aflatoxinas foi efetuada de 30 em 30 dias. A quantificação da toxina foi feita por cromatografía em camada delgada, pela técnica de avaliação visual, de diluição até extinção. Foi constatada uma variação na produção de toxina em todas as linhagens, contudo elas não perderam suas características originais.Aflatoxin production by strains recently isolated of Aspergillus flavus was studied, after different storage times understand the mechanisms of possible variations in aflatoxin production. Three A. flavus aflatoxin producing strains were utilized, classified as: a high producer; b medium producer and c low producer. The experiment lasted 280 days and the moulds were studied by two preservation methods: oil covered slants on Czapeck's medium and periodic transfer on Czapeck's modified medium. Quantification of the aflatoxin produced was made at 30 day intervals, on thin-layer chromatography and visual determination by the dilution-to-extinction technique. The production of aflatoxin by all strains varied but they did not lose their initial characteristics. Microscopic examinations revealed thickened zones and hifal enlargements over some globous structures that may be related to aflatoxin production sites.

  4. Effects of gamma radiation and electron beam on samples of the Brazil nuts artificially inoculated with Aspergillus flavus; Efeitos da radiacao gama e feixe de eletrons sobre amostras de castanhas-do-Brasil inoculadas artificialmente com Aspergillus flavus

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, Ednei Assuncao Antunes

    2012-07-01

    The high level of contamination by aflatoxin produced by fungi in lots of Brazil nuts and the strict control by importing countries in relation to the levels of toxins in food, European Union countries decided in 2003 by the return of these lots products from Brazil. Despite the economic loss represented by contamination by toxigenic fungi in Brazil nuts, a major product of extractive Northern of Brazil, studies are still preliminary as the control of contamination aflatoxigenic fungal using methods such as gamma radiation (G.R) and mainly, electron beam (E.B). These facts motivated this research, which aimed to evaluate the effects of gamma radiation and application of electron beam in samples of Brazil nut artificially inoculated with Aspergillus flavus. This goal, we were studied 50 samples of the Brazil nut previously inoculated with spores of A. flavus and subsequently incubated at 30 °C in relative humidity controlled at 93%. After incubation, period of 15 days, the average water activity of the samples was 0.80, the samples were divided into 5 groups that received the following doses of radiation: control (0 kGy), 5 and 10 kGy 5 E.B and G.R. The mycobiota was performed by serial dilution, plated on surface using potato dextrose agar. The results demonstrated that treatment with E.B using a dose of 5 kGy and 10 kGy resulted in reduced growth of A. flavus in 74% (37/50) and 94% (47/50) of samples. The samples treated with G.R at the dose of 5 kGy and 10 kGy no fungal growth occurred in 92% (46/50) 100% (50/50) of. The study of aflatoxins showed that doses of E.B of 5 kGy and 10 kGy reduced levels of AFB1 at 53.32% and 65.66% respectively. The application of gamma rays at doses of 5 and 10 kGy reduced levels of toxins in 70.61% and 84.15% respectively. This result may be attributed to higher penetrability of gamma radiation. Sensory analysis showed greater acceptance of the judges for the samples irradiated with E.B and G.R at the dose of 10 kGy. We concluded

  5. Inhibition of the Aspergillus flavus Growth and Aflatoxin B1 Contamination on Pistachio Nut by Fengycin and Surfactin-Producing Bacillus subtilis UTBSP1

    Science.gov (United States)

    Farzaneh, Mohsen; Shi, Zhi-Qi; Ahmadzadeh, Masoud; Hu, Liang-Bin; Ghassempour, Alireza

    2016-01-01

    In this study, the treatment of pistachio nuts by Bacillus subtilis UTBSP1, a promising isolate to degrade aflatoxin B1 (AFB1), caused to reduce the growth of Aspergillus flavus R5 and AFB1 content on pistachio nuts. Fluorescence probes revealed that the cell free supernatant fluid from UTBSP1 affects spore viability considerably. Using high-performance liquid chromatographic (HPLC) method, 10 fractions were separated and collected from methanol extract of cell free supernatant fluid. Two fractions showed inhibition zones against A. flavus. Mass spectrometric analysis of the both antifungal fractions revealed a high similarity between these anti-A. flavus compounds and cyclic-lipopeptides of surfactin, and fengycin families. Coproduction of surfactin and fengycin acted in a synergistic manner and consequently caused a strong antifungal activity against A. flavus R5. There was a positive significant correlation between the reduction of A. flavus growth and the reduction of AFB1 contamination on pistachio nut by UTBSP1. The results indicated that fengycin and surfactin-producing B. subtilis UTBSP1 can potentially reduce A. flavus growth and AFB1 content in pistachio nut. PMID:27298596

  6. Characterization of AFLAV, a Tfl/Sushi retrotransposon from Aspergillus flavus

    Science.gov (United States)

    The insert of pAF28 contains a 4.5 kb region which encodes a truncated retrotransposon (AfRTL-1). In search for a full-length and intact copy of retrotransposon, we exploited a novel PCR cloning strategy by amplifying a 3.4 kb region from the genomic DNA of A. flavus NRRL 6541. The fragment was cl...

  7. Mycotoxin production and predictive modelling kinetics on the growth of Aspergillus flavus and Aspergillus parasiticus isolates in whole black peppercorns (Piper nigrum L).

    Science.gov (United States)

    Yogendrarajah, Pratheeba; Vermeulen, An; Jacxsens, Liesbeth; Mavromichali, Evangelia; De Saeger, Sarah; De Meulenaer, Bruno; Devlieghere, Frank

    2016-07-01

    The growth and mycotoxin production of three Aspergillus flavus isolates and an Aspergillus parasiticus isolate were studied in whole black peppercorns (Piper nigrum L.) using a full factorial design with seven water activity (aw) (0.826-0.984) levels and three temperatures (22, 30 and 37°C). Growth rates and lag phases were estimated using linear regression. Diverse secondary models were assessed for their ability to describe the radial growth rate as a function of individual and combined effect of aw and temperature. Optimum radial growth rate ranged from 0.75±0.04 to 2.65±0.02mm/day for A. flavus and 1.77±0.10 to 2.50±0.10mm/day for A. parasiticus based on the Rosso cardinal estimations. Despite the growth failure of some isolates at marginal conditions, all the studied models showed good performance to predict the growth rates. Validation of the models was performed on independently derived data. The bias factors (0.73-1.03), accuracy factors (0.97-1.36) and root mean square error (0.050-0.278) show that the examined models are conservative predictors of the colony growth rate of both fungal species in black peppers. The Rosso cardinal model can be recommended to describe the individual aw effect while the extended Gibson model was the best model for describing the combined effect of aw and temperature on the growth rate of both fungal species in peppercorns. Temperature optimum ranged from 30 to 33°C, while aw optimum was 0.87-0.92 as estimated by multi-factorial cardinal model for both species. The estimated minimum temperature and aw for A. flavus and A. parasiticus for growth were 11-16°C and 0.73-0.76, respectively, hence, achieving these conditions should be considered during storage to prevent the growth of these mycotoxigenic fungal species in black peppercorns. Following the growth study, production of mycotoxins (aflatoxins B1, B2, G1, G2, sterigmatocystin and O-methyl sterigmatocystin (OMST)) was quantified using LC-MS/MS. Very small

  8. Effects of gamma radiation and electron beam on samples of the Brazil nuts artificially inoculated with Aspergillus flavus

    International Nuclear Information System (INIS)

    The high level of contamination by aflatoxin produced by fungi in lots of Brazil nuts and the strict control by importing countries in relation to the levels of toxins in food, European Union countries decided in 2003 by the return of these lots products from Brazil. Despite the economic loss represented by contamination by toxigenic fungi in Brazil nuts, a major product of extractive Northern of Brazil, studies are still preliminary as the control of contamination aflatoxigenic fungal using methods such as gamma radiation (G.R) and mainly, electron beam (E.B). These facts motivated this research, which aimed to evaluate the effects of gamma radiation and application of electron beam in samples of Brazil nut artificially inoculated with Aspergillus flavus. This goal, we were studied 50 samples of the Brazil nut previously inoculated with spores of A. flavus and subsequently incubated at 30 °C in relative humidity controlled at 93%. After incubation, period of 15 days, the average water activity of the samples was 0.80, the samples were divided into 5 groups that received the following doses of radiation: control (0 kGy), 5 and 10 kGy 5 E.B and G.R. The mycobiota was performed by serial dilution, plated on surface using potato dextrose agar. The results demonstrated that treatment with E.B using a dose of 5 kGy and 10 kGy resulted in reduced growth of A. flavus in 74% (37/50) and 94% (47/50) of samples. The samples treated with G.R at the dose of 5 kGy and 10 kGy no fungal growth occurred in 92% (46/50) 100% (50/50) of. The study of aflatoxins showed that doses of E.B of 5 kGy and 10 kGy reduced levels of AFB1 at 53.32% and 65.66% respectively. The application of gamma rays at doses of 5 and 10 kGy reduced levels of toxins in 70.61% and 84.15% respectively. This result may be attributed to higher penetrability of gamma radiation. Sensory analysis showed greater acceptance of the judges for the samples irradiated with E.B and G.R at the dose of 10 kGy. We concluded

  9. [Effect of alcoholic extracts of wild plants on the inhibition of growth of Aspergillus flavus, Aspergillus niger, Penicillium chrysogenum, Penicillium expansum, Fusarium moniliforme and Fusarium poae moulds].

    Science.gov (United States)

    Tequida-Meneses, Martín; Cortez-Rocha, Mario; Rosas-Burgos, Ema Carina; López-Sandoval, Susana; Corrales-Maldonado, Consuelo

    2002-06-01

    Fungicidal activity of wild plants Larrea tridentata, Karwinskia humboldtiana, Ricinus communis, Eucalyptus globulus, Ambrosia ambrosioides, Nicotiana glauca, Ambrosia confertiflora, Datura discolor, Baccharis glutinosa, Proboscidea parviflora, Solanum rostratum, Jatropha cinerea, Salpianthus macrodonthus y Sarcostemma cynanchoides was evaluated against the moulds species Aspergillus flavus, Aspergillus niger, Penicillium chrysogenum, Penicillium expansum, Fusarium poae y Fusarium moniliforme moulds species. Alcoholic extracts 6% (w/v) were prepared using six grams of dried plant powders (leaves and stems) and alcohol (70% ethanol or 70% methanol). A spore suspension (1x10(6); ufc/ml) of each mould was prepared by adding saline solution (0.85%) and 0.1% tween 80. The extracts were mixed with Czapeck yeast agar (CYA) at 45-50 degrees C in 1:10 relation on Petri dishes. Triplicate Petri dishes of each treatment and for each mould were centrally inoculated and three Petri dishes were used without treatment as controls. The inoculated dishes and controls were incubated at 25 +/- 2 degrees C for eight days. The incubated dishes were examined each 48 h and after the colony diameter (radial growth) was measured. Two mould species were controlled by L. tridentata, B. glutinosa and P. parviflora. Extracts of L. tridentata in methanol or ethanol at 41.5-100% inhibited all six species of moulds. PMID:12828509

  10. rtfA, a putative RNA-Pol II transcription elongation factor gene, is necessary for normal morphological and chemical development in Aspergillus flavus.

    Science.gov (United States)

    Lohmar, Jessica M; Harris-Coward, Pamela Y; Cary, Jeffrey W; Dhingra, Sourabh; Calvo, Ana M

    2016-06-01

    The filamentous fungus Aspergillus flavus is an agriculturally important opportunistic plant pathogen that produces potent carcinogenic compounds called aflatoxins. We identified the A. flavus rtfA gene, the ortholog of rtf1 in Saccharomyces cerevisiae and rtfA in Aspergillus nidulans. Interestingly, rtfA has multiple cellular roles in this mycotoxin-producing fungus. In this study, we show that rtfA regulates conidiation. The rtfA deletion mutant presented smaller conidiophores with significantly reduced conidial production compared to the wild-type strain. The absence of rtfA also resulted in a significant decrease or lack of sclerotial production under conditions that allowed abundant production of these resistance structures in the wild type. Importantly, the deletion of rtfA notably reduced the production of aflatoxin B1, indicating that rtfA is a regulator of mycotoxin biosynthesis in A. flavus. In addition, the deletion rtfA also altered the production of several unknown secondary metabolites indicating a broader regulatory scope. Furthermore, our study revealed that rtfA controls the expression of the global regulators veA and laeA, which further influence morphogenesis and secondary metabolism in A. flavus. PMID:27020290

  11. Efficacy of aqueous garlic extract on growth, aflatoxin B1 production, and cyto-morphological aberrations of Aspergillus flavus, causing human ophthalmic infection: topical treatment of A. flavus keratitis.

    Science.gov (United States)

    Ismaiel, Ahmed A; Rabie, Gamal H; Kenawey, Saied E M; Abd El-Aal, Marwa A

    2012-10-01

    By using agar well diffusion assay, antifungal activity of aqueous extract prepared from Egyptian garlic (Allium sativum L.) was evaluated in vitro against two strains of Aspergillus flavus (OC1 and OC10) causing human ocular infection. The recorded minimum inhibitory concentration (MIC) for growth inhibition of both strains was 3.60 mg/ml. Aqueous garlic extract (AGE) was used in successive in vivo tests as an attempt to cure rabbit's fungal keratitis caused by A. flavus OC1. Findings showed that diluted preparation of AGE was effective topical antifungal agent and succeeded to cure severe A. flavus keratitis in a time course less than 10 days without any observable side effects. Microscopic examination showed that AGE induced deleterious cyto-morphological aberrations in A. flavus target cells. AGE applied to Czapek's broth via contact method was more effective on growth, spores and aflatoxin B1 production than AGE applied to the same broth at the same concentration via fumigation method. PMID:24031964

  12. Nutritional changes in powdered red pepper upon in vitro infection of Aspergillus flavus Alterações nutricionais em pimenta vermelha em pó após infecção in vitro com Aspergillus flavus

    Directory of Open Access Journals (Sweden)

    Smita Tripathi

    2009-03-01

    Full Text Available Quantitative losses in various biochemical constituents like capsaicin, carotenes, ascorbic acid, polyphenols, mineral matter, sugars (soluble and insoluble, protein and fat were estimated after the successful growth of Aspergillus flavus for 30 days on powdered red pepper. The fungal biomass was measured by ergosterol content and Aflatoxin B1 by HPLC. Amongst the various nutritional constituents evaluated for nutritional losses and changes the highest nutritional loss was reported in total carotenoids (88.55% followed by total sugars (85.5%. The protein content of the infected sample increased from 18.01% to 23%. The nutritional profile of chilli powder (Capsicum annum var. sannam L. shows highest share of total soluble sugars (32.89% and fiber content (21.05%, followed by protein (18.01% and fat (13.32% making it an ideal solid - substrate for mould growth. At the end of incubation the fungal biomass was 192. 25 mg / 100 gram powder, total plate count 17.5 X 10 4 CFU/g and Aflatoxin B1 content was 30.06 µg / kg.Foram avaliadas as perdas de vários constituintes bioquímicos como capsaicina, carotenos, acido ascórbico, polifenóis, matéria orgânica, açucares (solúveis e insolúveis, proteína e gordura em pimenta vermelha em pó após a multiplicação de Aspergillus flavus por 30 dias. A biomassa fúngica foi mensurada pelo conteúdo de ergosterol e aflatoxina por HPLC. Entre os vários constituintes avaliados, a maior perda foi a de carotenóides totais (88,55%, seguido de açucares totais (85,5%. O conteúdo protéico da amostra infectada aumentou de 18,01% para 23%. O perfil nutricional da pimenta em pó (Capsicum annum var. sannam L. indica alto teor de açucares totais (32,89% e fibras (21,05%, seguido de proteína (18,01% e gordura (13,32%, tornando-a um substrato ideal para crescimento de fungos. Ao final dos 30 dias, a biomassa fúngica foi 192,25 mg/100g, a contagem total em placas foi 17,5 x 10(4 CFU/g e o conteúdo de

  13. Intraspecific aflatoxin inhibition in Aspergillus flavus is thigmoregulated, independent of vegetative compatibility group and is strain dependent.

    Directory of Open Access Journals (Sweden)

    Changwei Huang

    Full Text Available Biological control of preharvest aflatoxin contamination by atoxigenic stains of Aspergillus flavus has been demonstrated in several crops. The assumption is that some form of competition suppresses the fungus's ability to infect or produce aflatoxin when challenged. Intraspecific aflatoxin inhibition was demonstrated by others. This work investigates the mechanistic basis of that phenomenon. A toxigenic and atoxigenic isolate of A. flavus which exhibited intraspecific aflatoxin inhibition when grown together in suspended disc culture were not inhibited when grown in a filter insert-plate well system separated by a .4 or 3 µm membrane. Toxigenic and atoxigenic conidial mixtures (50∶50 placed on both sides of these filters restored inhibition. There was ∼50% inhibition when a 12 µm pore size filter was used. Conidial and mycelial diameters were in the 3.5-7.0 µm range and could pass through the 12 µm filter. Larger pore sizes in the initially separated system restored aflatoxin inhibition. This suggests isolates must come into physical contact with one another. This negates a role for nutrient competition or for soluble diffusible signals or antibiotics in aflatoxin inhibition. The toxigenic isolate was maximally sensitive to inhibition during the first 24 hrs of growth while the atoxigenic isolate was always inhibition competent. The atoxigenic isolate when grown with a green fluorescent protein (GFP toxigenic isolate failed to inhibit aflatoxin indicating that there is specificity in the touch inhibiton. Several atoxigenic isolates were found which inhibited the GFP isolate. These results suggest that an unknown signaling pathway is initiated in the toxigenic isolate by physical interaction with an appropriate atoxigenic isolate in the first 24 hrs which prevents or down-regulates normal expression of aflatoxin after 3-5 days growth. We suspect thigmo-downregulation of aflatoxin synthesis is the mechanistic basis of intraspecific

  14. Transcriptional Profiles Uncover Aspergillus flavus-Induced Resistance in Maize Kernels

    Directory of Open Access Journals (Sweden)

    Zhi-Yuan Chen

    2011-06-01

    Full Text Available Aflatoxin contamination caused by the opportunistic pathogen A. flavus is a major concern in maize production prior to harvest and through storage. Previous studies have highlighted the constitutive production of proteins involved in maize kernel resistance against A. flavus’ infection. However, little is known about induced resistance nor about defense gene expression and regulation in kernels. In this study, maize oligonucleotide arrays and a pair of closely-related maize lines varying in aflatoxin accumulation were used to reveal the gene expression network in imbibed mature kernels in response to A. flavus’ challenge. Inoculated kernels were incubated 72 h via the laboratory-based Kernel Screening Assay (KSA, which highlights kernel responses to fungal challenge. Gene expression profiling detected 6955 genes in resistant and 6565 genes in susceptible controls; 214 genes induced in resistant and 2159 genes induced in susceptible inoculated kernels. Defense related and regulation related genes were identified in both treatments. Comparisons between the resistant and susceptible lines indicate differences in the gene expression network which may enhance our understanding of the maize-A. flavus interaction.

  15. Inhibition of aflatoxin biosynthesis in Aspergillus flavus by phenolic compounds extracted of Piper betle L.

    Directory of Open Access Journals (Sweden)

    Darab Yazdani

    2013-12-01

    Full Text Available Food contamination by aflatoxins is an important food safety concern for agricultural products. In order to identify and develop novel antifungal agents, several plant extracts and isolated compounds have been evaluated for their bioactivities. Anti-infectious activity of Piper betle used in traditional medicine of Malaysia has been reported previously.Crude methanol extract from P. betel powdered leaves was partitioned between chloroform and water. The fractions were tested against A. flavus UPMC 89, a strong aflatoxin producing strain. Inhibition of mycelial growth and aflatoxin biosynthesis were tested by disk diffusion and macrodillution techniques, respectively. The presence of aflatoxin was determined by thin-layer chromatography (TLC and fluorescence spectroscopy techniques using AFB1 standard. The chloroform soluble compounds were identified using HPLC-Tandem mass spectrometry technique.The results, evaluated by measuring the mycelial growth and quantification of aflatoxin B1(AFLB1 production in broth medium revealed that chloroform soluble compounds extract from P. betle dried leaves was able to block the aflatoxin biosynthesis pathway at concentration of 500μg/ml without a significant effect on mycelium growth. In analyzing of this effective fractions using HPLC-MS(2 with ESI ionization technique, 11 phenolic compounds were identified.The results showed that the certain phenolic compounds are able to decline the aflatoxin production in A. flavus with no significant effect on the fungus mycelia growth. The result also suggested P. betle could be used as potential antitoxin product.

  16. Efficacy of a coating composed of chitosan from Mucor circinelloides and carvacrol to control Aspergillus flavus and the quality of cherry tomato fruits.

    Science.gov (United States)

    de Souza, Evandro L; Sales, Camila V; de Oliveira, Carlos E V; Lopes, Laênia A A; da Conceição, Maria L; Berger, Lúcia R R; Stamford, Thayza C M

    2015-01-01

    Cherry tomato (Lycopersicon esculentum Mill) fruits are susceptible to contamination by Aspergillus flavus, which may cause the development of fruit rot and significant postharvest losses. Currently there are significant drawbacks for the use of synthetic fungicides to control pathogenic fungi in tomato fruits, and it has increased the interest in exploring new alternatives to control the occurrence of fungal infections in these fruits. This study evaluated the efficacy of chitosan (CHI) from Mucor circinelloides in combination with carvacrol (CAR) in inhibiting A. flavus in laboratory media and as a coating on cherry tomato fruits (25°C, 12 days and 12°C, 24 days). During a period of storage, the effect of coatings composed of CHI and CAR on autochthonous microflora, as well as on some quality characteristics of the fruits such as weight loss, color, firmness, soluble solids, and titratable acidity was evaluated. CHI and CAR displayed MIC valuesof 7.5 mg/mL and 10 μL/mL, respectively, against A. flavus. The combined application of CHI (7.5 or 3.75 mg/mL) and CAR (5 or 2.5 μL/mL) strongly inhibited the mycelial growth and spore germination of A. flavus. The coating composed of CHI (3.75 mg/mL) and CAR (2.5 or 1.25 μL/mL) inhibited the growth of A. flavus in artificially contaminated fruits, as well as the native fungal microflora of the fruits stored at room or low temperature. The application of the tested coatings preserved the quality of cherry tomato fruits as measured by some physicochemical attributes. From this, composite coatings containing CHI and CAR offer a promising alternative to control postharvest infection caused by A. flavus or native fungal microflora in fresh cherry tomato fruits without negatively affecting their quality over storage. PMID:26257717

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

    International Nuclear Information System (INIS)

    In the process of the fermentation of steroid C11α-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 1015 ions/cm2, 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)

  18. Aspergillus flavus Conidia-derived Carbon/Sulfur Composite as a Cathode Material for High Performance Lithium-Sulfur Battery

    Science.gov (United States)

    Xu, Maowen; Jia, Min; Mao, Cuiping; Liu, Sangui; Bao, Shujuan; Jiang, Jian; Liu, Yang; Lu, Zhisong

    2016-01-01

    A novel approach was developed to prepare porous carbon materials with an extremely high surface area of 2459.6 m2g-1 by using Aspergillus flavus conidia as precursors. The porous carbon serves as a superior cathode material to anchor sulfur due to its uniform and tortuous morphology, enabling high capacity and good cycle lifetime in lithium sulfur-batteries. Under a current rate of 0.2 C, the carbon-sulfur composites with 56.7 wt% sulfur loading deliver an initial capacity of 1625 mAh g-1, which is almost equal to the theoretical capacity of sulfur. The good performance may be ascribed to excellent electronic networks constructed by the high-surface-area carbon species. Moreover, the semi-closed architecture of derived carbons can effectively retard the polysulfides dissolution during charge/discharge, resulting in a capacity of 940 mAh g-1 after 120 charge/discharge cycles.

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

    Institute of Scientific and Technical Information of China (English)

    YE Hui; MA Jingming; FENG Chun; CHENG Ying; ZHU Suwen; CHENG Beijiu

    2009-01-01

    In the process of the fermentation of steroid C11α-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 2.08×1015 ions/cm2.with which the mutant strain AF-ANml6 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 difierences 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.

  20. BIOCONTROL OF ASPERGILLUS FLAVUS AND AFLATOXIN B1 PRODUCTION IN CORN

    OpenAIRE

    A. Khanafari, H. Soudi, M. Miraboulfathi

    2007-01-01

    The potent mycotoxin aflatoxin B1 is a secondary metabolite of Aspergillus fungi that grow, on a variety of food and feed commodities at any stage during growth, harvest, storage and transportation. The occurrence of aflatoxin contamination is global, with severe problems especially prevalent in developing countries. In present study, corn samples were contaminated with aflatoxin B1 in the concentration of 240 µg/kg. Four trials were inoculated by Lactobacillus plantarum (PTCC 1058). Three co...

  1. α--AMYLASES OF Aspergillus flavus var. oryzae AND Bacillus subtilis: THE SUBSTRATE SPECIFICITY AND RESISTANCE TO A NUMBER OF CHEMICALLY ACTIVE SUBSTANCES

    Directory of Open Access Journals (Sweden)

    K. V. Avdiyuk

    2013-06-01

    Full Text Available The ability of Aspergillus flavus var. oryzae 80428 and Bacillus subtilis 147 α-amylases to split different carbohydrate-containing substrates, such as maltose, sucrose, trehalose, dextrin, α- and β-cyclodextrin, amylose, amylopectin, glycogen, pullulan, soluble starch, insoluble starch, corn starch, wheat starch, dextran 500 has been studied. It was shown that investigated enzymes differ by substrate specificity. α-Amylase of A. flavus var. oryzae 80428 rapidly hydrolysed soluble potato and wheat starch, while the α-amylase of B. subtilis 147 — only wheat starch. Both enzymes don’t cleave maltose, α-cyclodextrin and dextran 500. A. flavus var. oryzae 80428 α-amylase display very small ability to hydrolyze pullulan, while α-amylase of B. subtilis 147 it does not act in general. The lowest values of Michaelis constant for both enzymes at splitting of glycogen have been obtained, indicating that enzymes have the greatest affinity to this substrate. The studies of influence of chemically active substances on activity of A. flavus var. oryzae 80428 and B. subtilis 147 ?-amylases show there are resistant to urea, deoxycholic acid, Tween-80, Triton X-100 and hydrogen peroxide. It’s indicate the enzymes tested may be competitive in compare with earlier described in literature enzymes. The obtained results give a possibility to propose in future usage these enzymes in different fields of industry, foremost in detergent industry.

  2. Effect of temperature and water activity on gene expression and aflatoxin biosynthesis in Aspergillus flavus on almond medium.

    Science.gov (United States)

    Gallo, Antonia; Solfrizzo, Michele; Epifani, Filomena; Panzarini, Giuseppe; Perrone, Giancarlo

    2016-01-18

    Almonds are among the commodities at risk of aflatoxin contamination by Aspergillus flavus. Temperature and water activity are the two key determinants in pre and post-harvest environments influencing both the rate of fungal spoilage and aflatoxin production. Varying the combination of these parameters can completely inhibit or fully activate the biosynthesis of aflatoxin, so it is fundamental to know which combinations can control or be conducive to aflatoxin contamination. Little information is available about the influence of these parameters on aflatoxin production on almonds. The objective of this study was to determine the influence of different combinations of temperature (20 °C, 28 °C, and 37 °C) and water activity (0.90, 0.93, 0.96, 0.99 aw) on growth, aflatoxin B1 (AFB1) production and expression of the two regulatory genes, aflR and aflS, and two structural genes, aflD and aflO, of the aflatoxin biosynthetic cluster in A. flavus grown on an almond medium solidified with agar. Maximum accumulation of fungal biomass and AFB1 production was obtained at 28 °C and 0.96 aw; no fungal growth and AFB1 production were observed at 20 °C at the driest tested conditions (0.90 and 0.93 aw). At 20° and 37 °C AFB1 production was 70-90% lower or completely suppressed, depending on aw. Reverse transcriptase quantitative PCR showed that the two regulatory genes (aflR and aflS) were highly expressed at maximum (28 °C) and minimum (20 °C and 37 °C) AFB1 production. Conversely the two structural genes (aflD and aflO) were highly expressed only at maximum AFB1 production (28 °C and 0.96-0.99 aw). It seems that temperature acts as a key factor influencing aflatoxin production which is strictly correlated to the induction of expression of structural biosynthesis genes (aflD and aflO), but not to that of aflatoxin regulatory genes (aflR and aflS), whose functional products are most likely subordinated to other regulatory processes acting at post-translational level

  3. Activity of the aqueous extract from Polymnia sonchifolia leaves on growth and production of aflatoxin B1 by Aspergillus flavus Atividade do extrato aquoso de folhas de Polymnia sonchifolia no crescimento e produção de aflatoxina B1 por Aspergillus flavus

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    Marina M. Pinto

    2001-06-01

    Full Text Available The aqueous extract from Polymnia sonchifolia leaves (AE was tested for inhibitory activity on aflatoxin B1(AFB1 production and growth of Aspergillus flavus. The cytotoxicity of AE on Vero cells was also performed. Suspensions of A. flavus spores were inoculated into 50 mL of YES medium together with different concentrations of the AE. The aflatoxin B1 was extracted, analyzed by thin layer chromatography and quantified by photodensitometry. All the concentrations of AE induced inhibition of AFB1 production. The aqueous extract showed in vitro cytotoxicity to Vero cells only at concentrations above 500 µg/mL.Neste trabalho verificou-se a atividade do extrato aquoso de folhas de Polymnia sonchifolia no crescimento e na produção de aflatoxinas B1 por Aspergillus flavus. Suspensões de esporos de A. flavus foram inoculadas em 50 mL de meio de YES com diferentes concentrações do extrato aquoso. A aflatoxina B1 foi extraída e analisada por cromatografia de camada delgada e quantificada por fotodensitometria. Todas as concentrações testadas inibiram a produção de aflatoxina B1. O extrato aquoso apresentou citotoxicidade em células Vero somente em concentrações acima de 500 µg/mL.

  4. Aspergillus flavus VelB acts distinctly from VeA in conidiation and may coordinate with FluG to modulate sclerotial production.

    Science.gov (United States)

    Chang, Perng-Kuang; Scharfenstein, Leslie L; Li, Ping; Ehrlich, Kenneth C

    2013-01-01

    The proteins VeA, VelB and LaeA of Aspergillus nidulans form a heterotrimeric complex (the velvet complex) in the dark to coordinate sexual development and production of some secondary metabolites. VeA and VelB of A. nidulans and Aspergillus fumigatus also are repressors of conidiation, but VeA of Aspergillus flavus in studied strains acts positively on conidiation. In the present study, we show via yeast-two hybrid assays that interactions among A. flavus VeA, VelB, and LaeA are conserved as in the A. nidulans velvet complex. We found that FluG, which is required for conidiophore formation in A. nidulans but whose deletion in A. flavus delays onset of conidiation, was probably an interacting partner of VelB. Deletion of velB in A. flavus CA14 severely impaired conidiation in the dark although to a lesser extent than deletion of veA. In both mutants fluG deletion resulted in further decreased conidiation even in the light. Deletion of fluG in the ΔlaeA strain, however, did not affect conidiation. All mutant types were unable to produce aflatoxin and sclerotia. Cross-complementation of the ΔvelB strain with gpdA::veA restored conidiation but not aflatoxin production although aflR, the aflatoxin pathway regulatory gene, was expressed at a normal level. Cross-complementation of the ΔveA strain with gpdA::velB failed to restore conidiation and aflatoxin production. The ΔvelB strain complemented with or a wild type transformed by gpdA::velB had elevated sclerotial production as the ΔfluG strain. Concerted interactions of A. flavus VeA and VelB with LaeA are critical for conidiation and aflatoxin biosynthesis. VelB may have a dual role and likely coordinates with FluG to modulate sclerotial production. PMID:23994319

  5. A study on trypsin, Aspergillus flavus and Bacillus sp. protease inhibitory activity in Cassia tora (L. syn Senna tora (L. Roxb. seed extract

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    Garg Satyendra K

    2011-07-01

    Full Text Available Abstract Background Proteases play an important role in virulence of many human, plant and insect pathogens. The proteinaceous protease inhibitors of plant origin have been reported widely from many plant species. The inhibitors may potentially be used for multiple therapeutic applications in viral, bacterial, fungal diseases and physiological disorders. In traditional Indian medicine system, Cassia tora (Senna tora is reportedly effective in treatment of skin and gastrointestinal disorders. The present study explores the protease inhibitory activity of the above plant seeds against trypsin, Aspergillus flavus and Bacillus sp. proteases. Methods The crushed seeds of Cassia tora were washed thoroughly with acetone and hexane for depigmentation and defatting. The proteins were fractionated by ammonium sulphate (0-30, 30-60, 60-90% followed by dialysis and size exclusion chromatography (SEC. The inhibitory potential of crude seed extract and most active dialyzed fraction against trypsin and proteases was established by spot test using unprocessed x-ray film and casein digestion methods, respectively. Electrophoretic analysis of most active fraction (30-60% and SEC elutes were carried employing Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE and Gelatin SDS-PAGE. Inhibition of fungal spore germination was studied in the presence of dialyzed active inhibitor fraction. Standard deviation (SD and ANOVA were employed as statistical tools. Results The crude seeds' extract displayed strong antitryptic, bacterial and fungal protease inhibitory activity on x-ray film. The seed protein fraction 30-60% was found most active for trypsin inhibition in caseinolytic assay (P Aspergillus flavus and Bacillus sp. proteases remained only 4, 7 and 3.1%, respectively when proteases were incubated with 3 mg ml-1 seed protein extract for 60 min. The inhibitory activity was evident in gelatin SDS-PAGE where a major band (~17-19 kD of protease

  6. Efficacy of Mentha spicata essential oil in suppression of Aspergillus flavus and aflatoxin contamination in chickpea with particular emphasis to mode of antifungal action.

    Science.gov (United States)

    Kedia, Akash; Dwivedy, Abhishek Kumar; Jha, Dhruva Kumar; Dubey, Nawal Kishore

    2016-05-01

    The present study reports in vivo antifungal and antiaflatoxigenic efficacy of Mentha spicata essential oil (EO) against toxigenic Aspergillus flavus strain LHP(C)-D6 in chickpea food system up to 12 months of storage. In addition, the mode of antifungal action of EO was also determined to understand the mechanism of fungal growth inhibition. The in vivo study with different concentrations of M. spicata EO showed dose-dependent decrease in fungal colony count as well as aflatoxin B1 concentration. The EO caused >50% protection in inoculated sets and >70% protection in uninoculated sets of chickpea food system against A. flavus at 1.0 μL mL(-1) air concentration. However, at the same concentration, EO caused 100% inhibition to aflatoxin B1 production in both sets when analyzed through high-performance liquid chromatography (HPLC). The antifungal target of EO in fumigated cells of A. flavus was found to be the plasma membrane when analyzed through electron microscopic observations and ions leakage test. The EO fumigated chickpea seeds showed 100% seed germination and seedling growth after 12 months of storage. Based on these observations, M. spicata EO can be recommended as plant-based preservative for safe protection of food commodities during storage conditions against fungal and most importantly mycotoxin contaminations. PMID:26338202

  7. The major volatile compound 2-phenylethanol from the biocontrol yeast, Pichia anomala, inhibits growth and expression of aflatoxin biosynthetic genes of Aspergillus flavus.

    Science.gov (United States)

    Hua, Sui Sheng T; Beck, John J; Sarreal, Siov Bouy L; Gee, Wai

    2014-05-01

    Aspergillus flavus is a ubiquitous saprophyte that is able to produce the most potent natural carcinogenic compound known as aflatoxin B1 (AFB1). This toxin frequently contaminates crops including corn, cotton, peanuts, and tree nuts causing substantial economic loss worldwide. Consequently, more than 100 countries have strict regulations limiting AFB1 in foodstuffs and feedstuffs. Plants and microbes are able to produce volatile compounds that act as a defense mechanism against other organisms. Pichia anomala strain WRL-076 is a biocontrol yeast currently being tested to reduce AF contamination of tree nuts in California. We used the SPME-GC/MS analysis and identified the major volatile compound produced by this strain to be 2-phenylethanol (2-PE). It inhibited spore germination and AF production of A. flavus. Inhibition of AF formation by 2-PE was correlated with significant down regulation of clustering AF biosynthesis genes as evidenced by several to greater than 10,000-fold decrease in gene expression. In a time-course analysis we found that 2-PE also altered the expression patterns of chromatin modifying genes, MYST1, MYST2, MYST3, gcn5, hdaA and rpdA. The biocontrol capacity of P. anomala can be attributed to the production of 2-PE, which affects spore germination, growth, toxin production, and gene expression in A. flavus. PMID:24504634

  8. Comparative moisture sorption, insect infestation and aflatoxin production by resident aspergillus flavus link spores in solar and sun dried cassava accessions before and after gamma irradiation

    International Nuclear Information System (INIS)

    Ten accessions of Solar and Sun dried cassava (Manihot esculenta Crantz) were studied for their comparative ability to absorb moisture and harbour insects under varying Environmental Relative Humidities, (ERH's) representative of the Ghanaian tropic conditions. The colour change during storage was also assessed by the Hunter's L * a* b* colour system. The production of aflatoxin (B1 B2, G1, and G2) before and after gamma irradiation (0, 20KGy) by resident Aspergillus flavus spores was also investigated. The moisture sorption isotherms of both solar and sun dried cassava flours followed a near sigmoid curve and equilibration at ERH's (55, 75, 95 %) was attained after 4-6 days at 32 degrees Celsius. The drying method did not significantly (P>0.01) influence the sorption isotherms. A gamma irradiation dose of at least 5KGy eliminated the infesting insects predominated by Araecerus fasciculatus and Lasioderma serricorne. Analysis of variance to determine the influence of incubation humidity (A) accession number (B) and radiation treatment (C) as well as the interaction of these factors showed that A, B, C significantly (P1. There was an apparent enhanced formation by A. flavus spores in the artificially inoculated cassava flour samples after irradiation with 20 KGy but this was not attributable to the irradiation treatment per se but rather to the tendency of reduced inoculum of A.flavus to produce more aflatoxins. (au)

  9. Inorganic composition determination and evaluation of the biological activity of Peperomia pellucida in the Aspergillus flavus growth; Estudo da composicao inorganica e avaliacao da atividade biologica de Peperomia pellucida no crescimento de Aspergillus flavus

    Energy Technology Data Exchange (ETDEWEB)

    Sussa, Fabio Vitorio

    2011-07-01

    oil, ethanolic and hexane extracts of Peperomia pellucida were tested for antifungal activity against Aspergillus flavus in vitro on Petri plates. The antifungal activity was based on the inhibition zone and IC{sub 50} values against the pathogen on Petri plates assays. Also, the essential oil chemical composition was determined by GC-MS. (author)

  10. Studies on the control of fungal contamination and aflatoxin production by Aspergillus flavus link in a cereal grain by the combination treatment of heat and irradiation

    International Nuclear Information System (INIS)

    Traditional storage of maize in tropical countries such as Ghana results in the rapid development of numerous fungi, including potential mycotoxin producers such as Aspergillus flavus (aflatoxins), A. ochraceus (ochratoxins, penicillic acid), Fusarium moniliforme (moniliformin), Paecilomyces varioti and Penicillium expansum (patulin). Treatment of maize with a combination of moist heat (30 min. at 600C and relative humidity > 85%) and gamma irradiation (4.0 kGy) proved to be effective in inactivating the resident population of fungal spores. This result was confirmed by in vitro studies with spores of Aspergillus flavus NRRL 5906. In a comparative study of packaging materials it was found that food commodities stored in woven polypropylene bags for six months at 85% R.H. had mould and yeast counts which were 2-3 log cycles lower than those of products kept in jute bags. Also, the viability of the seeds was better preserved in polypropylene sacks. It is recommended that the combination treatment be carried out on good quality grains, and that woven polypropylene sacks are used in packaging prior to irradiation, for maximum extension of shelf-life. (Auth.)

  11. Isolation of Aspergillus flavus from stored food commodities and Thymus vulgaris (L. essential oil used as a safe plant based preservative

    Directory of Open Access Journals (Sweden)

    Atul Kumar Singh

    2009-01-01

    Full Text Available Grain samples of Cicer arietinum (Chickpea, Zea mays (Maize, Cajanus cajan (Pigeon pea, Hordeum vulgare (Barley, Oryza sativa (Rice and Sorghum vulgare (Millet were procured from various retailers of market were subjected to their mould profile. During mycoflora analysis, 1297 fungal isolates were recorded from the food commodities. The least number of fungal isolates (189 were detected from H. vulgare while highest (244 from Z. mays. The genus Aspergillus was found to be most dominant encountered in all the samples, followed by Cladosporium cladosporoides, Alternaria alternata and Penicillium species. The highest percent relative density was recorded in case of Aspergillus flavus (36.24 followed by A. niger (28.45 and C. cladosporoides (10.95 while the lowest was found in case of Trichoderma viride (1.16. Some of the A. flavus isolates were toxigenic secreting aflatoxin B 1 . The survey reveals that the contamination of food commodities with storage fungi and mycotoxin is alarming and appropriate quality control measures should be taken urgently. The essential oil of Thymus vulgaris L. showed highest antifungal efficacy. The thyme oil absolutely inhibited the mycelial growth of A. flavus at 0.7µl ml -1 . The oil also showed significant antiaflatoxigenic efficacy as it completely arrested the aflatoxin B 1 production at 0.6µl ml -1 . Thyme oil as fungitoxicant was also found superior over most of the prevalent synthetic fungicides. The findings recommend the thyme oil as potential botanical preservative in eco-friendly control of biodeterioration of food commodities during storage.

