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Sample records for aspergillus niger lactate

  1. Proteome analysis of Aspergillus niger: Lactate added in starch-containing medium can increase production of the mycotoxin fumonisin B2 by modifying acetyl-CoA metabolism

    Directory of Open Access Journals (Sweden)

    Andersen Mikael R

    2009-12-01

    Full Text Available Abstract Background Aspergillus niger is a filamentous fungus found in the environment, on foods and feeds and is used as host for production of organic acids, enzymes and proteins. The mycotoxin fumonisin B2 was recently found to be produced by A. niger and hence very little is known about production and regulation of this metabolite. Proteome analysis was used with the purpose to reveal how fumonisin B2 production by A. niger is influenced by starch and lactate in the medium. Results Fumonisin B2 production by A. niger was significantly increased when lactate and starch were combined in the medium. Production of a few other A. niger secondary metabolites was affected similarly by lactate and starch (fumonisin B4, orlandin, desmethylkotanin and pyranonigrin A, while production of others was not (ochratoxin A, ochratoxin alpha, malformin A, malformin C, kotanin, aurasperone B and tensidol B. The proteome of A. niger was clearly different during growth on media containing 3% starch, 3% starch + 3% lactate or 3% lactate. The identity of 59 spots was obtained, mainly those showing higher or lower expression levels on medium with starch and lactate. Many of them were enzymes in primary metabolism and other processes that affect the intracellular level of acetyl-CoA or NADPH. This included enzymes in the pentose phosphate pathway, pyruvate metabolism, the tricarboxylic acid cycle, ammonium assimilation, fatty acid biosynthesis and oxidative stress protection. Conclusions Lactate added in a medium containing nitrate and starch can increase fumonisin B2 production by A. niger as well as production of some other secondary metabolites. Changes in the balance of intracellular metabolites towards a higher level of carbon passing through acetyl-CoA and a high capacity to regenerate NADPH during growth on medium with starch and lactate were found to be the likely cause of this effect. The results lead to the hypothesis that fumonisin production by A. niger

  2. Proteome analysis of Aspergillus niger: Lactate added in starch-containing medium can increase production of the mycotoxin fumonisin B2 by modifying acetyl-CoA metabolism

    OpenAIRE

    Andersen Mikael R; Lametsch Rene; Sørensen Louise M; Nielsen Per V; Frisvad Jens C

    2009-01-01

    Background: Aspergillus niger is a filamentous fungus found in the environment, on foods andfeeds and is used as host for production of organic acids, enzymes and proteins. The mycotoxin fumonisin B2 was recently found to be produced by A. niger and hence very little is known about production and regulation of this metabolite. Proteome analysis was used with the purpose to reveal how fumonisin B2 production by A. niger is influenced by starch and lactate in the medium.Results: Fumonisin B2 pr...

  3. 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

  4. 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...

  5. 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....

  6. 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...

  7. Proteome analysis of Aspergillus niger: Lactate added in starch-containing medium can increase production of the mycotoxin fumonisin B2 by modifying acetyl-CoA metabolism

    DEFF Research Database (Denmark)

    Sørensen, Louise Marie; Lametsch, Rene; Andersen, Mikael Rørdam;

    2009-01-01

    other processes that affect the intracellular level of acetyl-CoA or NADPH. This included enzymes in the pentose phosphate pathway, pyruvate metabolism, the tricarboxylic acid cycle, ammonium assimilation, fatty acid biosynthesis and oxidative stress protection. Conclusions Lactate added in a medium...... regulation of this metabolite. Proteome analysis was used with the purpose to reveal how fumonisin B2 production by A. niger is influenced by starch and lactate in the medium. Results Fumonisin B2 production by A. niger was significantly increased when lactate and starch were combined in the medium....... Production of a few other A. niger secondary metabolites was affected similarly by lactate and starch (fumonisin B4, orlandin, desmethylkotanin and pyranonigrin A), while production of others was not (ochratoxin A, ochratoxin alpha, malformin A, malformin C, kotanin, aurasperone B and tensidol B). The...

  8. 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...

  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. 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...

  12. 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

  13. 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...

  14. 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

  15. Significance and occurrence of fumonisins from Aspergillus niger

    DEFF Research Database (Denmark)

    Mogensen, Jesper Mølgaard

    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 the effect of physiological factors affecting fumonisin production. Major findings in this context have....... Sixty-six A. niger strains were isolated and screened for a fumonisin production, and 77 % produced fumonisin on agar media. Worst-case scenarios were made by inoculation of A. niger on grapes and solidified the thought that a potential fumonisin production/contamination in grapes and derived products...