  12. Suppression of Aflatoxin Biosynthesis in Aspergillus flavus by 2-Phenylethanol Is Associated with Stimulated Growth and Decreased Degradation of Branched-Chain Amino Acids.

    Science.gov (United States)

    Chang, Perng-Kuang; Hua, Sui Sheng T; Sarreal, Siov Bouy L; Li, Robert W

    2015-10-01

    The saprophytic soil fungus Aspergillus flavus infects crops and produces aflatoxin. Pichia anomala, which is a biocontrol yeast and produces the major volatile 2-phenylethanol (2-PE), is able to reduce growth of A. flavus and aflatoxin production when applied onto pistachio trees. High levels of 2-PE are lethal to A. flavus and other fungi. However, at low levels, the underlying mechanism of 2-PE to inhibit aflatoxin production remains unclear. In this study, we characterized the temporal transcriptome response of A. flavus to 2-PE at a subinhibitory level (1 μL/mL) using RNA-Seq technology and bioinformatics tools. The treatment during the entire 72 h experimental period resulted in 131 of the total A. flavus 13,485 genes to be significantly impacted, of which 82 genes exhibited decreased expression. They included those encoding conidiation proteins and involved in cyclopiazonic acid biosynthesis. All genes in the aflatoxin gene cluster were also significantly decreased during the first 48 h treatment. Gene Ontology (GO) analyses showed that biological processes with GO terms related to catabolism of propionate and branched-chain amino acids (valine, leucine and isoleucine) were significantly enriched in the down-regulated gene group, while those associated with ribosome biogenesis, translation, and biosynthesis of α-amino acids OPEN ACCESS Toxins 2015, 7 3888 were over-represented among the up-regulated genes. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that metabolic pathways negatively impacted among the down-regulated genes parallel to those active at 30 °C, a condition conducive to aflatoxin biosynthesis. In contrast, metabolic pathways positively related to the up-regulated gene group resembled those at 37 °C, which favors rapid fungal growth and is inhibitory to aflatoxin biosynthesis. The results showed that 2-PE at a low level stimulated active growth of A. flavus but concomitantly rendered decreased activities in

  13. Use of pyrosequencing to quantify incidence of a specific Aspergillus flavus strain within complex fungal communities associated with commercial cotton crops.

    Science.gov (United States)

    Das, Modan K; Ehrlich, Kenneth C; Cotty, Peter J

    2008-03-01

    Atoxigenic strains of Aspergillus flavus have been used as aflatoxin management tools on over 50,000 hectares of commercial crops since 2000. To assess treatment efficacy, atoxigenic strain incidence is routinely monitored by vegetative compatibility analyses (VCA) that require culturing, generation of auxotrophs, and complementation with tester mutants. Two pyrosequencing assays (PA) that require no culturing were developed for monitoring incidences of atoxigenic strains on ginned cottonseed. The assays, which quantify frequencies of characteristic single nucleotide polymorphisms (SNPs) in the aflR and pksA genes, were validated against standard VCA on cottonseed collected from commercial gins in South Texas, Arizona, and Southern California where the atoxigenic strain AF36 is used to manage aflatoxin contamination. Cottonseed washings were subjected to both VCA and PA. PA was performed directly on DNA isolated from particulates pelleted from the wash water by centrifugation. Addition of CaCl(2) and diatomaceous earth prior to pelleting increased the amount of DNA isolated. Accuracy and reproducibility of the PA were contrasted with those for the VCA that has been used for over a decade. Correlation coefficients between VCA and PA indicated good correspondence between the results from the two assays (r = 0.91 for aflR assay and r = 0.80 for pksA assay). PAs were highly variable for samples with low incidences of A. flavus due to variability in the initial polymerase chain reaction step. This held for both DNA isolated from cottonseed washes and for mixtures of purified DNA. For samples yielding low quantities of A. flavus DNA, averaging of results from 4 to 5 replicates was required to achieve acceptable correlations with VCA. Pyrosequencing has the potential to become a powerful tool for monitoring atoxigenic strains within complex A. flavus communities without limitations imposed by traditional culturing methods. PMID:18944078

  14. Inorganic composition determination and evaluation of the biological activity of Peperomia pellucida in the Aspergillus flavus growth

    International Nuclear Information System (INIS)

    Peperomia pellucida were tested for antifungal activity against Aspergillus flavus in vitro on Petri plates. The antifungal activity was based on the inhibition zone and IC50 values against the pathogen on Petri plates assays. Also, the essential oil chemical composition was determined by GC-MS. (author)

  15. Bioprocess and biotecnology: effect of xylanase from Aspergillus niger and Aspergillus flavus on pulp biobleaching and enzyme production using agroindustrial residues as substract.

    Science.gov (United States)

    de Alencar Guimaraes, Nelciele Cavalieri; Sorgatto, Michele; Peixoto-Nogueira, Simone de Carvalho; Betini, Jorge Henrique Almeida; Zanoelo, Fabiana Fonseca; Marques, Maria Rita; de Moraes Polizeli, Maria de Lourdes Teixeira; Giannesi, Giovana C

    2013-01-01

    This study compares two xylanases produced by filamentous fungi such as A. niger and A. flavus using agroindustrial residues as substract and evaluated the effect of these enzymes on cellulose pulp biobleaching process. Wheat bran was the best carbon source for xylanase production by A. niger and A. flavus. The production of xylanase was 18 and 21% higher on wheat bran when we compare the xylanase production with xylan. At 50°C, the xylanase of A. niger retained over 85% activity with 2 h of incubation, and A. flavus had a half-life of more than 75 minutes. At 55°C, the xylanase produced by A. niger showed more stable than from A. flavus showing a half-life of more than 45 minutes. The xylanase activity of A. niger and A. flavus were somehow protected in the presence of glycerol 5% when compared to the control (without additives). On the biobleaching assay it was observed that the xylanase from A. flavus was more effective in comparison to A. niger. The kappa efficiency corresponded to 36.32 and 25.93, respectively. That is important to emphasize that the cellulase activity was either analyzed and significant levels were not detected, which explain why the viscosity was not significantly modified. PMID:24010038

  16. Production of thermostable glucoamylase by newly isolated Aspergillus flavus A 1.1 and Thermomyces lanuginosus A 13.37 Produção e glucoamilase por Aspergillus flavus A1.1 e Thermomyces lanuginosus A13.37

    OpenAIRE

    Eleni Gomes; Simone Regina de Souza; Roseli Picolo Grandi; Roberto da Silva

    2005-01-01

    Thirteen thermophilic fungal strains were isolated from agricultural soil, tubers and compost samples in tropical Brazil. Two strains were selected based on of their ability to produce considerable glucoamylase activity while growing in liquid medium at 45ºC with starch as the only carbon source. They were identified as Aspergillus flavus A1.1 and Thermomyces lanuginosus A 13.37 Tsiklinsky. The experiment to evaluate the effect of carbon source, temperature and initial pH of the medium on enz...

  17. Bioprocess and biotecnology: effect of xylanase from Aspergillus niger and Aspergillus flavus on pulp biobleaching and enzyme production using agroindustrial residues as substract

    OpenAIRE

    de Alencar Guimaraes, Nelciele Cavalieri; Sorgatto, Michele; Peixoto-Nogueira, Simone de Carvalho; Betini, Jorge Henrique Almeida; Zanoelo, Fabiana Fonseca; Marques, Maria Rita; de Moraes Polizeli, Maria de Lourdes Teixeira; Giannesi, Giovana C

    2013-01-01

    This study compares two xylanases produced by filamentous fungi such as A. niger and A. flavus using agroindustrial residues as substract and evaluated the effect of these enzymes on cellulose pulp biobleaching process. Wheat bran was the best carbon source for xylanase production by A. niger and A. flavus. The production of xylanase was 18 and 21% higher on wheat bran when we compare the xylanase production with xylan. At 50°C, the xylanase of A. niger retained over 85% activity with 2 h of ...

  18. 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.

  19. A Public Platform for the Verification of the Phenotypic Effect of Candidate Genes for Resistance to Aflatoxin Accumulation and Aspergillus flavus Infection in Maize

    Directory of Open Access Journals (Sweden)

    Xueyan Shan

    2011-06-01

    Full Text Available A public candidate gene testing pipeline for resistance to aflatoxin accumulation or Aspergillus flavus infection in maize is presented here. The pipeline consists of steps for identifying, testing, and verifying the association of selected maize gene sequences with resistance under field conditions. Resources include a database of genetic and protein sequences associated with the reduction in aflatoxin contamination from previous studies; eight diverse inbred maize lines for polymorphism identification within any maize gene sequence; four Quantitative Trait Loci (QTL mapping populations and one association mapping panel, all phenotyped for aflatoxin accumulation resistance and associated phenotypes; and capacity for Insertion/Deletion (InDel and SNP genotyping in the population(s for mapping. To date, ten genes have been identified as possible candidate genes and put through the candidate gene testing pipeline, and results are presented here to demonstrate the utility of the pipeline.

  20. Occurrence of aflatoxins in mahua (Madhuca indica Gmel.) seeds: synergistic effect of plant extracts on inhibition of Aspergillus flavus growth and aflatoxin production.

    Science.gov (United States)

    Sidhu, O P; Chandra, Harish; Behl, H M

    2009-04-01

    Occurrence of aflatoxin in Madhuca indica Gmel. seeds was determined by competitive ELISA. Eighty percent of mahua seed samples were found to be contaminated with aflatoxin. Total aflatoxin content ranged from 115.35 to 400.54ppb whereas the concentration of AFB(1) was in the range of 86.43 to 382.45ppb. Mahua oil was extracted by cold press expeller and analysed for contamination of aflatoxin in both the oil and cake samples. Total aflatoxin and aflatoxin B(1) were 220.66 and 201.57ppb in oil as compared to that in cake samples where it was 87.55 and 74.35ppb, respectively. Various individual and combined plant extracts were evaluated for their efficacy against growth of Aspergillus flavus and aflatoxin production in vitro. Combination of botanicals were found to be more effective in controlling fungal growth and aflatoxin production than individual extracts. Results of the present study suggests that synergistic effect of plant extracts can be used for control of fungal growth and aflatoxin production. These natural plant products may successfully replace synthetic chemicals and provide an alternative method to protect mahua as well as other agricultural commodities of nutritional significance from toxigenic fungi such as A. flavus and aflatoxin production. PMID:19167450

  1. In vitro experimental environments lacking or containing soil disparately affect competition experiments of Aspergillus flavus and co-occurring fungi in maize grains.

    Science.gov (United States)

    Falade, Titilayo D O; Syed Mohdhamdan, Sharifah H; Sultanbawa, Yasmina; Fletcher, Mary T; Harvey, Jagger J W; Chaliha, Mridusmita; Fox, Glen P

    2016-07-01

    In vitro experimental environments are used to study interactions between microorganisms, and to predict dynamics in natural ecosystems. This study highlights that experimental in vitro environments should be selected to match closely the natural environment of interest during in vitro studies to strengthen extrapolations about aflatoxin production by Aspergillus and competing organisms. Fungal competition and aflatoxin accumulation were studied in soil, cotton wool or tube (water-only) environments, for Aspergillus flavus competition with Penicillium purpurogenum, Fusarium oxysporum or Sarocladium zeae within maize grains. Inoculated grains were incubated in each environment at two temperature regimes (25 and 30°C). Competition experiments showed interaction between the main effects of aflatoxin accumulation and the environment at 25°C, but not so at 30°C. However, competition experiments showed fungal populations were always interacting with their environments. Fungal survival differed after the 72-h incubation in different experimental environments. Whereas all fungi incubated within the soil environment survived, in the cotton wool environment none of the competitors of A. flavus survived at 30°C. With aflatoxin accumulation, F. oxysporum was the only fungus able to interdict aflatoxin production at both temperatures. This occurred only in the soil environment and fumonisins accumulated instead. Smallholder farmers in developing countries face serious mycotoxin contamination of their grains, and soil is a natural reservoir for the associated fungal propagules, and a drying and storage surface for grains on these farms. Studying fungal dynamics in the soil environment and other environments in vitro can provide insights into aflatoxin accumulation post-harvest. PMID:27264786

  2. Vitality Stains and Real Time PCR Studies to Delineate the Interactions of Pichia anomala and Aspergillus flavus

    Science.gov (United States)

    The objectives of this study were to probe the effect of the yeast, P. anomala against A flavus by using real time RT-PCR technique and vitality fluorescent stains. Yeast and fungi were inoculated into a 250 ml-flask containing 50 ml potato dextrose broth (PDB) at yeast to fungus (Y : F) ratios of ...

  3. Fungitoxic effect of natural extracts on mycelial growth, spore germination and aflatoxin B1 production of Aspergillus flavus

    OpenAIRE

    MOHAMMEDI, Zohra; ATIK, Fawzia

    2013-01-01

    The methanolic extracts of leaves from Tamarix aphylla, Tamarix pauciovulata, T. hirsuta, D. gnidium, C. procera, aerial parts from H. scoparium, A. schmittianum, P. argentea and M. canescens were investigated for their antifungal and antiaflatoxigenic activities against the aflatoxigenic fungus A. flavus. The results of antifungal activity evaluated by two methods indicate that three plant species (H. scoparium, A. schmittianun and D. gnidium) among the nine investigated showed s...

  4. Perfil bioquímico do soro de frangos de corte alimentados com dieta suplementada com alfa-amilase de Cryptococcus flavus e Aspergillus niger HM2003 Biochemichal serum profile of broilers fed diets suplemented with alfa-amylase from Cryptococcus flavus and Aspergillus niger HM2003

    Directory of Open Access Journals (Sweden)

    Cibele Silva Minafra

    2010-12-01

    Full Text Available Avaliou-se o perfil bioquímico do soro de frangos de corte alimentados com a enzima α-amilase produzida por dois microrganismos. Produziram-se dois extratos, um com a-amilase obtida a partir de Cryptococcus flavus em meio de levedura comercial e outro com Aspergillus niger HM2003 em meio de proteína de soja e amido comercial, com atividade de 9,58 U/mL e 10,0 U/mL, respectivamente. Utilizaram-se 360 pintos de corte Cobb 500 de 1 dia de idade e com 49,72 ± 0,68 g de peso vivo inicial. As aves foram alojadas em baterias e foram criadas até os 21 dias de idade. Foram utilizados três dietas, cada uma com cinco repetições de 12 aves, em delineamento inteiramente casualizado. A primeira dieta (basal foi formulada sem adição de enzima e as outras duas receberam a suplementação de a-amilase produzida por cultivo de Cryptococcus flavus e Aspergillus niger HM2003. Dietas à base de milho e soja foram formuladas em duas fases: pré-inicial (1-7 dias e inicial (8-21 dias. Na fase pré-inicial, foram observados os seguintes valores médios para cálcio (6,90 e 5,99 mg/dL, proteína plasmática (2,0 e 2,50 g/dL e fosfatase alcalina (979,98 e 974,66 UI/L, respectivamente para Cryptococcus flavus e Aspergillus niger HM2003. A dieta acrescida de a-amilase obtida a partir de Aspergillus niger HM2003 determinou maior concentração sérica de fósforo. Na fase inicial, os resultados significativos relacionaram-se a potássio quando avaliadas dietas com adição de a-amilase pelas duas fontes. A incorporação das enzimas testadas não proporciona alterações metabólicas ou toxicidade nos animais.It was evaluated the biochemical serum profile of broilers fed rations supplemented with α-amylase produced by two microorganisms. Two extracts were produced, one was produced with a-amylase obtained from Cryptococcus flavus in a commercial yeast-based medium and the other with Aspergillus niger HM2003 produced in soybean protein and commercial starch medium

  5. Genome Sequences of Eight Aspergillus flavus spp. and One A. parasiticus sp., Isolated from Peanut Seeds in Georgia.

    Science.gov (United States)

    Faustinelli, Paola C; Wang, Xinye Monica; Palencia, Edwin R; Arias, Renée S

    2016-01-01

    Aspergillus flavusandA. parasiticusfungi produce carcinogenic mycotoxins in peanut seeds, causing considerable impact on both human health and the economy. Here, we report nine genome sequences ofAspergillusspp., isolated from Georgia peanut seeds in 2014. The information obtained will lead to further biodiversity studies that are essential for developing control strategies. PMID:27081142

  6. Resistência de quatro genótipos de amendoim à produção de aflatoxina B1 após inoculação com Aspergillus flavus Link Resistance of aflatoxin B1 production by Aspergillus flavus Link its inoculation onto four peanuts genotypes

    Directory of Open Access Journals (Sweden)

    Guilherme PRADO

    1999-01-01

    Full Text Available Avaliou-se a produção de aflatoxina B1 pelo Aspergillus flavus IMI 190443, inoculado em sementes de genótipos de amendoim: Tatu Vermelho, VRR-245, 2117 e 2155, in natura e autoclavado a 1210 C por 20 minutos, previamente cultivados no Centro Experimental do Instituto Agronômico de Campinas, em 1995/96. A aflatoxina B1 foi quantificada por cromatografia em camada delgada, utilizando comparação visual com padrões. Os níveis de aflatoxina B1 das amostras autoclavadas e in natura dos genótipos Tatu Vermelho, VRR-245 e 2155 foram significativamente diferentes (p The levels of aflatoxin B1 in postharvest peanuts were evaluated after inoculation of seeds of four different genotypes : Tatu Vermelho, VRR-245, 2117 e 2155 with Aspergillus flavus IMI 190443. Field trials were conducted in 1995/96 at the Experimenal Center of the Instituto Agronômico de Campinas. The postharvest seeds were used in natura or autoclaved at 121 oC for 20 minutes prior to inoculation with the mold. The aflatoxin B1 was quantified by thin layer chromatography (TLC using a visual comparation with standards. The levels of aflatoxin B1 in autoclaved and in natura seeds were significantly different (p < 0,05 between the genotypes Tatu Vermelho, VRR-245, 2155 and the 2117. Samples of genotypes 2117, originating from India, presented the lowest levels of aflatoxin B1 irrespective of heating treatment or not, when compared with the others. The results show possibilities of doing explorations about the varietal resistance in the aflatoxin control.

  7. Metabolism of L-malic acid accumulation in Aspergillus flavus%黄曲霉积累L-苹果酸代谢机制初探

    Institute of Scientific and Technical Information of China (English)

    郝夕祥; 刘建军; 赵祥颖; 田延军; 张家祥

    2011-01-01

    L-malic acid is a member of tricarboxylic acid cycle (TCA cycle) in organism, which has widespread applications in food, medical, daily chemical industry, etc. The paper preliminary introduced the metabolic mechanism of L-malic acid in Aspergillus flavus from the aspects of limiting oxygen fermentation, the addition of calcium carbonate, the inhibitor of enzyme in the TCA cycle, glyoxylate cycle and so on. It was concluded that CO2 fixing pathway was the main route accumulating L-malic acid.%L-苹果酸是生物体内三羧酸循环的成员之一,在食品、医药、日用化工等部门具有广泛的用途.文中从限氧发酵、碳酸钙的添加量、乙醛酸循环和TCA循环相应酶的抑制剂几个方面初步探讨黄曲霉积累L-苹果酸的代谢机制,得出CO2固定途径是积累L-苹果酸的主要途径.

  8. Production of thermostable glucoamylase by newly isolated Aspergillus flavus A 1.1 and Thermomyces lanuginosus A 13.37 Produção e glucoamilase por Aspergillus flavus A1.1 e Thermomyces lanuginosus A13.37

    Directory of Open Access Journals (Sweden)

    Eleni Gomes

    2005-03-01

    Full Text Available Thirteen thermophilic fungal strains were isolated from agricultural soil, tubers and compost samples in tropical Brazil. Two strains were selected based on of their ability to produce considerable glucoamylase activity while growing in liquid medium at 45ºC with starch as the only carbon source. They were identified as Aspergillus flavus A1.1 and Thermomyces lanuginosus A 13.37 Tsiklinsky. The experiment to evaluate the effect of carbon source, temperature and initial pH of the medium on enzyme production was developed in a full factorial design (2x2x3. Enzyme productivity was influenced by the type of starch used as carbon source. Cassava starch showed to be a better substrate than corn starch for glucoamylase production by A. flavus but for T. lanuginosus the difference was not significant. Enzyme activities were determined using as substrates 0.3% soluble starch, 0.3% maltose or 0.3% of starch plus 0.1% maltose. The enzymes from A. flavus A1.1 hydrolyzed soluble starch preferentially but also exhibited a significant maltase activity. Moreover higher quantities of glucose were released when the substrate used was a mixture of starch and maltose, suggesting that this fungus produced two types of enzyme. In the case T. lanuginosus A 13.37, the substrate specificity test indicated that the enzyme released also hydrolyzed starch more efficiently than maltose, but there was no increase in the liberation of glucose when a mixture of starch and maltose was used as substrate, suggesting that only one type of enzyme was secreted. Glucoamylases produced from A. flavus A1.1 and T. lanuginous A.13-37 have high optimum temperature (65ºC and 70ºC and good thermostability in the absence of substrate (maintaining 50% of activity for 5 and 8 hours, respectively, at 60ºC and are stable over in a wide pH range. These new strains offer an attractive alternative source of enzymes for industrial starch processing.Entre 13 linhagens de fungos filamentosos

  9. Research of the inhibition activities effect of complex essential oil on Aspergillus flavus%复合精油对黄曲霉联合抑菌作用研究

    Institute of Scientific and Technical Information of China (English)

    曲春阳; 潘磊庆; 屠康; 杨立之

    2012-01-01

    The Diameter of Antibiotic Circle,Minimum Inhibition Concentration(MIC),Reduction Concentration(RC)and Fractional Inhibitory Concentration(FIC)of plant essential oils which used in single or combined were tested,and the fungicidal activities were evaluated by combined antiseptic evaluation method in order to find the best types and ratio of essential oils for inhibiting activities on Aspergillus flavus.The results indicated that garlic,cinnamon,clove and mint essential oils had strong inhibition activities on Aspergillus flavus.Combination of garlic and cinnamon essential oil showed surperimposed inhibition effects on Aspergillus flavus.The combined essential oil of garlic and cinnamon essential oil had the best inhibition effect on Aspergillus flavus when the volume ratio of them was 1:3.Therefore,this type of combined essential oil had a potential for the further applications as effective fungicidal components.%采用联合抑菌评价方法,通过测定植物精油抑菌圈直径、最低抑菌浓度(Minimum Inhibition Concentration,MIC)、最低生长下降浓度(Reduction Concentration,RC)、联合抑菌指数(Fractional Inhibitory Concentration,FIC),对植物精油单独及联合使用后的抑菌效果进行评价,筛选最佳抑制黄曲霉活性作用的复合精油种类及配比。结果表明:大蒜、肉桂、丁香、薄荷精油单独或复合使用均有较强抑制黄曲霉活性的作用。大蒜与肉桂精油联合抑菌评价为相加作用。当大蒜精油与肉桂精油复合体积比为1∶3时,复合精油具有最佳抑制黄曲霉活性的效果。因此,复合精油作为有效防霉保鲜成分具有良好的研发与应用前景。

  10. Biomassa, proteína, colesterol e glicose extracelular de cinco isolados de Aspergillus flavus - doi: 10.5102/ucs.v3i2.557

    OpenAIRE

    Wencerly Ramos Rodrigues Jr.; Tânia Cristina Andrade; Valdi Lopes Tutunji

    2008-01-01

    Fungos filamentosos são organismos importantes para a produção de enzimas, compostos químicos e farmacêuticos. O comportamento metabólico comparado dos fungos é importante para conhecer suas relações taxonômicas e seu potencial uso em microbiologia industrial. Cinco isolados de Aspergillus flavus foram analisados quanto à produção de biomassa, proteína total, colesterol e glicose em diferentes meios de cultura e temperatura. Poucas diferenças foram observadas. Alguns isolados foram capazes de...

  11. Improvement of the antifungal activity of Litsea cubeba vapor by using a helium-neon (He-Ne) laser against Aspergillus flavus on brown rice snack bars.

    Science.gov (United States)

    Suhem, Kitiya; Matan, Narumol; Matan, Nirundorn; Danworaphong, Sorasak; Aewsiri, Tanong

    2015-12-23

    The aim of this study was to improve the antifungal activity of the volatile Litsea cubeba essential oil and its main components (citral and limonene) on brown rice snack bars by applying He-Ne laser treatment. Different volumes (50-200 μL) of L. cubeba, citral or limonene were absorbed into a filter paper and placed inside an oven (18 L). Ten brown rice snack bars (2 cm wide × 4 cm long × 0.5 cm deep) were put in an oven and heated at 180 °C for 20 min. The shelf-life of the treated snack bars at 30 °C was assessed and sensory testing was carried out to investigate their consumer acceptability. A count of total phenolic content (TPC) and Fourier transform infrared spectroscopy (FTIR) on the properties of essential oil, citral, and limonene before and after the laser treatment was studied for possible modes of action. It was found that the laser treatment improved the antifungal activity of the examined volatile L. cubeba and citral with Aspergillus flavus inhibition by 80% in comparison with those of the control not treated with the laser. L. cubeba vapor at 100 μL with the laser treatment was found to completely inhibit the growth of natural molds on the snack bars for at least 25 days; however, without essential oil vapor and laser treatment, naturally contaminating mold was observed in 3 days. Results from the sensory tests showed that the panelists were unable to detect flavor and aroma differences between essential oil treatment and the control. Laser treatment caused an increase in TPC of citral oil whereas the TPC in limonene showed a decrease after the laser treatment. These situations could result from the changing peak of the aliphatic hydrocarbons that was revealed by the FTIR spectra. PMID:26433461

  12. 单离香料对黄曲霉的气相熏杀作用研究%Fungicidal Effect of Isolates on Aspergillus flavus by Fumigation

    Institute of Scientific and Technical Information of China (English)

    吴克刚; 林雅慧; 段雪娟; 柴向华; 赵欣欣

    2014-01-01

    为了开发潜在的植源性单离香料用于控制食品储藏过程中的霉变,采用平板熏蒸法和菌块转移法研究7种单离香料的杀菌作用。实验表明,单离香料对黄曲霉的杀菌作用依次为肉桂醛>百里香酚,水杨醛,柠檬醛>茴香脑>丁香酚,香兰素对黄曲霉基本没有作用。水杨醛、百里香酚、柠檬醛和肉桂醛的质量比为5:5:5:1时有显著的协同增效作用,最小杀菌体积分数为0.03125 mL/L。扫描电镜分析表明复合物使黄曲霉菌丝变薄、破裂、干枯,孢子收缩变形。复配香料影响黄曲霉的正常生理代谢,进一步导致抑制、杀灭作用。单离香料分子的活性中心为高电子云密度处,活性中心电子云密度高和空间位阻小,其杀菌效果更佳。%The fungicidal effects of seven natural isolates were evaluated by flat plate fumigation and block transfer methods. Results showed the fungicidal activity of isolates was in the order of cinnamaldehyde>thymol, salicylaldehyde, citral>anethole>eugenol. However, vanillin did not showed any fungicidal activity. The compound of salicylaldehyde, thymol, citral and cinnamaldehyde, in a ratio of 5:5:5:1, showed significant synergy effect, with the minimum fungicidal concentration ( MFC) of 0. 031 25 mL/L. SEM analysis showed that the isolate compound made the hypha of Aspergillus flavus become thinner, breakable and wizened, and the spores become shrunken and deformed. The compound affected the normal growth and metabolism of A. flavus, and led to fungistatic or fungicidal activity. The high electron density positions of isolate molecules were the active sites of fungicidal activity. More active sites with higher electron density and smaller steric hindrance resulted in the stronger fungicidal activity. The findings of the present study demonstrated the possible exploration of plants based isolates as safety preservatives against fungal spoilage during food stuffs

  13. Regulation of Development in Aspergillus nidulans and Aspergillus fumigatus

    OpenAIRE

    Yu, Jae-Hyuk

    2010-01-01

    Members of the genus Aspergillus are the most common fungi and all reproduce asexually by forming long chains of conidiospores (or conidia). The impact of various Aspergillus species on humans ranges from beneficial to harmful. For example, several species including Aspergillus oryzae and Aspergillus niger are used in industry for enzyme production and food processing. In contrast, Aspergillus flavus produce the most potent naturally present carcinogen aflatoxins, which contaminate various pl...

  14. Effect of gamma radiation on the growth of Aspergillus Flavus aflatoxins producer and on the use of polymerase chain reaction technique (PCR) in samples of maize grains artificially inoculated

    International Nuclear Information System (INIS)

    The aim of this present study was to verify the effects of gamma radiation on the growth of Aspergillus flavus Link aflatoxins producer; to demonstrate the application of Polymerase Chain Reaction (PCR) technique in the diagnostic of A. Flavus, as well to verify the effect of radiation in the profile of DNA bands. Twenty samples of grains maize with 200 g each were individually irradiated with 20 kGy, to eliminate the microbial contamination. In following, the samples were inoculated with an toxigenic A. flavus (1x106 spores/ml), incubated for 15 days at 25 deg C with a relative humidity of around 97,5% and irradiated with 0, 2; 5 and 10 kGy. The samples, 5 to each dose of irradiation, were individually analyzed for the number of fungal cells, water activity, viability test (fluorescein diacetate and ethidium bromide), PCR and aflatoxins (AFB) detection. The results showed that the doses used were effective in reducing the number of Colony Forming Units (CFU/g) mainly the doses of 5 and 10 kGy. In addition, the viability test showed a decrease of viable cells with increase of irradiation doses. The reduction of AFB1 and AFB-2, was more efficient with the use of 2 kGy in comparison with the dose of 5 kGy, while the dose of 10 kGy, degraded the aflatoxins. Thereby, it was observed that AFB2 showed to be more radiosensitive. The use of PCR technique showed the presence of DNA bands, in all samples. (author)

  15. 姜黄挥发油脂质体制备及其抗黄曲霉菌评价研究%Preparation of Turmeric Essential Oil Liposome and Research on Its Anti-Aspergillus flavus Efficacy

    Institute of Scientific and Technical Information of China (English)

    胡一晨; 孔维军; 杨美华

    2015-01-01

    目的:研究及评价姜黄挥发油的纳米脂质体系,以用于抑制黄曲霉菌生长及产毒,为纳米抗菌剂研究和开发奠定基础。方法:以安全性好的卵磷脂、胆固醇为膜材,采用乙醇注入结合超声乳化法,采用单因素考察与正交设计结合的方法优选姜黄挥发油脂质体制备工艺,并对所得脂质体进行理化表征和抗黄曲霉菌作用的评价。结果:采用卵磷脂与胆固醇比例10∶1,加药量与脂质比例1∶5,乙醇滴加速度1 mL/min,超声5 min,制备所得姜黄挥发油脂质体包封率、粒径分布、稳定性均较好。采用2 mL 脂质体/25 mL 培养基浓度,与黄曲霉菌共培养10 d,可完全抑制霉菌生长和黄曲霉毒素的产生。结论:将姜黄挥发油制备成纳米脂质体,既增加其体系稳定性和均一性,又保证了其抗黄曲霉菌性效,具有极大开发前景。%Objective:To develop the nano-liposomal system of turmeric essential oil for inhibiting Aspergillus flavus growth and aflatoxin generation.Methods:The stabilized and bio-safe liposomes loading turmeric essential oil were prepared by the ethanol injection-ultrasonic emulsification method with lecithin and cholesterol as excipients.Based on the combination of single factor screening and orthogonal design,liposomes were obtained by means of the optimized technology.Subsequently,following with the physicochemical characterization,the anti-Aspergillus flavus activity of liposomes were evaluated.Results:With the ratio of leci-thin and cholesterol(1 0∶1 ,weight ratio),ratio of feeding drug and excipient(1 :5,weight ratio),1 mL/min of the ethyl alcohol adding speed and along with ultrasonic emulsification for 5 min,liposomes were prepared,exhibiting high encapsulation efficiency, suitable size distribution,and good storage stability.Particularly,after incubation with 2 mL essential oil liposome per 25 mL cul-ture medium for 1 0d,almost 1 00% of

  16. Regulation of aflatoxin biosynthesis and branched-chain amino acids metabolism in Aspergillus flavus by 2-phenylethanol reveal biocontrol mechanism of Pichia anomala

    Science.gov (United States)

    Pichia anomala WRL-076 is a biocontrol yeast which has been shown to inhibit growth and aflatoxin production of A. flavus. Using the SPME-GC/MS analysis we identified that the volatile, 2-phenylethanol (2-PE) produced by this yeast and demonstrated that the compound inhibited aflatoxin production. W...

  17. 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...

  18. High incidence of Aspergillus flavus and aflatoxins in stored groundnut in Ghana and the use of a microbial assay to assess the inhibitory effects of plant extracts on aflatoxin synthesis.

    Science.gov (United States)

    Awuah, R T; Kpodo, K A

    1996-01-01

    Groundnut samples from 21 selected markets in the 10 regions of Ghana yielded high levels of the aflatoxigenic fungus Aspergillus flavus on half-strength potato dextrose agar. The fungus was associated with 31.7 and 12.8%, respectively, of all damaged and undamaged kernels assayed. Only 0.24% of total kernels assayed yielded A. parasiticus. Other fungi detected from total kernels assayed were A. niger (34%), A. candidus (1.45%), A. tamarii (3.93%), A. ochraceous (5.26%), Fusarium spp. (1.7%) Penicillium spp. (5.19%), a Mucor sp. (2.3%), a Trichoderma sp. (0.2%), Rhizopus stolonifer (12%) and certain unidentifiable fungi (11.72%). Total aflatoxin levels ranging from 5.7 to 22, 168 ppb were identified with damaged kernel samples. The mycotoxin was not detected in 50% of undamaged kernel samples tested and very low levels mostly ranging from 0.1 to 12.2 ppb were associated with the undamaged samples that tested positive for aflatoxins. In a novel in vitro microbial assay to determine the effectiveness of certain plant extracts against aflatoxin synthesis, extracts from Xylopia aethiopica, Monodera myristica, Cinnamomum verum and Piper nigrum permitted fungal growth in 1.5% potato-dextrose broth while completely suppressing NOR formation. These extracts, however, could not suppress NOR formation in a yeast extract sucrose medium. PMID:8981776

  19. Movilidad de Aspergillus flavus link ex fries en mazorcas de cinco genotipos de maiz (Zea Mays L. empleando tres métodos de inoculación (ING

    Directory of Open Access Journals (Sweden)

    Néstor Villalobos

    2016-03-01

    Full Text Available Three inoculation techniques for evaluating reaction of corn to kernel infection by Aspergillus flavus were tested in the field of five different genotypes. Inoculations were made 20 days after midsilk stage, using 0.5 ml of 105 conidial suspensions. The methods were: a injection of small amounts of inoculum in each kernel of a vertical row (M1; b injection in the first well developed kernels around the top part of the ear (M2; c injection of inoculum in the kernels at the lower part of the ear, forming a semicircle (M3. Two weeks after inoculation ears were harvested, and kernels not wounded were separated according to its position to the inoculated kernels, then surface sterilized and planted on PDA, to determine the infection percentage. M1 and M2 were found very efficient because they produced higher infection levels. M1 is considered the best because it provided a larger number of kernels for assay and was easy to use. No statistical difference was found among genotypes.

  20. Isolation of Aspergillus flavus from stored food commodities and Thymus vulgaris (L.) essential oil used as a safe plant based preservative

    OpenAIRE

    Atul Kumar Singh; Chandrabhan Seniya; Shriram Prasad

    2009-01-01

    Grain samples of Cicer arietinum (Chickpea), Zea mays (Maize), Cajanus cajan (Pigeon pea), Hordeum vulgare (Barley), Oryza sativa (Rice) and Sorghum vulgare (Millet) were procured from various retailers of market were subjected to their mould profile. During mycoflora analysis, 1297 fungal isolates were recorded from the food commodities. The least number of fungal isolates (189) were detected from H. vulgare while highest (244) from Z. mays. The genus Aspergillus was found to be most dominan...

  1. Impact of bacterial biocontrol agents on aflatoxin biosynthetic genes, aflD and aflR expression, and phenotypic aflatoxin B₁ production by Aspergillus flavus under different environmental and nutritional regimes.

    Science.gov (United States)

    Al-Saad, Labeed A; Al-Badran, Adnan I; Al-Jumayli, Sami A; Magan, Naresh; Rodríguez, Alicia

    2016-01-18

    The objectives of this study were to examine the efficacy of four bacterial antagonists against Aspergillus flavus using 50:50 ratio of bacterial cells/conidia for the control of aflatoxin B1 (AFB1) production on two different nutritional matrices, nutrient and maize-based media at different water availabilities (0.98, 0.94 water activity (aw) on nutrient medium; 0.995, 0.98 aw on maize meal agar medium) at 35°C. The indicators of efficacy used were the relative expression of one structural and regulatory gene in the biosynthetic pathway (aflD and aflR respectively) and the production of AFB1. These studies showed that some of the bacterial species could significantly inhibit the relative expression of the aflD and aflR genes at both 0.98 and 0.94 aw on nutrient agar. On maize-based media some of the bacterial antagonists reduced the activity of both genes at 0.94 aw and some at 0.995 aw. However, the results for AFB1 production were not consistent with the effects on gene expression. Some bacterial species stimulated AFB1 production on both nutrient and maize-based media regardless of aw. However, some bacterial treatments did inhibit AFB1 production significantly when compared to the control. Overall, this study suggests that temporal studies are required on the biosynthetic genes under different environmental and nutritional conditions to evaluate the potential of antagonists to control AFB1. PMID:26513252

  2. Bacillus subtilis脂肽Bacillomycin D抗黄曲霉毒素研究进展%Research Progress on the Inhibition Effect of Antimicrobial Lipopeptide Bacillomycin D from Bacil-lus subtilis on Aspergillus flavus

    Institute of Scientific and Technical Information of China (English)

    马芳芬; 殷海成

    2016-01-01

    枯草芽孢杆菌(Bacillus subtills)被认为是一种有效抑制黄曲霉并降解其毒素的菌种。己从不同的枯草芽孢杆菌菌株中分离得到具有抑制黄曲霉毒素的脂肽抗生素Bacillomycin D。Bacillomycin D属于Iturin家族,是枯草芽孢杆菌抑制黄曲霉毒素最强抗生素,也是目前唯一从枯草芽孢杆菌菌株中得到并且已经鉴定的具有抗黄曲霉活性的物质。该文对枯草芽孢杆菌及其抗菌脂肽Bacillomycin D的结构、性质、抑制黄曲霉机制进行了综述,为其进一步应用提供参考。%Bacillus subtilis is considered to be a probiotics,which can suppress the growth of Aspergillus flavus and degrade aflatoxin of the strain. So far,the lipopeptide complex like Bacillomycin D produced by the strain has been found have antifungal activities. Bacillomycin D belongs to the iturin family,which is the most powerful antibiotic for B.subtilis,and is currently the only material that has been identified from the strain.In this paper,the research ad⁃vances in chemical structure,physicochemical characters and antifungal properties of B. subtilis and/or bacillomycin D were reviewed to provide technical reference for the further research and application.

  3. 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...

  4. Aspergillus niger: an unusual cause of invasive pulmonary aspergillosis

    OpenAIRE

    Person, A. K.; Chudgar, S. M.; Norton, B. L.; Tong, B. C.; Stout, J E

    2010-01-01

    Infections due to Aspergillus species cause significant morbidity and mortality. Most are attributed to Aspergillus fumigatus, followed by Aspergillus flavus and Aspergillus terreus. Aspergillus niger is a mould that is rarely reported as a cause of pneumonia. A 72-year-old female with chronic obstructive pulmonary disease and temporal arteritis being treated with steroids long term presented with haemoptysis and pleuritic chest pain. Chest radiography revealed areas of heterogeneous consolid...

  5. Biocontrol of Aspergillus flavus by Pichia anomala

    Science.gov (United States)

    Aflatoxins are extremely potent natural carcinogens and a major food safety concern because of potential contamination of food commodities. Threshold levels set by the U. S. Food and Drug Administration for aflatoxins in foods for domestic consumption are less than 20 parts/ billion (ppb). However, ...

  6. 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. PMID:26658315

  7. Clonality and sex impact aflatoxigenicity in Aspergillus populations

    Science.gov (United States)

    Species in Aspergillus section Flavi commonly infect agricultural staples such as corn, peanuts, cottonseed, and tree nuts and produce an array of mycotoxins, the most potent of which are aflatoxins. Aspergillus flavus is the dominant aflatoxin-producing species in the majority of crops. Populatio...

  8. Extracellular xylanolytic and pectinolytic hydrolase production by A. flavus isolates contributes to crop invasion

    Science.gov (United States)

    Several atoxigenic Aspergillus flavus isolates, including some biocontrol agents, and one toxigenic isolate were surveyed for the ability to produce extracellular xylanolytic and pectinolytic hydrolases. All of the tested isolates displayed good production of endoxylanases when grown on a medium ut...

  9. Sporogenic Effect of Polyunsaturated Fatty Acids on Development of Aspergillus spp.

    OpenAIRE

    Calvo, Ana M.; Hinze, Lori L.; Gardner, Harold W.; Keller, Nancy P

    1999-01-01

    Aspergillus spp. are frequently occurring seed-colonizing fungi that complete their disease cycles through the development of asexual spores, which function as inocula, and through the formation of cleistothecia and sclerotia. We found that development of all three of these structures in Aspergillus nidulans, Aspergillus flavus, and Aspergillus parasiticus is affected by linoleic acid and light. The specific morphological effects of linoleic acid include induction of precocious and increased ...

  10. Two novel aflatoxin-producing Aspergillus species from Argentinean peanuts

    DEFF Research Database (Denmark)

    Pildain, M.B.; Frisvad, Jens Christian; Vaamonde, G.; Cabral, D.; Varga, J.; Samson, R.A.

    2008-01-01

    (morphology and extrolite profiles) and molecular (beta-tubulin and calmodulin gene sequences) characters. A. minisclerotigenes resembles Aspergillus flavus and Aspergillus parvisclerotigenus in producing aflatoxins B-1 and B-2, cyclopiazonic acid, kojic acid and aspergillic acid, but in addition it produces......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...... aflatoxins G(1) and G(2), aflavarins, aflatrem, aflavinines, parasiticolides and paspaline. This species also includes several isolates previously assigned to A. flavus group II and three Australian soil isolates. A. arachidicola produces aflatoxins B-1, B-2, G(1) and G(2), kojic acid, chrysogine and...

  11. Suppression of Aspergillus by Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Jensen, Britt Guillaume; Jelsbak, Lars; Søndergaard, Ib;

    suppressed growth of A. fumigatus, A. niger, A. flavus, A. oryzae, A. terreus and E. nidulans. HPLC and LC-DAD-MS results showed an increase in phenazine-1-carboxylic acid and phenazine-1-carboxamide production by P. aeruginosa in the contact area of Aspergillus. Different quinolones were also identified......, here among 2-heptyl-3-hydroxy-4-quinolone (PQS). An unidentified green pseudomonas compound was also observed. Interestingly the P. aeruginosa mutant rpoN was unable to suppress A. fumigatus, but suppressed A. flavus, A. oryzae and A. niger. However several other P. aeruginosa mutants suppressed A...

  12. 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.

  13. In Vitro Interactions between Target of Rapamycin Kinase Inhibitor and Antifungal Agents against Aspergillus Species.

    Science.gov (United States)

    Gao, Lujuan; Ding, Xiaozhen; Liu, Zhun; Wu, Qingzhi; Zeng, Tongxiang; Sun, Yi

    2016-06-01

    In vitro interactions of INK128, a target of rapamycin (TOR) kinase inhibitor, and antifungals, including itraconazole, voriconazole, posaconazole, amphotericin B, and caspofungin, against Aspergillus spp. were assessed with the broth microdilution checkerboard technique. Our results suggested synergistic effects between INK128 and all azoles tested, against multiple Aspergillus fumigatus and Aspergillus flavus isolates. However, no synergistic effects were observed when INK128 was combined with amphotericin B or caspofungin. No antagonism was observed for any combination. PMID:26976874

  14. Investigation of Malic Acid Production in Aspergillus oryzae under Nitrogen Starvation Conditions

    OpenAIRE

    Knuf, C.; Nookaew, I.; Brown, S H; McCulloch, M.; BERRY, A.; Nielsen, J.

    2013-01-01

    Malic acid has great potential for replacing petrochemical building blocks in the future. For this application, high yields, rates, and titers are essential in order to sustain a viable biotechnological production process. Natural high-capacity malic acid producers like the malic acid producer Aspergillus flavus have so far been disqualified because of special growth requirements or the production of mycotoxins. As A. oryzae is a very close relative or even an ecotype of A. flavus, it is like...

  15. Genomic sequences of Aspergillus flavus accessions in Georgia USA

    Data.gov (United States)

    US Agency for International Development — The data was produced as part of the Feed the Future Innovation Lab for Collaborative Research on Peanut Productivity and Aflatoxin Control (the Peanut &...

  16. Biodiversity of Aspergillus Section Flavi in Europe in relation to the management of aflatoxin risk

    OpenAIRE

    GiancarloPerrone; AntoniaGallo

    2014-01-01

    Aflatoxins and the producing fungi Aspergillus Section Flavi are widely known as the most serious and dangerous mycotoxin issue in agricultural products. In Europe, before the outbreak of aflatoxins on maize (2003-2004) due to new climatic conditions, their contamination was confined to imported foods. Little information is available on molecular biodiversity and population structure of Aspergillus Section Flavi in Europe. Preliminary reports evidenced the massive presence of A. flavus L-morp...

  17. Aflatoxin B1-producing Aspergillus in sun-dried medicinal plant materials

    OpenAIRE

    Chinaputi, A.; Lim, S; Petcharat, V.; Chuenchit, S.; Pathanadech, A.

    2001-01-01

    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 isola...

  18. GAMBARAN CEMARAN JAMUR, JAMUR Aspergillus jlavus DAN AFLATOKSIN PADA SIMPLISIA DARI PABRIK JAMU DI PULAU JAWA

    Directory of Open Access Journals (Sweden)

    Ani Isnawati

    2012-10-01

    Full Text Available Bahan baku obat tradisional (simplisia umumnya berasal dari alam terutama bahan tumbuh­ tumbuhan atau bagian tumbuhan. Bahan-bahan tersebut dapat terkontaminasi mikroba selama penanaman, pengeringan, penyimpanan, sehingga dapat mencemari simplisia. Keadaan lingkungan dan iklim Indonesia sangat menunjang perkembangan jamur dan pembentukan ajlatoksin. Sehingga untuk mengetahui berapa besar cemaran jamur,  jamur Aspergillus flavus dan ajlatoksin pada simplisia, maka dilakukan penelitian mengenai "Gambaran Cemaran Jamur, Jamur A. flavus dan ajlatoksin Pada Simplisia" Penelitian dilakukan terhadap 5 jenis simplisia yang diambil secara purposive dari 5 pabrik di Jakarta dan sekitarnya, 5 pabrik di Jawa Tengah dan 5 pabrik di Jawa Timur. Pemeriksaan angka kapang, jamur A.flavus ditetapkan secara mikrobiologi sedangkan penetapan ajlatoksin ditetapkan secara KLT (kromatografi Lapis Tipis . Hasil penelitian angka kapang menunjukkan bahwa jumlah Kencur, Adas dan Jung rahab masing­-masing 33,33% tidak memenuhi batas persyaratan Kepmenkes No.661/MENKES/SK/VII/1994, sedangkan Laos 22.22% serta Sembung 11,11%. A. jlavus ditemukan pada Adas 77,77% dengan positif ajlatoksin B2 55,55%, pada Kencur ditemukan A. flavus 33,33% dijumpai positif ajlatoksin B1 11,11%, dan pada Laos, Jung Rahab serta Sembung ditemukan A. flavus masing-masing  11,11%. Jung rahab positif ajlatoksin B1 11,11%. Sembung tidak positif ajlatoksin.   Kata  kunci: Kencur, Laos,  Adas, Jung  rahab, Sembung, Jamur, Aspergillus flavus, ajlatoksin

  19. The activity of galanga (Alpinia galanga) rhizome extract against the growth of filamentous fungi Aspergillus spp. that produce aflatoxin and Fusarium moniliforme

    OpenAIRE

    NOOR SOESANTI HANDAJANI; TJAHJADI PURWOKO

    2008-01-01

    Galanga (Alpinia galanga L.) rhizome was known to inhibit the growth of pathogenic fungi. The antifungal substances of galangal rhizome were found from their volatile oil. The objectives of this experiment were to study the ethanol extract of galangal rhizome against the growth of filamentous fungi Fusarium moniliforme, Aspergillus flavus, Aspergillus terreus, and Aspergillus niger that produce mycotoxin, especially aflatoxin, based on biomass and colony area and to determinate minimum growth...

  20. Aspergillus triggers phenazine production in Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Jensen, Britt Guillaume; Jelsbak, Lars; Søndergaard, Ib;

    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...... 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...... comparing with or without the presence of Pseudomonas. Conclusion: All Aspergilli tested, with the exception of A. fumigatus, triggered the upregulation of phenazine-1-carboxamide and phenazine-1-carboxylic acid production by P. aeruginosa. Surprisingly no changes in secondary metabolite profiles were...

  1. Negative regulation and developmental competence in Aspergillus.

    Science.gov (United States)

    Lee, Mi-Kyung; Kwon, Nak-Jung; Lee, Im-Soon; Jung, Seunho; Kim, Sun-Chang; Yu, Jae-Hyuk

    2016-01-01

    Asexual development (conidiation) in the filamentous fungus Aspergillus nidulans is governed by orchestrated gene expression. The three key negative regulators of conidiation SfgA, VosA, and NsdD act at different control point in the developmental genetic cascade. Here, we have revealed that NsdD is a key repressor affecting the quantity of asexual spores in Aspergillus. Moreover, nullifying both nsdD and vosA results in abundant formation of the development specific structure conidiophores even at 12 h of liquid culture, and near constitutive activation of conidiation, indicating that acquisition of developmental competence involves the removal of negative regulation exerted by both NsdD and VosA. NsdD's role in repressing conidiation is conserved in other aspergilli, as deleting nsdD causes enhanced and precocious activation of conidiation in Aspergillus fumigatus or Aspergillus flavus. In vivo NsdD-DNA interaction analyses identify three NsdD binding regions in the promoter of the essential activator of conidiation brlA, indicating a direct repressive role of NsdD in conidiation. Importantly, loss of flbC or flbD encoding upstream activators of brlA in the absence of nsdD results in delayed activation of brlA, suggesting distinct positive roles of FlbC and FlbD in conidiation. A genetic model depicting regulation of conidiation in A. nidulans is presented. PMID:27364479

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

    Directory of Open Access Journals (Sweden)

    Kim-Chung Lee

    2015-06-01

    Full Text Available 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-(sulfooxybenzoic acid and (sulfooxybenzoic acid, may possess anti-inflammatory properties, as 2-(sulfooxybenzoic acid possesses a structure similar to those of aspirin [2-(acetoxybenzoic 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-(sulfooxybenzoic acid and (sulfooxybenzoic acid are virulent factors of the pathogenic Aspergillus species.

  3. EFFECT OF TREATMENT WITH MOLD INHIBITORS ON PLANT GROWTH OF CORN AND SOME NUTRITIONAL COMPONENTS OF STORED GRAINS, INFECTED WITH A. FLAVUS AND F. VERTICILLOIDES

    Directory of Open Access Journals (Sweden)

    Mervat S. Youssef

    2012-12-01

    Full Text Available Planting sterilized corn grains in soil, treated with the mold inhibitors Fix-a-tox (FAT or Antitox Plus (AP resulted, in cases, in dwarfed and malformed corn plants and in the development of deformed, bone-shaped and grain-free corn cobs. Moreover, treating corn grains with the mold inhibitors before storage for one month caused significant changes in some nutritional components of corn grains, i.e. proteins, aminoacids, crude fibers, moisture, fats, ash and carbohydrates. Insignificant differences in protein percetage were detected between control inoculated with Aspergillus flavus and those treated with butyl hydroxyanisole (BHA antioxidant or FAT treatments, whereas ground clove significantly reduced protein content. In corn grains inoculated with Fusariumverticillioides, previous treatment with FAT resulted in significant reduction in the content of proline, aspartic acid, cysteine, valine, isoleucine and leucine, whereas treatment with BHA significantly reduced the content of threonine, serine, glutamic, glycine, alanine, phenylalanine and tyrosine. In Aspergillus flavus treatments, FAT significantly increased the content of methionine and threonine, whereas, aspartic acid showed 26 percentage decreases, compared to the control. Pronounced reductions in threonine, isoleucine and leucine were also detected in corn grains treated with BHA. Significant increases in fiber content were detected in inoculated corn grains treated with BHA, attaining 1.34 to 2.05-fold over that of control, respectively. Treatment with FAT and BHA led to pronounced reductions in moisture content in corn inoculated with both F. verticilloides and A. flavus trials. However, treatment with ground clove significantly increased the moisture content in A. flavus treatment. FAT treatment led to significant increase in ash and fat contents in both A. flavus and F. verticilloides treatments, whereas the other tested treatments of F. verticilloides significantly

  4. Isolation of Aspergillus species from Nasal Cavity and Bedroom of Healthy Volunteers and Patients with Allergic Rhinitis in Mashhad, Iran

    Directory of Open Access Journals (Sweden)

    Samaneh Eidi

    2014-12-01

    Full Text Available Background: The purpose of this study was to investigate the presence, frequency and comparison of Aspergillus spp. in nasal cavity and bedroom of healthy volunteers and patients with allergic rhinitis. Materials and Methods: In this cross-sectional study, a group of patients with allergic rhinitis (N=50 were selected based on positive skin prick test. Healthy volunteers were chosen to be in the comparison group by matching in age, gender, and no history of respiratory system disease. Samples from nasal cavity and different parts of bedroom were collected and cultured. Cultured Aspergillus spp. was identified by standard mycological techniques. Results: The most common species isolated from all samples of healthy volunteers was A. flavus (88%, followed by A. niger (76% and A. fumigatus (74%. A. flavus (56% was the predominant species isolated from all samples of patients, followed by A. niger (34% and A. fumigatus (6%. Conclusion: A. flavus was the most prevalent species of Aspergillus both healthy volunteers and patients. The presence of Aspergillus in homes does not necessarily imply a cause and effect relationship with illness, but we speculate that A. flavus may be a major source of aeroallergens along with A. niger and A. fumigatus; and should alert physicians and healthcare professionals to do more vigorous environmental testing.

  5. Distribution of aflatoxigenic Aspergillus section Flavi in commercial poultry feed in Nigeria.

    Science.gov (United States)

    Ezekiel, C N; Atehnkeng, J; Odebode, A C; Bandyopadhyay, R

    2014-10-17

    The distribution and aflatoxigenicity of Aspergillus section Flavi isolates in 58 commercial poultry feed samples obtained from 17 states in five agro-ecological zones (AEZs) in Nigeria were determined in order to assess the safety of the feeds with respect to aflatoxin-producing fungi. Correlation was also performed for incidence of species, aflatoxin-producing ability of isolates in vitro, and aflatoxin (AFB1) concentrations in the feed. A total of 1006 Aspergillus section Flavi isolates were obtained from 87.9% of the feed samples and identified as Aspergillus flavus, unnamed taxon SBG, Aspergillus parasiticus and Aspergillus tamarii. A. flavus was the most prevalent (91.8%) of the isolates obtained from the feed in the AEZs while A. parasiticus had the lowest incidence (0.1%) and was isolated only from a layer mash sample collected from the DS zone. About 29% of the Aspergillus isolates produced aflatoxins in maize grains at concentrations up to 440,500μg/kg B and 341,000μg/kgG aflatoxins. The incidence of toxigenic isolates was highest (44.4%) in chick mash and lowest (19.9%) in grower mash. The population of A. flavus in the feed had positive (r=0.50) but non significant (p>0.05) correlations with proportion of toxigenic isolates obtained from the feed while SBG had significant (pfeed. Poultry feed in Nigerian markets are therefore highly contaminated with aflatoxigenic Aspergillus species and consequently, aflatoxins. This is a potential threat to the poultry industry and requires urgent intervention. PMID:25108761

  6. Characterization of filamentous fungi isolated from Moroccan olive and olive cake: toxinogenic potential of Aspergillus strains.

    Science.gov (United States)

    Roussos, Sevastianos; Zaouia, Nabila; Salih, Ghislane; Tantaoui-Elaraki, Abdelrhafour; Lamrani, Khadija; Cheheb, Mostafa; Hassouni, Hicham; Verhé, Fréderic; Perraud-Gaime, Isabelle; Augur, Christopher; Ismaili-Alaoui, Mustapha

    2006-05-01

    During the 2003 and 2004 olive oil production campaigns in Morocco, 136 samples from spoiled olive and olive cake were analyzed and 285 strains were isolated in pure culture. Strains included 167 mesophilic strains belonging to ten genera: Penicillium, Aspergillus, Geotrichum, Mucor, Rhizopus, Trichoderma, Alternaria, Acremonium, Humicola, Ulocladium as well as 118 thermophilic strains isolated in 2003 and 2004, mainly belonging to six species: Aspergillus fumigatus, Paecilomyces variotii, Mucor pusillus, Thermomyces lanuginosus, Humicola grisea, and Thermoascus aurantiacus. Penicillium and Aspergillus, respectively, 32.3 and 26.9% of total isolates represented the majority of mesophilic fungi isolated. When considering total strains (including thermotolerant strains) Aspergillus were the predominant strains isolated; follow-up studies on mycotoxins therefore focused primarily on aflatoxins (AFs) and ochratoxin A (OTA) from the latter strains. All isolated Aspergillus flavus strains (9) and Aspergillus niger strains (36) were studied in order to evaluate their capacity to produce AFs and OTA, respectively, when grown on starch-based culture media. Seven of the nine tested A. flavus strains isolated from olive and olive cake produced AF B1 at concentrations between 48 and 95 microg/kg of dry rice weight. As for the A. niger strains, 27 of the 36 strains produced OTA. PMID:16715545

  7. Effect of serum components on biofilm formation by Aspergillus fumigatus and other Aspergillus species.

    Science.gov (United States)

    Wuren, Tuya; Toyotome, Takahito; Yamaguchi, Masashi; Takahashi-Nakaguchi, Azusa; Muraosa, Yasunori; Yahiro, Maki; Wang, Dan-Ni; Watanabe, Akira; Taguchi, Hideaki; Kamei, Katsuhiko

    2014-01-01

    Biofilm production by microorganisms is critical for their pathogenicity. Serum promotes biofilm production by Aspergillus fumigatus; however, its effects on other Aspergillus spp. have not been reported. We analyzed biofilm formation by five Aspergillus spp., i.e., A. fumigatus, A. flavus, A. nidulans, A. niger, and A. terreus, and examined the effects of serum/serum proteins such as fetal bovine serum (FBS), fetuin A, and bovine serum albumin (BSA) on hyphal growth, hyphal branching, and extracellular matrix (ECM) formation. The antifungal susceptibility of A. fumigatus isolates that formed biofilms was also examined. All serum/serum proteins promoted the growth of all these fungal species; growth promotion was most evident with FBS, followed by fetuin A and BSA. This effect was most evident in case of A. fumigatus and least evident in case of A. terreus. Electron microscopy showed thick ECM layers surrounding fungal cell walls after culture with FBS, particularly in A. fumigatus. An increase in hyphal branching caused by fetuin A was the highest in case of A. fumigatus and A. nidulans. Biofilm-forming A. fumigatus showed resistance to most antifungal agents, although a synergism of micafungin and amphotericin B was suggested. Our results indicate that serum promotes biofilm formation, including thick ECM, by many Aspergillus spp., particularly A. fumigatus, and that this may be closely related to its virulence. PMID:24858605

  8. Share of aflatoxigenic moulds from genera Aspergillus and Penicillium in mycopopulations isolated from spices for meat processing industry

    Directory of Open Access Journals (Sweden)

    Šarić Ljubiša Ć.

    2008-01-01

    Full Text Available Results of this paper show share of aflatoxigenic moulds from genera Aspergillus and Penicillium in mycopopulations isolated from spices that are often used in meat processing (ground pepper, dried peppercorn, paprika powder, caraway and laurel. Using standard mycological methods, it has been found that all the examined samples were contaminated by Aspergillus species, and further 50% by Penicillium species. Additionally, aflatoxigenic moulds A. flavus and A. niger were found to be present. A. flavus was present with 60% in the samples of dried peppercorn 2; paprika powder 2, while its frequencies in ground pepper 1 and laurel were 50% and 28,5%. respectively. A. niger made up 50% of all the isolates of Aspergillus and Penicillium species, isolated from paprika powder 1, although its share in the samples of laurel, paprika powder 2 and ground pepper 1 was 43%, 20% and 10% respectively.

  9. Adenomas hipofisários produtores de ACTH: Aspectos neurocirúrgicos

    Directory of Open Access Journals (Sweden)

    Tella Jr Oswaldo Inácio

    2002-01-01

    Full Text Available Relatamos nossa experiência com 19 casos de adenomas hipofisários produtores de ACTH que foram tratados cirurgicamente. Os adenomas mono hormonais produtores de ACTH eram microadenomas em 50% dos casos, apresentando-se com o quadro típico da síndrome de Cushing. Os pluri-hormonais manifestaram-se por alterações visuais. O resultado do tratamento cirúrgico, geralmente por via transeptoesfenoidal, foi satisfatório na maioria dos casos. Para os pacientes em que não conseguimos cura cirúrgica, foi indicada a radioterapia.

  10. Bioleaching of serpentine group mineral by fungus Talaromyces flavus: application for mineral carbonation

    Science.gov (United States)

    Li, Z.; Lianwen, L.; Zhao, L.; Teng, H.

    2011-12-01

    Many studies of serpentine group mineral dissolution for mineral carbonation have been published in recent years. However, most of them focus mainly on either physical and chemical processes or on bacterial function, rather than fungal involvement in the bioleaching of serpentine group mineral. Due to the excessive costs of the magnesium dissolution process, finding a lower energy consumption method will be meaningful. A fungal strain Talaromyces flavus was isolated from serpentinic rock of Donghai (China). No study of its bioleaching ability is currently available. It is thus of great significance to explore the impact of T. flavus on the dissolution of serpentine group mineral. Serpentine rock-inhabiting fungi belonging to Acremonium, Alternaria, Aspergillus, Botryotinia, Cladosporium, Clavicipitaceae, Cosmospora, Fusarium, Monascus, Paecilomyces, Penicillium, Talaromyces, Trichoderma were isolated. These strains were chosen on the basis of resistance to magnesium and nickel characterized in terms of minimum inhibiting concentration (MIC). Specifically, the strain Talaromyces flavus has a high tolerance to both magnesium (1 mol/L) and nickel (10 mM/L), and we examine its bioleaching ability on serpentine group mineral. Contact and separation experiments (cut-off 8 000-14 000 Da), as well as three control experiments, were set up for 30 days. At least three repeated tests were performed for each individual experiment. The results of our experiments demonstrate that the bioleaching ability of T. flavus towards serpentine group mineral is evident. 39.39 wt% of magnesium was extracted from lizardite during the bioleaching period in the contact experiment, which showed a dissolution rate at about a constant 0.126 mM/d before reaching equilibrium in 13 days. The amount of solubilized Mg from chrysotile and antigorite were respectively 37.79 wt% and 29.78 wt% in the contact experiment. These results make clear the influence of mineral structure on mineral bioleaching

  11. Requirement of Monooxygenase-Mediated Steps for Sterigmatocystin Biosynthesis by Aspergillus nidulans

    OpenAIRE

    Keller, Nancy P.; Watanabe, Coran M. H.; Kelkar, Hemant S.; Adams, Thomas H; Townsend, Craig A.

    2000-01-01

    Sterigmatocystin (ST) and aflatoxin B1 (AFB1) are two polyketide-derived Aspergillus mycotoxins synthesized by functionally identical sets of enzymes. ST, the compound produced by Aspergillus nidulans, is a late intermediate in the AFB1 pathway of A. parasiticus and A. flavus. Previous biochemical studies predicted that five oxygenase steps are required for the formation of ST. A 60-kb ST gene cluster in A. nidulans contains five genes, stcB, stcF, stcL, stcS, and stcW, encoding putative mono...

  12. Biodiversity of Aspergillus species in some important agricultural products

    DEFF Research Database (Denmark)

    Perrone, Giancarlo; Susca, A.,; Cozzi, G.;

    2007-01-01

    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...

  13. Inhibition of Aspergillus growth and aflatoxin release by derivatives of benzoic acid.

    OpenAIRE

    Chipley, J. R.; Uraih, N

    1980-01-01

    A study was conducted to determine the effects of o-nitrobenzoate, p-aminobenzoate, benzocaine (ethyl aminobenzoate), ethyl benzoate, methyl benzoate, salicylic acid (o-hydroxybenzoate), trans-cinnamic acid (beta-phenylacrylic acid), trans-cinnamaldehyde (3-phenylpropenal), ferulic acid (p-hydroxy-3-methoxycinnamic acid), aspirin (o-acetoxy benzoic acid), and anthranilic acid (o-aminobenzoic acid) upon growth and aflatoxin release in Aspergillus flavus NRRL 3145 and A. parasiticus NRRL 3240. ...

  14. Impact of environmental and plant factors on Aspergillus section Flavi isolated from maize in Italy

    OpenAIRE

    Giorni, Paola

    2007-01-01

    The exceptional hot weather conditions in Italy during the summer of 2003 resulted in an optimal environment for the development of Aspergillus section Flavi in maize and, consequently, for aflatoxin production. This caused significant contamination, above the EU legal limits, for maize destined to feed and food. This study was focused to define the distribution of these fungi in Italy for the first time. In all the sampled regions of Northern Italy, A. flavus was present. ...

  15. Morphological Transitions Governed by Density Dependence and Lipoxygenase Activity in Aspergillus flavus▿ †

    OpenAIRE

    Horowitz Brown, S.; Zarnowski, R.; Sharpee, W. C.; Keller, N P

    2008-01-01

    Aspergillus flavus differentiates to produce asexual dispersing spores (conidia) or overwintering survival structures called sclerotia. Results described here show that these two processes are oppositely regulated by density-dependent mechanisms and that increasing the cell density (from 101 to 107 cells/plate) results in the lowest numbers of sclerotial and the highest numbers of conidial. Extract from spent medium of low-cell-density cultures induced a high-sclerotium-number phenotype, wher...

  16. Antifungal activity of ibuprofen against aspergillus species and its interaction with common antifungal drugs

    Institute of Scientific and Technical Information of China (English)

    LI Li-juan; CHEN Wei; XU Hui; WAN Zhe; LI Ruo-yu; LIU Wei

    2010-01-01

    Background The incidence of invasive aspergillosis (IA) has increased in frequency in immunocompromised patients with a variety of diseases. The poor prognosis might be due to limited treatment option. This study aimed to evaluate antifungal activity of ibuprofen against clinical isolates of aspergillus species, as well as its interaction with azoles or with amphotericin B or with micafungin.Methods Antifungal activity of ibuprofen against 10 strains of Aspergillus fumigatus, Aspergillus flavus, and Aspergillus terreus were tested with both disk diffusion assay and standard broth microdilution method. To determine whether ibuprofen combined with itraconazole, voriconazole, amphotericin B, or micafungin had interactive effects on aspergillus spp., we used both disk diffusion assay and Chequerboard method.Results As for disk diffusion method, ibuprofen produced a zone of growth inhibition with diameters of (20.1±3.9) mm at 48 hours of incubation. As for broth microdilution method, the minimal inhibitory concentration (MIC) ranges of ibuprofen against aspergillus spp. were 1000-2000 μg/ml, and the minimal fungicidal concentration (MFC) ranges of that was 2000-8000 μg/ml. For 2 of 5 isolates, when ibuprofen combined with itraconazole or voriconazole, the zones of growth inhibition were larger than those of the individual drug. The results of Chequerboard method showed that fractional inhibitory concentration index (FICI) ranges were 1.125-2.500.Conclusions Ibuprofen is active against aspergillus spp.. And ibuprofen does not affect the in vitro activity of itraconazole, voriconazole, amphotericin B or micafungin against aspergillus spp..

  17. 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.

  18. Detection of Aspergillus-specific antibodies by agar gel double immunodiffusion and IgG ELISA in feline upper respiratory tract aspergillosis.

    Science.gov (United States)

    Barrs, V R; Ujvari, B; Dhand, N K; Peters, I R; Talbot, J; Johnson, L R; Billen, F; Martin, P; Beatty, J A; Belov, K

    2015-03-01

    Feline upper respiratory tract aspergillosis (URTA) is an emerging infectious disease. The aims of this study were: (1) to assess the diagnostic value of detection of Aspergillus-specific antibodies using an agar gel double immunodiffusion (AGID) assay and an indirect immunoglobulin G (IgG) ELISA; and (2) to determine if an aspergillin derived from mycelia of Aspergillus fumigatus, Aspergillus niger and Aspergillus flavus can be used to detect serum antibodies against cryptic Aspergillus spp. in Aspergillus section Fumigati. Sera from cats with URTA (group 1: n = 21) and two control groups (group 2: cats with other upper respiratory tract diseases, n = 25; group 3: healthy cats and cats with non-respiratory, non-fungal illness, n = 84) were tested. Isolates from cats with URTA comprised A. fumigatus (n = 5), A. flavus (n = 1) and four cryptic species: Aspergillus felis (n = 12), Aspergillus thermomutatus (Neosartorya pseudofischeri, n = 1), Aspergillus lentulus (n = 1) and Aspergillus udagawae (n = 1). Brachycephalic purebred cats were significantly more likely to develop URTA than other breeds (P = 0.013). The sensitivity (Se) of the AGID was 43% and the specificity (Sp) was 100%. At a cut-off value of 6 ELISA units/mL, the Se of the IgG ELISA was 95.2% and the Sp was 92% and 92.9% for groups 2 and 3 cats, respectively. Aspergillus-specific antibodies against all four cryptic species were detected in one or both assays. Assay Se was not associated with species identity. Detection of Aspergillus-specific antibodies by IgG ELISA has high Se and Sp for diagnosis of feline URTA. PMID:25634077

  19. Environmental contamination by Aspergillus spp. in laying hen farms and associated health risks for farm workers.

    Science.gov (United States)

    Cafarchia, Claudia; Camarda, Antonio; Iatta, Roberta; Danesi, Patrizia; Favuzzi, Vincenza; Di Paola, Giancarlo; Pugliese, Nicola; Caroli, Anna; Montagna, Maria Teresa; Otranto, Domenico

    2014-03-01

    Data on the occurrence and epidemiology of Aspergillus spp. in laying hens farms are scant. With the aims of determining levels of airborne contamination in laying hen farms and evaluating the potential risk of infection for workers and animals, 57 air samples from 19 sheds (Group I), 69 from faeces (Group II), 19 from poultry feedstuffs (Group III) and 60 from three anatomical sites (i.e. nostrils, pharynx, ears) of 20 farm workers (Group IV) were cultured. The Aspergillus spp. prevalence in samples ranged from 31.6% (Group III) to 55.5% (Group IV), whereas the highest conidia concentration was retrieved in Group II (1.2 × 10(4) c.f.u. g(-1)) and in Group III (1.9 × 10(3) c.f.u. g(-1)). The mean concentration of airborne Aspergillus spp. conidia was 70 c.f.u. m(-3) with Aspergillus fumigatus (27.3%) being the most frequently detected species, followed by Aspergillus flavus (6.3%). These Aspergillus spp. were also isolated from human nostrils (40%) and ears (35%) (Pdisease in hens, it causes human colonization. Correct management of hen farms is necessary to control environmental contamination by Aspergillus spp., and could lead to a significant reduction of animal and human colonization. PMID:24430250

  20. Prevalence of Aspergillus species in clinical samples isolated in an Indian tertiary care hospital

    Directory of Open Access Journals (Sweden)

    Xess Immaculata

    2004-12-01

    Full Text Available CONTEXT (BACKGROUND: In recent times, it has become important to determine the prevalence of different Aspergillus species in clinical samples in view of difference in antifungal susceptibility noted in some species. AIMS: To determine the species prevalence of Aspergillus isolates in various clinical samples received in the Mycology Laboratory at our institute. METHOD: Over a period of 4-years, a total of 18,731 samples were processed, and species identification carried out by standard microbiological methods. RESULTS: Four hundred and fifty six samples (2.43% were culture positive for Aspergillus species. A.flavus (46.93% was the most common isolate, followed by A.fumigatus (37.72% and A.niger (15.35%. It was observed that A.fumigatus was the predominant species isolated from blood and respiratory specimens, A.flavus was predominantly isolated from nasal polyps whereas A.niger predominated in nail specimens. Culture positivity was highest in the age group 12-65 years and in males. Sixty-nine patients (15.13% were admitted to the intensive care unit. CONCLUSIONS: The study highlights the diverse manifestations caused by Aspergillus species in human beings and also throws light on the different species prevalent locally. The knowledge would prove useful in selecting empirical antifungal therapy and formulating prophylactic and pre-emptive strategies.

  1. Aspergillus antigen skin test (image)

    Science.gov (United States)

    The aspergillus antigen skin test determines whether or not a person has been exposed to the mold aspergillus. It is performed by injecting an aspergillus antigen under the skin with a needle. After 48 ...

  2. APPLICATION OF ULTRASOUND TO CONTROL OF ASPERGILLUS FLAVUS IN COSMETICS = APLICAÇÃO DE ULTRASSOM NO CONTROLE DE ASPERGILLUS FLAVUS EM COSMÉTICOS

    OpenAIRE

    Kassima Timoni Góes-Campanha; Dejanira de Franceschi de Angelis; Gerson Antonio Santarine; Carlos Renato Corso; Roberto Naves Domingos

    2011-01-01

    The effect of ultrasound on organic compounds in living tissue and are often related to the cavitation’ phenomenon, a term used to describe the formation of cavities or bubbles in a liquid medium containing varying amounts of gas or vapor that are dissolved in the middle. In medicine it is suggested that ultrasound of high intensity is able to cause some reduction in certain infectious agents and microbiology, mechanisms of inactivation of cells appear to be associated with cavitation. Due to...

  3. Effect of gamma radiation in peanuts for inhibition of Aspergillus flavus and nutritional composition; Irradiacao gama em amendoim para controle de Aspergillus flavus

    Energy Technology Data Exchange (ETDEWEB)

    Costa, L.F.; Silva, E.B. da, E-mail: lauryfrancis@gmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Energia Nuclear; Oliveira, I.S. [Universidade Federal de Pernambuco (CAV/UFPE), Vitoria de Santo Antao, PE (Brazil). Centro Academico de Vitoria

    2013-08-15

    Care in food storage, controlling humidity and temperature, prevents fungal diseases in peanuts and the development of filamentous fungi in food and feed, which can result in the production of toxins known as mycotoxins. Ionizing radiation is a preventive method of food security, promoting inhibition of buds, delayed maturation, reduction of microbial load, elimination of pathogenic microorganisms, sterilization and disinfection in grains, cereals, fruits and spices. This work aimed to evaluate the effects of gamma radiation on the growth inhibition of aflatoxigenic fungi and on nutritional composition in peanut. Samples were collected directly from the producer (Petrolandia) and Supply Central of Pernambuco (CEASA-PE), and then grains inside / outside pods were packed and subjected to irradiation at doses of 6, 9, 12 and 15 kGy. Fungal growth and nutritional composition of the samples before and after irradiation were analyzed and statistical analysis using the Mann-Whitney-Wilcoxon. The results showed that the samples originated from CEASA-PE had the highest rates of contamination. The radiation was effective in the inhibition of aflatoxigenic fungi, achieving to eliminate the action of fungi, regardless of dose. Only one non-irradiated sample, originated from CEASA-PE, showed positive production of aflatoxins in the middle LCA. No significant difference in the values of the nutritional composition, with increasing radiation dose. The irradiation was shown to be an effective process for preserving peanuts, because it prevents the growth of fungi, particularly aflatoxin producer, making it safer for consumption, without changing its nutritional composition. (author)

  4. Aspergillus spinal epidural abscess

    International Nuclear Information System (INIS)

    A spinal epidural abscess developed in a renal transplant recipient; results of a serum radioimmunoassay for Aspergillus antigen were positive. Laminectomy disclosed an abscess of the L4-5 interspace and L-5 vertebral body that contained hyphal forms and from which Aspergillus species was cultured. Serum Aspergillus antigen radioimmunoassay may be a valuable, specific early diagnostic test when systemic aspergillosis is a consideration in an immunosuppressed host

  5. Distribution of Aspergillus species among apparently healthy birds in poultry farms in Kaduna state, Nigeria

    Directory of Open Access Journals (Sweden)

    Clara N Kwanashie

    2013-03-01

    Full Text Available The study wasconducted to determine the prevalence and distribution of Aspergilllus species among apparently healthy birds in poultryfarms. Trachea swabs from 1500 birds in 52 commercial (10% of birds in eachpoultry farm visited poultry farms were collected for this study. Six speciesof Aspergillus were isolated wasisolated from 718 (47.87% of the birds viz: A. fumigatus made up 52.37% (376 of the Aspergillus isolates followed by A. flavus 21.87% (157, A.niger 11.42% (82, A. terreus8.64% (62, A. restrictus 2.79% (20and A. ochraceous 2.92% (21. Aspergillus species was found to occurthroughout the year in the farms though with a higher incidence during therainy season compared to the dry season.

  6. Molecular ecology of aspergillus section flavi species : approaches to understand the role of aflatoxin genes in aflatoxin biosynthesis

    OpenAIRE

    Abdel-Hadi, Ahmed

    2011-01-01

    This is the first study to integrate and correlate the effect of ecophysiological factors on the life cycle of Aspergillus flavus by carrying out complementary work on gene expression of the aflatoxin gene cluster, with growth, sporulation and phenotypic toxin production. This information was used to understand the role of ecological factors on key biosynthetic genes and examine the use of such information for control of aflatoxin production using RNA interference. Ecologica...

  7. A survey on distribution and toxigenicity of Aspergillus section Flavi in poultry feeds.

    Science.gov (United States)

    Astoreca, A L; Dalcero, A M; Pinto, V Fernández; Vaamonde, G

    2011-03-15

    Thirty-five samples of poultry feeds and corresponding raw materials (maize, soybean and meat meal) from a processing plant were analyzed to evaluate the distribution and toxigenicity of Aspergillus section Flavi isolates. Mycological analysis of the samples indicated the presence of five fungal genera (Aspergillus, Penicillium, Fusarium, Cladosporium, and Eurotium). Aspergillus flavus was the predominant species being present in 48.5% of the analyzed samples. Ninety-one isolates belonging to Aspergillus section Flavi were isolated; ninety were identified as A. flavus and only one as A. parasiticus. Fifty-seven isolates were capable of producing sclerotia, 41 were identified as L-type strains and 16 as type S. Fifty-seven percent of the isolates produced AFB₁ levels ranging from 0.05 μg/kg to 27.7 μg/kg whereas 86.8% produced CPA from 1.5 μg/kg to 137.8 μg/kg. L-strains produced from 0.05 to 14.8 μg/kg of aflatoxin and type S produced levels from 0.05 to 1.65 μg/kg. No significant differences in CPA production among S- and L-strains were observed. Sclerotial isolates produced AFB₁ levels ranging between 0.05 and 27.7 μg/kg and CPA levels from 3.8 to 47.3 μg/kg. More than half of the A. flavus isolates were able to produce AFB and CPA simultaneously. Twenty percent of the 35 samples were contaminated with aflatoxin B₁ whereas 34.3% were contaminated with CPA. The high rate of CPA producing isolates represents a potential risk of contamination with this toxin in poultry feeds. PMID:21354643

  8. Uso da BM&F - Bolsa de Mercadorias e Futuros - por Produtores, Cerealistas e Cooperativas

    Directory of Open Access Journals (Sweden)

    Manuela Rösing Agostini

    2012-04-01

    Full Text Available O presente artigo tem como objetivo analisar a adesão aos contratos futuros da BM&F, por parte dos produtores rurais, cerealistas e cooperativas rurais do Corede Nordeste - RS. Dentre as ferramentas disponíveis para proteção de preço no momento da comercialização de soja, os públicos estudados neste trabalho tem como opção os contratos futuros de derivativos junto a BM&F. Através de pesquisa exploratória, com entrevistas em profundidade, realizadas por contato telefônico, foram aplicados questionários com questões relacionadas: a adesão ou não aos contratos futuros da BM&F, a aversão ou propensão ao risco, e quais as ferramentas que estes públicos utilizam para proteção do preço do soja. Dentre as conclusões, percebe-se que há três posicionamentos, específicos para cada público, sendo: os produtores rurais ainda não possuem grande conhecimento quanto a BM&F; as cooperativas rurais dividem-se nas percepções, e existem tanto aquelas atuantes com contratos junto a BM&F, tanto aquelas que apenas realizam contratos futuros com empresas regionais, ou troca de insumos por grãos com os produtores; já por parte dos cerealistas, verifica-se maior propensão ao uso da ferramenta estudada.

  9. Metabolomics of Aspergillus fumigatus

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian; Rank, Christian; Nielsen, Kristian Fog; Larsen, Thomas Ostenfeld

    2009-01-01

    Aspergillus fumigatus is the most important species in Aspergillus causing infective lung diseases. This species has been reported to produce a large number of extrolites, including secondary metabolites, acids, and proteins such as hydrophobins and extracellular enzymes. At least 226 potentially...

  10. Enumeration and identification of Aspergillus group and Penicillium species in poultry feeds from Argentina.

    Science.gov (United States)

    Magnoli, C; Dalcero, A M; Chiacchiera, S M; Miazzo, R; Saenz, M A

    1998-01-01

    A total of 180 samples of poultry feeds were collected during 1996 and 1997 from different factories in the south of the province of Córdoba-Argentina. They were examined for the occurrence of Penicillium spp. and Aspergillus group species. Likewise, the capacity to produce aflatoxins by the Aspergillus section flavi group was determined. The predominant species of Aspergillus were A. flavus and A. parasiticus. For Penicillium spp., P. brevicompactum, P. purpurogenum and P. oxalicum were identified. Less frequently isolated were A. candidus, A. fumigatus, A. niger, A. orizae, A. parvulus, A. tamarii, A. terreus, and P. expansum, P. funiculosum, P. minioluteum, P. pinophylum, P. restrictum, P. variable and others. The mean value counts ranged from 1 x 10(3) to 9.5 x 10(4) CFU/g for the Aspergillus spp. and from 1.2 x 10(3) to 2.5 x 10(5) CFU/g for the Penicillium spp. When cultured on autoclaved rice kernels for 1 week in the dark at 25 degrees C, mycotoxin production by strains of A. flavus was as follows: 21 of the 45 assayed strains (47%) produced aflatoxins. From them, 24% of the isolates produced AFB1 and AFB2 with levels from 181 to 14545 and 6 to 3640 micrograms/kg respectively. Only 10 strains produced AFB1 with levels from 10 to 920 micrograms/kg. Fifty percent of the A. parasiticus strain was toxicogenic; six aflatoxicogenic profiles were identified. Only 10% of the strains produced all of the aflatoxins. These results showed that a potential exists for the production of mycotoxins by the Aspergillus section flavi and the Penicillium spp. They also suggested an association of mycotoxicosis with poultry feeds in Argentina. PMID:9850595

  11. Biological control of AFB1-producing Aspergillus section Flavi strains isolated from brewer's grains, alternative feed intended for swine production in Argentina.