  16. Draft Genome Sequence of Aspergillus niger Strain An76

    OpenAIRE

    Gong, Weili; Cheng, Zhi; Zhang, Huaiqiang; Liu, Lin; Gao, Peiji; Wang, Lushan

    2016-01-01

    The filamentous fungus Aspergillus niger has become one of the most important fungi in industrial biotechnology, and it can efficiently secrete both polysaccharide-degrading enzymes and organic acids. We report here the 6,074,961,332-bp draft sequence of A. niger strain An76, and the findings provide important information related to its lignocellulose-degrading ability.

  17. 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...

  18. 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...

  19. 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

  20. 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.

  1. 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.

  2. 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

  3. Fumonisin and Ochratoxin Production in Industrial Aspergillus niger Strains

    DEFF Research Database (Denmark)

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

    2011-01-01

    Aspergillus niger is perhaps the most important fungus used in biotechnology, and is also one of the most commonly encountered fungi contaminating foods and feedstuffs, and occurring in soil and indoor environments. Many of its industrial applications have been given GRAS status (generally regarded...... as safe). However, A. niger has the potential to produce two groups of potentially carcinogenic mycotoxins: fumonisins and ochratoxins. In this study all available industrial and many non-industrial strains of A. niger (180 strains) as well as 228 strains from 17 related black Aspergillus species...... were examined for mycotoxin production. None of the related 17 species of black Aspergilli produced fumonisins. Fumonisins (B(2), B(4), and B(6)) were detected in 81% of A. niger, and ochratoxin A in 17%, while 10% of the strains produced both mycotoxins. Among the industrial strains the same ratios...

  4. Genetic relationships among strains of the Aspergillus niger aggregate

    DEFF Research Database (Denmark)

    Ferracin, L.M.; Frisvad, Jens Christian; Taniwaki, M.H.; Iamanaka, B.T.; Sartori, D.; Schaoavaloff, M.E.; Fungaro, M.H.P.

    2009-01-01

    We analyzed the genetic relationships between 51 fungal isolates previously identified as A. niger aggregate, obtained from dried fruit samples from worldwide origin and 7 A. tubingensis obtained from Brazilian coffee beans samples. Greater fungal diversity was found in black sultanas. Aspergillus...

  5. Metabolic control analysis of Aspergillus niger L-arabinose catabolism

    DEFF Research Database (Denmark)

    de Groot, M.J.L.; Prathumpai, Wai; Visser, J.; Ruijter, G.J.G.

    2005-01-01

    A mathematical model of the L-arabinose/D-xylose catabolic pathway of Aspergillus niger was constructed based on the kinetic properties of the enzymes. For this purpose L-arabinose reductase, L-arabitol dehydrogenase and D-xylose reductase were purified using dye-affinity chromatography, and their...

  6. Study on radiation sterilization of aspergillus niger pectinase

    International Nuclear Information System (INIS)

    The result of radiation sterilization of aspergillus niger pectinase liquid by 60Co γ-rays was reported. When absorbed dose was from 1 to 25 kGy, enzyme activity didn't reduce. When absorbed dose was 15 kGy. There are no active strains in the enzyme liquid; and enzyme activity of the enzyme liquid preserved had better preserved effect

  7. Enhanced citrate production through gene insertion in Aspergillus niger

    DEFF Research Database (Denmark)

    Jongh, Wian de; Nielsen, Jens

    2007-01-01

    The effect of inserting genes involved in the reductive branch of the tricarboxylic acid (TCA) cycle on citrate production by Aspergillus niger was evaluated. Several different genes were inserted individually and in combination, i.e. malate dehydrogenase (mdh2) from Saccharomyces cerevisiae, two...

  8. Production of Aspergillus niger beta-mannosidase in Pichia pastoris

    Czech Academy of Sciences Publication Activity Database

    Fliedrová, Barbora; Gerstorferová, Daniela; Křen, Vladimír; Weignerová, Lenka

    2012-01-01

    Roč. 85, č. 2 (2012), s. 159-164. ISSN 1046-5928 R&D Projects: GA ČR GAP207/10/0321; GA ČR GD305/09/H008; GA MŠk(CZ) 7E11011 Keywords : Beta-mannosidase * Aspergillus niger * Cloning Subject RIV: CE - Biochemistry Impact factor: 1.429, year: 2012

  9. Fumonisins in Aspergillus niger: Industrial and food aspects

    DEFF Research Database (Denmark)

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

    Introduction: Fumonisins are toxic seconday metabolites from Fusarium verticillioides and other Fusaria, from Tolypocladium and Aspergillus niger 1,2. Being a generalist Aspergillus niger is the workhorse in a very large number of industrial applications, and is also a common contaminant in foods...... ever used in biotechnology could produce fuminisins B2, B4 & B6. The strains could be subdivided into two clades (representing A. niger and the “phylospecies” A. awamori), and there were fumonisin producers in both clades. Ochratoxin A was also produced by strains in both clades, but only...... of approximately 6% of the strains. None of the other species in the black Aspergilli produced fumonisins. One strain (NRRL 337), called the “food fungus”, because it is used for single cell protein based on cheap growth substrates, produced both fumonisins and ochratoxin A. Industrial citric acid producers...