    Science.gov (United States)

    Asurmendi, Paula; García, María J; Ruíz, Francisco; Dalcero, Ana; Pascual, Liliana; Barberis, Lucila

    2016-07-01

    The aim of the present study was to investigate the inhibitory activity of lactic acid bacteria (LAB) isolated from brewer's grains on Aspergillus section Flavi growth and aflatoxin B1 production. The Aspergillus strains tested were inhibited by all the LAB strains assayed. The isolates Lactobacillus brevis B20, P. pentosaceus B86, Lactococcus lactis subsp. lactis B87, L. brevis B131, and Lactobacillus sp. B144 completely suppressed the fungal growth and reduced aflatoxin B1 production. In conclusion, LAB isolated from brewer's grains show a high inhibitory activity on fungal growth and aflatoxin biosynthesis by Aspergillus flavus and Aspergillus parasiticus. Further studies must be conducted to evaluate the success of in vitro assays under food environment conditions and to elucidate the antifungal mechanism of these strains. PMID:27070819

  12. A realidade da cadeia do trigo no Brasil: o elo produtores/cooperativas

    Directory of Open Access Journals (Sweden)

    Argemiro Luís Brum

    2008-03-01

    Full Text Available O presente artigo tem como objeto a cadeia produtiva do trigo no Brasil e destaca a realidade econômica de seus principais elos, com ênfase nos elos da produção agrícola e industrial do cereal. Salienta-se que o artigo traz a atualidade do setor no Brasil, a partir da análise dos resultados de pesquisa de campo realizada com produtores rurais, cooperativas e moinhos de trigo. O estudo da cadeia tritícola brasileira, com seus problemas, oferece uma luz para melhor compreensão das condições que o país possui para não só responder às dúvidas expostas, mas, sobretudo, apontar o caminho seguido pela produção de trigo no Brasil nesse início de século XXI. A triticultura nacional está ameaçada e dificilmente alcançará a auto-suficiência, pois os produtores brasileiros não possuem vantagens comparativas e competitivas suficientes, particularmente em relação aos produtores argentinos. A comercialização do trigo também enfrenta dificuldades, tanto na questão de preços do produto, quanto na qualidade exigida pelos moinhos. A retirada da intervenção estatal na produção nacional de trigo, em 1990/91, que a deixou ao sabor do mercado, alterou completamente o quadro de competitividade dos produtores e da própria cadeia produtiva. Uma das principais conclusões é de que a cadeia tritícola brasileira não funciona a contento, a eficiência da produção nacional está em xeque e seu futuro, comprometido.The present article is about the wheat productive chain in Brazil and focuses on the economic reality of its main connecting links, with emphasis on the links between agricultural and industrial production. Let it be accentuated that the article brings present time accounts of the sector in Brazil, from the result analysis of field research among agricultural producers, producer co-operatives and wheat mills. The study of the Brazilian wheat culture chain, with its problems, offers a broader view to understand the e country

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

    DEFF Research Database (Denmark)

    Andersen, Mikael Rørdam; Vongsangnak, Wanwipa; Panagiotou, Gianni; Salazar, Margarita Pena; Lehmann, Linda Olkjær; Nielsen, Jens

    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...

  14. Aspergillus flavus: controllo della biosintesi di aflatossina e strategie di biocompetizione

    OpenAIRE

    Degola, Francesca

    2013-01-01

    L'aflatossina B1 è considerata una delle micotossine più pericolose per la salute dell'uomo e degli animali. La contaminazione di alimenti e mangimi che può verificarsi, a seguito dell’infezione fungina, in ogni fase del loro processo di trasformazione (dal campo alla tavola) è causa di gravi perdite economiche. Una delle strategie che attualmente è considerata tra le più promettenti nel contenere il "rischio aflatossine" consiste nell’uso della bio-competizione quale mezzo di prevenzione del...

  15. Inhibitory activity of compounds isolated from Polymnia sonchifolia on aflatoxin production by Aspergillus flavus

    OpenAIRE

    Pak Adriana; Gonçalez Edlayne; Felicio Joana D'arc; Pinto Marina Mori; Rossi Maria Helena; Simoni Isabela Cristina; Lopes Márcia Nasser

    2006-01-01

    Polymnia sonchifolia, commonly known as ";yacon";, was originally cultivated at Andes moutains in South America. Recently, the specie attracted worldwide attention because of its wide range of uses, for example in the control of diabetes melitus, besides the antifungal and pesticidal compounds were found in the leaves. This study describes the identification of two flavonoids: 3', 5, 7 trihydroxy-3, 4'-dimethoxyflavone (compound 1) and 3', 4', 5- trihydroxy-7-methoxy flavanone (compound 2) an...

  16. PRODUCTION OF α-AMYLASE FROM ASPERGILLUS FLAVUS UNDER SOLID STATE FERMENTATION WITH OPTIMUM CONDITIONS

    Directory of Open Access Journals (Sweden)

    Mamatha J

    2012-08-01

    Full Text Available α-amylases are ubiquitous enzymes produced by plants, animals and microbes, where they play a dominant role in carbohydrate metabolism. In spite of the wide distribution of amylases, microbial sources, namely fungal and bacterial amylases, are used for the industrial production due to advantages such as cost effectiveness, consistency, less time and space required for production and ease of process modification and optimization. Filamentous fungi are known to be prolific producers of extracellular proteins; they are widely exploited for the production of different enzymes including a-amylase. SSF is generally defined as the growth of microorganisms on moist solid substrates with negligible free water, which is preferred than SmF because of simple technique, low capital investment, lower levels of catabolite repression, end- product inhibition, low waste water output, better product recovery and high quality production. Different substrates such as wheat bran, mollasses bran, rice bran, maize meal and sugarcane bagasse were used; out of which sugarcane bagasse has been reported to produce promising results. Different carbon and nitrogen supplements were given which increased the yield of the enzyme and optimized the pH as 6.0 and temperature 300C. Thus the maximum production of amylase was observed at optimized conditions, which can be employed in large scale.

  17. 40 CFR 180.1206 - Aspergillus flavus AF36; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... flavis AF 36 is temporarily exempt from the requirement of a tolerance on corn, field, forage; corn, field, grain; corn, field, stover; corn, pop, grain; corn, pop, stover; corn, sweet, forage; corn, sweet, kernel plus cob with husks removed; corn, sweet, stover when used in accordance with the Experimental...

  18. 40 CFR 180.1254 - Aspergillus flavus NRRL 21882; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... NRRL 21882 on corn, field, forage; corn, field, grain; corn, field, stover; corn, field, aspirated grain fractions; corn, sweet, kernel plus cob with husk removed; corn, sweet, forage; corn, sweet, stover; corn, pop, grain; and corn, pop, stover....

  19. Detection of aflatoxigenic aspergillus flavus contamination of coconut (cocos nucifera) nutmeat (copra) using ammonia treatment

    Science.gov (United States)

    For many crops government regulations define mycotoxin contamination levels that represent the primary determinants of quality, value and possible uses of crops. Quality can be raised in some crops by lowering the mycotoxin level through removal of infected products. In the case of copra, the drie...

  20. Visualization of aflatoxigenic Aspergillus flavus contamination of coconut (Cocos nucifera) nutmeat (Copra) using ammonia treatment

    Science.gov (United States)

    For many crops government regulations define mycotoxin contamination levels that reflect the primary determinants of quality, value and possible uses of crops. Quality can be raised by lowering the mycotoxin level through a remediation process. In the case of copra, the dried nutmeat of the coconu...

  1. PRODUCTION OF α-AMYLASE FROM ASPERGILLUS FLAVUS UNDER SOLID STATE FERMENTATION WITH OPTIMUM CONDITIONS

    OpenAIRE

    Mamatha J; Suresh V; Vedamurthy AB; Shilpi B; Shruthi SD

    2012-01-01

    α-amylases are ubiquitous enzymes produced by plants, animals and microbes, where they play a dominant role in carbohydrate metabolism. In spite of the wide distribution of amylases, microbial sources, namely fungal and bacterial amylases, are used for the industrial production due to advantages such as cost effectiveness, consistency, less time and space required for production and ease of process modification and optimization. Filamentous fungi are known to be prolific producers of extracel...

  2. Effect of gamma radiation in peanuts for inhibition of Aspergillus flavus and nutritional composition

    International Nuclear Information System (INIS)

    Care in food storage, controlling humidity and temperature, prevents fungal diseases in peanuts and the development of filamentous fungi in food and feed, which can result in the production of toxins known as mycotoxins. Ionizing radiation is a preventive method of food security, promoting inhibition of buds, delayed maturation, reduction of microbial load, elimination of pathogenic microorganisms, sterilization and disinfection in grains, cereals, fruits and spices. This work aimed to evaluate the effects of gamma radiation on the growth inhibition of aflatoxigenic fungi and on nutritional composition in peanut. Samples were collected directly from the producer (Petrolandia) and Supply Central of Pernambuco (CEASA-PE), and then grains inside / outside pods were packed and subjected to irradiation at doses of 6, 9, 12 and 15 kGy. Fungal growth and nutritional composition of the samples before and after irradiation were analyzed and statistical analysis using the Mann-Whitney-Wilcoxon. The results showed that the samples originated from CEASA-PE had the highest rates of contamination. The radiation was effective in the inhibition of aflatoxigenic fungi, achieving to eliminate the action of fungi, regardless of dose. Only one non-irradiated sample, originated from CEASA-PE, showed positive production of aflatoxins in the middle LCA. No significant difference in the values of the nutritional composition, with increasing radiation dose. The irradiation was shown to be an effective process for preserving peanuts, because it prevents the growth of fungi, particularly aflatoxin producer, making it safer for consumption, without changing its nutritional composition. (author)

  3. Effects of hydrogen peroxide on different toxigenic and atoxigenic isolates of Aspergillus flavus

    Science.gov (United States)

    Drought stress in the field has been shown to exacerbate aflatoxin contamination of maize and peanut. Drought and heat stress also produce reactive oxygen species (ROS) in plant tissues. Given the potential correlation between ROS and exacerbated aflatoxin production under drought and heat stress, t...

  4. Diversity, molecular phylogeny and fingerprint profiles of airborne Aspergillus species using random amplified polymorphic DNA.

    Science.gov (United States)

    Kermani, Firoozeh; Shams-Ghahfarokhi, Masoomeh; Gholami-Shabani, Mohammadhassan; Razzaghi-Abyaneh, Mehdi

    2016-06-01

    In the present study, diversity and phylogenetic relationship of Aspergillus species isolated from Tehran air was studied using random amplified polymorphic DNA (RAPD)-polymerase chain reaction (RAPD-PCR). Thirty-eight Aspergillus isolates belonging to 12 species i.e. A. niger (28.94 %, 11 isolates), A. flavus (18.42 %, 7 isolates), A. tubingensis (13.15 %, 5 isolates), A. japonicus (10.52 %, 4 isolates), A. ochraceus (10.52 %, 4 isolates), and 2.63 %, 1 isolate from each A. nidulans, A. amstelodami, A. oryzae, A. terreus, A. versicolor, A. flavipes and A. fumigatus were obtained by settle plate method which they were distributed in 18 out of 22 sampling sites examined. Fungal DNA was extracted from cultured mycelia of all Aspergillus isolates on Sabouraud Dextrose Agar and used for amplification of gene fragments in RAPD-PCR using 11 primers. RAPD-PCR data was analyzed using UPGMA software. Resulting dendrogram of combined selected primers including PM1, OPW-04, OPW-05, P160, P54, P10 and OPA14 indicated the distribution of 12 Aspergillus species in 8 major clusters. The similarity coefficient of all 38 Aspergillus isolates ranged from 0.02 to 0.40 indicating a wide degree of similarities and differences within and between species. Taken together, our results showed that various Aspergillus species including some important human pathogenic ones exist in the outdoor air of Tehran by different extents in distribution and diversity and suggested inter- and intra-species genetic diversity among Aspergillus species by RAPD-PCR as a rapid, sensitive and reproducible method. PMID:27116962

  5. Antifungal activity of Oleoresins used in meat industry on some toxigenic Aspergillus spp.

    Directory of Open Access Journals (Sweden)

    Šošo Vladislava M.

    2013-01-01

    Full Text Available Different spice oleoresins are widely used in meat industry. They contribute to the specific aroma and flavor of the end products, but they have also been reported to have strong antimicrobial activity. These properties open a plenty of possibilities to be used for defining the specific sensory profile of the product but also as natural food preservatives. This paper focuses on the antifungal activity of four oleoresins against different foodborne toxigenic Aspergillus species. Oleoresins used in the experiments were cayenne pepper, black pepper, garlic and rosemary oleoresins, and they were tested against following Aspergillus species: A. clavatus, A. flavus, A. fumigatus, A. niger, A. ochraceus and A. versicolor. Antifungal activity was tested using microtitre-plate-based assay incorporating resazurin as an indicator of cell growth and broth microdilution-method. [Projekat Ministarstva nauke Republike Srbije, br. III46009

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

    Institute of Scientific and Technical Information of China (English)

    SHI Jun-yan; WANG He; GUO Li-na; XU Ying-chun; SHI Yi; L(U) Huo-xiang; LIU Yong; ZHAO Wang-sheng; CHEN Dong-mei; XI Li-yan; ZHOU Xin

    2010-01-01

    Background 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.Methods 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℃. MIC50, MIC90 and MIC range were acquired by Whonet 5.4 software.Results The MIC90 of caspofungin against A. fumigatus, A. flavus and A. nidulans was 0.094 μg/ml whereas the MIC90 against A. niger was 0.19 μg/ml. For these four species, the MlC90 of caspofungin was the lowest among the five antifungal agents. For A. terrus, the MIC90 of posaconazole was the lowest. For A. fumigatus and A. flavus, the MlC90in 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.Conclusions 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.

  7. Mycoflora and ochratoxin A producing strains of Aspergillus in Algerian wheat.

    Science.gov (United States)

    Riba, A; Mokrane, S; Mathieu, F; Lebrihi, A; Sabaou, N

    2008-02-29

    Wheat is a basic staple food for very large segments of the population of Algeria. The aim of this study is to analyse ochratoxin A (OTA)-producing mould and OTA-contaminated wheat. To evaluate the mycoflora and the potential for OTA production by Aspergillus strains, a total of 85 samples of wheat destined for human consumption were collected from two regions in Algeria (Tizi Ouzou and Setif) during the following phases: preharvest, storage in silos, and after processing. The mean value counts of fungi ranged from 275 to 1277 CFU g(-1). The dominant genus was Aspergillus, predominantly A. flavus, A. niger and A. versicolor. The other isolated species were A. ochraceus, A. alliaceus, A. carbonarius, A. terreus, A. fumigatus, A. candidus and Aspergillus spp. The occurrence and the levels of the genus Penicillium, Fusarium, Alternaria and Mucor were substantially lower than those of Aspergillus. The storage in silos shows high levels of Aspergillus (66 to 84%), especially A. flavus, but A. niger and other fungi were isolated at relatively low percentages. Equal distribution of the fungal contamination into the bran, flour and semolina fractions was observed from Flour Mill and Semolina Mill. The genus Aspergillus remained present at high levels at several phases of the production process. In addition, the ability to produce OTA by 135 isolates belonging to eleven species of Aspergillus and 23 isolates of Penicillium spp. was analyzed using fluorescent detection-based HPLC. Thus, it was found that 51 isolates (32.3%) were ochratoxigenic. All isolated strains of A. ochraceus (12) and A. alliaceus (6) produced OTA at concentrations ranging from 0.23 to 11.50 microg g(-1). Most of the A. carbonarius strains (80%) were OTA producers (0.01 to 9.35 microg g(-1)), whereas A. terreus (50%), A. niger (28%), A. fumigatus (40%), A. versicolor (18%) and Penicillium spp. (21.7%) were low level producers (0.01 to 0.07 microg g(-1)). The concentration of OTA was determined in 30

  8. (+)-Geodin from Aspergillus terreus

    DEFF Research Database (Denmark)

    Rønnest, Mads Holger; Nielsen, Morten Thrane; Leber, Blanka; Mortensen, Uffe Hasbro; Krämer, Alwin; Clausen, Mads Hartvig; Larsen, Thomas Ostenfeld; Harris, Pernille

    The fungal metabolite (+)-geodin [systematic name: (2R)-methyl 5,7-dichloro-4-hydroxy-6'-methoxy-6-methyl-3,4'-dioxospiro[benzofuran-2,1'-cyclohexa-2',5'-diene]-2'-carboxylate], C(17)H(12)Cl(2)O(7), was isolated from Aspergillus terreus. The crystal structure contains two independent molecules in...

  9. Isolation of culturable mycobiota from agricultural soils and determination of tolerance to glyphosate of nontoxigenic Aspergillus section Flavi strains.

    Science.gov (United States)

    Carranza, Cecilia S; Barberis, Carla L; Chiacchiera, Stella M; Dalcero, Ana María; Magnoli, Carina E

    2016-01-01

    Glyphosate-based herbicides are extensively used in Argentina's agricultural system to control undesirable weeds. This study was conducted to evaluate the culturable mycobiota [colony forming units (CFU) g(-1) and frequency of fungal genera or species] from an agricultural field exposed to pesticides. In addition, we evaluated the tolerance of A. oryzae and nontoxigenic A. flavus strains to high concentrations (100 to 500 mM - 17,000 to 84,500 ppm) of a glyphosate commercial formulation. The analysis of the mycobiota showed that the frequency of the main fungal genera varied according to the analyzed sampling period. Aspergillus spp. or Aspergillus section Flavi strains were isolated from 20 to 100% of the soil samples. Sterilia spp. were also observed throughout the sampling (50 to 100%). Aspergillus section Flavi tolerance assays showed that all of the tested strains were able to develop at the highest glyphosate concentration tested regardless of the water availability conditions. In general, significant reductions in growth rates were observed with increasing concentrations of the herbicide. However, a complete inhibition of fungal growth was not observed with the concentrations assayed. This study contributes to the knowledge of culturable mycobiota from agricultural soils exposed to pesticides and provides evidence on the effective growth ability of A. oryzae and nontoxigenic A. flavus strains exposed to high glyphosate concentrations in vitro. PMID:26549415

  10. Radiosensitivity of toxigenic Aspergillus isolated from spices and destruction of aflatoxins by gamma-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kume, Tamikazu; Ito, Hitoshi; Ishigaki, Isao (Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment); Soedarman, Harsono (National Atomic Energy Agency, Jakarta (Indonesia). Centre for the Application of Isotopes and Radiation)

    1989-01-01

    Radiosensitivities of Aspergillus flavus var columnaris isolated from spices were investigated. The D{sub 10} values and induction doses were 267-293 Gy and 75-165 Gy in wet conditions, respectively. In dry conditions, the survival curves were exponential and D{sub 10} values were 538-600 Gy. The survival curves of standard strain of A. parasiticus IFO 30179 were similar both in wet and dry conditions. The necessary dose of 8 kGy for the destruction of these toxigenic Aspergillus was calculated from these values. Two of 11 strains of A. flavus var columnaris produced aflatoxins and the content of B{sub 1} was especially high. In the study of irradiation effect on aflatoxins produced on polished rice, aflatoxins G{sub 1} and B{sub 1} were more radiosensitive than G{sub 2} and B{sub 2}. However, these aflatoxins were very stable to radiation and the dose required for destruction was found to be more than 500 kGy. It is therefore concluded that the decontamination of molds by irradiation is necessary prior to their production of aflatoxins.

  11. Chemical composition and antifungal activity of Hyptis suaveolens (L. poit leaves essential oil against Aspergillus species

    Directory of Open Access Journals (Sweden)

    Ana Carolina Pessoa Moreira

    2010-03-01

    Full Text Available This study aimed to identify the constituents of the essential oil from Hyptis suaveolens (L. leaves using a Gas Chromatograph -Mass Spectrometer and assess its inhibitory effect on some potentially pathogenic Aspergilli (A. flavus, A. parasiticus, A. ochraceus, A. fumigatus and A. niger. Eucaliptol (47.64 % was the most abundant component in the oil, followed for gama-ellemene (8.15 %, beta-pynene (6.55 %, (+3-carene (5.16 %, trans-beta-cariophyllene (4.69 % and germacrene (4.86 %. The essential oil revealed an interesting anti-Aspergillus property characterized by a Minimum Inhibitory Concentration and Minimum Fungicidal Concentration of 40 and 80 µL/mL, respectively. The oil at 80 and 40 µL/mL strongly inhibited the mycelial growth of A. fumigatus and A. parasiticus along 14 days. In addition, at 10 and 20 µL/mL the oil was able to cause morphological changes in A. flavus as decreased conidiation, leakage of cytoplasm, loss of pigmentation and disrupted cell structure suggesting fungal wall degeneration. These findings showed the interesting anti-Aspergillus property of H. suaveolens leaves essential oil supporting its possible rational use as alternative source of new antifungal compounds to be applied in the aspergillosis treatment.

  12. Radiosensitivity of toxigenic Aspergillus isolated from spices and destruction of aflatoxins by gamma-irradiation

    International Nuclear Information System (INIS)

    Radiosensitivities of Aspergillus flavus var columnaris isolated from spices were investigated. The D10 values and induction doses were 267-293 Gy and 75-165 Gy in wet conditions, respectively. In dry conditions, the survival curves were exponential and D10 values were 538-600 Gy. The survival curves of standard strain of A. parasiticus IFO 30179 were similar both in wet and dry conditions. The necessary dose of 8 kGy for the destruction of these toxigenic Aspergillus was calculated from these values. Two of 11 strains of A. flavus var columnaris produced aflatoxins and the content of B1 was especially high. In the study of irradiation effect on aflatoxins produced on polished rice, aflatoxins G1 and B1 were more radiosensitive than G2 and B2. However, these aflatoxins were very stable to radiation and the dose required for destruction was found to be more than 500 kGy. It is therefore concluded that the decontamination of molds by irradiation is necessary prior to their production of aflatoxins. (author)

  13. Contaminação endógena por Aspergillus spp. em milho pós-colheita no Estado do Paraná

    Directory of Open Access Journals (Sweden)

    FARIAS ANTONIO XAVIER DE

    2000-01-01

    Full Text Available Sessenta amostras de milho pós-colheita foram avaliadas quanto à contaminação fúngica endógena e o potencial toxígeno de espécies do gênero Aspergillus e seus teleomorfos. Quarenta grãos aparentemente sadios de cada amostra foram desinfestados em NaClO e incubados em câmara úmida a 25±1ºC para exteriorização dos fungos, que posteriormente foram isolados em ágar Czapek-Dox. Foram identificadas as espécies Aspergillus flavus, A. parasiticus, Eurotium amstelodami e E. chevalieri. O potencial toxígeno dos fungos A. flavus e A. parasiticus foi avaliado quanto à síntese de aflatoxinas em meio ágar-coco. Espécies do gênero Eurotium foram avaliadas quanto à síntese de esterigmatocistina, nos meios ágar-amendoim e trigo triturado. A porcentagem de grãos contaminados variou entre 0 e 100%, prevalecendo os gêneros Aspergillus, Penicillium e Fusarium. A espécie predominante foi a A. flavus (64%, seguida por E. amstelodami (19%, E. chevalieri (10% e A. parasiticus (7%. A partir de 109 isolados de A. flavus, evidenciou-se que 73 isolados sintetizaram aflatoxinas B1 e B2, 20 sintetizaram B1, sete sintetizaram B1 e G1, três sintetizaram B1, B2 e G1 e em seis não foi detectada a síntese de aflatoxina. A síntese de esterigmatocistina pelas espécies E. amstelodami e E. chevalieri não foi detectada.

  14. Environmental and clinical epidemiology of Aspergillus terreus: data from a prospective surveillance study.

    Science.gov (United States)

    Rüping, M J G T; Gerlach, S; Fischer, G; Lass-Flörl, C; Hellmich, M; Vehreschild, J J; Cornely, O A

    2011-07-01

    Aspergillus terreus may be resistant to amphotericin B and is associated with significant morbidity and mortality in immunocompromised patients. Local incidence is influenced by the density of airborne Aspergillus spp. spores which may in turn depend on meteorological factors. Once-weekly environmental samples were collected prospectively inside and outside the University Hospital of Cologne, Germany (UHC) and haematological patients were screened for nasal Aspergillus spp. colonisation and monitored for invasive fungal disease (IFD). RAPD (rapid amplification of polymorphic DNA)-polymerase chain reaction (PCR) and amphotericin B susceptibility testing were performed on all A. terreus isolates. A total of 4919 colony-forming units (cfu) were isolated (2212 indoors, 2707 outdoors). Further identification revealed A. fumigatus (73.5%), A. niger (4.3%), A. flavus (1.7%), A. terreus (0.2%) and non-Aspergillus fungi (20.3%). RAPD-PCR did not reveal clonal relationships between the A. terreus isolates. All A. terreus isolates displayed complete resistance to amphotericin. The B. Aspergillus spp. conidia exposure was lowest in June and highest in November inside and outside UHC. Conidia load correlated with the season and the relative humidity, with increasing spore counts during dry periods. One out of 855 nasal swabs was positive for A. niger. The patient did not develop IFD. A. terreus is unlikely to be a relevant pathogen at the UHC. Results from RAPD-PCR suggested a wide epidemiological variety of strains rather than a common source of contamination. Nasal swab surveillance cultures for early detection of Aspergillus spp. colonisation were not useful in identifying patients who may develop IFD. The risk of IFD at the UHC may increase in autumn and during dry periods. PMID:21440331

  15. O excesso de confiança dos produtores de milho no Brasil e o uso de contratos futuros

    Directory of Open Access Journals (Sweden)

    José César Cruz Júnior

    2011-06-01

    Full Text Available O objetivo deste artigo foi identificar sinais de excesso de confiança nos preços entre produtores de milho do Sul e do Centro-Oeste do Brasil. Entre outubro e novembro de 2008, 90 produtores foram selecionados para responderem questões relacionadas a seus conhecimentos do mercado futuro e a suas expectativas de preços. Uma grande parte dos entrevistados respondeu que não negociava contratos futuros por não possuir informação suficiente para isso. Os resultados revelaram que os produtores foram descalibrados quando estimaram os preços esperados na forma direta e indireta. Além disso, para a maior parte dos respondentes, a variância subjetiva obtida por meio dos questionários foi estatisticamente inferior à variância do mercado. Isto mostra que os produtores possuem uma percepção de risco inferior ao risco de mercado. Por fim, o artigo conclui que o efeito de excesso de confiança pode, parcialmente, explicar o baixo uso do mercado futuro de milho por parte dos produtores brasileiros, para garantir a proteção de preço do produto.This paper aimed to identify signs of overconfidence among corn producers in the Southern and Central-Western regions in Brazil. Between October and November 2008, 90 farmers were chosen to answer questions regarding their knowledge of futures markets and price expectations. Most part of agents surveyed answered that they do not trade futures contracts because they do not have enough information. Results showed that respondents were miscalibrated when estimating directly-stated and the indirectly-stated expected prices. In addition, for most respondents, subjective variance for corn proves to be significantly less than the market variance, implying that producers perceive a risk that is lower than that of the market. Finally, the paper concludes that the overconfidence effect can partially explain the low use of futures markets by Brazilian corn producers to hedge their production.

  16. New taxa in Aspergillus section Usti

    DEFF Research Database (Denmark)

    Samson, R. A.; Varga, J.; Meijer, M.;

    2011-01-01

    Based on phylogenetic analysis of sequence data, Aspergillus section Usti includes 21 species, inducing two teleomorphic species Aspergillus heterothallicus (=Emericella heterothallica) and Fennellia monodii. Aspergillus germanicus sp. nov. was isolated from indoor air in Germany. This species ha...

  17. 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.

  18. Antígenos nativos de Aspergillus fumigatus con utilidad para el inmunodiagnóstico de aspergiloma

    OpenAIRE

    José Casquero; Flor Urcia; Elizabeth Sánchez

    2009-01-01

    Con el objetivo de evaluar la utilidad de los antígenos nativos de cepas autóctonas de Aspergillus fumigatus para el inmunodiagnóstico de aspergiloma, se desarrolló un estudio empleando dos cepas de ese hongo, aisladas de pacientes con diagnóstico de aspergiloma (533 y 554), los cuales fueron confrontados con sueros controles comerciales de A. fumigatus, A. flavus, A. niger, Candida, Coccidioides, Histoplasma y Paracoccidioides mediante la prueba de inmunodifusión, asimismo, se evaluaron fren...

  19. Actividad in vitro anti-candida y anti-aspergillus de aceites esenciales de plantas de la familia piperaceae

    OpenAIRE

    Ana Cecilia Mesa; Jehidys Montiel; Catalina Martínez; Bibiana Zapata; Nayive Pino; Juan Gabriel Bueno; Elena Stashenko

    2007-01-01

    Plantas de la familia Piperaceae se han utilizado con fines curativos en diferentes regiones del mundo. El objetivo del presente fue evaluar la actividad antifúngica in vitro de 10 aceites esenciales provenientes de especies del genero Piper, mediante la determinación de la concentración mínima inhibitoria (CMI), con las cepas Aspergillus flavus ATCC 204304 y A. fumigatus ATCC 20430, siguiendo el protocolo CLSI M38-A. Además, se evaluaron las cepas Candida krusei ATCC 6258 y...

  20. Pituitary aspergillus infection.

    Science.gov (United States)

    Moore, Lauren A; Erstine, Emily M; Prayson, Richard A

    2016-07-01

    Fungal infection should be considered in the differential diagnosis of a pituitary or sellar mass, albeit fungal infections involving the pituitary gland and sella are a rare occurrence. We report a case of Aspergillus infection involving the pituitary gland and sellar region discovered in a 74-year-old man. The patient had a history of hypertension, chronic renal disease, autoimmune hemolytic anemia and presented with right eye pain, headaches and worsening hemiparesis. Imaging studies revealed a right internal carotid artery occlusion and an acute right pontine stroke along with smaller infarcts in the right middle cerebral artery distribution. Clinically, the patient was thought to have vasculitis. An infectious etiology was not identified. He developed respiratory distress and died. At autopsy, necrotizing meningitis was discovered. A predominantly chronic inflammatory cell infiltrate consisting of benign-appearing lymphocytes, plasma cells and macrophages was accompanied by acute angle branching, angioinvasive hyphae which were highlighted on Gomori methenamine silver staining and were morphologically consistent with Aspergillus species. In previously reported cases of Aspergillus infection involving the pituitary or sella, most presented with headaches or impaired vision and were not immunocompromised. A transsphenoidal surgical approach is recommended in suspected cases in order to minimize the risk of dissemination of the infection. Some patients have responded well to antifungal medications once diagnosed. PMID:26896907

  1. Biological control of Verticillium dahliae by Talaromyces flavus.

    OpenAIRE

    Nagtzaam, M.P.M.

    1998-01-01

    Verticillium dahliae causes vascular wilt in a wide range of host plants. Control of Verticillium wilt is by soil disinfestation and to a lesser extent by crop rotation or, for a few host plants, by growing resistant varieties. For environmental reasons, the development of alternatives to chemical soil disinfestation is being sought. Biocontrol by microbial agents is one of the options. The potential of Talaromyces flavus as a biocontrol agent in management of the disease is the subject of th...

  2. The effect of humidity after gamma-irradiation on aflatoxin B-1 production of A.flavus in ground nutmeg and peanut

    Energy Technology Data Exchange (ETDEWEB)

    Hilmy, N.; Chosdu, R. [Center for the Application of Isotopes and Radiation, Jakarta (Indonesia); Matsuyama, A. [Tokyo University of Agriculture (Japan). Nodai Research Inst.

    1995-10-01

    The effect of humidity of 75 up to 97% after irradiation on radiosensitivity and aflatoxin B1 production of Aspergillus flavus isolated from Indonesian nutmeg were examined. Irradiation doses used were 0;0.5;1 and 3 kGy. Mould free ground nutmeg and peanut were used as the growth media, and about 10{sup 8} of spores were used to contaminate each of the media. Aflatoxin productions were measured after having incubated 3 days up to 5 months under humidity of 91 and 97%. Prior to HPLC analysis, aflatoxin was cleaned-up using an immunoaffinity column. The results were: (1) A. flavus indicated no or almost no growth under RH of 85% or less. (2) Under 91-97% RH, growth of mycelium and toxin production were inhibited more or less by irradiation up to 1 kGy, although the effectiveness of irradiation varied with different RH and media during postirradiation incubation. (3) By 3 kGy or more, both mycelium growth and toxin production of the mould were found to be completely inhibited. (4) The production of aflatoxin in nutmeg began after having incubated for 25 and 45 days and in peanut for 3 and 6 days under 97 and 91% RH, respectively. (Author).

  3. Radiosensitivity of A. ochraceus, A. flavus, A. niger, A. parasiticus and A. carbonarius in CYA medium and on grains of rice, oat, wheat and peanuts

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Valeria Barbosa [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Faculdade de Veterinaria. Dept. de Tecnologia de Alimentos]. E-mail: niveam@uol.com.br; Vital, Helio de Carvalho; Hernandes, Nilber Kenup [Centro Tecnologico do Exercito, Rio de Janeiro, RJ (Brazil). Div. de Defesa Quimica, Biologica e Nuclear]. E-mail: vital@ctex.eb.br; Rosa, Carlos Alberto da Rocha [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropedica, RJ (Brazil). Inst. de Veterinaria. Dept. de Microbiologia e Imunologia Veterinaria]. E-mail: shalako@ufrrj.br

    2007-07-01

    Irradiation is regarded as an efficient process to delay fungi growth in foods. However information on the resistance of toxigenic molds to gamma radiation is still scarce in the literature. This work investigated the radiosensitivity of five species of Aspergillus spp., namely: A. ochraceus, A. flavus, A. niger, A. parasiticus and A. carbonarius grown and irradiated in CYA medium, peanuts and on grains of rice, oat and wheat. After inoculation the colonies were stored for five days at 25 deg C and gamma irradiated with doses ranging from 0 to 5.5 kGy. Six days later the colonies were analyzed for post-irradiation growth. Survival curves were then determined as linear functions of the absorbed doses. Regardless of the substrates, the radiosensitivities of the five species have been grouped in three different levels. Expressed in terms of the parameters D{sub 50} and Do (the doses needed to reduce the number of active colonies by 50% and 100%, respectively), those groups are: D{sub 50} = 2.2 kGy and D0 = 3.2 kGy for A. ochraceus and A. carbonarius; D{sub 50} = 2.5 kGy and D0 = 4.1 kGy for A. niger and A. flavus; and D{sub 50} = 3.1 kGy and D0 = 4.7 kGy for A. parasiticus. (author)

  4. Radiosensitivity of A. ochraceus, A. flavus, A. niger, A. parasiticus and A. carbonarius in CYA medium and on grains of rice, oat, wheat and peanuts

    International Nuclear Information System (INIS)

    Irradiation is regarded as an efficient process to delay fungi growth in foods. However information on the resistance of toxigenic molds to gamma radiation is still scarce in the literature. This work investigated the radiosensitivity of five species of Aspergillus spp., namely: A. ochraceus, A. flavus, A. niger, A. parasiticus and A. carbonarius grown and irradiated in CYA medium, peanuts and on grains of rice, oat and wheat. After inoculation the colonies were stored for five days at 25 deg C and gamma irradiated with doses ranging from 0 to 5.5 kGy. Six days later the colonies were analyzed for post-irradiation growth. Survival curves were then determined as linear functions of the absorbed doses. Regardless of the substrates, the radiosensitivities of the five species have been grouped in three different levels. Expressed in terms of the parameters D50 and Do (the doses needed to reduce the number of active colonies by 50% and 100%, respectively), those groups are: D50 = 2.2 kGy and D0 = 3.2 kGy for A. ochraceus and A. carbonarius; D50 = 2.5 kGy and D0 = 4.1 kGy for A. niger and A. flavus; and D50 = 3.1 kGy and D0 = 4.7 kGy for A. parasiticus. (author)

  5. Expression Profiling of Non-Aflatoxigenic Aspergillus parasiticus Mutants Obtained by 5-Azacytosine Treatment or Serial Mycelial Transfer

    Directory of Open Access Journals (Sweden)

    Jiujiang Yu

    2011-08-01

    Full Text Available Aflatoxins are carcinogenic secondary metabolites produced by the fungi Aspergillus flavus and Aspergillus parasiticus. Previous studies found that repeated serial mycelial transfer or treatment of A. parasiticus with 5-azacytidine produced colonies with a fluffy phenotype and inability to produce aflatoxins. To understand how these treatments affect expression of genes involved in aflatoxin production and development, we carried out expressed sequence tag (EST-based microarray assays to identify genes in treated clones that are differentially expressed compared to the wild-type. Expression of 183 genes was significantly dysregulated. Of these, 38 had at least two-fold or lower expression compared to the untreated control and only two had two-fold or higher expression. The most frequent change was downregulation of genes predicted to encode membrane-bound proteins. Based on this result we hypothesize that the treatments cause changes in the structure of cellular and organelle membranes that prevent normal development and aflatoxin biosynthesis.

  6. ANÁLISE DA EFICIÊNCIA ECONÔMICA DOS PRODUTORES DE LEITE NO ESTADO DE MINAS GERAIS

    OpenAIRE

    Lima, Andre Luis Ribeiro; Reis, Ricardo Pereira; GAIO, Luiz Eduardo; Andrade, Fabricio Teixeira de; Gomes, Claudia Salgado

    2008-01-01

    O aumento da eficiência produtiva e econômica é fator decisivo para a competitividade do setor leiteiro que, produzindo com menor custo, beneficiará toda a cadeia do leite. Dessa maneira, a unidade de produção pode ter, na eficiência produtiva, a condição necessária para a sobrevivência e o crescimento dentro da economia de mercado. Considerado o maior produtor de leite do Brasil, o estado de Minas Gerais exerce importante papel na cadeia agroindustrial do leite O presente trabalho tem por ob...

  7. New resources for functional analysis of omics data for the genus Aspergillus

    Directory of Open Access Journals (Sweden)

    Meyer Vera

    2011-10-01

    Full Text Available Abstract Background Detailed and comprehensive genome annotation can be considered a prerequisite for effective analysis and interpretation of omics data. As such, Gene Ontology (GO annotation has become a well accepted framework for functional annotation. The genus Aspergillus comprises fungal species that are important model organisms, plant and human pathogens as well as industrial workhorses. However, GO annotation based on both computational predictions and extended manual curation has so far only been available for one of its species, namely A. nidulans. Results Based on protein homology, we mapped 97% of the 3,498 GO annotated A. nidulans genes to at least one of seven other Aspergillus species: A. niger, A. fumigatus, A. flavus, A. clavatus, A. terreus, A. oryzae and Neosartorya fischeri. GO annotation files compatible with diverse publicly available tools have been generated and deposited online. To further improve their accessibility, we developed a web application for GO enrichment analysis named FetGOat and integrated GO annotations for all Aspergillus species with public genome sequences. Both the annotation files and the web application FetGOat are accessible via the Broad Institute's website (http://www.broadinstitute.org/fetgoat/index.html. To demonstrate the value of those new resources for functional analysis of omics data for the genus Aspergillus, we performed two case studies analyzing microarray data recently published for A. nidulans, A. niger and A. oryzae. Conclusions We mapped A. nidulans GO annotation to seven other Aspergilli. By depositing the newly mapped GO annotation online as well as integrating it into the web tool FetGOat, we provide new, valuable and easily accessible resources for omics data analysis and interpretation for the genus Aspergillus. Furthermore, we have given a general example of how a well annotated genome can help improving GO annotation of related species to subsequently facilitate the

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

    DEFF Research Database (Denmark)

    Sørensen, Annette; Lübeck, Peter S.; Lübeck, Mette; Nielsen, Kristian Fog; Ahring, Birgitte K.; Teller, Philip J.; Frisvad, Jens Christian

    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)....

  9. Survey of Aspergillus and Fusarium species and their mycotoxins in raw materials and poultry feeds from Córdoba, Argentina.

    Science.gov (United States)

    Monge, María Del Pilar; Magnoli, Carina Elizabeth; Chiacchiera, Stella Maris

    2012-05-01

    The aims of the present work were: (1) to determine both mycobiota in raw materials and finisher poultry feed, as well as the ability to produce aflatoxin B1 by A. flavus strains, and (2) to evaluate the natural co-occurrence of aflatoxins (AFs), fumonisins (FBs), gliotoxin, diacetoxyscirpenol (DAS), HT-2 toxin, and T-2 toxin in poultry feed by LC-MS/MS. Nineteen percent of raw materials and 79% of finisher poultry feed samples exceeded the maximum allowed total fungal count (1 × 10(4) CFU g(-1)) to ensure hygienic quality. Aspergillus flavus was the only species belonging to section Flavi which was isolated while Fusarium verticilliodes was the prevalent species. Forty-seven percent of A. flavus strains were aflatoxin B1 producers and the highest frequency of aflatoxigenic strains was isolated from finisher poultry feeds. Principal component analysis showed that corn grains are closely related with total fungal and Fusarium counts. This positive relationship suggests that total fungal and Fusarium spp. counts in poultry feed might come mainly from corn grains. Regarding poultry feeds, in ground finisher type, Aspergillus spp. counts increased as water activity (aw) diminished. A positive relationship among aw, total fungal and Fusarium spp. counts was observed in both ground finisher and ground starter feed. Several mycotoxins were monitored in feeds by applying the LC MS/MS technique. One hundred percent of poultry samples were contaminated with FB1, and the highest levels were detected in pelleted finisher poultry. AFB1, gliotoxin, DAS, HT-2 toxin, and T-2 toxin were not detected in any poultry feed. The scarcity of available mycotoxicological studies from Argentinean poultry feed using a multitoxin analysis technique enhances the contribution of the findings of this report. PMID:23606049

  10. Aspergillus-Related Lung Disease

    Directory of Open Access Journals (Sweden)

    Alia Al-Alawi

    2005-01-01

    Full Text Available Aspergillus is a ubiquitous dimorphic fungus that causes a variety of human diseases ranging in severity from trivial to life-threatening, depending on the host response. An intact host defence is important to prevent disease, but individuals with pre-existing structural lung disease, atopy, occupational exposure or impaired immunity are susceptible. Three distinctive patterns of aspergillus-related lung disease are recognized: saprophytic infestation of airways, cavities and necrotic tissue; allergic disease including extrinsic allergic alveolitis, asthma, allergic bronchopulmonary aspergillosis, bronchocentric granulomatosis and chronic eosinophilic pneumonia; and airway and tissue invasive disease -- pseudomembranous tracheobronchitis, acute bronchopneumonia, angioinvasive aspergillosis, chronic necrotizing aspergillosis and invasive pleural disease. A broad knowledge of these clinical presentations and a high index of suspicion are required to ensure timely diagnosis and treatment of the potentially lethal manifestations of aspergillus-related pulmonary disease. In the present report, the clinical, radiographic and pathological aspects of the various aspergillus-related lung diseases are briefly reviewed.

  11. Aspergillus fumigatus in Poultry

    Directory of Open Access Journals (Sweden)

    Pascal Arné

    2011-01-01

    Full Text Available Aspergillus fumigatus remains a major respiratory pathogen in birds. In poultry, infection by A. fumigatus may induce significant economic losses particularly in turkey production. A. fumigatus develops and sporulates easily in poor quality bedding or contaminated feedstuffs in indoor farm environments. Inadequate ventilation and dusty conditions increase the risk of bird exposure to aerosolized spores. Acute cases are seen in young animals following inhalation of spores, causing high morbidity and mortality. The chronic form affects older birds and looks more sporadic. The respiratory tract is the primary site of A. fumigatus development leading to severe respiratory distress and associated granulomatous airsacculitis and pneumonia. Treatments for infected poultry are nonexistent; therefore, prevention is the only way to protect poultry. Development of avian models of aspergillosis may improve our understanding of its pathogenesis, which remains poorly understood.

  12. Resurgence and persistence of Dorymyrmex flavus after reduction of Solenopsis invicta buren with a broadcast bait.

    Science.gov (United States)

    Calixto, Alejandro A; Harris, Marvin K; Barr, Charles

    2007-06-01

    The effects of bait treatment(s) on population dynamics of Solenopsis invicta and Dorymyrmex flavus were studied, and various factors underlying the resurgence and persistence of D. flavus to reinvasion by S. invicta were studied in more detail. Pitfall traps, bait vials, transect sampling, and direct inspections were used to monitor densities of these two species, and inspections of D. flavus midden contents, video monitoring of D. flavus colonies, and studies of the fate of marked S. invicta were used to further clarify interactions of these two species, D. flavus abundance increased after the reduction of S. invicta with baits. D. flavus was also observed to sustain higher densities for an extended period (2 yr) after cessation of bait treatment and to exhibit antagonistic behaviors toward S. invicta, showing an ability to resist reinvasion of the treated area by S. invicta. Given these findings, D. flavus may retard domination of the ant assemblage by S. invicta. Additional studies are justified regarding how to enhance the role of this species in affected ecosystems. PMID:17540063

  13. The use of a-methyl-D-glucoside, a synthetic analogue of maltose, as inducer of amylase by Aspergillus sp in solid-state and submerged fermentations

    OpenAIRE

    Moreira Fabiana G.; Lenartovicz Veridiana; Souza Cristina G. M.; Ramos Edivan P.; Peralta Rosane M.

    2001-01-01

    The use of a methyl-D-glucoside (alphaMG), a synthetic analogue of maltose, as carbon source and inducer of amylase synthesis to several species of Aspergillus was studied in submerged and solid-state fermentations. Among a group of ten species, A. tamarii, A. fumigatus and A. flavus were able to produce biomass and high specific amylolytic activity in submerged cultures containing alphaMG as the only carbon source. In solid state fermentation, the enrichment of basal wheat bran or corn cob m...

  14. Eficiência técnica e desempenho econômico de produtores de leite no Estado do Ceará, Brasil

    Directory of Open Access Journals (Sweden)

    Klinger Aragão Magalhães

    2006-12-01

    Full Text Available Objetiva-se avaliar a eficiência dos produtores pelas medidas de eficiência técnica e de escala e calcular indicadores de desempenho econômico dos produtores de leite do Município de Sobral, Ceará, Brasil. Os dados são de natureza primária, coletados por meio de questionários junto a 40 produtores rurais do referido município. Participaram da amostra apenas os produtores com produção mínima de 15 litros/dia, visto que as produções inferiores são destinadas, basicamente, para o autoconsumo. Foram determinadas as medidas de eficiência para cada uma das unidades produtivas (Decision Making Unit - DMU, utilizando-se a técnica de análise envoltória de dados (DEA e o software DEAP v. 2.1, desenvolvido por Coelli (1996. Inicialmente, os produtores foram separados de acordo com o grau de eficiência técnica e, em seguida, comparados por meio de indicadores econômicos, com a finalidade de determinar a magnitude de performance dos eficientes e dos ineficientes. Conclui-se que há predomínio do grupo de produtores ineficientes (escores de eficiência menor do que 0,9, representando 67,5% da amostra. Portanto, é muito baixo o número de produtores eficientes (32,5% da amostra. Regra geral, os produtores eficientes apresentaram bons resultados econômicos. A margem líquida negativa dos produtores ineficientes indica a grave crise que sofre esse grupo de produtores, confirmada pela desvantajosa relação entre o preço de venda do produto e o custo médio de produção.This study aims to evaluate the producers’ efficiency using measurements of technical and scope efficiencies and calculating indicators of economic performance for milk producers in the municipality of Sobral, Ceará, Brazil. The data type was primary gathered by applying questionnaires to 40 rural producers. The sample included only producers with a minimum yield around 15 liter/day, however yields below that level were consumed by the own farmers. The measurement of

  15. Effect of Essential Oils of Syzygium aromaticum and Melaleuca alternifolia on Isolates of Aspergillus sp.

    Directory of Open Access Journals (Sweden)

    A. Lima

    2014-03-01

    Full Text Available Essential  oils  have  antimicrobial  substances,  lower  cost  and  the  lower  resistance  of microorganism. This study aimed to evaluate the inhibition of mycelial growth of Aspergillus flavus and  A.  niger  with  essential  oils  of  Syzygium  aromaticum  and  Melaleuca  alternifolia.  For  this, aliquots  (0.5,  5,  10  and  15μL  of  essential  oils  from  S.  aromaticum  and  M.  alternifolia   were distributed on the surface of the culture medium Potato Dextrose Agar (PDA with Drigaslsky. In the control treatment were used only plates containing PDA plus chloramphenicol (1%. After 2 hours, a disc (8mm diameter of the isolated mycelium, with 10 days of age on PDA, was peaked to the center of the plates, these plates were sealed and incubated at 282°C, in the dark. The essential  oil  of  S.  aromaticum  inhibited  the  mycelial  growth  of  A.  flavus  and  A.  niger,  in  all aliquots. When using the essential oil of M. alternifolia decreased the mycelial growth of A. flavus in all aliquots, however, showed a low efficiency in control of A. niger. It was concluded that the essential  oil  S.  aromaticum  is  effective  against  A.  flavus  and  A.  niger,  which  can  be  used  in control against these microorganisms, and M. alternifolia not show satisfactory results in relation to reducing the growth of pathogens evaluated.

  16. Inhibitory activity of compounds isolated from Polymnia sonchifolia on aflatoxin production by Aspergillus flavus Produção de aflatoxina por Aspergillus flavus é inibida por compostos isolados de Polymnia sonchifolia

    OpenAIRE

    Adriana Pak; Edlayne Gonçalez; Joana D'arc Felicio; Marina Mori Pinto; Maria Helena Rossi; Isabela Cristina Simoni; Márcia Nasser Lopes

    2006-01-01

    Polymnia sonchifolia, commonly known as ";yacon";, was originally cultivated at Andes moutains in South America. Recently, the specie attracted worldwide attention because of its wide range of uses, for example in the control of diabetes melitus, besides the antifungal and pesticidal compounds were found in the leaves. This study describes the identification of two flavonoids: 3', 5, 7 trihydroxy-3, 4'-dimethoxyflavone (compound 1) and 3', 4', 5- trihydroxy-7-methoxy flavanone (compound 2) an...

  17. A rapid screening method for cutinase producing microorganisms Seleção de microorganismos produtores de cutinase

    Directory of Open Access Journals (Sweden)

    Gabriela Alves Macedo

    2005-12-01

    Full Text Available Both cutinase and lipase belong to the esterase group of enzymes (EC 3.1.1.X, which are capable of catalyzing the hydrolysis of ester bonds. Cutinase catalyzes the hydrolysis of cutin, an insoluble biopolyester which is the structural component of plant cuticles. As cutinase is an efficient catalyst in watery or organic media, it is potentially appropriate for the detergent, food and cosmetic industries. The objective of this work was to isolate microorganisms from plants and perform a pre-selection of molds showing esterase producing ability. The selected strains were then submitted to fermentation in media containing cutin. The lipolytic and cutinolytic activities of the supernatant were determined in order to differentiate lipase producers from cutinase-producing strains. The mold strain selected as the best cutinase producer was identified as being Fusarium oxysporium.A cutinase pertence, como as lípases, ao grupo das esterases (EC 3.1.1.X, que são enzimas capazes de catalisar reações de hidrólise de ligações do tipo éster. A cutinase catalisa a hidrólise da cutina, um biopoliéster insolúvel que constitui o componente estrutural da cutícula das plantas. Esta enzima tem se mostrado um eficiente catalisador tanto em solução aquosa quanto em meios orgânicos, sendo potencialmente apropriada para usos em indústria de detergentes, alimentos e cosméticos. O objetivo deste trabalho foi isolar fungos de diversas fontes e realizar uma pré-seleção destes, quanto à habilidade em produzir esterase. As linhagens fúngicas pré-selecionadas como produtoras de esterase foram inoculadas em meio de cultivo contendo cutina extraída de maçã. As atividades cutinolítica e lipolítica foram medidas no sobrenadante das culturas a fim de diferenciar os microrganismos produtores de lipase dos produtores de cutinase. Uma linhagem isolada mostrou a maior atividade cutinolítica após 12 dias de fermentação em um meio contendo 1% de cutina e

  18. Effect of γ-radiation on the production of aflatoxin B1 by Aspergillus parasiticus in raisins (Vitis vinifera L.)

    International Nuclear Information System (INIS)

    Aflatoxin B1 (AFB1) mostly produced by Aspergillus flavus and Aspergillus parasiticus, is an extremely toxic and carcinogenic metabolite. The effect of gamma irradiation at dose of 10 kGy on the production of aflatoxin B1 (AFB1) inoculated by Aspergillus parasiticus in raisins (Vitis vinifera L.) and on AFB1 in contaminated samples, was investigated. Values of the amount of aflatoxin B1 produced on the 12th day of incubation, after irradiation, showed that gamma radiation exposure at 10 kGy decreased AFB1 production at 65% compared with the non-irradiated sample, on the same day. The application of 10 kGy gamma radiation directly on 100 ng of AFB1 which were spiked in raisins resulted in ∼29% reduction of AFB1. According to the risk assessment analysis the Provisional Maximum Tolerable Daily Intake (PMTDI) of 1.0 ng AFB1 kg−1bw, indicates that consumers are less exposed to AFB1 from the irradiated raisins. - Highlights: • Aflatoxin B1 (AFB1) is an extremely toxic and carcinogenic metabolite. • AFB1 is produced in raisins. • Irradiation at the dose of 10 kGy affects AFB1 production. • 10 kGy reduced (∼65%) AFB1 production by A.parasiticus in raisins. • 10 kGy reduced (∼29%) AFB1 spiked directly in raisins

  19. Improved Enzyme Catalytic Characteristics upon Glutaraldehyde Cross-Linking of Alginate Entrapped Xylanase Isolated from Aspergillus flavus MTCC 9390

    Science.gov (United States)

    Bhushan, Bharat; Pal, Ajay; Jain, Veena

    2015-01-01

    Purified fungal xylanase was entrapped in alginate beads. Its further cross-linking using glutaraldehyde resulted in large enzyme aggregates which may function as both a catalyst and a support material for numerous substrate molecules. Enzyme cross-linking presented a negative impact on enzyme leaching during repeated washings and recovery of enzyme activity was substantial after twelve cycles of usage. The entrapment followed by cross-linking doubled the total bound activity and also greatly improved the enzyme stability at extreme chemical environment. The wide pH stability, better thermo- and storage stability, lowered Km value, and protection from some metal ions are salient achievements of present immobilization. The study shows the efficacy, durability, and sustainability of immobilized catalytic system which could be efficiently used for various juice processing operations. PMID:26347814

  20. 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. PMID:11414325

  1. Comparison of Etest with Modified Broth Microdilution Method for Testing Susceptibility of Aspergillus spp. to Voriconazole

    Science.gov (United States)

    Serrano, M. C.; Morilla, D.; Valverde, A.; Chávez, M.; Espinel-Ingroff, A.; Claro, R.; Ramírez, M.; Mazuelos, E. Martín

    2003-01-01

    We compared the Etest with a broth microdilution method, performed according to a modified National Committee for Clinical Laboratory Standards guideline (M38-A), for determining the in vitro susceptibility of 77 isolates of Aspergillus spp. (26 A. fumigatus, 21 A. flavus, 10 A. terreus, 9 A. niger, 5 A. nidulellus, 4 A. glaucus, and 2 A. flavipes isolates). Overall, there was 92.2% agreement between both methods when Etest MICs were read at 24 h and 83.1% agreement when both methods were read at 48 h. When Etest MICs were read at 24 h, the agreement was >90% for all species tested except for A. fumigatus (84.6%). When Etest MICs were read at 48 h, the agreement ranged from 50 to 100%. The poorest agreement was seen with A. glaucus (50%) and A. fumigatus (65%). Where a discrepancy was observed between Etest and the reference method, the Etest MIC was generally higher. The Etest appears to be a suitable alternative procedure for testing the susceptibility of Aspergillus spp. to voriconazole. PMID:14605181

  2. Retraction of colonies and structures of Aspergillus Spp. as a possible high dose sensor

    International Nuclear Information System (INIS)

    Changes in the length of macro-and microscopic structures of irradiated Aspergillus spp. colonies were investigated in this work in search for correlations with radiation dose. Effects related to growth and morphology produced by exposure to radiation doses ranging from 0.0 up to 8.0 kGy on strains of A. flavus (CMT 00079), A. parasiticus (CMT 00064) and A ochraceus (CMT 00145) were analyzed. Fungal colonies were inoculated on fresh peanut seeds and incubated for 5 days at 25°C. On the sixth day the samples were irradiated and moved to Petri dishes containing PDA culture medium where they remained incubated for 7 days at 25°C Post irradiation growth was periodically monitored by visual inspections and measurements of mycelial diameters. In addition, microscopic analyses were performed to determine the length of the major structures of the colonies. It has been found that irradiation causes a decrease in the diameter of colonies as well as in the length of microscopic structures of the fungus. The amount of retraction has been found to be strongly correlated to radiation dose. Such findings hint at the possibility of using in situ Aspergillus spp. colonies as high-dose living dosimeters in the event of massive radiation exposures. (author)

  3. Impact of water activity of diverse media on spore germination of Aspergillus and Penicillium species.

    Science.gov (United States)

    Nanguy, Sidjè Paule-Marina; Perrier-Cornet, Jean-Marie; Bensoussan, Maurice; Dantigny, Philippe

    2010-08-15

    The effects of water activity (a(w)) of diverse media i/ culture medium for sporogenesis, a(w sp) ii/ liquid spore suspension medium, a(w su) and iii/ medium for germination, a(w ge), on the germination time t(G) of Aspergillus carbonarius, Aspergillus flavus, Penicillium chrysogenum and Penicillium expansum were assessed according to a screening matrix at 0.95 and 0.99 a(w). It was shown that i/ reduced t(G)s were obtained at 0.95 a(w sp) except for P. expansum ii/ a significant effect of a(w su) on t(G) was demonstrated for A. carbonarius, P. chrysogenum and P. expansum iii/ the most important factor for controlling the germination time was the medium for germination except for A. carbonarius (a(w su)). In accordance with the fact that fungal spores can swell as soon as they are suspended in an aqueous solution it is recommended to re-suspend fungal spores in a solution at the same water activity as that of subsequent germination studies. PMID:20673593

  4. Identification of Aspergillus species in Central Europe able to produce G-type aflatoxins.

    Science.gov (United States)

    Baranyi, Nikolett; Despot, Daniela Jakšić; Palágyi, Andrea; Kiss, Noémi; Kocsubé, Sándor; Szekeres, András; Kecskeméti, Anita; Bencsik, Ottó; Vágvölgyi, Csaba; Klarić, Maja Šegvić; Varga, János

    2015-09-01

    The occurrence of potential aflatoxin producing fungi was examined in various agricultural products and indoor air in Central European countries including Hungary, Serbia and Croatia. For species identification, both morphological and sequence based methods were applied. Aspergillus flavus was detected in several samples including maize, cheese, nuts, spices and indoor air, and several isolates were able to produce aflatoxins. Besides, three other species of Aspergillus section Flavi, A. nomius, A. pseudonomius and A. parasiticus were also isolated from cheese, maize and indoor air, respectively. This is the first report on the occurrence of A. nomius and A. pseudonomius in Central Europe. All A. nomius, A. pseudonomius and A. parasiticus isolates were able to produce aflatoxins B1, B2, G1 and G2. The A. nomius isolate came from cheese produced very high amounts of aflatoxins (above 1 mg ml⁻¹). All A. nomius, A. pseudonomius and A. parasiticus isolates produced much higher amounts of aflatoxin G1 then aflatoxin B1. Further studies are in progress to examine the occurrence of producers of these highly carcinogenic mycotoxins in agricultural products and indoor air in Central Europe. PMID:26344029

  5. Retraction of colonies and structures of Aspergillus Spp. as a possible high dose sensor

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Valeria B., E-mail: valeriabborges@hotmail.com [Coordenacao dos Programas de Pos-Graduacao em Processos Quimicos e Bioquimicos (EQ/UFRJ), Rio de Janeiro, RJ (Brazil). Escola de Quimica; Vital, Helio C., E-mail: vital@ctex.eb.br [Centro Tecnologico do Exercito (DDQBN/CTEx), Rio de Janeiro, RJ (Brazil). Div. de Defesa Quimica, Biologica e Nuclear. Secao de Defesa Nuclear; Moraes, Aurea M.L., E-mail: ltbbf@ioc.fiocruz.br [Instituto Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, RJ (Brazil). Departamento de Micologia

    2013-07-01

    Changes in the length of macro-and microscopic structures of irradiated Aspergillus spp. colonies were investigated in this work in search for correlations with radiation dose. Effects related to growth and morphology produced by exposure to radiation doses ranging from 0.0 up to 8.0 kGy on strains of A. flavus (CMT 00079), A. parasiticus (CMT 00064) and A ochraceus (CMT 00145) were analyzed. Fungal colonies were inoculated on fresh peanut seeds and incubated for 5 days at 25°C. On the sixth day the samples were irradiated and moved to Petri dishes containing PDA culture medium where they remained incubated for 7 days at 25°C Post irradiation growth was periodically monitored by visual inspections and measurements of mycelial diameters. In addition, microscopic analyses were performed to determine the length of the major structures of the colonies. It has been found that irradiation causes a decrease in the diameter of colonies as well as in the length of microscopic structures of the fungus. The amount of retraction has been found to be strongly correlated to radiation dose. Such findings hint at the possibility of using in situ Aspergillus spp. colonies as high-dose living dosimeters in the event of massive radiation exposures. (author)

  6. Aspergillus infections in cystic fibrosis.

    Science.gov (United States)

    King, Jill; Brunel, Shan F; Warris, Adilia

    2016-07-01

    Patients with cystic fibrosis (CF) suffer from chronic lung infection and airway inflammation. Respiratory failure secondary to chronic or recurrent infection remains the commonest cause of death and accounts for over 90% of mortality. Bacteria as Staphylococcus aureus, Pseudomonas aeruginosa and Burkholderia cepacia complex have been regarded the main CF pathogens and their role in progressive lung decline has been studied extensively. Little attention has been paid to the role of Aspergillus spp. and other filamentous fungi in the pathogenesis of non-ABPA (allergic bronchopulmonary aspergillosis) respiratory disease in CF, despite their frequent recovery in respiratory samples. It has become more apparent however, that Aspergillus spp. may play an important role in chronic lung disease in CF. Research delineating the underlying mechanisms of Aspergillus persistence and infection in the CF lung and its link to lung deterioration is lacking. This review summarizes the Aspergillus disease phenotypes observed in CF, discusses the role of CFTR (cystic fibrosis transmembrane conductance regulator)-protein in innate immune responses and new treatment modalities. PMID:27177733

  7. Aspergillus mediastinitis after cardiac surgery

    Directory of Open Access Journals (Sweden)

    Marie-Josée Caballero

    2016-03-01

    Conclusion: The clinical features of postoperative Aspergillus mediastinitis may be paucisymptomatic, emphasizing the need for a low index of suspicion in cases of culture-negative mediastinitis or in indolent wound infections. In addition to surgical debridement, the central component of antifungal therapy should include amphotericin B or voriconazole.

  8. Transcriptional profiling of Aspergillus niger

    NARCIS (Netherlands)

    Veen, van der D.

    2009-01-01

    The industrially important fungus Aspergillus niger feeds naturally on decomposing plant material, of which a significant proportion is lipid. Examination of the A. niger genome sequence suggested that all proteins required for metabolic conversion of lipids are present, including 63 predicted lipas

  9. Identification of thermostable beta-xylosidase activities produced by Aspergillus brasiliensis and Aspergillus niger

    DEFF Research Database (Denmark)

    Pedersen, Mads; Lauritzen, H.K.; Frisvad, Jens Christian; Meyer, Anne S.

    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...

  10. 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; Meyer, Anne Boye Strunge

    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...

  11. Ochratoxin A-Produktion durch Aspergillus ochraceus

    OpenAIRE

    Mühlencoert, Ellen

    2006-01-01

    Ochratoxin A, one of the 5 most important mycotoxins in food safety, is produced by several Aspergillus and Penicillium strains growing on grain, grapes and coffee. OTA biosynthesis in Aspergillus spp. depends more on the complex interaction of diverse environmental conditions than on a single growth factor or even the genetic ability to produce OTA. No apparent connection between biomass and OTA production was observed. OTA production by Aspergillus ochraceus could be controlled by the pH of...

  12. Developmental regulators in Aspergillus fumigatus.

    Science.gov (United States)

    Park, Hee-Soo; Yu, Jae-Hyuk

    2016-03-01

    The filamentous fungus Aspergillus fumigatus is the most prevalent airborne fungal pathogen causing severe and usually fatal invasive aspergillosis in immunocompromised patients. This fungus produces a large number of small hydrophobic asexual spores called conidia as the primary means of reproduction, cell survival, propagation, and infectivity. The initiation, progression, and completion of asexual development (conidiation) is controlled by various regulators that govern expression of thousands of genes associated with formation of the asexual developmental structure conidiophore, and biogenesis of conidia. In this review, we summarize key regulators that directly or indirectly govern conidiation in this important pathogenic fungus. Better understanding these developmental regulators may provide insights into the improvement in controlling both beneficial and detrimental aspects of various Aspergillus species. PMID:26920882

  13. Identificação e características culturais de espécies do gênero Aspergillus isoladas de sementes de feijão no Estado da Paraíba Identification and cultural characteristics of Aspergillus species isolated in common bean seeds from Paraíba State, Brazil

    Directory of Open Access Journals (Sweden)

    Vanilde Benicio

    2003-04-01

    Full Text Available A partir de sementes de feijão (Phaseulus vulgaris armazenadas no estado da Paraíba, foram isolados os fungos Aspergillus flavus, A. fumigatus, A. lucknowensis, A.niger, A.ochraceus e A. parasiticus. Os fungos foram identificados com base nas características culturais exibidas em meio de Czapek-Agar e morfológicas através de microscópio ótico composto. No oitavo dia de crescimento em meio de BDA, cada espécie apresentou diferenças quanto à curva de crescimento, taxa de crescimento durante o período de incubação e diâmetro das colônias no oitavo dia de acordo com a procedência das amostras de sementes.The fungi Aspergillus flavus, A. fumigatus, A. lucknowensis, A.niger, A.ochraceus and A. parasiticus were isolated from common bean (Phaseolus vulgaris seeds produced and stored by growers in the State of Paraíba, Brazil. These fungi were identified according to cultural characteristics on Czapek-agar medium and the structures viewed under compound microscope. The development of each fungal species on Potato-Dextrose-Agar (PDA medium presented differences for colony diameter, curve and rate of growth according to the seed samples from which were obtained.

  14. Characteristics of 1,4-Dioxane Degradation by Xanthobacter flavus DT8%Xanthobacter flavus DT8降解二噁烷的特性研究

    Institute of Scientific and Technical Information of China (English)

    金小君; 陈东之; 朱润晔; 陈静; 陈建孟

    2012-01-01

    A strain DT8 was isolated from the activated sludge using culture enrichment technique, and subsequently identified as Xanthobacter flavus based on the analysis of morphological and physiological characteristics as well as cellular fatty acid composition and 16S rRNA sequence. X. flavus DT8 could effectively utilize 1,4-dioxane as the sole carbon and energy source, and was able to completely degrade 100 mg. L ^-1 substrate within 48 h. The values of biomass yield and energy discrepancy index were 0.62 g·g^-1 and 1.00, respectively, indicating that low energy share was dissipated. The optimum pH and temperature for 1,4-dioxane degradation were 7.0 and 34℃ , respectively. The degradation could also be performed in poor nutrition solution, e.g. the degradation ratio reached 65.6% even though in a 100-fold diluted medium. The induction process was not required in 1,4-dioxane degradation from this investigation. The characteristics of 1,4-dioxane degradation by X. flavus DT8 in direct metabolic mode was therefore revealed in this paper, and it will built a solid foundation for the application of biological purification of waste water and off-gas containing 1,4- dioxane.%对上海某医药厂污水站好氧池的活性污泥进行长期驯化,分离到1株能以二噁烷为唯一碳源和能源生长的菌株DT8.经生理生化、脂肪酸鉴定和16S rRNA序列分析,确定该菌株为黄黄色杆菌DT8(Xanthobacter flavus DT8).序批实验表明X.flavus DT8可于48 h内完全降解100 mg.L-1二噁烷,并可实现污染物的矿化.随着生物量的增加,该降解过程的细胞得率(以二噁烷计)为0.62 g.g-1,能量消耗系数(δe)为1.00,表明X.flavus DT8代谢二噁烷消耗的能量较少.研究不同温度、pH和营养条件对二噁烷降解的影响,发现二噁烷降解较适宜的温度和初始pH分别为34℃和7.0;在贫营养条件下,即无机盐培养基稀释100倍时,100 mg.L-1二噁烷于48 h的降解率达到65.6%.对X.flavus

  15. Regulatory processes in Aspergillus niger

    DEFF Research Database (Denmark)

    Poulsen, Lars

    Filamentous fungi are extensively used in the fermentation industry for synthesis of numerous products. One of the most important, is the fungus Aspergillus niger, used industrially for production of organic acids, and homologous as well as heterologous enzymes. This fungus has numerous of advant...... fumonisin production, identified. These formed the basis for the subsequent examinations, which resulted in the identification of azelaic acid, a plant hormone and a very potent fumonisin inducer....

  16. Germination of Aspergillus niger conidia

    OpenAIRE

    Hayer, Kimran

    2014-01-01

    Aspergillus niger is a black-spored filamentous fungus that forms asexual spores called conidospores (‘conidia’). Germination of conidia, leading to the formation of hyphae, is initiated by conidial swelling and mobilisation of endogenous carbon and energy stores, followed by polarisation and emergence of a hyphal germ tube. These morphological and biochemical changes which define the model of germination have been studied with the aim of understanding how conidia sense and utilise different...

  17. Transcriptional profiling of Aspergillus niger

    OpenAIRE

    Veen, van der, J.T.

    2009-01-01

    The industrially important fungus Aspergillus niger feeds naturally on decomposing plant material, of which a significant proportion is lipid. Examination of the A. niger genome sequence suggested that all proteins required for metabolic conversion of lipids are present, including 63 predicted lipases. In contrast to polysaccharide-degrading enzyme networks, not much is known about the signaling and regulatory processes that control lipase expression and activity in fungi. This project was ai...

  18. Asexual Sporulation in Aspergillus nidulans

    OpenAIRE

    Adams, Thomas H; Wieser, Jenny K.; Yu, Jae-Hyuk

    1998-01-01

    The formation of mitotically derived spores, called conidia, is a common reproductive mode in filamentous fungi, particularly among the large fungal class Ascomycetes. Asexual sporulation strategies are nearly as varied as fungal species; however, the formation of conidiophores, specialized multicellular reproductive structures, by the filamentous fungus Aspergillus nidulans has emerged as the leading model for understanding the mechanisms that control fungal sporulation. Initiation of A. nid...

  19. The Volatome of Aspergillus fumigatus

    OpenAIRE

    Heddergott, C.; Calvo, A. M.; Latgé, J P

    2014-01-01

    Early detection of invasive aspergillosis is absolutely required for efficient therapy of this fungal infection. The identification of fungal volatiles in patient breath can be an alternative for the detection of Aspergillus fumigatus that still remains problematic. In this work, we investigated the production of volatile organic compounds (VOCs) by A. fumigatus in vitro, and we show that volatile production depends on the nutritional environment. A. fumigatus produces a multiplicity of VO...

  20. Investigation of malic acid production in Aspergillus oryzae under nitrogen starvation conditions.

    Science.gov (United States)

    Knuf, Christoph; Nookaew, Intawat; Brown, Stephen H; McCulloch, Michael; Berry, Alan; Nielsen, Jens

    2013-10-01

    Malic acid has great potential for replacing petrochemical building blocks in the future. For this application, high yields, rates, and titers are essential in order to sustain a viable biotechnological production process. Natural high-capacity malic acid producers like the malic acid producer Aspergillus flavus have so far been disqualified because of special growth requirements or the production of mycotoxins. As A. oryzae is a very close relative or even an ecotype of A. flavus, it is likely that its high malic acid production capabilities with a generally regarded as safe (GRAS) status may be combined with already existing large-scale fermentation experience. In order to verify the malic acid production potential, two wild-type strains, NRRL3485 and NRRL3488, were compared in shake flasks. As NRRL3488 showed a volumetric production rate twice as high as that of NRRL3485, this strain was selected for further investigation of the influence of two different nitrogen sources on malic acid secretion. The cultivation in lab-scale fermentors resulted in a higher final titer, 30.27 ± 1.05 g liter(-1), using peptone than the one of 22.27 ± 0.46 g liter(-1) obtained when ammonium was used. Through transcriptome analysis, a binding site similar to the one of the Saccharomyces cerevisiae yeast transcription factor Msn2/4 was identified in the upstream regions of glycolytic genes and the cytosolic malic acid production pathway from pyruvate via oxaloacetate to malate, which suggests that malic acid production is a stress response. Furthermore, the pyruvate carboxylase reaction was identified as a target for metabolic engineering, after it was confirmed to be transcriptionally regulated through the correlation of intracellular fluxes and transcriptional changes. PMID:23892740

  1. Liver injury in invasive aspergillus. Echographic findings

    International Nuclear Information System (INIS)

    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

  2. Uma heurística de busca tabu simples para o problema de carregamento de paletes do produtor

    Directory of Open Access Journals (Sweden)

    Vitória Pureza

    2003-08-01

    Full Text Available O problema de carregamento de paletes do produtor consiste em arranjar, ortogonalmente e sem sobreposição, o máximo número de caixas de dimensões (l,w ou (w,l, sobre um palete retangular de dimensões (L,W. Este problema vem sendo tratado com sucesso por heurísticas de blocos, onde são gerados padrões de carregamento compostos por um ou mais blocos, cujas peças possuem a mesma orientação. Uma característica desses métodos é que os padrões gerados estão limitados aos chamados padrões não-guilhotinados de primeira ordem. Neste trabalho é proposta uma abordagem baseada na incorporação de busca tabu simples (sem estruturas de memória de longo prazo em heurísticas de bloco. Partindo-se de uma solução inicial, são realizados movimentos de aumento de blocos, que resultam na diminuição, eliminação e criação de outros blocos. Resultados computacionais indicam que esta abordagem é capaz de gerar padrões ótimos de ordem superior em problemas de difícil resolução para outros métodos da literatura.The manufacturer's pallet loading problem consists in arranging, orthogonally and without overlapping, the maximum number of boxes with dimensions (l,w or (w,l onto a rectangular pallet with dimensions (L,W. This problem has been handled successfully by block heuristics, which generate loading patterns composed by one or more blocks where the pieces have the same orientation. A feature of such methods is that the patterns are limited to the so called 1st order non-guillotine patterns. In this work we propose an approach based on the incorporation of simple tabu search (without longer term memory structures in block heuristics. Starting from an initial pattern, the algorithm performs moves that increase the size of selected blocks in the current pattern; as a result, other blocks are decreased, eliminated or created. Computational results indicate that the approach is capable of generating superior order optimal patterns for

  3. Two novel species of Aspergillus section Nigri from indoor air

    Science.gov (United States)

    Aspergillus collinsii, Aspergillus floridensis, and Aspergillus trinidadensis are described as novel uniseriate species of Aspergillus section Nigri isolated from air samples. To describe the species we used phenotypes from 7-d Czapek yeast extract agar culture (CYA) and malt extract agar culture (M...

  4. Aspergillus Osteomyelitis of the Skull.

    Science.gov (United States)

    Nicholson, Simon; King, Richard; Chumas, Paul; Russell, John; Liddington, Mark

    2016-07-01

    Osteomyelitis of the craniofacial skeleton is rare, with fungal pathogens least commonly implicated. The authors present 2 patients of osteomyelitis of the skull caused by Aspergillus spp. and discuss the diagnosis, clinicopathological course, and management strategies.Late recurrence seen in this type of infection warrants long-term follow-up and a high index of suspicion for the clinical signs associated with recurrence.Such patients would benefit from their surgical debridement being planned and managed via a specialist craniofacial unit, so as to utilize the most aesthetically sensitive approach and the experience of specialists from several surgical disciplines. PMID:27391523

  5. Ribonuclease Production by Aspergillus species

    OpenAIRE

    Eleni Gomes; Roberto da Silva; Alcides Serzedello

    1998-01-01

    Ribonuclease production by Aspergillus flavipes, A. sulphureus and A. fischeri in semi-synthetic medium, after 24-144 hours at 30ºC under shaking, was studied. After cultivation, the medium was separated from micelia by filtration and the resultant solution was used as enzymatic extract. The highest amount of biomass and RNase was obtained after 96 hours of cultivation. The enzymes produced by three species presented similar characteristics, with optimum temperature at 55ºC and two peaks of a...

  6. Rapid detection of aflatoxigenic Aspergillus sp. in herbal specimens by a simple, bendable, paper-based lab-on-a-chip.

    Science.gov (United States)

    Chaumpluk, Piyasak; Plubcharoensook, Pattra; Prasongsuk, Sehanat

    2016-06-01

    Postharvest herbal product contamination with mycotoxins and mycotoxin-producing fungi represents a potentially carcinogenic hazard. Aspergillus flavus is a major cause of this issue. Available mold detection methods are PCR-based and rely heavily on laboratories; thus, they are unsuitable for on-site monitoring. In this study, a bendable, paper-based lab-on-a-chip platform was developed to rapidly detect toxigenic Aspergillus spp. DNA. The 3.0-4.0 cm(2) chip is fabricated using Whatman™ filter paper, fishing line and a simple plastic lamination process and has nucleic acid amplification and signal detection components. The Aspergillus assay specifically amplifies the aflatoxin biosynthesis gene, aflR, using loop-mediated isothermal amplification (LAMP); hybridization between target DNA and probes on blue silvernanoplates (AgNPls) yields colorimetric results. Positive results are indicated by the detection pad appearing blue due to dispersed blue AgNPls; negative results are indicated by the detection pad appearing colorless or pale yellow due to probe/target DNA hybridization and AgNPls aggregation. Assay completion requires less than 40 min, has a limit of detection (LOD) of 100 aflR copies, and has high specificity (94.47%)and sensitivity (100%). Contamination was identified in 14 of 32 herbal samples tested (43.75%). This work demonstrates the fabrication of a simple, low-cost, paper-based lab-on-a-chip platform suitable for rapid-detection applications. PMID:27168276

  7. In vitro susceptibility testing of Candida and Aspergillus spp. to voriconazole and other antifungal agents using Etest: results of a French multicentre study.

    Science.gov (United States)

    Mallié, M; Bastide, J M; Blancard, A; Bonnin, A; Bretagne, S; Cambon, M; Chandenier, J; Chauveau, V; Couprie, B; Datry, A; Feuilhade, M; Grillot, R; Guiguen, C; Lavarde, V; Letscher, V; Linas, M D; Michel, A; Morin, O; Paugam, A; Piens, M A; Raberin, H; Tissot, E; Toubas, D; Wade, A

    2005-04-01

    Minimum inhibitory concentrations (MICs) of the antifungal agent voriconazole were determined using the Etest and compared with those of amphotericin B, itraconazole and fluconazole using 1986 clinical isolates of Candida spp. Voriconazole MICs were also compared with those of amphotericin B and itraconazole using 391 clinical isolates of Aspergillus spp. Voriconazole was found to have more potent activity and lower MIC values than amphotericin B, itraconazole and fluconazole against C. albicans, C. tropicalis, C. parapsilosis and C. kefyr. Against C. glabrata and C. krusei, voriconazole was more active than either of the other two azole antifungals but had similar activity to amphotericin B. For species of Aspergillus, MIC values of voriconazole were lower than those of amphotericin B and itraconazole against A. fumigatus and A. flavus, and were similar to those of amphotericin B against A. niger. Against A. terreus, MIC values for voriconazole and itraconazole were similar. A. terreus is known to be resistant to amphotericin B, and this was reflected in higher MIC values compared with those of voriconazole and itraconazole. Voriconazole therefore compares very favourably with other antifungal agents against a large number of clinical isolates of Candida and Aspergillus spp. PMID:15784312

  8. Molecular and functional characterization of a second copy of the aflatoxin regulatory gene, aflR-2, from Aspergillus parasiticus.

    Science.gov (United States)

    Cary, Jeffrey W; Dyer, John M; Ehrlich, Kenneth C; Wright, Maureen S; Liang, Shun-Hsin; Linz, John E

    2002-07-19

    The genes required for the synthesis of aflatoxin (AF) in Aspergillus flavus and Aspergillus parasiticus have been shown to be clustered on a chromosome in these fungi. Transcription of most of these genes is dependent upon the activity of the aflR gene, also present on the gene cluster, which encodes a zinc binuclear cluster DNA-binding protein. While many strains of A. parasiticus have only one copy of aflR (aflR-1), many others contain a second copy of this gene (aflR-2) which resides on a duplicated region of the aflatoxin gene cluster. Targeted disruption of aflR-1 generated a number of non-aflatoxin producing transformants of A. parasiticus SU-1 which still harbored a wild-type aflR-2 gene. Southern and Northern hybridization analyses and ELISA assays demonstrated that aflR-1 had been successfully inactivated in strain AFS10. DNA sequence analysis showed that aflR-2 was capable of encoding a deduced 47 kDa protein. Northern and RT-PCR analysis of RNA from a toxin producing strain indicated that aflR-2 was transcribed at extremely low levels compared to aflR-1. RT-PCR analysis of RNA from AFS10 demonstrated that mRNAs of aflatoxin pathway genes were not processed to their mature forms. Functional analysis of aflr-2 protein in a yeast system showed that it was not activating transcription. PMID:12084578

  9. Biological control of mycotoxin-producing molds Controle biológico de fungos de armazenamento produtores de micotoxinas

    Directory of Open Access Journals (Sweden)

    Flávio Henrique Vasconcelos de Medeiros

    2012-10-01

    , mas a maioria deles se baseia no uso de fungicidas. Embora os produtos químicos sejam, muitas vezes, a primeira estratégia de defesa contra fungos micotoxigênicos, o uso indiscriminado de fungicidas vem despertando a percepção pública, em razão de seus efeitos nocivos sobre o meio ambiente e à saúde humana/animal. Assim, existe uma crescente pressão pública em busca de alternativas mais segura e não nocivas ao meio ambiente para controlar estes organismos. Nesse contexto, o controle biológico utilizando antagonistas microbianos, tais como bactérias, fungos e leveduras têm mostrado ser um substituto viável para reduzir a utilização de produtos químicos. Apesar dos resultados positivos, usando os agentes de controle biológico, poucos produtos apenas foram registrados e estão comercialmente disponíveis para controlar fungos produtores de micotoxinas. Esta revisão traz estratégias de controle biológico para evitar ou reduzir danos em commodities agrícolas causadas por fungos de armazenamento e a contaminação de alimentos e rações por micotoxinas.

  10. 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

    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. Aspergill...... atypical strains of Aspergillus aculeatus, CBS 114.80 and CBS 620.78, and was isolated from grape berries in Portugal, Italy, France, Israel, Greece and Spain. The type strain of Aspergillus uvarum sp. nov. is IMI 388523(T)=CBS 127591(T)= ITEM 4834(T)= IBT26606(T)....

  11. Phylogeny and subgeneric taxonomy of Aspergillus

    DEFF Research Database (Denmark)

    Peterson, S.W.; Varga, Janos; Frisvad, Jens Christian; Samson, Robert A.

    The phylogeny of the genus Aspergillus and its teleomorphs is discussed based on multilocus sequence data. DNA sequence analysis was used to formulate a nucleotide sequence framework of the genus and to analyze character changes in relationship to the phylogeny hypothesized from the DNA sequence...... analysis. The sequence data used to delimitate subgeneric taxa included partial calmodulin, rDNA and RNA polymerase gene sequences. In our phylogenic structure of Aspergillus extrolite data of the various Aspergillus taxa collected from ex-type cultures and numerous other isolates are also discussed. A new...... subgeneric classification is proposed which includes 8 subgenera and 22 sections within the Aspergillus genus. Characteristics of these taxa are shortly discussed in this chapter....

  12. Putative virulence factors of Aspergillus fumigatus

    NARCIS (Netherlands)

    Tomee, JFC; Kauffman, HF

    2000-01-01

    Various putative virulence factors of Aspergillus fumigatus have been studied over the past decades. A. fumigatus gliotoxin is a potent inhibitor of the mucociliary system. Several fungal metabolites interfere with phagocytosis and opsonization including toxins, 'conidial inhibitory factor', 'A. fum

  13. Comparison of the activities of amphotericin B, itraconazole, and voriconazole against clinical and environmental isolates of Aspergillus species

    Directory of Open Access Journals (Sweden)

    Richa Misra

    2011-01-01

    Full Text Available Background: Invasive fungal infections are a significant cause of morbidity and mortality in immunocompromised populations. Aims: To evaluate the susceptibility pattern of our isolates against amphotericin B, itraconazole, and voriconazole and to compare the antifungal activities of these agents with each other against the Aspergillus species tested. Settings and Design: A prospective study was designed to include clinical and environmental isolates of Aspergillus species. Materials and Methods: 420 sputum samples, 70 bronchoalveolar lavage fluids, 160 oral washings, and 47 environmental samples were collected. Direct microscopy by potassium hydroxide and lactophenol cotton blue mounts followed by culture on Sabourad`s dextrose agar (SDA was done. Susceptibility testing was performed by the broth microdilution technique as per Clinical Laboratory Standards Institute standards (M-38A. Additionally, all the isolates were also tested by the colorimetric microdilution technique using Alamar Blue dye. Statistical Analysis: It was done by the Chi-square test and Z-test using SPSS statistical software version 12.0. Results and Conclusion: Twenty-seven isolates (47.3% were recovered from patients with chronic bronchial asthma followed by fibrocavitary pulmonary tuberculosis in 9 (15.7%, allergic bronchopulmonary aspergillosis (ABPA in 6 cases (10.5%, bronchiectasis in 3 (5.2%, bronchogenic carcinoma in 5 (8.7% and those receiving radiotherapy for head and neck cancer 7 (12.2%. Thirteen environmental isolates were also included in the study. The most common isolate was A. fumigatus 28 (40%, followed by A. niger 22 (31%, A. flavus 13 (19%, and A. terreus 7(10%. All isolates were susceptible to amphotericin B, itraconazole, and voriconazole. Among the three agents tested, voriconazole exhibited lowest MICs (≤1 μg/ml against all Aspergillus species.

  14. 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; 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...

  15. Identificação do potencial amilolítico de linhagens mutantes do fungo filamentoso Aspergillus nidulans Identification of the amylolytic potential of mutant strains of the filamentous fungi Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    Izabel Aparecida Soares

    2010-09-01

    Full Text Available As amilases estão entre as mais importantes enzimas industriais, apresentando grande importância biotecnológica, principalmente na indústria alimentícia. Com o avanço no conhecimento das enzimas, a utilização dos fungos como fonte de enzimas vem adquirindo um status de destaque nas mais variadas áreas industriais e comerciais. Diante disso, o presente estudo procurou identificar a presença de atividade amilolítica em quatro linhagens do fungo filamentoso Aspergillus nidulans, selvagem, PAT, biA1methG1 e CLB3, utilizando dois meios distintos de cultura, BDA e Meio Completo a 2% amido, variando os tratamentos com adição ou não de glicose. Foram determinados o diâmetro médio da colônia, o diâmetro médio do halo e o Índice Enzimático. Como resultados, todas as linhagens testadas foram capazes de degradar o amido quando na ausência de glicose, porém o tratamento que obteve estatisticamente melhor crescimento e maior degradação do amido foi o MC sem glicose a 2% amido e a linhagem que se demonstrou potencialmente degradadora de amido foi o mutante CLB3. Conclui-se, portanto, que Aspergillus nidulans pode ser considerado como um produtor de amilases.The amylases are among the most important industrial enzymes showing great biotechnological importance, mainly in the food industry. Due to the advance knowledge in enzyme research, the use of fungi as source of enzymes has acquired a prominent status in most varied industrial and commercial areas. Thus, the present study tried to identify the presence of the amylolytic activity in four stains of filamentous fungi Aspergillus nidulans, selvagem, PAT, biA1methG1 and CLB3 by using two different culture means, PDA and Complete mean with 2% starch, varying the treatments with and without the addition of glucose. The colony average diameter, the halo average diameter, and the enzymatic index were determined. The results show that all strains tested were capable of degrading starch in the

  16. Discovery and analysis of an active long terminal repeat-retrotransposable element in Aspergillus oryzae.

    Science.gov (United States)

    Jie Jin, Feng; Hara, Seiichi; Sato, Atsushi; Koyama, Yasuji

    2014-01-01

    Wild-type Aspergillus oryzae RIB40 contains two copies of the AO090005001597 gene. We previously constructed A. oryzae RIB40 strain, RKuAF8B, with multiple chromosomal deletions, in which the AO090005001597 copy number was found to be increased significantly. Sequence analysis indicated that AO090005001597 is part of a putative 6,000-bp retrotransposable element, flanked by two long terminal repeats (LTRs) of 669 bp, with characteristics of retroviruses and retrotransposons, and thus designated AoLTR (A. oryzae LTR-retrotransposable element). AoLTR comprised putative reverse transcriptase, RNase H, and integrase domains. The deduced amino acid sequence alignment of AoLTR showed 94% overall identity with AFLAV, an A. flavus Tf1/sushi retrotransposon. Quantitative real-time RT-PCR showed that AoLTR gene expression was significantly increased in the RKuAF8B, in accordance with the increased copy number. Inverse PCR indicated that the full-length retrotransposable element was randomly integrated into multiple genomic locations. However, no obvious phenotypic changes were associated with the increased AoLTR gene copy number. PMID:24646755

  17. The use of a-methyl-D-glucoside, a synthetic analogue of maltose, as inducer of amylase by Aspergillus sp in solid-state and submerged fermentations

    Directory of Open Access Journals (Sweden)

    Moreira Fabiana G.

    2001-01-01

    Full Text Available The use of a methyl-D-glucoside (alphaMG, a synthetic analogue of maltose, as carbon source and inducer of amylase synthesis to several species of Aspergillus was studied in submerged and solid-state fermentations. Among a group of ten species, A. tamarii, A. fumigatus and A. flavus were able to produce biomass and high specific amylolytic activity in submerged cultures containing alphaMG as the only carbon source. In solid state fermentation, the enrichment of basal wheat bran or corn cob medium with alphaMG increased up to 3 times the production of amylases. In both submerged and solid state fermentations, alphaMG was more effective inducer of amylases than maltose and starch.

  18. Fumigant Antifungal Activity of Myrtaceae Essential Oils and Constituents from Leptospermum petersonii against Three Aspergillus Species

    Directory of Open Access Journals (Sweden)

    Il-Kwon Park

    2012-09-01

    Full Text Available Commercial plant essential oils obtained from 11 Myrtaceae plant species were tested for their fumigant antifungal activity against Aspergillus ochraceus, A. flavus, and A. niger. Essential oils extracted from Leptospermum petersonii at air concentrations of 56 × 10−3 mg/mL and 28 × 10−3 mg/mL completely inhibited the growth of the three Aspergillus species. However, at an air concentration of 14 × 10−3 mg/mL, inhibition rates of L. petersonii essential oils were reduced to 20.2% and 18.8% in the case of A. flavus and A. niger, respectively. The other Myrtaceae essential oils (56 × 10−3 mg/mL only weakly inhibited the fungi or had no detectable affect. Gas chromatography-mass spectrometry analysis identified 16 compounds in L. petersonii essential oil. The antifungal activity of the identified compounds was tested individually by using standard or synthesized compounds. Of these, neral and geranial inhibited growth by 100%, at an air concentration of 56 × 10−3 mg/mL, whereas the activity of citronellol was somewhat lover (80%. The other compounds exhibited only moderate or weak antifungal activity. The antifungal activities of blends of constituents identified in L. petersonii oil indicated that neral and geranial were the major contributors to the fumigant and antifungal activities.

  19. Rabia en Potos flavus identificados en el departamento de madre de dios, Perú

    Directory of Open Access Journals (Sweden)

    Elena Vargas-Linares

    2014-01-01

    Full Text Available El Potos flavus es un mamífero nocturno que habita en bosques neotropicales desde Centroamérica hasta Sudamérica. Se realizó un estudio de cuatro casos de rabia en Potos flavus ocurridos desde abril de 2012 en el departamento de Madre de Dios en Perú, captados como parte de la vigilancia epidemiológica. Los análisis realizados en el laboratorio de referencia regional de Madre de Dios determinaron presencia de antígeno del virus de la rabia en tres de las muestras de tejido encefálico, dichos resultados fueron corroborados en el Laboratorio de Zoonosis Virales del Instituto Nacional de Salud del Perú mediante inmunofluorescencia directa, la tipificación no identificó ninguna de las variantes conocidas en murciélagos o en perros. La ocurrencia de cuatro casos de rabia en Potos flavus suma evidencias de la emergencia de un nuevo reservorio del virus de la rabia y que ha sido reportada previamente en el mismo departamento el año 2007

  20. Rabia en Potos flavus identificados en el departamento de madre de dios, Perú

    Directory of Open Access Journals (Sweden)

    Elena Vargas-Linares

    2014-03-01

    Full Text Available El Potos flavus es un mamífero nocturno que habita en bosques neotropicales desde Centroamérica hasta Sudamérica. Se realizó un estudio de cuatro casos de rabia en Potos flavus ocurridos desde abril de 2012 en el departamento de Madre de Dios en Perú, captados como parte de la vigilancia epidemiológica. Los análisis realizados en el laboratorio de referencia regional de Madre de Dios determinaron presencia de antígeno del virus de la rabia en tres de las muestras de tejido encefálico, dichos resultados fueron corroborados en el Laboratorio de Zoonosis Virales del Instituto Nacional de Salud del Perú mediante inmunofluorescencia directa, la tipificación no identificó ninguna de las variantes conocidas en murciélagos o en perros. La ocurrencia de cuatro casos de rabia en Potos flavus suma evidencias de la emergencia de un nuevo reservorio del virus de la rabia y que ha sido reportada previamente en el mismo departamento el año 2007

  1. Um método heurístico baseado em relaxação Lagrangiana para o problema de carregamento de paletes do produtor

    Directory of Open Access Journals (Sweden)

    Farago Randal

    2000-01-01

    Full Text Available Neste trabalho desenvolvemos um método heurístico, baseado em relaxação Lagrangiana e surrogate, para resolver o problema de carregamento de paletes do produtor. Tal problema consiste em arranjar o máximo número de caixas por camada sobre o palete, otimizando, assim, o aproveitamento da superfície do palete. Aplicamos um método de redução do problema e uma heurística Lagrangiana no procedimento de otimização do subgradiente. Comparamos as soluções encontradas com soluções produzidas por outros métodos da literatura e com soluções utilizadas em situações práticas. Para isso, utilizamos dados obtidos na literatura e dados reais fornecidos por uma transportadora.

  2. Desempenho dos Arranjos Institucionais e Minimização dos Custos de Transação: transações entre produtores e fecularias de mandioca

    OpenAIRE

    Olivier Vilpoux

    2011-01-01

    No Brasil, a falta de competitividade do setor de fécula de mandioca em relação ao amido de milho é explicada pelas dificuldades em obter matériaprima – raízes de mandioca – em quantidades e preços estáveis. A resolução desses problemas envolve a adoção de arranjos institucionais que estabilizam as transações entre produtores e industriais. A análise de 37 fecularias permitiu avaliar as características das transações e o desempenho dos arranjos adotados, medido por meio da capacidade das empr...

  3. Prevalence and mechanism of triazole resistance in Aspergillus fumigatus in a referral chest hospital in Delhi, India and an update of the situation in Asia

    Directory of Open Access Journals (Sweden)

    Anuradha eChowdhary

    2015-05-01

    Full Text Available Aspergillus fumigatus causes varied clinical syndromes ranging from colonization to deep infections. The mainstay of therapy of Aspergillus diseases is triazoles but several studies globally highlighted variable prevalence of triazole resistance, which hampers the management of aspergillosis. We studied the prevalence of resistance in clinical A. fumigatus isolates during 4 years in a referral Chest Hospital in Delhi, India and reviewed the scenario in Asia and the Middle East. Aspergillus species (n=2117 were screened with selective plates for azole resistance. The isolates included 45.4% A. flavus, followed by 32.4% A. fumigatus, 15.6% Aspergillus species and 6.6% A. terreus. Azole resistance was found in only 12 (1.7% A. fumigatus isolates.These triazole resistant A. fumigatus (TRAF isolates were subjected to (a calmodulin and β tubulin gene sequencing (b in vitro antifungal susceptibility testing against triazoles using CLSI M38-A2 (c sequencing of cyp51A gene and real-time PCR assay for detection of mutations and (d microsatellite typing of the resistant isolates. TRAF harbored TR34/L98H mutation in 10 (83.3% isolates with a pan-azole resistant phenotype. Among the remaining 2 TRAF isolates, one had G54E and the other had three non-synonymous point mutations. The majority of patients were diagnosed as invasive aspergillosis followed by allergic bronchopulmonary aspergillosis and chronic pulmonary aspergillosis. The Indian TR34/L98H isolates had a unique genotype and were distinct from the Chinese, Middle East and European TR34/L98H strains. This resistance mechanism has been linked to the use of fungicide azoles in agricultural practices in Europe as it has been mainly reported from azole naïve patients. Reports published from Asia demonstrate the same environmental resistance mechanism in A. fumigatus isolates from two highly populated countries in Asia i.e., China and India and also from the neighboring Middle East.

  4. Índice de inovação: hierarquização dos produtores do arranjo produtivo local de fruticultura irrigada, estado do Ceará

    Directory of Open Access Journals (Sweden)

    Kilmer Coelho Campos

    2011-09-01

    Full Text Available Enquadrou-se a proposta de identificar e analisar grupos homogêneos de produtores com diferentes níveis produtivos e inovativos, possibilitando seu melhor desenvolvimento no arranjo produtivo local de fruticultura irrigada localizado nos municípios de Limoeiro do Norte e Russas, no estado do Ceará. Utilizou-se a técnica de análise fatorial para a definição dos fatores e a análise de agrupamentos para a formação dos grupos homogêneos. Constatou-se que o desenvolvimento do arranjo produtivo local de fruticultura irrigada da microrregião do Baixo Jaguaribe no estado do Ceará é sustentado por um grupo de produtores mais integrados e intensivos nos processos de produção, inovação, cooperação e aprendizado interativo e pelas relações desenvolvidas em termos locais.The proposal is to identify and analyze homogeneous groups of producers with different productive and innovations levels, to develop better in the arrangement productive horticulture place irrigated located in the Limoeiro do Norte and Russas cities, in Ceará state. The technical of factorial analysis was used for the definition of the factors and the analysis of groupings to form homogeneous groups. The development of the arrangement productive place of irrigated horticulture of Low Jaguaribe in Ceará state is sustained by a group of producers which are more integrated and intensive in the production processes, innovation, cooperation and interactive learning, and for the relationships developed in local terms.

  5. Ribonuclease Production by Aspergillus species

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    Eleni Gomes

    1998-09-01

    Full Text Available Ribonuclease production by Aspergillus flavipes, A. sulphureus and A. fischeri in semi-synthetic medium, after 24-144 hours at 30ºC under shaking, was studied. After cultivation, the medium was separated from micelia by filtration and the resultant solution was used as enzymatic extract. The highest amount of biomass and RNase was obtained after 96 hours of cultivation. The enzymes produced by three species presented similar characteristics, with optimum temperature at 55ºC and two peaks of activity at pH 4.5 and 7.0. A. flavipes RNases were more sensitive to temperature: 50% of the initial activity was lost after 1 hour at 70ºC. After this heat treatment, RNase of A. sulphureus lost 30% of this activity and that of A. fischeri only 16%. The nucleotides released by enzimatic hydrolysis of RNA were separated by ion exchange chromatography in a AG-1X8-formiate column and identified by paper chromatography. This procedure indicated that the raw enzymatic extract of Aspergillus flavipes is able to hydrolyze RNA, releasing 3'-nucleotides monophosphate at pH 4.5 and 3' and 5'-nucleotides monophosphate at pH 7.0 and 8.5. This result suggests that this strain produces two different types of RNase, one acidic and other alcaline, with different specificities.A produção de ribonucleases extracelulares pelos fungos Aspergillus flavipes, A. sulphureus e A. fischeri foi estudada em meio semi-sintético por períodos de 24 a 144 horas, em "shaker" a 30ºC. Após o cultivo, o meio foi separado da massa micelial por filtração, sendo o filtrado utilizado como solução enzimática bruta. As três espécies produziram maior quantidade de biomassa e ribonuclease após 96 horas de cultivo. O estudo das RNases como extrato enzimático bruto demonstrou que existe grande similaridade entre as enzimas das três espécies, com temperaturas ótimas de 55ºC e dois picos de atividade a pH 4,5 e a pH 7,0. A RNAse produzida pelo fungo A. flavipes demonstrou ser mais

  6. Neuroimaging features of cerebral aspergillus abscess: Case report

    Directory of Open Access Journals (Sweden)

    Jie Bai

    2015-06-01

    Conclusion: Cerebral aspergillus abscesses possess some degree neuroimaging features on traditional CT/MR imaging. Combined with patient's clinical history, CT/MRI examination could facilitate early diagnosis of aspergillus abscesses in central nervous system.

  7. Chemodiversity in the genus Aspergillus

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian; Larsen, Thomas Ostenfeld

    2015-01-01

    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...

  8. Aspergillus species: An emerging pathogen in onychomycosis among diabetics

    OpenAIRE

    Wijesuriya, T. M.; Kottahachchi, J.; T. D. C. P. Gunasekara; Bulugahapitiya, U.; K. N. P. Ranasinghe; Neluka Fernando, S. S.; M M Weerasekara

    2015-01-01

    Introduction: Approximately, 33% patients with diabetes are afflicted with onychomycosis. In the past, nondermatophyte molds have been regarded as opportunistic pathogens; recently, Aspergillus species are considered as emerging pathogens of toenail infections. In Sri Lanka, the prevalence of Aspergillus species in onychomycosis among diabetics is not well documented. Objective: To determine the proportion of Aspergillus onychomycosis, risk factors and knowledge among diabetics. Materials and...

  9. 21 CFR 866.3040 - Aspergillus spp. serological reagents.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Aspergillus spp. serological reagents. 866.3040... (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3040 Aspergillus spp. serological reagents. (a) Identification. Aspergillus spp. serological reagents are devices...

  10. 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; Samson, R.A.; Rossen, L.; Hoor-Suykerbuyk, M.; Visser, J.

    2001-01-01

    We examined nine Aspergillus japonicus isolates and 10 Aspergillus aculeatus isolates by using molecular and biochemical markers, including DNA sequences of the ITS1-5.8S rRNA gene-ITS2 region, restriction fragment length polymorphisms (RFLP), and secondary-metabolite profiles. The DNA sequence 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...

  11. Identification of a splicing coactivator gene that affects the production of ochratoxin a in Aspergillus carbonarius

    Directory of Open Access Journals (Sweden)

    Lígia Uno Lunardi

    2009-11-01

    Full Text Available Ochratoxin A is a mycotoxin produced by some fungi species. Among them, Aspergillus carbonarius is considered a powerful producer. Genes involved in the ochratoxin A biosynthesis pathway have been identified in some producer species. However, there are few studies that purpose to identify these genes in A. carbonarius. The use of insertion mutants to identify genes associated with certain properties has been increased in the literature. In this work, the region of T-DNA integration was investigated in one A. carbonarius ochratoxin-defective mutant previously obtained by Agrobacterium tumefaciens-mediated transformation, in order to find an association between interrupted gene and the biosynthesis of ochratoxin A. The integration occurred in a gene that possibly encodes a splicing coactivator protein. The analysis of the relative expression of the splicing coativator gene from A. carbonarius wild type strain in four different media showed high correlation between the transcript levels and the ochratoxin A production.A ocratoxina A é uma micotoxina frequentemente encontrada em uma grande variedade de produtos alimentares e apresenta efeitos nefrotóxicos e potencial carcinogênico para animais e humanos. É naturalmente produzida por algumas espécies fúngicas, como Aspergillus carbonarius, que é considerado um potente produtor. Apesar disso, o número de estudos que visam identificar genes que são essenciais para a biossíntese de ocratoxina em A. carbonarius é ainda reduzido. Um mutante de A. carbonarius com baixa produção de ocratoxina A previamente obtido por transformação mediada por Agrobacterium tumefaciens foi investigado com o objetivo de encontrar uma associação entre o gene interrompido e a biossíntese desta micotoxina. Os resultados mostraram a ocorrência de uma junção não exata entre o T-DNA e o DNA genômico do fungo durante o evento de integração. A integração do T-DNA no genoma do mutante T188 provocou dele

  12. A rare case of bilateral aspergillus endophthalmitis

    Science.gov (United States)

    Gupta, Saurabh; Loudill, Cameron; Tammara, Anita; Chow, Robert T.

    2015-01-01

    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 unknown iatrogenic seed

  13. A rare case of bilateral aspergillus endophthalmitis.

    Science.gov (United States)

    Gupta, Saurabh; Loudill, Cameron; Tammara, Anita; Chow, Robert T

    2015-01-01

    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 unknown iatrogenic seed

  14. 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

  15. Classificação do tomate por atacadistas e produtores Curitiba Classification of tomatoes by wholesalers and producers in Curitiba, Brazil

    Directory of Open Access Journals (Sweden)

    Luciana R Rodrigues

    2007-12-01

    Full Text Available Identificou-se o sistema efetivamente utilizado para classificação do tomate para mesa por atacadistas e produtores em Curitiba. Verificou-se também por que não são adotadas as normas legais de classificação. Foram entrevistados 11 atacadistas e 31 produtores de tomate que comercializam sua produção na CEASA Curitiba. Outros dois produtores foram entrevistados em suas propriedades e acompanhados desde a produção até a comercialização. Após tabulação dos dados calculou-se a porcentagem de entrevistados enquadrados em cada questão, em relação ao número total de entrevistados. Constatou-se que há mais de uma linguagem de classificação no mercado e embora não haja padrões de classificação, essas linguagens são compreendidas no momento da comercialização. Para os atacadistas da CEASA Curitiba, a classificação do tomate baseia-se nas cores e nos tamanhos dos frutos. Os frutos podem ser verdes, coloridos (ou pintados ou vermelhos (ou maduros e apresentar tamanho Extra 3A ou boca 5 (diâmetro maior que 7,5 cm, Extra 2A ou bocas 6 ou 7 (diâmetro entre 6,2 e 7,5 cm, Extra 1A ou bocas 8 ou 9 (diâmetro entre 4,8 e 6,2 cm. Os frutos Extra 2A (médios são os mais freqüentes no comércio. Já a maioria dos produtores classifica os frutos em graúdos, médios e miúdos, em uma clara correspondência com a classificação adotada pelos atacadistas. Ambos os sistemas de classificação diferem do oficial que, segundo a maioria de atacadistas e produtores, é difícil de aplicar, encareceria o produto final e levaria a um aumento considerável do volume de frutos a serem descartados. Por esses motivos, antes que as normas oficiais de classificação de tomate possam ser adotadas, é necessário que se disponibilizem para o setor produtivo tecnologias de produção e assistência técnica qualificada. É necessário ainda que as normas de classificação sejam internalizadas pelos agentes do mercado por meio de cursos e

  16. Aspergillus species: An emerging pathogen in onychomycosis among diabetics

    Science.gov (United States)

    Wijesuriya, T. M.; Kottahachchi, J.; Gunasekara, T. D. C. P.; Bulugahapitiya, U.; Ranasinghe, K. N. P.; Neluka Fernando, S. S.; Weerasekara, M. M.

    2015-01-01

    Introduction: Approximately, 33% patients with diabetes are afflicted with onychomycosis. In the past, nondermatophyte molds have been regarded as opportunistic pathogens; recently, Aspergillus species are considered as emerging pathogens of toenail infections. In Sri Lanka, the prevalence of Aspergillus species in onychomycosis among diabetics is not well documented. Objective: To determine the proportion of Aspergillus onychomycosis, risk factors and knowledge among diabetics. Materials and Methods: This was descriptive cross-sectional study. Three hundred diabetic patients were included. Clinical examinations of patients’ toenails were performed by a clinical microbiologist. Laboratory identification was done, and pathogens were identified to the species level by morpho-physiological methods. All inferential statistics were tested at P onychomycosis. Aspergillus species were most commonly isolated n = 180 (71%) followed by dermatophytes, yeasts, and other molds n = 75 (29%). Of the patients having Aspergillus onychomycosis, 149 (83%) were in the > age group. In men, Aspergillus onycomycosis was seen in 82%. Among patients who had Aspergillus nail infection, 114 (63%) had diabetes for a period of > years. Among patients who were engaged in agricultural activities, 77% were confirmed to have infected nails due to Aspergillus species. Conclusion: Aspergillus niger was the most common pathogen isolated from toenail infection. Aspergillus species should be considered as an important pathogen in toenail onychomycosis in diabetic patients. Risk factors associated with Aspergillus onychomycosis were age, gender, duration of diabetes, length of exposure to fungi, and occupation. PMID:26693433

  17. Biocontrol of Aspergillus species on peanut kernels by antifungal diketopiperazine producing Bacillus cereus associated with entomopathogenic nematode.

    Directory of Open Access Journals (Sweden)

    Sasidharan Nishanth Kumar

    Full Text Available The rhabditid entomopathogenic nematode associated Bacillus cereus and the antifungal compounds produced by this bacterium were evaluated for their activity in reducing postharvest decay of peanut kernels caused by Aspergillus species in in vitro and in vivo tests. The results showed that B. cereus had a significant effect on biocontrol effectiveness in in vitro and in vivo conditions. The antifungal compounds produced by the B. cereus were purified using silica gel column chromatography and their structure was elucidated using extensive spectral analyses. The compounds were identified as diketopiperazines (DKPs [cyclo-(L-Pro-Gly, cyclo(L-Tyr-L-Tyr, cyclo-(L-Phe-Gly and cyclo(4-hydroxy-L-Pro-L-Trp]. The antifungal activities of diketopiperazines were studied against five Aspergillus species and best MIC of 2 µg/ml was recorded against A. flavus by cyclo(4-hydroxy-L-Pro-L-Trp. To investigate the potential application of cyclo(4-hydroxy-L-Pro-L-Trp to eliminate fungal spoilage in food and feed, peanut kernels was used as a food model system. White mycelia and dark/pale green spores of Aspergillus species were observed in the control peanut kernels after 2 days incubation. However the fungal growth was not observed in peanut kernels treated with cyclo(4-hydroxy-L-Pro-L-Trp. The cyclo(4-hydroxy-L-Pro-L-Trp was nontoxic to two normal cell lines [fore skin (FS normal fibroblast and African green monkey kidney (VERO] up to 200 µg/ml in MTT assay. Thus the cyclo(4-hydroxy-L-Pro-L-Trp identified in this study may be a promising alternative to chemical preservatives as a potential biopreservative agent which prevent fungal growth in food and feed. To the best of our knowledge, this is the first report demonstrating that the entomopathogenic nematode associated B. cereus and cyclo(4-hydroxy-L-Pro-L-Trp could be used as a biocontrol agents against postharvest fungal disease caused by Aspergillus species.

  18. 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

  19. The Production of Itaconic Acid from Sweet Potato Peel Using Aspergillus niger and Aspergillus terreus

    OpenAIRE

    OMOJASOLA PATRICIA FOLAKEMI; ADENIRAN EUNICE ADERONKE

    2014-01-01

    Accumulation of large quantities of agricultural residues results in deterioration of the environment and biomass loss which could be processed to yield value-added products like fuels and a variety of acids. The quest for a solution led to the fermentation of Ipomoea batatas using fungi. Aspergillus niger (ATCC 16404) and Aspergillus terreus (ATCC 20542) were used to ferment sweet potato peel (SPP), an agro-based waste. The physico-chemical analysis of the SPP was carried out. SPP was dried...

  20. Response of Tridens flavus (L.) A. S. Hitchc. to soil nutrients and disturbance in an early successional old field

    Science.gov (United States)

    Honu, Y.A.K.; Gibson, D.J.; Middleton, B.A.

    2006-01-01

    Soil nutrients and disturbance are two of the main abiotic factors that influence plant dominance (canopy cover), density, and fecundity in early successional old field plant communities. The manner in which the dominant species in old field successional systems respond to the interaction of nutrients and disturbance is poorly known. We examined the dominance, density of flowering tillers, and reproductive output of Tridens flavus, a perennial, warm-season bunchgrass that is important in old field succession, to varying soil nutrient and disturbance regimes. We tested the hypothesis that the interaction between nutrients and disturbance would influence the performance (cover, density, fecundity) of T. flavus. To test this hypothesis, we subjected 25 m2 experimental plots to various combinations of fertilizer and mowing treatments for eight years after initially plowing the field. The performance of T. flavus was measured by estimating percent cover for 8 years (1996-2003) and both density of flowering tillers and reproductive output (panicle length and number of branches per panicle) for three years (2001-2003). The pattern of canopy cover of T. flavus over the first eight years of succession varied over time depending on mowing regime. Dominance was significantly higher in plots that were fertilized only in years one and five than in annually fertilized and unfertilized control plots. The length of panicles and density of flowering tillers were both significantly greater in annually mowed plots than in unmowed plots. In the absence of mowing in particular, T. flavus became overtopped by woody species and declined in this old field community. Therefore, disturbances such as mowing and fertilization may be important in maintaining grasses such as Tridens flavus in old fields.

  1. 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

  2. Lignin-Modifying Enzymes of Flavodon flavus, a Basidiomycete Isolated from a Coastal Marine Environment†

    OpenAIRE

    Raghukumar, C.; D’Souza, T. M.; Thorn, R. G.; Reddy, C A

    1999-01-01

    A basidiomycetous fungus Flavodon flavus (Klotzsch) Ryvarden (strain 312), isolated from decaying sea grass from a coral lagoon off the west coast of India, mineralized nearly 24% of 14C-labeled synthetic lignin to 14CO2 in 24 days. When grown in low-nitrogen medium (2.4 mM N) this fungus produced three major classes of extracellular lignin-modifying enzymes (LMEs): manganese-dependent peroxidase (MNP), lignin peroxidase (LIP), and laccase. Low MNP and laccase activities were seen in high-nit...

  3. New species in Aspergillus section Terrei

    DEFF Research Database (Denmark)

    Samson, R. A.; Peterson, S. W.; Frisvad, Jens Christian;

    2011-01-01

    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...

  4. Organic acid production by Aspergillus niger

    DEFF Research Database (Denmark)

    Jongh, Wian de

    2006-01-01

    . Specielt Aspergillus niger er interessant i forbindelse med produktion af organiske syrer, idet denne organisme tolerer lavt pH, kan give høje produktudbytter, og kan give høje produktiviteter som allerede illustreret i anvendelsen af denne organisme i produktionen af citronsyre. Disse faktorer gør A...

  5. Phylogeny and subgeneric taxonomy of Aspergillus

    DEFF Research Database (Denmark)

    Peterson, S.W.; Varga, Janos; Frisvad, Jens Christian;

    2008-01-01

    The phylogeny of the genus Aspergillus and its teleomorphs is discussed based on multilocus sequence data. DNA sequence analysis was used to formulate a nucleotide sequence framework of the genus and to analyze character changes in relationship to the phylogeny hypothesized from the DNA sequence...

  6. ASPERGILLUS BOMBYCIS GENOTYPES (RFLP) FROM SILKWORM CULTIVATION

    Science.gov (United States)

    Eighteen isolates of Aspergillus bombycis from samples of dust, insect frass, and soil collected from 8 silkworm rearing facilities in Japan, as well as single silkworm rearing facilities in Indonesia and Malaysia, were subjected to DNA fingerprinting. PstI digests of total genomic DNA from each is...

  7. Comparação de indicadores de desempenho de produtores de leite localizados dentro e fora de assentamentos de reforma agrária no Triângulo Mineiro

    Directory of Open Access Journals (Sweden)

    Diana Hunt

    2009-03-01

    Full Text Available Na discussão sobre uma reforma agrária no Brasil, um ponto central é a competitividade dos assentamentos. Por isso, este estudo comparativo entre produtores leiteiros localizados dentro e fora dos assentamentos de reforma agrária busca ampliar a compreensão do potencial econômico e técnico dos assentados. A pesquisa perfaz 81 entrevistas: com 39 produtores de leite do assentamento "Rio das Pedras", no Triângulo Mineiro, com 42 produtores de leite fora do assentamento - nos municípios limítrofes de Uberlândia e Monte Alegre (MG. A pesquisa de campo foi feita entre abril e o início de junho de 2006, mas os dados se referem à produção, aos custos e à renda obtida no mês de março do mesmo ano. Foi recorrido a vários indicadores de desempenho econômico e técnico na produção de leite, como a margem bruta que corresponde à diferença entre receita e custo operacional. Os dados revelaram que a diferença entre as margens brutas médias por litro de leite dos produtores fora e dentro do assentamento é significativa, e a margem bruta média por litro de leite é maior para os produtores de fora do assentamento. A diferença nas margens brutas médias por litro de leite entre os produtores fora e dentro do assentamento resulta do preço por litro leite mais elevado obtido pelos grandes produtores de fora do assentamento. As maiores margens brutas totais foram encontradas entre produtores que produziram de 500 a 999 litros. As maiores margens brutas por litro de leite foram obtidas por médios ou pequenos produtores, inclusive assentados. Em ambos os grupos pesquisados, houve uma grande variação no desempenho. O conjunto dos indicadores de desempenho utilizados não aponta uma superioridade absoluta dos produtores de leite do entorno sobre os assentados. Produtores com desempenho fraco foram encontrados entre grandes e pequenos, independentemente de localização. Com esses resultados, recomenda-se a identificação e a implementa

  8. Two novel species of Aspergillus section Nigri from Thai coffee beans

    DEFF Research Database (Denmark)

    Noonim, Paramee; Mahakarnchanakul, Warapa; Varga, Janos; Frisvad, Jens Christian; Samson, Robert 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...

  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. Phylogeny, identification and nomenclature of the genus Aspergillus

    DEFF Research Database (Denmark)

    Samson, R.A.; Visagie, C.M.; Houbraken, J.;

    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...

  11. Antígenos nativos de Aspergillus fumigatus con utilidad para el inmunodiagnóstico de aspergiloma

    Directory of Open Access Journals (Sweden)

    José Casquero

    2009-04-01

    Full Text Available Con el objetivo de evaluar la utilidad de los antígenos nativos de cepas autóctonas de Aspergillus fumigatus para el inmunodiagnóstico de aspergiloma, se desarrolló un estudio empleando dos cepas de ese hongo, aisladas de pacientes con diagnóstico de aspergiloma (533 y 554, los cuales fueron confrontados con sueros controles comerciales de A. fumigatus, A. flavus, A. niger, Candida, Coccidioides, Histoplasma y Paracoccidioides mediante la prueba de inmunodifusión, asimismo, se evaluaron frente a 28 sueros de pacientes con sospecha de aspergiloma. Además, se realizó la caracterización de los componentes proteicos de los antígenos nativos con la técnica de SDS-PAGE y se confrontaron con diez sueros de pacientes con aspergiloma, paracoccidioidomicosis, histoplasmosis, proteína C reactiva e hidatidosis y suero de persona sana por inmunoblot. Se encontró una buena concordancia (kappa 0,92 entre los antígenos 533 y 554, y algo menor de éstos con el antígeno comercial para A. fumigatus (kappa 0,73 y 0,81 para el 553 y 554; respectivamente. La banda de 97 kDa reaccionó sólo con sueros de pacientes con aspergiloma siendo inmunodominante.

  12. Risco de preço na comercialização da soja: uso de derivativos pelos produtores rurais de Maracaju-MS Price risk in marketing soybeans: use of derivatives by farmers from Maracaju-MS, Brazil

    Directory of Open Access Journals (Sweden)

    Alex Sandro Richter Won Mühlen

    2013-05-01

    Full Text Available O presente trabalho analisou o comportamento do produtor de soja de Maracaju-MS quanto ao risco de preço e ao uso de derivativos agropecuários, buscando identificar os mecanismos de proteção de preço utilizados e as razões de seu uso ou rejeição. Para tanto, um questionário foi aplicado a uma amostra de produtores de soja, sendo também entrevistados representantes de tradings, armazéns gerais, cooperativas, corretoras e agentes financeiros. Constatou-se que a utilização de ferramentas de proteção de preço é ainda pouco expressiva, já que apenas 11% dos produtores usam o Mercado Futuro (hedge e o Mercado de Opções, e 38% os utilizaram alguma vez. O principal mecanismo usado é o Mercado a Termo. Produtores que já usaram o Mercado Futuro (hedge e o de opções atuam em médias e grandes propriedades, têm nível de escolaridade alto e estão mais capitalizados. A baixa utilização dos derivativos (Futuros e Opções se dá, principalmente, pela falta de conhecimento e pela ausência de profissionais de confiança capazes de orientar os produtores.The present research analysed the behavior of the soybean farmer of Maracaju-MS, Brazil in relation to price risk and use of agricultural derivatives, seeking to identify the price protection mechanisms used and the reasons for their use or rejection. A questionnaire was applied to a sample of soybean farmers. Also, representatives of trading houses, storage plants, cooperatives, brokers and financial agents were interviewed. Results showed that the use of price protection tools is still scarce, as only 11% of farmers use future market price (hedge and the options market, and 38% have used them before. The main mechanism used is the forward market. Farmers who already have used futures market (hedge and options manage medium and large properties, have a high level of education and are better capitalized. The low use of derivatives (futures and options is mainly due to the lack of

  13. Aspergillus species: An emerging pathogen in onychomycosis among diabetics

    Directory of Open Access Journals (Sweden)

    T M Wijesuriya

    2015-01-01

    Full Text Available Introduction: Approximately, 33% patients with diabetes are afflicted with onychomycosis. In the past, nondermatophyte molds have been regarded as opportunistic pathogens; recently, Aspergillus species are considered as emerging pathogens of toenail infections. In Sri Lanka, the prevalence of Aspergillus species in onychomycosis among diabetics is not well documented. Objective: To determine the proportion of Aspergillus onychomycosis, risk factors and knowledge among diabetics. Materials and Methods: This was descriptive cross-sectional study. Three hundred diabetic patients were included. Clinical examinations of patients' toenails were performed by a clinical microbiologist. Laboratory identification was done, and pathogens were identified to the species level by morpho-physiological methods. All inferential statistics were tested at P age group. In men, Aspergillus onycomycosis was seen in 82%. Among patients who had Aspergillus nail infection, 114 (63% had diabetes for a period of > years. Among patients who were engaged in agricultural activities, 77% were confirmed to have infected nails due to Aspergillus species. Conclusion: Aspergillus niger was the most common pathogen isolated from toenail infection. Aspergillus species should be considered as an important pathogen in toenail onychomycosis in diabetic patients. Risk factors associated with Aspergillus onychomycosis were age, gender, duration of diabetes, length of exposure to fungi, and occupation.

  14. Restriction endonuclease analysis of Aspergillus fumigatus DNA.

    OpenAIRE

    Burnie, J P; Coke, A.; Matthews, R. C.

    1992-01-01

    AIMS: To develop a genome based DNA fingerprinting system for Aspergillus fumigatus mould. METHODS: DNA was extracted from 21 isolates obtained from eight patients with an aspergilloma. This was with a freeze-dried mycelial extract fragmented in liquid nitrogen. DNA was subsequently purified by phenol-chloroform extraction followed by ultracentrifugation on a caesium chloride gradient. The DNA was restricted by EcoRI and Xba I. RESULTS: All isolates were identical when cut by EcoRI; Xba I del...

  15. SYNTHESIS OF COPPER NANOPARTICLES BY ASPERGILLUS SPECIES

    OpenAIRE

    Kantabathini Venkata Pavani; Nandigam Srujana; Guntur Preethi; Tandale Swati

    2013-01-01

    Recent developments in the biosynthesis of nanomaterials have demonstrated the important role of microorganisms in nanotechnology. The organisms show a unique potential in environmentally friendly production and accumulation of nanoparticles with different shapes and sizes. The present study proposed a green process for synthesis of copper nanoparticles using Aspergillus species. Syntheses of copper nanoparticles were characterized by UV-visible spectroscopy. The extracellular synthesis of co...

  16. SYNTHESIS OF COPPER NANOPARTICLES BY ASPERGILLUS SPECIES

    Directory of Open Access Journals (Sweden)

    Kantabathini Venkata Pavani

    2013-06-01

    Full Text Available Recent developments in the biosynthesis of nanomaterials have demonstrated the important role of microorganisms in nanotechnology. The organisms show a unique potential in environmentally friendly production and accumulation of nanoparticles with different shapes and sizes. The present study proposed a green process for synthesis of copper nanoparticles using Aspergillus species. Syntheses of copper nanoparticles were characterized by UV-visible spectroscopy. The extracellular synthesis of copper nanoparticles was characterized by scanning electron microscopy and Transmission electron microscopy.

  17. L-histidine utilization in Aspergillus nidulans.

    OpenAIRE

    Polkinghorne, M A; Hynes, M J

    1982-01-01

    Histidase activity rather than uptake of L-histidine is the limiting factor for the utilization of histidine as the sole nitrogen source for Aspergillus nidulans. Histidine cannot act as the sole carbon source, and evidence is presented indicating that this is attributable to an inability to convert histidine to L-glutamate in vivo. It has been shown that this fungus lacks an active urocanase enzyme and that histidine is quantitatively converted to urocanate, which accumulates in the extracel...

  18. Degradation of melanin by Aspergillus fumigatus.

    OpenAIRE

    Luther, J P; Lipke, H.

    1980-01-01

    A strain of Aspergillus fumigatus from composted coffee and garden wastes utilized natural deproteinized insect, banana, hair, octopus, and synthetic tyrosine and dopa melanins as sole sources of carbon. With a sucrose supplement, degradation was essentially complete after 50 days in Czapek medium pH 6.5 at 30 degrees C. The catabolic rate differed for each substrate pigment, as did the molecular weight distribution of products accumulating in the medium. After incubation with L-[U-14C]melani...

  19. Aspergillus bertholletius sp. nov. from Brazil Nuts

    OpenAIRE

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

    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 beta-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 fol...

  20. Pectinolytic activity of Aspergillus section Nigri strains

    OpenAIRE

    Maciel, M. H. C.; Ottoni, C. A.; Santos, C.; Moreira, K.; Lima, Nelson; Motta, Cristina Souza

    2012-01-01

    Pectinases are a heterogeneous group of related enzymes that hydrolyze pectic substances present mostly in plants. Pectinases are produced by plants, fungi, yeasts and bacteria. Filamentous fungi are good producers of pectinolytic enzymes (e.g., exopolygalacturonase (exo-PG) and endopolygalacturonase (endo-PG) and Aspergillus niger is the most commonly used fungal species for industrial production of pectinolytic enzymes. The application of pectinolytic enzymes plays an importa...

  1. Aspectos de relevância econômica no fomento florestal a partir da percepção dos produtores rurais envolvidos Aspects of economic relevance in the forest promotion from the perception of the involved farmers

    Directory of Open Access Journals (Sweden)

    Paulo Rogério Soares de Oliveira

    2006-08-01

    Full Text Available Neste trabalho são analisados dados de relevância econômica referentes ao diagnóstico realizado com produtores rurais participantes do principal programa de fomento florestal no Estado do Espírito Santo. Na coleta de dados, utilizaram-se de entrevistas em profundidade e aplicação de questionários, antecedidos por pré-teste. Os dados foram tabulados e processados no Excel e Statistical Package for the Social Sciences (SPSS. A amostragem foi aleatória estratificada, sendo os critérios: a situação do contrato de fomento (finalizado e não-renovado, em andamento e finalizado e renovado; e b tamanho do estrato fundiário por município. Foram aplicados questionários a 235 produtores rurais, em 16 municípios de sete microrregiões capixabas, com uma intensidade amostral de 20,7%. O fomento florestal mostrou ser importante na composição da renda familiar dos produtores entrevistados, e os rendimentos do fomento podem ir além do término do vínculo contratual. O programa tem contribuído para o desenvolvimento de outras atividades na propriedade, em razão dos investimentos feitos a partir das receitas advindas do fomento e da importância dada pelos produtores rurais à silvicultura, pois 40,9%, 37,8% e 57,2% dos produtores nos três diferentes estratos informaram que a silvicultura com eucalipto é a atividade principal ou secundária na propriedade. Parte dos produtores, após finalizar o contrato, não abandona a atividade de silvicultura, o que, associado a outros fatores, vem fortalecendo o mercado produtor de madeira.In this work, economic relevant data referring to a diagnosis carried out with farmers involved in a forest promotion program in Espirito Santo State were analyzed. In-depth interviews and questionnaires preceded by a pre-test were used for data collection. The Stratified Random Sampling method was used with the following criteria: a current status of promotion contract (finished and not renewed; in progress and

  2. In-vitro Inhibition of Biofilm Formation in Candida albicans and Candida tropicalis by Heat Stable Compounds in Culture Filtrate of Aspergillus flavus

    OpenAIRE

    Bhattacharyya, Sayan; Gupta, Prashant; Banerjee, Gopa; Jain, Amita; Singh, Mastan

    2013-01-01

    Background: Invasive candidiasis, caused mostly by Candida albicans and C. tropicalis is one of the most common causes of bloodstream infection with a substantial attributable mortality. This disease is associated with formation of structured, multilayered microbial communities known as biofilms over indwelling devices. Treatment is rendered difficult owing to factors like poor drug penetration through biofilms and high cost of the available antifungal drugs. Hence there is imminent need of d...

  3. Comparative Reannotation of 21 Aspergillus Genomes

    Energy Technology Data Exchange (ETDEWEB)

    Salamov, Asaf; Riley, Robert; Kuo, Alan; Grigoriev, Igor

    2013-03-08

    We used comparative gene modeling to reannotate 21 Aspergillus genomes. Initial automatic annotation of individual genomes may contain some errors of different nature, e.g. missing genes, incorrect exon-intron structures, 'chimeras', which fuse 2 or more real genes or alternatively splitting some real genes into 2 or more models. The main premise behind the comparative modeling approach is that for closely related genomes most orthologous families have the same conserved gene structure. The algorithm maps all gene models predicted in each individual Aspergillus genome to the other genomes and, for each locus, selects from potentially many competing models, the one which most closely resembles the orthologous genes from other genomes. This procedure is iterated until no further change in gene models is observed. For Aspergillus genomes we predicted in total 4503 new gene models ( ~;;2percent per genome), supported by comparative analysis, additionally correcting ~;;18percent of old gene models. This resulted in a total of 4065 more genes with annotated PFAM domains (~;;3percent increase per genome). Analysis of a few genomes with EST/transcriptomics data shows that the new annotation sets also have a higher number of EST-supported splice sites at exon-intron boundaries.

  4. Avaliação sob risco da capacidade de pagamento por água bruta de produtores da Bacia do Jaguaribe (CE

    Directory of Open Access Journals (Sweden)

    Robério Telmo Campos

    2010-06-01

    Full Text Available Este estudo avalia a capacidade de pagamento, sob condições de risco, dos produtores rurais usuários de água bruta da bacia do Jaguaribe, no estado do Ceará. Levam-se em conta o sistema de irrigação - se privado ou público, o perímetro, o nível de consumo e as atividades produzidas. Os dados são de natureza primária, obtidos por meio da aplicação de 93 questionários junto a irrigantes privados e públicos. Como método de análise, usa-se a técnica de simulação Monte Carlo. Conclui-se que, para os irrigantes privados e públicos da amostra, a capacidade de pagamento (CP por água bruta apresenta valor médio negativo e que a maioria desses produtores não tem condição de pagar pelo uso da água, representando risco elevado às atividades desenvolvidas. Somente os irrigantes que registraram renda líquida (residual ou net-back, sob condições deterministas, maior que zero podem pagar o valor da tarifa atualmente cobrada pela Companhia de Gestão dos Recursos Hídricos (Cogerh com sobra de caixa ou baixo risco. Alguns irrigantes não têm possibilidade alguma de arcar com a tarifa atual. Os irrigantes públicos apresentaram maior CP comparados aos privados. A atividade pecuária foi a que registrou menor risco para arcar com a tarifa.This paper aims to evaluate the capacity of payment, under risk conditions, of the bulk water to the rural producers' users in Jaguaribe basin, State of Ceará. It was considered the aspects concerning whether the irrigation system is public or private, the location of the irrigation district, the level of consumption level and the activities being carried out. The data are primary, gathered by the application of 93 questionnaires to producers in private and public irrigation districts. As method of analysis, it is used the Monte Carlo simulation. We can conclude that for the sample of public and private irrigation farmers, the capacity of payment (CP for bulk water shows a negative average value

  5. Behavioural development, fat reserves and their association with productivity in Lasius flavus founding queens

    Science.gov (United States)

    Norman, V. C.; Pamminger, T.; Hughes, W. O. H.

    2016-04-01

    Reproduction-related behaviours are key components determining individual fitness. Many behavioural traits are linked, and such trait associations often affect fitness. Here, we combine behavioural and physiological data during two critical time points of founding queens (early and late nest-founding stage) in the claustral ant Lasius flavus to assess how these factors affect their initial productivity. We show that most behavioural traits, except brood care behaviour, are plastic during queen development and demonstrate that there are alternative behavioural pathways to achieve high productivity under standardised conditions. These results indicate that queens can utilise multiple behavioural trait combinations to maximise reproductive output at the earliest, and arguably most critical, time of colony foundation.

  6. The current status of species recognition and identification in Aspergillus

    Science.gov (United States)

    The genus Aspergillus is a large economically important genus of fungi. In agriculture, some of the 250 species in this genus cause disease in plants and animals and some also produce poisons (mycotoxins) in foods and feeds. Aspergillus is a major killer of immunosuppressed people, such as diabeti...

  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. 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

    2014-06-01

    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

  9. Mass balance of nutrients during the filling phase of two reservoirs of Sistema Produtor Alto Tietê (SPAT - doi: 10.4025/actascibiolsci.v33i1.7313 Mass balance of nutrients during the filling phase of two reservoirs of Sistema Produtor Alto Tietê (SPAT - doi: 10.4025/actascibiolsci.v33i1.7313

    Directory of Open Access Journals (Sweden)

    Adalberto José Monteiro Junior

    2011-02-01

    Full Text Available Paraitinga and Biritiba reservoirs are part of Sistema Produtor Alto Tietê and they play an important role at the public water supply. The purpose of this study is to understand the mass balance of nitrogen and phosphorus that can influence the eutrophication process in reservoirs during the filling phase, and provide information for the implementation of mechanisms to manage water quality. Water samples were collected from August 2005 until May 2006. Concentrations of total phosphorus (PT and total nitrogen (NT were measured and the mass balance and loads were estimated. Paraitinga reservoir presented retention of NT and PT during the dry season and export during the rainy season; whilst at Biritiba reservoir we evidenced retention of NT and PT for both dry and rainy seasons. The annual balance demonstrated that during the reservoirs filling process, the systems retain NT and PT. The retention of nutrients into the system indicates that the environments have been modified leading to eutrophication and its consequences, and that it is necessary to outline strategies in order to mitigate the problem and suggest implementation of techniques to reduce the diffuse load.Paraitinga and Biritiba reservoirs are part of Sistema Produtor Alto Tiet�� and they play an important role at the public water supply. The purpose of this study is to understand the mass balance of nitrogen and phosphorus that can influence the eutrophication process in reservoirs during the filling phase, and provide information for the implementation of mechanisms to manage water quality. Water samples were collected from August 2005 until May 2006. Concentrations of total phosphorus (PT and total nitrogen (NT were measured and the mass balance and loads were estimated. Paraitinga reservoir presented retention of NT and PT during the dry season and export during the rainy season; whilst at Biritiba reservoir we evidenced retention of NT and PT for both dry and rainy seasons

  10. 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...

  11. Perceptions and attitudes among milk producers in Minas Gerais regarding cattle tick biology and control Percepções e atitudes entre produtores de leite em Minas Gerais relacionado a biologia e controle de carrapatos em bovinos

    Directory of Open Access Journals (Sweden)

    Maria Alice Zacarias do Amaral

    2011-09-01

    Full Text Available This study evaluates milk producers' knowledge regarding cattle ticks and practices for controlling them. Ninety-three dairymen in Minas Gerais were interviewed. These producers had no information regarding acaricide efficiency tests. To analyze the information, open responses were categorized through "content analysis", and descriptive analysis consisting of extracting the profile highlighted by the highest frequencies. The association between schooling level and knowledge was tested by means of chi-square trend tests. It was observed that 92.3% had no knowledge of the non-parasitic period. For 96.4%, what determined the time to apply treatment was the degree of tick infestation; 93.3% used spray guns to apply the acaricide. In seeking to cross-correlate the biological and control variables with education, cooperative action, length of experience and herd size, it was found that there was a linear association between schooling level and implementation of acaricide solution preparation. The other factors didn't show any significant association. These data demonstrated the need to instruct the producers in relation to the biology and control of Rhipicephalus (Boophilus microplus. It was concluded that the majority of milk producers were unaware of cattle tick biology and the factors that influence choosing an acaricide, which makes it difficult to implement strategic control.Este estudo teve como objetivo avaliar o conhecimento dos produtores de leite sobre o carrapato dos bovinos e seu controle. Foram entrevistados 93 produtores de leite de Minas Gerais. Estes produtores não tinham informação sobre testes de eficiência de carrapaticidas e controle de carrapatos. Foi testada associação entre a escolaridade e as práticas e conhecimento sobre os carrapatos e constatou-se que 92,3% dos produtores nada sabiam sobre o período não-parasitário. Para 96,4%, o que determinava o momento do tratamento era o grau de infestação de carrapatos; e 93

  12. Cloning and Characterization of the Aspergillus ochraceoroseus Aflatoxin Biosynthetic Gene Cluster

    Science.gov (United States)

    Production of the carcinogenic mycotoxin aflatoxin B1 has been reported from members of Aspergillus section Flavi, Aspergillus section Nidulantes, and a newly proposed section, Aspergillus section Ochraceorosei that consists of Aspergillus ochraceoroseus and the closely related A. rambellii. A. och...

  13. Dispositivos disciplinares produtores de subjetividade na instituição total Disciplinary agencies that are subjectivity producers in the total institution

    Directory of Open Access Journals (Sweden)

    Sílvio José Benelli

    2003-12-01

    Full Text Available Neste artigo, estamos desenvolvendo um estudo relativo às instituições totais. Pesquisamos no romance “O Ateneu” de Raul Pompéia quais são os dispositivos disciplinares produtores de subjetividade no contexto institucional. Trata-se de uma análise institucional tomando como campo de pesquisa um caso da literatura, pautada pelos referenciais de Goffman e de Foucault. Goffman diz o que são e como funcionam e indica o que produzem as instituições totais. Foucault, por sua vez, nos revela como são possíveis as instituições disciplinares e quais as razões de sua emergência. A leitura de Goffman a partir das análises de Foucault pode nos proporcionar um enriquecimento fecundo na compreensão dos processos de produção de subjetividade na sociedade contemporânea e, de modo específico, no contexto das instituições totais. Goffman analisa as práticas não-discursivas, ele as articula com grande sutileza, fazendo falar os “detalhes” mais pitorescos e aparentemente insignificantes do cotidiano institucional: percebemos então o plano microfísico das relações intra-institucionais, mergulhando nas diferentes estratégias nas quais o poder se ramifica, circula, domina e produz saberes e sujeitos.A study about total institution was developed. We have searched into the novel “O Ateneu”, by Raul Pompéia, which are the subjectivity disciplinary producer agencies in the institution milieu. It is an institutional analysis taking as a research field a case of literature, ruled by Goffman´s and Foucault´s works. Goffman demonstrated which the agencies are, how they work and indicated the production of total institutions. Foucault provided a source of understanding of the subjectivity production process into the contemporary society, and, specifically, into the total institution milieu. Goffman analyzed the non-discursive practices, articulating them subtly, and revealing that the bizarre and apparently insignificant

  14. Métodos exatos baseados em relaxações lagrangiana e surrogate para o problema de carregamento de paletes do produtor

    Directory of Open Access Journals (Sweden)

    Lilian Kátia de Oliveira

    2006-08-01

    Full Text Available Neste artigo apresentamos métodos exatos, baseados em relaxações Lagrangiana e surrogate, com bom desempenho para resolver o problema de carregamento de paletes do produtor. Este problema consiste em arranjar ortogonalmente e sem sobreposição o máximo número de retângulos de dimensões (l,w ou (l,w sobre um retângulo maior (L,W. Os métodos propostos são procedimentos de busca em árvore do tipo branch and bound que, em cada nó, utilizam limitantes derivados de relaxações Lagrangiana e/ou surrogate de uma formulação de programação linear 0-1. Algoritmos de otimização do subgradiente são usados para otimizar estes limitantes. São aplicados ainda testes de redução do problema e heurísticas Lagrangiana e surrogate para se obter boas soluções factíveis na otimização do subgradiente. Testes computacionais foram realizados utilizando exemplos da literatura e exemplos reais de uma transportadora. Os resultados mostram que um dos métodos propostos é competitivo com outros métodos da literatura, incluindo o software GAMS/CPLEX.In this paper we present exact methods, based on Lagrangean and surrogate relaxations, with good performance to solve the manufacturer's pallet loading problem. This problem consists of orthogonally arranging the maximum number of rectangles of sizes (l,w or (l,w into a larger rectangle (L,W without overlapping. The proposed methods involve a branch and bound based tree search procedure for which the bounds, in each node of the tree, are derived from Lagrangean and/or surrogate relaxations of a 0-1 linear programming formulation. Subgradient optimization algorithms are used to optimize such bounds. Problem reduction tests and Lagrangean and surrogate heuristics are also applied to obtain good feasible solutions in the subgradient optimization. Computational experiments were performed with instances of the literature and actual instances of a carrier. The results show that one of the proposed methods

  15. RELAÇÃO CONTRATUAL DOS PEQUENOS PRODUTORES RURAIS DA COMUNIDADE “CEDRAL” MUNICÍPIO DE ROSÁRIO OESTE - MT: COORDENAÇÃO VERTICAL E A INFORMALIDADE DOS CONTRATOS NA PRODUÇÃO DE MANDIOCA

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    Hélde Araújo Domingos

    2014-08-01

    Full Text Available O avanço dos estudos da Nova Economia Institucional (NEI se deu com incorporação de novos aportes teóricos principalmente a partir das três últimas décadas. Entre suas principais contribuições encontra-se à análise da interação entre agentes econômicos, em que se destaca o papel da economia dos custos de transações (ECT assumindo sua importância para o mercado. Portanto, o presente estudo tem como objetivo analisar os fatores que influenciam os produtores de mandioca da comunidade “Cedral” no município de Rosário Oeste a engajar-se em relação contratual formal ou informal e sua importância na relação comportamental desses produtores diante de tomada de decisão em adotar uma relação direta com o mercado ou decidir-se por uma integração vertical. Esta pesquisa utilizou-se de revisão bibliográfica buscando-se extrair as principais características e diferenças na fundamentação teórica e como ferramenta utilizou-se o modelo empírico (tobit, que analisa a ocorrência de variável dependente com distribuição truncada na regressão. Os resultados obtidos demonstraram a escolha por parte dos produtores em adotar a integração vertical, além da identificação de uma propensão à realização de contratos condicionada a especificidades dos ativos envolvidos no processo produtivo.

  16. O processo sucessório em propriedades de produtores de leite nos municípios de Coronel Xavier Chaves e Silveirânia, em Minas Gerais

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    Júlio César Mendes de Souza

    2013-10-01

    Full Text Available O objetivo deste estudo foi identificar os fatores que influenciam a presença de sucessores, em unidades familiares de produção de leite nos Municípios de Coronel Xavier Chaves e Silveirânia, em Minas Gerais. Utilizou-se, como referencial teórico, a influência dos valores tradicionais, e daqueles relacionados com a modernidade, no processo sucessório. Tomou-se, como hipótese, o fato de que o nível tecnológico, o tamanho da propriedade, o acesso ao crédito, a proximidade com o centro urbano e a escolaridade poderiam influenciar a presença do sucessor nas unidades produtoras de leite. Em termos de procedimentos metodológicos, trabalhou-se, nesta pesquisa, com a perspectiva comparativa entre produtores de leite de dois municípios mineiros que apresentavam níveis tecnológicos diferentes, entre si. Utilizou-se o método de levantamento com coleta de dados em campo, por meio da aplicação de 83 questionários semiestruturados a uma amostra de produtores de leite de caráter familiar. Para análise dos dados, utilizaram-se os testes t, qui-quadrado e de regressão. Os resultados não confirmaram a hipótese de que o nível de tecnologia seria fator interveniente no processo sucessório entre produtores de leite, porém se confirmaram as outras quatro hipóteses.

  17. Aspergillus bertholletius sp. nov. from Brazil Nuts

    DEFF Research Database (Denmark)

    Taniwaki, Marta H.; Pitt, John I.; Iamanaka, Beatriz T.;

    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 beta-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...

  18. Production of amylases by Aspergillus tamarii

    OpenAIRE

    Moreira Fabiana Guillen; Lima Francieli Arrias de; Pedrinho Sophia Renata Fazzano; Lenartovicz Veridiana; Souza Cristina Giatti Marques de; Peralta Rosane Marina

    1999-01-01

    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 glucoamy...

  19. Aspergillus endophthalmitis in orthotopic liver transplantation

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    Hosseini Hamid

    2009-06-01

    Full Text Available In this report, we describe a patient with drug-induced liver failure who developed endogenous endophthalmitis after liver transplantation. Our patient′s clinical course was so fulminant that the eye was lost in less than 1 month, without any response to therapy. Recognition of this infection is important because many patients die of disseminated Aspergillus infection, which may be detected early with bedside funduscopic examination by an ophthalmologist. Probably if the patient had referred to us earlier, it may have been possible to save the eye.

  20. Uma heurística simples e eficaz para resolver o problema do carregamento de paletes do produtor A simple and effective heuristic to solve the manufacturing pallet loading problem

    OpenAIRE

    Silvia Regina Morales; Reinaldo Morabito

    1997-01-01

    Neste artigo apresentamos uma heurística simples e eficaz para resolver o problema do carregamento de paletes (PCP) com caixas de mesma dimensão, também chamado PCP do produtor. Basicamente, o problema consiste em como arranjar, sem sobreposição, o maior número de retângulos (l,w) dentro de um retângulo maior (L,W). Este problema também aparece no carregamento de paletes sobre carrocerias de caminhões e no projeto de embalagens para formar unidades de carga intermediárias. Aparentemente simpl...

  1. Aflatoxins and ochratoxin A in stored barley grain in Spain and impact of PCR-based strategies to assess the occurrence of aflatoxigenic and ochratoxigenic Aspergillus spp.

    Science.gov (United States)

    Mateo, Eva M; Gil-Serna, Jéssica; Patiño, Belén; Jiménez, Misericordia

    2011-09-15

    Contamination of barley by moulds and mycotoxins results in quality and nutritional losses and represents a significant hazard to the food chain. The presence of aflatoxin B1 (AFB1), B2 (AFB2), G1 (AFG1) and G2 (AFG2) and ochratoxin A (OTA) in stored barley in Spain has been studied. Species-specific PCR assays were used for detection of Aspergillus flavus, A. parasiticus, A. ochraceus, A. steynii, A. westerdijkiae, A. carbonarius and A. niger aggregate in mycotoxin-positive barley samples at different incubation times (0, 1 and 2 days). Classical enumeration techniques (CFU/g) in different culture media for evaluation of Aspergillus in sections Flavi, Circumdati and Nigri were also used. One hundred and five barley kernel samples were collected in Spanish grain stores from 2008 to 2010, and analyzed using a previously optimized method involving accelerated solvent extraction, cleanup by immunoaffinity column, liquid chromatographic separation, post-column derivatization with iodine and fluorescence detection. Twenty-nine samples were contaminated with at least one of the studied mycotoxins. AFB1, AFB2, AFG1, AFG2, and OTA were detected in 12.4%, 2.9%, 4.8%, 2.9%, and 20% of the samples, respectively. Aflatoxins and OTA co-occurred in 4.8% of the samples. Maximum mycotoxin levels (ng/g) were 0.61 (AFB1), 0.06 (AFB2), 0.26 (AFG1), 0.05 (AFG2), and 2.0 (OTA). The results of PCR assays indicated the presence of all the studied species, except A. westerdijkiae. The PCR assays showed high levels of natural contamination of barley with the studied species of Aspergillus which do not correspond to the expected number of CFU/g in the cultures. These results suggest that a high number of non-viable spores or hyphae may exist in the samples. This is the first study carried out on the levels of aflatoxins and OTA in barley grain in Spain. Likewise, this is the first report on the presence of aflatoxigenic and ochratoxigenic Aspergillus spp. in barley grain naturally

  2. Effect of cinnamomum zeylanicum blume essential oil on the rowth and morphogenesis of some potentially pathogenic Aspergillus species Efeito do óleo essencial de Cinnamomum zeylanicum Blume sobre o crescimento e morfogênese de algumas espécies de Aspergillus potencialmente patogênicas

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    Egberto Santos Carmo

    2008-03-01

    Full Text Available Cinnamomum zeylanicum Blume is known for a wide range of medicinal properties. This study aimed to assess the interference of C. zeylanicum essential oil on the growth and morphogenesis of some potentially pathogenic Aspergillus species. The essential oil presented strong antifungal effect causing the growth inhibition of the assayed strains and development of large growth inhibition zones. MIC50 and MIC90 values were 40 and 80 µL/mL, respectively. 80, 40 and 20 µL/mL of the oil strongly inhibited the radial mycelial growth of A. niger, A. flavus and A. fumigatus along 14 days. 80 and 40 µL/mL of the oil caused a 100% inhibition of the fungal spore germination. Main morphological changes observed under light microscopy provided by the essential oil in the fungal strains were decreased conidiation, leakage of cytoplasm, loss of pigmentation and disrupted cell structure indicating fungal wall degeneration. It is concluded that C. zeylanicum essential oil could be known as potential antifungal compound, particularly, to protect against the growth of Aspergillus species.Cinnamomum zeylanicum Blume é uma planta conhecida por apresentar ampla variedade de propriedades medicinais. Portanto, este estudo teve por objetivo avaliar a interferência do óleo essencial C. zeylanicum sobre o crescimento e morfogênese de algumas espécies de Aspergillus potencialmente patogênicas. O óleo essencial testado apresentou potente efeito antifúngico demonstrado pela visualização de grandes zonas de inibição de crescimento de todas as linhagens testadas. Os valores de CIM50 e de CIM90 foram 40 e 80 µL/mL, respectivamente. Nas concentrações de 80, 40 e 20 µL/mL o óleo demonstrou um potente efeito fumigante, inibindo o crescimento micelial radial de A. niger, A. flavus e A. fumigatus ao longo de 14 dias de exposição. A 80 e 40 µL/mL o óleo essencial promoveu inibição de 100% da germinação de esporos, das três espécies de Aspergillus citadas

  3. Aspergillus pneumonia in renal transplant recipients

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-dong; HU Xiao-peng; YIN Hang; WANG Wei; ZHANG Xin; MA Lin-lin; WANG Yong

    2008-01-01

    Background Filamentous fungal infections are associated with a high morbidity and mortality in solid organ transplants.The present study aimed to investigate the aspergillus pneumonia in renal transplant recipients, and its diagnosis as well as treatment.Methods Approximately 2000 cases of renal transplants were retrospectively studied and we focused on cases hospitalized during August 1, 2005 and February 1, 2007, as the study period. The clinical database and electronic records were analyzed. Recently published literature was reviewed.Results There was more diabetes and hypertension in the infected group than in the non-infected group (86% vs 62% and 57% vs 39%, respectively). Eighty-six percent of recipients from the infected group had delayed graft function. Seven cases with aspergillus pneumonia were identified based on either fungal culture or radiology. Of the 7 cases, 4 died in a few days after diagnosis. Liposomal amphotericin B was used as a first-line therapy.Conclusions Incidences of fungal infection are increasing among renal transplant recipients. Early diagnosis and treatment are critical steps in curing aspergillosis.

  4. Aspergillus in the lung: diverse and coincident forms

    International Nuclear Information System (INIS)

    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.)

  5. Pulmonary hypersensitivity to Alternaria and Aspergillus in baker's asthma.

    Science.gov (United States)

    Klaustermeyer, W B; Bardana, E J; Hale, F C

    1977-05-01

    In two cases of baker's asthma pulmonary hypersensitivity was found to the fungi Alternaria and Aspergillus. Provocative bronchial challenge revealed a dual response; an immediate and an Arthus type hypersensitivity to Aspergillus in the first case. A primary binding assay revealed high titres of anti-Aspergillus antibody in the serum. In the second case intradermal and bronchial challenge suggested an immediate type I hypersensitivity response to Alternaria. The suspected organisms were present in the room air of the bakeries. It is suggested that an immunological response to these airborne fungi may have contributed to the pathogenesis of baker's asthma. PMID:561668

  6. Aspergillus pragensis sp nov discovered during molecular reidentification of clinical isolates belonging to Aspergillus section Candidi

    DEFF Research Database (Denmark)

    Lyskova, Pavlina; Hubka, Vit; Kolarik, Miroslav;

    2014-01-01

    The identity of nine clinical isolates recovered from Czech patients and presumptively identified as Aspergillus sp. section Candidi based on colony morphology was revised using sequences of beta-tubulin, calmodulin gene sequence, and internal transcribed spacer rDNA. Six isolates were from...... secondary metabolite analysis was also provided with comparison of metabolite spectrum to other species. Section Candidi now encompasses five species for which a dichotomous key based on colony characteristics is provided. All clinical isolates were tested for susceptibilities to selected antifungal agents...... suspected and proven onychomycosis, one from otitis externa, and two associated with probable invasive aspergillosis. The results showed that one Aspergillus candidus isolate was the cause of otitis externa, and both isolates obtained from sputa of patients with probable invasive aspergillosis were...

  7. Epidemiology of extended spectrum β-lactamase producing Enterobacter bacteremia in a brazilian hospital Epidemiologia de bacteremia causadas por Enterobacter produtores de β-lactamases de espectro estendido em um hospital brasileiro

    Directory of Open Access Journals (Sweden)

    Felipe Francisco Tuon

    2010-08-01

    Full Text Available INTRODUCTION: Enterobacter can be included in the group of extended spectrum β-lactamases (EBSL-producing bacteria, though few studies exist evaluating risk factors associated with this microorganism. A retrospective cohort study was conducted to determine risk factors associated with ESBL-producing-Enterobacter and mortality METHODS: A retrospective cohort study with 58 bacteremia caused by ESBL-producing-Enterobacter (28 cases and non-ESBL (30 cases RESULTS: Risk factors associated with ESBL-Enterobacter were trauma, length of hospitalization, admission to the intensive care unit, urinary catheter and elective surgery (pINTRODUÇÃO: Enterobacter pode ser incluído no grupo de bactérias produtoras de β-lactamases de espectro estendido (ESBL, mas existem poucos estudos avaliando fatores de risco para ESBL. Nós realizamos uma coorte retrospective para determiner fatores de risco associados com Enterobacter produtores de ESBL MÉTODOS: Uma coorte retrospectiva com 58 bacteremias por Enterobacter ESBL (28 casos e não-ESBL (30 casos RESULTADOS: Fatores de risco para ESBL-Enterobacter foram trauma, tempo de internação, admissão em UTI, sonda vesical e cirurgia eletiva (p<0.05. A mortalidade foi similar entre ESBL e não-ESBL CONCLUSÕES: Enterobacter produtor de ESBL é prevalente e a curva de mortalidade foi semelhante com o grupo não-ESBL.

  8. An Outbreak of Aspergillus Species in Response to Environmental Conditions in Serbia

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    Jelena Lević

    2013-01-01

    Full Text Available The frequency and incidence of A. flavus and A. niger on barley, maize, soybean, sunflowerand wheat grain, the abundance of European corn borer (Ostrinia nubilalis mothsand their interaction depending on weather conditions in the 2008-2012 period were studied.Under the agroecological conditions of Serbia, the species A. niger is more frequentthan A. flavus, and concerning the crop species, its frequency is highest in kernels of sunflower,than soybean, maize, barley and wheat. A. flavus was extremely dominant on allplant species in 2012 regarding its frequency: 100% on soybean, 95.3% on maize, 65.2% onbarley, 57.1% on sunflower and 45.8% on wheat. Furthermore, the incidence of A. flavus washigher in 2012 than in previous years. The uncommonly high frequency and incidence of A.flavus infestation of maize grain in 2012 were caused by extremely stressful agrometeorologicalconditions, high temperatures and drought over the period from flowering to waxymaturity of maize. The precipitation factor (Pf = precipitation sum / average monthly temperatureshowed that 2012 was extremely arid in June (Pf = 0.57, July (Pf = 1.45, August (Pf= 0.15 and September (Pf = 1.42. European corn borer (ECB was a second factor causingintensive occurrence of A. flavus on maize grain in 2012. The maximum flight of ECB mothswas recorded as early as in July (5,149 and, as a result of this, high damage and numerousinjuries were detected at harvest. Those injuries were covered by visible olive-green powderycolonies typical of A. flavus. In the chronology of A. flavus occurrence, these are thefirst data on its very high frequency and incidence under the agroecological conditions ofSerbia. As intensive infections with A. flavus were rare in the past 50 years, the level of aflatoxinsin maize grain was low.

  9. A novel fungal fruiting structure formed by Aspergillus niger and Aspergillus carbonarius in grape berries.

    Science.gov (United States)

    Pisani, Cristina; Nguyen, Trang Thoaivan; Gubler, Walter Douglas

    2015-09-01

    Sour rot, is a pre-harvest disease that affects many grape varieties. Sour rot symptoms include initial berry cracking and breakdown of berry tissue. This is a disease complex with many filamentous fungi and bacteria involved, but is usually initiated by Aspergillus niger or Aspergillus carbonarius. Usually, by the time one sees the rot there are many other organisms involved and it is difficult to attribute the disease to one species. In this study two species of Aspergillus were shown to produce a previously unknown fruiting structure in infected berries. The nodulous morphology, bearing conidia, suggests them to be an 'everted polymorphic stroma'. This structure forms freely inside the berry pulp and assumes multiple shapes and sizes, sometimes sclerotium-like in form. It is composed of a mass of vegetative hyphae with or without tissue of the host containing spores or fruiting bodies bearing spores. Artificially inoculated berries placed in soil in winter showed the possible overwintering function of the fruiting body. Inoculated berry clusters on standing vines produced fruiting structures within 21 d post inoculation when wounds were made at veraison or after (July-September). Histological studies confirmed that the fruiting structure was indeed fungal tissue. PMID:26321727

  10. 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

  11. Nonfunctionality of Aspergillus sojae aflR in a Strain of Aspergillus parasiticus with a Disrupted aflR Gene

    OpenAIRE

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

    2002-01-01

    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 ΔaflR 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 or...

  12. Desempenho dos arranjos institucionais e minimização dos custos de transação: transações entre produtores e fecularias de mandioca

    Directory of Open Access Journals (Sweden)

    Olivier Vilpoux

    2011-06-01

    Full Text Available No Brasil, a falta de competitividade do setor de fécula de mandioca em relação ao amido de milho é explicada pelas dificuldades em obter matéria-prima - raízes de mandioca - em quantidades e preços estáveis. A resolução desses problemas envolve a adoção de arranjos institucionais que estabilizam as transações entre produtores e industriais. A análise de 37 fecularias permitiu avaliar as características das transações e o desempenho dos arranjos adotados, medido por meio da capacidade das empresas em estabilizar seu fornecimento de matéria-prima. Os arranjos institucionais encontrados foram classificados em seis tipos, do mercado até a integração vertical, em função do nível de garantia oferecido para entrega de matéria-prima. Apesar da existência de especificidade dos ativos e de incerteza, as empresas preferem as transações via mercado spot, arranjo identificado como menos eficiente. A incerteza ligada ao funcionamento das instituições aumenta os custos de transação dos arranjos contratuais, o que explica a preferência dos atores pelo mercado. Os acordos contratuais com garantias intermediárias e fortes foram mais eficientes, mas com maiores custos de transação. Os resultados indicam dois caminhos para melhorar a competitividade do setor: (1 melhoria na eficiência do mercado, sistema com menores custos de transação; (2 redução dos custos de transação dos arranjos institucionais com maiores garantias, o que proporcionaria sistemas mais eficientes. Enquanto nenhuma dessas soluções for adotada, as fecularias brasileiras continuarão com arranjos de baixos custos de transação, mas fraco desempenho.The lack of competitiveness of Brazilian cassava starch industry in relation to corn starch is explained by the difficulty to obtain raw material (cassava roots in stable quantities and stable prices. The resolution of these problems involves the adoption of governance systems that stabilize the

  13. Mass balance of nutrients during the filling phase of two reservoirs of Sistema Produtor Alto Tietê (SPAT = Balanço de massa de nutrientes na fase de enchimento de dois reservatórios do Sistema Produtor Alto Tietê (SPAT

    Directory of Open Access Journals (Sweden)

    Valéria Cope

    2011-01-01

    Full Text Available Paraitinga and Biritiba reservoirs are part of Sistema Produtor Alto Tietê and they play an important role at the public water supply. The purpose of this study is to understand the mass balance of nitrogen and phosphorus that can influence the eutrophication process in reservoirs during the filling phase, and provide information for the implementation of mechanisms to manage water quality. Water samples were collected from August 2005 until May 2006. Concentrations of total phosphorus (PT and total nitrogen (NT were measured and the mass balance and loads were estimated. Paraitinga reservoir presented retention of NT and PT during the dry season and export during therainy season; whilst at Biritiba reservoir we evidenced retention of NT and PT for both dry and rainy seasons. The annual balance demonstrated that during the reservoirs filling process, the systems retain NT and PT. The retention of nutrients into the system indicatesthat the environments have been modified leading to eutrophication and its consequences, and that it is necessary to outline strategies in order to mitigate the problem and suggest implementation of techniques to reduce the diffuse load.Os reservatórios Paraitinga e Biritiba estão inseridos no Sistema Produtor Alto Tietê, com elevada importância para o abastecimento público. O objetivo do trabalho foi compreender o balanço de massa donitrogênio e fósforo os quais podem influenciar o processo de eutrofização em reservatórios durante o enchimento e subsidiar informações para implantação de mecanismos de gerenciamento da qualidade de água. Coletas trimestrais de água foram realizadas no período de um ano de agosto/2005 a maio/2006. As concentrações de fósforo total (PT e nitrogênio total (NT foram medidas, e estimadas as cargas e o balanço de massa. O reservatório Paraitinga indicou retenção de NT e PT no período seco, e exportação no chuvoso, e retenção de NT e PT para o período seco e

  14. Aspergillus antigen testing in bone marrow transplant recipients

    OpenAIRE

    Williamson, E; Oliver, D.; Johnson, E.; Foot, A.; D. Marks; Warnock, D.

    2000-01-01

    Aims—To assess the clinical usefulness of a commercial aspergillus antigen enzyme linked immunosorbent assay (ELISA) in the diagnosis of invasive aspergillosis (IA) in bone marrow transplant recipients, and to compare it with a commercial latex agglutination (LA) test.

  15. Polyphasic taxonomy of Aspergillus fumigatus and related species

    DEFF Research Database (Denmark)

    Hong, S.B.; Go, S.J.; Shin, H.D.;

    2005-01-01

    The variability within Aspergillus fumigalus Fresenius and related species was examined using macro-, micro-morphology, growth temperature regimes and extrolite patterns. In addition, DNA analyses including partial beta-tubulin, calmodulin and actin gene sequences were used. Detailed examination ...

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

    DEFF Research Database (Denmark)

    Perrone, Giancarlo; Stea, Gaetano; Epifani, Filomena;

    2011-01-01

    . 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......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...... 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...

  17. Genetics of Polyketide Metabolism in Aspergillus nidulans

    DEFF Research Database (Denmark)

    Klejnstrup, Marie L.; Frandsen, Rasmus John Normand; Holm, Dorte Koefoed;

    2012-01-01

    including polyketides. The majority of genes required for production of these metabolites are mostly organized in gene clusters, which often are silent or barely expressed under laboratory conditions, making discovery and analysis difficult. Fortunately, the genome sequences of several filamentous fungi are...... publicly available, greatly facilitating the establishment of links between genes and metabolites. This review covers the attempts being made to trigger the activation of polyketide metabolism in the fungal model organism Aspergillus nidulans. Moreover, it will provide an overview of the pathways where ten...... polyketide synthase genes have been coupled to polyketide products. Therefore, the proposed biosynthesis of the following metabolites will be presented; naphthopyrone, sterigmatocystin, aspyridones, emericellamides, asperthecin, asperfuranone, monodictyphenone/emodin, orsellinic acid, and the austinols....

  18. Microbial transformation of curcumol by Aspergillus niger.

    Science.gov (United States)

    Chen, Li-Xia; Zhang, Hui; Zhao, Qian; Yin, Shi-Yu; Zhang, Zhong; Li, Tian-Xian; Qiu, Feng

    2013-02-01

    Curcumol is a representative index component for the quality control of the essential oil of Curcuma wenyujin Y.H. Chen et C. Ling, an antivirus and anticancer drug in China. Microbial transformation of curcumol (1) by Aspergillus niger AS 3.739 yielded two products. Their structures were elucidated as 3alpha-hydroxycurcumol (2) and 3alpha-(4'-methoxy-succinyloxy)-curcumol (3) by extensive spectroscopic methods including 2D-NMR and HRESI-MS. Among them, 3 is a new compound. Esterification of the substrate with succinic acid is a novel reaction in the field of microbial transformation of natural products. Compound 2, the major transformation product of 1, was a high regio- and stereo-specific hydroxylation product and showed significant antiviral effects. PMID:23513713

  19. Aspergillus: a primer for the novice.

    Science.gov (United States)

    Bennett, J W

    2009-01-01

    Aspergillus is a genus of molds named after the morphological structure that bears asexual spores, the aspergillum, which resembles a liturgical device. This genus contains several species of positive or negative economic importance in industry, agriculture and medicine. The majority of aspergilli, including most species of economic importance, are known to reproduce only by asexual spores. Genome projects have been completed for A. fumigatus, A. nidulans, A. niger and A. oryzae; several other species are also being sequenced. The data from these genome projects have been useful in elucidating aspects of phylogeny, the evolution of sexuality and the extent of secondary metabolite diversity. To date, however, the impact on drug discovery, diagnosis of aspergillosis, and our understanding of fungal pathogenesis has been less pronounced. PMID:19253144

  20. Synthesis of lead nanoparticles by Aspergillus species.

    Science.gov (United States)

    Pavani, K V; Kumar, N Sunil; Sangameswaran, B B

    2012-01-01

    In the context of the current demand to develop green technologies in material synthesis, a natural process in the synthesis of lead particles by Aspergillus species to suit such technology is reported. The fungal strain was grown in medium containing different concentrations of lead (0.2-1.5 mM) to determine its resistance to heavy metals. The organism was found to utilize some mechanism and accumulate lead particles outside and inside the cell. The extracellular presence of lead particles in the range of 1.77-5.8 microm was characterized by scanning electron microscopy. The presence of particles of lead in the 5-20 nm size range was found on the cell surface, in the periplasmic space and in the cytoplasm and was analyzed by transmission electron microscopy. PMID:22708348

  1. 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.

  2. New ochratoxin A producing species of Aspergillus section Circumdati

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian; Frank, J.M.; Houbraken, J.A.M.P.; Kuijpers, A.F.A.; Samson, R.A.

    Aspergillus section Circumdati contains species with yellow to ochre conidia and non-black sclerotia that produce at least one of the following extrolites: ochratoxins, penicillic acids, xanthomegnins or melleins. The exception to this is A. robustus, which produces black sclerotia, phototropic...... A: Aspergillus cretensis, A. flocculosus, A. pseudoelegans, A. roseoglobulosus, A. westerdijkiae, A. sulphurous, and Neopetromyces muricatus. Two species produce large or small amounts of ochratoxin A, but less consistently: A. ochraceus and A. sclerotiorum. Ochratoxin production in these species...

  3. Significance and occurrence of fumonisins from Aspergillus niger

    OpenAIRE

    Mogensen, Jesper Mølgaard; Nielsen, Kristian Fog; Larsen, Thomas Ostenfeld; Frisvad, Jens Christian

    2012-01-01

    Fumonisins is a well-studied group of mycotoxins, mainly produced in maize by Fusarium species. However with the recent discovery of a fumonisin production by Aspergillus niger, other food commodities are at risk, since A. niger is a ubiquitous contaminant of many food and feed products. The objective of this thesis was to determine the significance and occurrence of fumonisins from Aspergillus niger in food, the frequency of fumonisin production in A. niger isolates, as well as studies of th...

  4. Aspergillus Mycoviruses Are Targets and Suppressors of RNA Silencing▿ †

    OpenAIRE

    Hammond, T. M.; Andrewski, M. D.; Roossinck, M J; Keller, N P

    2007-01-01

    RNA silencing can function as a virus defense mechanism in a diverse range of eukaryotes, and many viruses are capable of suppressing the silencing machinery targeting them. However, the extent to which this occurs between fungal RNA silencing and mycoviruses is unclear. Here, three Aspergillus dsRNA mycoviruses were partially characterized, and their relationship to RNA silencing was investigated. Aspergillus virus 1816 is related to Agaricus bisporus white button mushroom virus 1 and suppre...

  5. Aspergillus fumigatus Conidial Melanin Modulates Host Cytokine Response

    OpenAIRE

    Chai, Louis; Netea, Mihai; SUGUI, JANYCE; Vonk, Alieke; van de Sande, Wendy; Warris, Adilia; Kwon-Chung, Kyung; Jan Kullberg, Bart

    2009-01-01

    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 cytokine response. The albino conidia induced significantly more proinflammatory cytokines in human peripheral blood mononuclear cells (PBMC), as compared to melanised wild-type conidia. Blocking ...

  6. Immobilization of Isolated Lipase From Moldy Copra (Aspergillus Oryzae)

    OpenAIRE

    Seniwati

    2012-01-01

    Enzyme immobilization is a recovery technique that has been studied in several years, using support as a media to help enzyme dissolutions to the reaction substrate. Immobilization method used in this study was adsorption method, using specific lipase from Aspergillus oryzae. Lipase was partially purified from the culture supernatant of Aspergillus oryzae. Enzyme was immobilized by adsorbed on silica gel. Studies on free and immobilized lipase systems for determination of op...

  7. Immobilization of Isolated Lipase From Moldy Copra (Aspergillus Oryzae)

    OpenAIRE

    Seniwati Dali; A. B. D. Rauf Patong; M.Noor Jalaluddin; Pirman; Baharuddin Hamzah

    2011-01-01

    Enzyme immobilization is a recovery technique that has been studied in several years, using support as a media to help enzyme dissolutions to the reaction substrate. Immobilization method used in this study was adsorption method, using specific lipase from Aspergillus oryzae. Lipase was partially purified from the culture supernatant of Aspergillus oryzae. Enzyme was immobilized by adsorbed on silica gel. Studies on free and immobilized lipase systems for determination of optimum pH, optimum ...

  8. Accessory enzymes from Aspergillus involved in xylan and pectin degradation

    OpenAIRE

    Vries, de, G.

    1999-01-01

    The xylanolytic and pectinolytic enzyme systems from Aspergillus have been the subject of study for many years. Although the main chain cleaving enzymes and their encoding genes have been studied in detail, little information is available about most of the accessory enzymes and their corresponding genes. This thesis describes the purification and characterisation of two accessory enzymes from Aspergillus , feruloyl esterase A (FaeA) andα-glucuronidase A (AguA), and the activities of these enz...

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

    International Nuclear Information System (INIS)

    Three fungal strains, Aspergillus awamorii A9, Aspergillus awamorii A23 and Aspergillus oryzae O2, 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 A9, 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

  10. Biosynthetic Pathway of the Reduced Polyketide Product Citreoviridin in Aspergillus terreus var. aureus Revealed by Heterologous Expression in Aspergillus nidulans.

    Science.gov (United States)

    Lin, Tzu-Shyang; Chiang, Yi-Ming; Wang, Clay C C

    2016-03-18

    Citreoviridin (1) belongs to a class of F1-ATPase β-subunit inhibitors that are synthesized by highly reducing polyketide synthases. These potent mycotoxins share an α-pyrone polyene structure, and they include aurovertin, verrucosidin, and asteltoxin. The identification of the citreoviridin biosynthetic gene cluster in Aspergillus terreus var. aureus and its reconstitution using heterologous expression in Aspergillus nidulans are reported. Two intermediates were isolated that allowed the proposal of the biosynthetic pathway of citreoviridin. PMID:26954888

  11. The Aspergillus Genome Database, a curated comparative genomics resource for gene, protein and sequence information for the Aspergillus research community

    OpenAIRE

    Arnaud, Martha B.; Chibucos, Marcus C; Costanzo, Maria C.; Crabtree, Jonathan; Inglis, Diane O.; Lotia, Adil; Orvis, Joshua; Shah, Prachi; Skrzypek, Marek S.; Binkley, Gail; Miyasato, Stuart R.; Wortman, Jennifer R.; Sherlock, Gavin

    2009-01-01

    The Aspergillus Genome Database (AspGD) is an online genomics resource for researchers studying the genetics and molecular biology of the Aspergilli. AspGD combines high-quality manual curation of the experimental scientific literature examining the genetics and molecular biology of Aspergilli, cutting-edge comparative genomics approaches to iteratively refine and improve structural gene annotations across multiple Aspergillus species, and web-based research tools for accessing and exploring ...

  12. 含有额外拷贝黄曲霉cyp51同源基因的烟曲霉对抗真菌药物的敏感性测定%Antifungal susceptibility of the A.fumigatus transformants containing extra copies of A.flavus cyp51 gene homologues to the common antifungal drugs

    Institute of Scientific and Technical Information of China (English)

    刘伟霞; 孙毅; 万喆; 李若瑜; 刘伟

    2011-01-01

    Objective To investigate the effect of Aspergillus flavus cyp51 genes on antifungal susceptibility by cloning and constucting the extra copies of Aspergillus flavus cyp51 genes. Methods A.flavus cyp5l gene homologues were identified by tblastn searches inA. flavus genome database. PCR fragments composed of the 5'flanking sequence (approximately 1 000 bp) ofcyp51 ,cyp51 ORF, and its 3'flanking sequence (approximately 1 000 bp), were subcloned into shuttle plasmid pRG3-AMAl-NotI to produce recombinant plasmids. These plasmids and empty plasmid pRG3-AMA1-Notl were transformed into A.fumigatus strain AF293.1 (pyrG-) respectively to produce transformants. The Clinical Laboratory Standard Institute broth microdilution method M38-A2 and E-test method were used to assay the minimal inhibitory concentrations (MICs) of itraconazole ( ITC), voriconazole ( VRC), amphotericin B (AMB), and posaconazole (POS), or minimal effect concentration (MEC) of caspofungin (CAS), against these transformants. Results A. flavus genome contains three cyp51 gene homologues, cyp51A ,cyp51B and cyp51 C, of which the ORF size are 1 400-2 000 bp. When these genes were subcloned into shuttle plasmid pRG3-AMA1-NotI, we get plasmids pRG3-AMA1-CYP51 A, pRG3-AMA1-CYP51B and pRG3-AMA1-CYP51C. These plasmids and empty plasmid were transformed into A.fumigatus strain AF293.1 (pyrG-) to produce transformants rCYP51A, rCYP51B, rCYP51C and rpRG. The antifungal susceptibility of these A.fumigatus transformants to the antifungal drugs by broth microdilution assaying and E-test method showed that, rCYP51A and rCYP51B were cross-resistant to VRC and ITC, susceptible to both AM B and CAS; rCYP51C and rpRG were intermediate to ITC and VRC, susceptible to both A MB and CAS. Conclusion In A. fumigatus , extra copies of A.flavus ' cyp51A gene or cyp51B gene have effect on antifungal susceptibility to azoles, have no effect on AMB and CAS. Extra copy ofcyp51C has no obvious effect on all the tested drugs.%目的

  13. Enantioselective degradation and unidirectional chiral inversion of 2-phenylbutyric acid, an intermediate from linear alkylbenzene, by Xanthobacter flavus PA1

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yishan; Han, Ping [School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong (China); Li, Xiao-yan; Shih, Kaimin [Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (China); Gu, Ji-Dong, E-mail: jdgu@hkucc.hku.hk [School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong (China); The Swire Institute of Marine Science, The University of Hong Kong, Shek O, Cape d' Aguilar, Hong Kong (China)

    2011-09-15

    Highlights: {yields} We isolated a Xanthobacter flavus strain PA1 utilizing the racemic 2-PBA and the single enantiomers as the sole source of carbon and energy. {yields} Both (R) and (S) forms of enantiomers can be degraded in a sequential manner in which the (S) disappeared before the (R) form. {yields} The biochemical degradation pathway involves an initial oxidation of the alkyl side chain before aromatic ring cleavage. - Abstract: Microbial degradation of the chiral 2-phenylbutyric acid (2-PBA), a metabolite of surfactant linear alkylbenzene sulfonates (LAS), was investigated using both racemic and enantiomer-pure compounds together with quantitative stereoselective analyses. A pure culture of bacteria, identified as Xanthobacter flavus strain PA1 isolated from the mangrove sediment of Hong Kong Mai Po Nature Reserve, was able to utilize the racemic 2-PBA as well as the single enantiomers as the sole source of carbon and energy. In the presence of the racemic compounds, X. flavus PA1 degraded both (R) and (S) forms of enantiomers to completion in a sequential manner in which the (S) enantiomer disappeared much faster than the (R) enantiomer. When the single pure enantiomer was supplied as the sole substrate, a unidirectional chiral inversion involving (S) enantiomer to (R) enantiomer was evident. No major difference was observed in the degradation intermediates with either of the individual enantiomers when used as the growth substrate. Two major degradation intermediates were detected and identified as 3-hydroxy-2-phenylbutanoic acid and 4-methyl-3-phenyloxetan-2-one, using a combination of liquid chromatography-mass spectrometry (LC-MS), and {sup 1}H and {sup 13}C nuclear magnetic resonance (NMR) spectroscopy. The biochemical degradation pathway follows an initial oxidation of the alkyl side chain before aromatic ring cleavage. This study reveals new evidence for enantiomeric inversion catalyzed by pure culture of environmental bacteria and emphasizes the

  14. Neopetromyces gen. nov and an overview of teleomorphs of Aspergillus subgenus Circumdati

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian; Samson, R. A.

    2000-01-01

    Species in the anamorph genus Aspergillus are associated with several teleomorphic genera in the Eurotiales and the most important mycotoxin producers are concentrated in Aspergillus subgenus Circumdati. A new genus, Neopetromyces, is proposed for the recently described Petromyces muricatus, beca...

  15. The potential impact of the pulmonary microbiome on immunopathogenesis of Aspergillus-related lung disease

    NARCIS (Netherlands)

    Kolwijck, E.; Veerdonk, F.L. van de

    2014-01-01

    Aspergillosis is an infection or allergic response caused by fungi of the genus Aspergillus. The most common forms of aspergillosis are allergic bronchopulmonary aspergillosis, chronic pulmonary aspergillosis, and invasive pulmonary aspergillosis. Aspergillus also plays an important role in fungal s

  16. A PRODUÇÃO E INDUSTRIALIZAÇÃO DO CAFÉ DOS PRINCIPAIS PRODUTORES BRASILEIROS E A ECONOMIA NACIONAL: SIMULAÇÕES SOB UM MODELO INTER-REGIONAL DE INSUMO-PRODUTO

    OpenAIRE

    Sakon, Fernando M.; Guilhoto, Joaquim José Martins; Bliska, Flavia M. M.; Imori, Denise; Camargo, Fernanda S.

    2008-01-01

    Este trabalho tem como objetivo analisar o comportamento e a importância atual dos setores de produção agrícola e de industrialização de café de cada um dos principais Estados produtores brasileiros (Minas Gerais, Espírito Santo, São Paulo, Paraná, Bahia e Rondônia) em relação às respectivas economias estaduais e em relação aos demais setores da economia nacional. Para tanto, foi construído um sistema inter-regional de insumo-produto, para o ano de 2002, com sete regiões e 44 setores por regi...

  17. Isolation and partial characterization of a mutant of Bacillus thuringiensis producing melanin Isolamento e caracterização parcial de um mutante de Bacillus thuringiensis produtor de melanina

    Directory of Open Access Journals (Sweden)

    Gislayne T. Vilas-Bôas

    2005-09-01

    Full Text Available A mutant (407-P of Bacillus thuringiensis subsp. thuringiensis strain 407 producing a melanin was obtained after treatment with the mutagenic agent ethyl-methane-sulfonate. Several microbiological and biochemical properties of the two strains were analyzed and the results were similar. The mutant 407-P was also incorporated into non-sterilized soil samples, recovered, easily identified, and quantified, what enables its use in ecology of B. thuringiensis.Um mutante (407-P da linhagem Bacillus thuringiensis subsp. thuringiensis 407 produtor de melanina foi obtido após tratamento com o agente mutagênico etil-metano-sulfonato. Diversas propriedades microbiológicas e bioquímicas das duas linhagens foram analisadas e os resultados foram similares. O mutante 407-P foi incorporado em amostras de solo não esterilizado, recuperado, facilmente identificado e quantificado, possibilitando seu uso em estudos de ecologia de B. thuringiensis.

  18. Inhibition of conidiophore development in Aspergillus fumigatus by an Escherichia coli DH5α strain, a promising antifungal candidate against aspergillosis.

    Science.gov (United States)

    Balhara, M; Ruhil, S; Kumar, M; Dhankhar, S; Chhillar, A K

    2014-03-01

    The opportunistic human pathogen Aspergillus fumigatus produces a massive number of asexual spores (conidia) as the primary means of dispersal, survival, genome protection and infection of hosts. In this report, we investigated secretory and cytosolic proteins of non-pathogenic bacterial species (mostly belonging to human microbiome) for antifungal potential against A. fumigatus, A. flavus and A. niger. Our preliminary results revealed that cytosolic proteins of E. coli DH5α were most active and the less toxic against various pathogenic isolates of A. fumigatus (the major pathogenic species), depicting a minimum inhibitory concentration (MIC) of 62.50 μg/mL, 62.50 μg/mL and 12.50 μg/disc using microbroth dilution assay (MDA), percentage spore germination inhibition assay (PSGI) and disc diffusion assay (DDA), respectively. E. coli protein was non-toxic against human erythrocytes at doses up to 1000 μg/mL as compared to standard drug, amphotericin B which lysed 100% of erythrocytes at a concentration of 37.50 μg/mL. Time kill analysis proved it to be fungicidal in a concentration and time-dependent manner. Scanning electron microscopic studies (SEM) were carried out to prevail what kind of damage it causes to A. fumigatus. SEM results reported that conidiophore (structures forming conidia) development was halted as a major consequence, reducing the number of conidiophores to insignificant values as well as alteration in their morphological attributes. This feature may contribute to the development of new prevention strategies against Aspergillus infections. Hyphal atrophy was also observed, evidenced by shrinking and flattening of hyphal walls and reduced, abrupt hyphal branching. Such actions may effectively reduce the invasive ability of Aspergillus as well as it can sterilize the fungal burden by obstructing the conidiation pathway of A. fumigatus. Hence, E. coli DH5α, being a commensal species, can lead to the development of antifungal molecule with novel

  19. Abastecendo plantations: A inserção do charque fabricado em Pelotas (RS no comércio atlântico das carnes e a sua concorrência com os produtores platinos (século XIX

    Directory of Open Access Journals (Sweden)

    Jonas Moreira VARGAS

    2014-12-01

    Full Text Available O charque (carne-seca constituiu alimento fundamental na dieta dos escravos das plantations açucareiras e cafeeiras e das populações pobres das cidades litorâneas do Brasil. O artigo analisa a inserção do charque fabricado em Pelotas (Rio Grande do Sul no mercado atlântico, assim como a concorrência com os produtores uruguaios e argentinos e como as guerras travadas na região da fronteira sul afetaram o comércio da mercadoria. Durante a segunda metade do século XIX, a carne-seca rio-grandense foi perdendo espaço no comércio atlântico para o produto platino, mais saboroso e de preço mais acessível. Na busca de novos mercados consumidores para além do Brasil e de Cuba, tanto os rio-grandenses quanto os produtores do Rio da Prata não conseguiram penetrar no mercado britânico, em que o paladar era mais exigente e se associava o charque à comida de escravos. Com o tempo, os argentinos conseguiram modernizar sua indústria com remessa de carne congelada para a Europa, ao passo que os rio-grandenses sucumbiram diante dessa nova concorrência e das exigências dos consumidores, não resistindo à derradeira crise que afetou o setor na década de 1880.

  20. Uma heurística simples e eficaz para resolver o problema do carregamento de paletes do produtor A simple and effective heuristic to solve the manufacturing pallet loading problem

    Directory of Open Access Journals (Sweden)

    Silvia Regina Morales

    1997-04-01

    Full Text Available Neste artigo apresentamos uma heurística simples e eficaz para resolver o problema do carregamento de paletes (PCP com caixas de mesma dimensão, também chamado PCP do produtor. Basicamente, o problema consiste em como arranjar, sem sobreposição, o maior número de retângulos (l,w dentro de um retângulo maior (L,W. Este problema também aparece no carregamento de paletes sobre carrocerias de caminhões e no projeto de embalagens para formar unidades de carga intermediárias. Aparentemente simples de ser resolvido otimamente, o PCP do produtor em geral é difícil do ponto de vista da teoria de complexidade, e diversos autores têm proposto métodos de solução aproximados. No presente artigo apresentamos um refinamento da heurística de Bischoff e Dowsland, de fácil implementação computacional e que foi capaz de obter a solução ótima de todos os exemplos aqui analisados.In this paper we present a simple and effective heuristic to solve the pallet loading problem (PLP with identical boxes, namely the manufacturer's PLP. Basically, the problem consists of arranging the maximum number of rectangles (l,w into a larger rectangle (L,W without overlapping. This problem also arises in the loading of pallets into trucks or rail cars, and in the design of packages which will be further combined to form a unit load. Although apparently easy to be optimally solved, the manufacturer's PLP is difficult from the perspective of the complexity theory, and several authors have proposed approximate methods to treat it. In this paper we present a refinement of Bischoff and Dowsland's heuristic which is easily implementable in a computer and provided the optimal solution of all examples here analysed.

  1. Sexual structures in Aspergillus: morphology, importance and genomics.

    Science.gov (United States)

    Geiser, David M

    2009-01-01

    The genus Aspergillus comprises a few hundred species sharing a common asexual spore forming structure, the aspergillum. Approximately one-third of these species also produce a sexual stage, all but five of which are known to be homothallic. Sexual stages associated with Aspergillus fall into approximately ten different genera, reflecting a tremendous degree of phylogenetic and biological diversity. Sexual stages in Aspergillus are plectomycetous, typical for the order in which it resides, the Eurotiales. Theoretically, a homothallic Aspergillus species can produce both asexual conidia and sexual ascospores in both clonal and recombinant fashion, although the actual significance of these potential modes of reproduction is unclear. Aspergillus species with known sexual stages tend to be minor players in infections of humans, perhaps because of their tendency to produce fewer asexual spores compared to their non-teleomorphic congeners. The discovery of population genetic and genomic evidence for sex in species with no known sexual stage indicates that no assumptions can be made about the clonal versus recombinant life histories of a species based on its known mitotic and/or meiotic reproductive modes. PMID:18608901

  2. Overexpression of protein disulfide isomerase in Aspergillus.

    Science.gov (United States)

    El-Adawi, H; Khanh, N Q; Gassen, H

    2000-10-01

    One of the major problems with the production of biotechnologically valuable proteins has been the purification of the product. For Escherichia coli and Saccharomyces cerevisiae, there are several techniques for the purification of intracellular proteins, but these are time consuming and often result in poor yields. Purification can be considerably facilitated, if the product is secreted from the host cell. In the work presented, we have constructed an expression vector (pSGNH2) for the secretion of protein disulfide isomerase (PDI; EC 5.3.4.1) from Aspergillus niger, in which the retention signal His-Asp-Glu-Leu (H-D-E-L) was modified to Ala-Leu-Glu-Gln (A-L-E-Q) via the polymerase chain reaction (PCR) method. The PDI gene was placed under the control of the A. oryzae alpha-amylase promoter. This expression vector was transformed into A. niger NRRL3, resulting in PDI secretion into the medium. The catalytic activity of overexpressed PDI from A. niger was indistinguishable from that of PDI isolated from bovine liver. With further strain improvement and optimization of culture conditions, it could be possible to raise the PDI production to the bioprocessing scale. PMID:10977899

  3. Genetics of Polyketide Metabolism in Aspergillus nidulans

    Directory of Open Access Journals (Sweden)

    Marie L. Klejnstrup

    2012-01-01

    Full Text Available Secondary metabolites are small molecules that show large structural diversity and a broad range of bioactivities. Some metabolites are attractive as drugs or pigments while others act as harmful mycotoxins. Filamentous fungi have the capacity to produce a wide array of secondary metabolites including polyketides. The majority of genes required for production of these metabolites are mostly organized in gene clusters, which often are silent or barely expressed under laboratory conditions, making discovery and analysis difficult. Fortunately, the genome sequences of several filamentous fungi are publicly available, greatly facilitating the establishment of links between genes and metabolites. This review covers the attempts being made to trigger the activation of polyketide metabolism in the fungal model organism Aspergillus nidulans. Moreover, it will provide an overview of the pathways where ten polyketide synthase genes have been coupled to polyketide products. Therefore, the proposed biosynthesis of the following metabolites will be presented; naphthopyrone, sterigmatocystin, aspyridones, emericellamides, asperthecin, asperfuranone, monodictyphenone/emodin, orsellinic acid, and the austinols.

  4. Fingernail Onychomycosis Due to Aspergillus niger.

    Science.gov (United States)

    Kim, Dong Min; Suh, Moo Kyu; Ha, Gyoung Yim; Sohng, Seung Hyun

    2012-11-01

    Onychomycosis is usually caused by dermatophytes, but some species of nondermatophytic molds and yeasts are also associated with nail invasion. Aspergillus niger is a nondermatophytic mold which exists as an opportunistic filamentous fungus in all environments. Here, we report a case of onychomycosis caused by A. niger in a 66-year-old female. The patient presented with a black discoloration and a milky white base and onycholysis on the proximal portion of the right thumb nail. Direct microscopic examination of scrapings after potassium hydroxide (KOH) preparation revealed dichotomous septate hyphae. Repeated cultures on Sabouraud's dextrose agar (SDA) without cycloheximide produced the same black velvety colonies. No colony growth occurred on SDA with cycloheximide slants. Biseriate phialides covering the entire vesicle with radiate conidial heads were observed on the slide culture. The DNA sequence of the internal transcribed spacer region of the clinical sample was a 100% match to that of A. niger strain ATCC 16888 (GenBank accession number AY373852). A. niger was confirmed by KOH mount, colony identification, light microscopic morphology, and DNA sequence analysis. The patient was treated orally with 250 mg terbinafine daily and topical amorolfine 5% nail lacquer for 3 months. As a result, the patient was completely cured clinically and mycologically. PMID:23197914

  5. Apical control of conidiation in Aspergillus nidulans.

    Science.gov (United States)

    Oiartzabal-Arano, Elixabet; Perez-de-Nanclares-Arregi, Elixabet; Espeso, Eduardo A; Etxebeste, Oier

    2016-05-01

    The infection cycle of filamentous fungi consists of two main stages: invasion (growth) and dispersion (development). After the deposition of a spore on a host, germination, polar extension and branching of vegetative cells called hyphae allow a fast and efficient invasion. Under suboptimal conditions, genetic reprogramming of hyphae results in the generation of asexual spores, allowing dissemination to new hosts and the beginning of a new infection cycle. In the model filamentous fungus Aspergillus nidulans, asexual development or conidiation is induced by the upstream developmental activation (UDA) pathway. UDA proteins transduce signals from the tip, the polarity site of hyphae, to nuclei, where developmental programs are transcriptionally activated. The present review summarizes the current knowledge on this tip-to-nucleus communication mechanism, emphasizing its dependence on hyphal polarity. Future approaches to the topic will also be suggested, as stimulating elements contributing to the understanding of how apical signals are coupled with the transcriptional control of development and pathogenesis in filamentous fungi. PMID:26782172

  6. Ultrasonographic findings of aspergillus bursitis in a patient with a renal transplantation: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Byeong Seong; Yang, Myeon Jun; Kim, Young Min; Youm, Yoon Seok; Choi, Seong Hoon; Park, Sung Bin; Jeong, Ae Kyung [University of Ulsan College of Medicine, Ulsan University Hospital, Ulsan (Korea, Republic of)

    2008-04-15

    Aspergillus bursitis is an uncommon condition demonstrated as a nonspecific soft tissue mass. To our knowledge, the ultrasonographic findings of aspergillus bursitis in immunocompromised patients have not been previously reported. Here, we report a case of aspergillus bursitis in a renal transplant recipient, accompanied by the associated ultrasonographic findings.

  7. Ultrasonographic findings of aspergillus bursitis in a patient with a renal transplantation: a case report

    International Nuclear Information System (INIS)

    Aspergillus bursitis is an uncommon condition demonstrated as a nonspecific soft tissue mass. To our knowledge, the ultrasonographic findings of aspergillus bursitis in immunocompromised patients have not been previously reported. Here, we report a case of aspergillus bursitis in a renal transplant recipient, accompanied by the associated ultrasonographic findings

  8. Involvement of the opportunistic pathogen Aspergillus tubingensis in osteomyelitis of the maxillary bone: a case report

    Directory of Open Access Journals (Sweden)

    Bathoorn Erik

    2013-02-01

    Full Text Available Abstract Background Aspergillus tubingensis is a black Aspergillus belonging to the Aspergillus section Nigri, which includes species that morphologically resemble Aspergillus niger. Recent developments in species determination have resulted in clinical isolates presumed to be Aspergillus niger being reclassified as Aspergillus tubingensis by sequencing. We present a report of a patient with an osteomyelitis of the maxillary bone with a probable invasive Aspergillus tubingensis infection. Case presentation We describe an immune compromised patient suffering from osteomyelitis of the maxillary bone after tooth extraction. The osteomyelitis probably resulted in dentogenic pansinusitis presenting as an acute ethmoiditis. Histologic examination of biopsy samples showed osteomyelitis, and inflammation of the surrounding connective tissue. Cultures of the alveolar wound grew Aspergillus tubingensis. The patient was treated with liposomal amphoterocin B, which was changed to oral treatment with voriconazole based on susceptibility testing (MIC for voriconazole was 1 μg/ml. Conclusion This case shows that Aspergillus tubingensis may have the potential to cause severe invasive infections in immunocompromised hosts. A larger proportion of Aspergillus tubingensis isolates are less susceptible to azoles compared to Aspergillus niger. Therefore, correct species identification and susceptibility testing is crucial for the choice of anti-fungal treatment, screening of azole resistance, and characterization of the pathogenic potential of the various species within Aspergillus section Nigri.

  9. Use of glycerol coating to control aflatoxin production by Aspergillus parasiticus in peanut grains

    Directory of Open Access Journals (Sweden)

    Juliana F. Moreira Silva

    2015-10-01

    Full Text Available Peanut grains are very susceptible to aflatoxin contamination. Aflatoxins are toxic metabolites produced by Aspergillus flavus, A. nomius and A. parasiticus. The aflatoxin B1 is most frequently found in peanuts, posing a high toxicological risk due to its carcinogenic, teratogenic and mutagenic properties. Alternative methods to fungicides can be used to protect grains. GRAS (Generally Regarded As Safe substances can be an interesting option to avoid contamination, specially glycerol. In the present work, the ability of glycerol films to prevent aflatoxin production by A. parasiticus in peanuts was evaluated. Glycerol was established in two different ways: by immersion and aspersion. Aspersion was more efficient in reducing aflatoxin production (86.3% than was the immersion process (66.9% (P < 0.05. At the same time, a progressive reduction in A. parasiticus colony diameters was observed (from 38.6 ± 0.9 to 34.4 ± 1.7 mm when the fungus was grown on GYEP medium supplemented with glycerol (0 to 5%. However, varying concentrations did not influence the production of spores, colonies, conidiophores or spore condition. Peanuts coated with 5% glycerol (by immersion or aspersion had improved characteristics, with a cleaner and more shiny appearance, which can make the resulting product more acceptable to the population. In conclusion, the reduction of aflatoxin production in peanut grains with glycerol, particularly by aspersion, was satisfactory, and this GRAS substance shows promising potential to be used to prevent mycotoxin contamination in grains.Key words: GRAS substances. Mycotoxin. Grain storage. Food preservation. RESUMO O amendoim é muito suscetível à contaminação por aflatoxinas, que são metabólitos tóxicos produzidos por Aspergillus flavus, A. parasiticus e A. nomius. A aflatoxina B1 é a mais frequentemente encontrada nos amendoins e apresenta risco toxicológico devido às suas propriedades carcinogênicas, teratogênicas e

  10. Biochemical and Structural Characterization of Amy1: An Alpha-Amylase from Cryptococcus flavus Expressed in Saccharomyces cerevisiae

    Science.gov (United States)

    Galdino, Alexsandro Sobreira; Silva, Roberto Nascimento; Lottermann, Muriele Taborda; Álvares, Alice Cunha Morales; de Moraes, Lídia Maria Pepe; Torres, Fernando Araripe Gonçalves; de Freitas, Sonia Maria; Ulhoa, Cirano José

    2011-01-01

    An extracellular alpha-amylase (Amy1) whose gene from Cryptococcus flavus was previously expressed in Saccharomyces cerevisiae was purified to homogeneity (67 kDa) by ion-exchange and molecular exclusion chromatography. The enzyme was activated by NH4+ and inhibited by Cu+2 and Hg+2. Significant biochemical and structural discrepancies between wild-type and recombinant α-amylase with respect to Km values, enzyme specificity, and secondary structure content were found. Far-UV CD spectra analysis at pH 7.0 revealed the high thermal stability of both proteins and the difference in folding pattern of Amy1 compared with wild-type amylase from C. flavus, which reflected in decrease (10-fold) of enzymatic activity of recombinant protein. Despite the differences, the highest activity of Amy1 towards soluble starch, amylopectin, and amylase, in contrast with the lowest activity of Amy1w, points to this protein as being of paramount biotechnological importance with many applications ranging from food industry to the production of biofuels. PMID:21490699

  11. Binturong (Arctictis binturong and Kinkajou (Potos flavus digestive strategy: implications for interpreting frugivory in Carnivora and primates.

    Directory of Open Access Journals (Sweden)

    Joanna E Lambert

    Full Text Available Exclusive frugivory is rare. As a food resource, fruit is temporally and spatially patchy, low in protein, and variable in terms of energy yield from different carbohydrate types. Here, we evaluate the digestive physiology of two frugivorous Carnivora species (Potos flavus, Arctictis binturong that converge with primates in a diversity of ecological and anatomical traits related to fruit consumption. We conducted feeding trials to determine mean digestive retention times (MRT on captive animals at the Carnivore Preservation Trust (now Carolina Tiger Rescue, Pittsboro, NC. Fecal samples were collected on study subjects for in vitro analysis to determine methane, pH, and short chain fatty acid profiles; fiber was assayed using standard neutral detergent (NDF and acid detergent (ADF fiber methods. Results indicate that both carnivoran species have rapid digestive passage for mammals that consume a predominantly plant-based diet: A. binturong MRT = 6.5 hrs (0.3; P. flavus MRT = 2.5 hrs (1.6. In vitro experiments revealed no fermentation of structural polysaccharides--methane levels did not shift from 0 h to either 24 or 48 hours and no short chain fatty acids were detected. In both species, however, pH declined from one incubation period to another suggesting acidification and bacterial activity of microbes using soluble carbohydrates. A comparison with primates indicates that the study species are most similar in digestive retention times to Ateles--the most frugivorous anthropoid primate taxon.

  12. Recombinant bacterial hemoglobin alters metabolism of Aspergillus niger

    DEFF Research Database (Denmark)

    Hofmann, Gerald; Diano, Audrey; Nielsen, Jens

    2009-01-01

    The filamentous fungus Aspergillus niger is used extensively for the production of enzymes and organic acids. A major problem in industrial fermentations with this fungus is to ensure sufficient supply of oxygen required for respiratory metabolism of the fungus. In case of oxygen limitation, the ...... to attenuate unwanted side effects resulting from oxygen limitation during industrial fermentations with A. niger.......The filamentous fungus Aspergillus niger is used extensively for the production of enzymes and organic acids. A major problem in industrial fermentations with this fungus is to ensure sufficient supply of oxygen required for respiratory metabolism of the fungus. In case of oxygen limitation, the...... behind the strong gpdA promoter from Aspergillus nidulans. Analysis of secreted metabolites, oxygen uptake, CO2 evolution and biomass formation points towards a relief of stress in the mutant expressing VHB when it is exposed to oxygen limitation. Our findings therefore point to an interesting strategy...

  13. Electrochemical monitoring of citric acid production by Aspergillus niger

    International Nuclear Information System (INIS)

    Highlights: • Citric acid fermentation process (production) by Aspergillus niger. • Qualitative/quantitative monitoring of standard culture and culture infected with yeast. • Electronic tongue based on potentiometric and voltammetric sensors. • Evaluation of the progress and the correctness of the fermentation process. • The highest classification abilities of the hybrid electronic tongue. - Abstract: Hybrid electronic tongue was developed for the monitoring of citric acid production by Aspergillus niger. The system based on various potentiometric/voltammetric sensors and appropriate chemometric techniques provided correct qualitative and quantitative classification of the samples collected during standard Aspergillus niger culture and culture infected with yeast. The performance of the proposed approach was compared with the monitoring of the fermentation process carried out using classical methods. The results obtained proved, that the designed hybrid electronic tongue was able to evaluate the progress and correctness of the fermentation process

  14. Electrochemical monitoring of citric acid production by Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Kutyła-Olesiuk, Anna; Wawrzyniak, Urszula E.; Ciosek, Patrycja; Wróblewski, Wojciech, E-mail: wuwu@ch.pw.edu.pl

    2014-05-01

    Highlights: • Citric acid fermentation process (production) by Aspergillus niger. • Qualitative/quantitative monitoring of standard culture and culture infected with yeast. • Electronic tongue based on potentiometric and voltammetric sensors. • Evaluation of the progress and the correctness of the fermentation process. • The highest classification abilities of the hybrid electronic tongue. - Abstract: Hybrid electronic tongue was developed for the monitoring of citric acid production by Aspergillus niger. The system based on various potentiometric/voltammetric sensors and appropriate chemometric techniques provided correct qualitative and quantitative classification of the samples collected during standard Aspergillus niger culture and culture infected with yeast. The performance of the proposed approach was compared with the monitoring of the fermentation process carried out using classical methods. The results obtained proved, that the designed hybrid electronic tongue was able to evaluate the progress and correctness of the fermentation process.

  15. 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.

  16. 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.

  17. Heterologous expression of Aspergillus terreus fructosyltransferase in Kluyveromyces lactis.

    Science.gov (United States)

    Spohner, Sebastian C; Czermak, Peter

    2016-06-25

    Fructo-oligosaccharides are prebiotic and hypocaloric sweeteners that are usually extracted from chicory. They can also be produced from sucrose using fructosyltransferases, but the only commercial enzyme suitable for this purpose is Pectinex Ultra, which is produced with Aspergillus aculeatus. Here we used the yeast Kluyveromyces lactis to express a secreted recombinant fructosyltransferase from the inulin-producing fungus Aspergillus terreus. A synthetic codon-optimised version of the putative β-fructofuranosidase ATEG 04996 (XP 001214174.1) from A. terreus NIH2624 was secreted as a functional protein into the extracellular medium. At 60°C, the purified A. terreus enzyme generated the same pattern of oligosaccharides as Pectinex Ultra, but at lower temperatures it also produced oligomers with up to seven units. We achieved activities of up to 986.4U/mL in high-level expression experiments, which is better than previous reports of optimised Aspergillus spp. fermentations. PMID:27084521

  18. Aspergillus sellar abscess: Case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Hao Li

    2008-01-01

    Full Text Available Aspergillus sellar abscess is a very rare form of fungal infections of the central nervous system (CNS. In this report, we describe the successful treatment of a patient with aspergillus sellar abscess. A 65-year-old woman presented with headache, nasal discharge and decreased visual acuity. The diagnosis of sellar mass was made on the basis of magnetic resonance imaging (MRI examination. The computed tomography (CT scan revealed sellar enlargement and sellar floor bony destruction. After hospitalization the patient underwent transsphenoidal surgery. Histopathological examination of the sellar mass revealed aspergillosis. Postoperatively, amphotericine-B and itraconazole therapy was started. During a six-month follow-up, the patient′s headache and inertia disappeared, visual acuity improved. Aspergillus sellar abscess must be considered in the differential diagnosis of a sellar mass. The correct diagnosis of pituitary aspergillosis can only be achieved by histopathological examination. Surgical intervention and antifungal therapy should be considered the optimal treatment.

  19. Biosorption potency of Aspergillus niger for removal of chromium (VI).

    Science.gov (United States)

    Srivastava, Shaili; Thakur, Indu Shekhar

    2006-09-01

    Aspergillus niger isolated from soil and effluent of leather tanning mills had higher activity to remove chromium. The potency of Aspergillus niger was evaluated in shake flask culture by absorption of chromium at pH 6 and temperature 30 degrees C. The results of the study indicated removal of more than 75% chromium by Aspergillus niger determined by diphenylcarbazide colorimetric assay and atomic absorption spectrophotometry after 7 days. Study of microbial Cr(VI) reduction and identification of reduction intermediates has been hindered by the lack of analytical techniques that can identify the oxidation state with subcellular spatial resolution. Therefore, removal of chromium was further substantiated by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX), which indicated an accumulation of chromium in the fungal mycelium. PMID:16874547

  20. Acute community acquired Aspergillus pneumonia in a presumed immunocompetent host

    Science.gov (United States)

    Sridhar, Varun; Rajagopalan, Natarajan; C, Shivaprasad; Patil, Mahantesh; Varghese, Jaicob

    2012-01-01

    Infection from Aspergillus results in a wide range of diseases from simple Aspergillus pneumonia to fatal invasive Aspergillosis. Though the fungus is known to predominantly affect the immunocompromised host, it has also been known to cause acute pneumonia in immunocompetent hosts which is invariably fatal. It presents as an acute pneumonia with bilateral chest infiltrates on radiograph. Early clinical suspicion and microbiological identification by measures such as broncho alveolar lavage and initiation of therapy with voricanozole significantly increase the chances of survival. In this article the authors discuss a case of acute community acquired Aspergillus pneumonia in an immunocompetent host who survived due to early identification and prompt treatment with appropriate antifungal medication. PMID:22605848