  10. Growth Inhibition of Aspergillus niger by Cinnamaldehyde and Eugenol

    OpenAIRE

    Narumol MATAN

    2007-01-01

    Inhibitory effects of cinnamaldehyde and eugenol against Aspergillus niger, major spoilage mold of fruits and nuts, were investigated. A. niger inoculated on agar plates was exposed to paper discs impregnated with 10 μL of cinnamaldehyde and eugenol at various concentrations (10 - 100 mg/ml) before incubating at 25 °C for 3 days. Antifungal activities of cinnamaldehyde and eugenol at the minimum inhibitory concentration (MIC) were examined at various temperatures ranging from 20 °C to 37 °C. ...

  11. Production of extremophilic bacterial cellulase enzymes in aspergillus niger.

    Energy Technology Data Exchange (ETDEWEB)

    Gladden, John Michael

    2013-09-01

    Enzymes can be used to catalyze a myriad of chemical reactions and are a cornerstone in the biotechnology industry. Enzymes have a wide range of uses, ranging from medicine with the production of pharmaceuticals to energy were they are applied to biofuel production. However, it is difficult to produce large quantities of enzymes, especially if they are non-native to the production host. Fortunately, filamentous fungi, such as Aspergillus niger, are broadly used in industry and show great potential for use a heterologous enzyme production hosts. Here, we present work outlining an effort to engineer A. niger to produce thermophilic bacterial cellulases relevant to lignocellulosic biofuel production.

  12. 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...

  13. Biosorption of Cadmium by Fungal Biomass of Aspergillus niger

    Institute of Scientific and Technical Information of China (English)

    QI YANG; JIAN-LONG WANG; ZHI XING

    2005-01-01

    Objective To investigate the removal of cadmium from aqueous solution by waste fungal biomass of Aspergillus niger, originated from citric acid fermentation industry. Methods Batch adsorption test was used to study the biosorption equilibrium and isotherm. The Cd2+ concentration was measured with atomic adsorption spectrophotometer (AAS) HITACHI 180-80. Results The biosorption achieved equilibrium within 30 min. The adsorption isotherm could be described by Freundlich adsorption model, and the constants KF and 1/n were determined to be 2.07 and 0.18, respectively, and the correlation efficiency was 0.97. The optimal pH for Cd adsorption was 6.0. The cadmium-laden biomass could be effectively regenerated using 0.1 N HCl. Conclusion The waste biomass of Aspergillus niger, a by-product of fermentation industry, is a potential biosorbent for the removal of cadmium from aqueous solution.

  14. Biosorption of cadmium using the fungus Aspergillus niger

    Directory of Open Access Journals (Sweden)

    L.M. Barros Júnior

    2003-09-01

    Full Text Available Sorption experiments using the Aspergillus niger fungus for cadmium removal were carried out to study the factors influencing and optimizing the biosorption of this metal. The effects of pH, time, biomass concentration, and initial concentration of the heavy metal on the rate of metallic biosorption were examined. An experimental design was also used to determine the values of the under study variables that provided the greatest biosorption efficiency. A technique for biomass recovery was also developed with the objective of determining the capacity of the regenerated biomass to biosorb the metals in solution. This research proved that with a pH of 4.75, a biomass concentration of 0.7 g/L, and a heavy metal concentration varying between 5 and 10 mg/L a biosorption process of biosorption with Aspergillus niger could be successfully used for heavy metal removal from oil field water in the oil industry.

  15. Biotransformation of steviol derivatives by Aspergillus niger and Fusarium moniliforme

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Bras H. de; Leal, Paulo C. [Parana Univ., Curitiba, PR (Brazil). Dept. de Quimica]. E-mail: bho@ufpr.br; Souza Filho, Jose Dias [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Quimica

    2005-04-01

    Steviol derivatives have been submitted to biotransformations by fungi. Methyl ent-11{beta},13-dihydroxy-15,16-epoxikauran-19-oate was hydroxylated at C-11 by Aspergillus niger, whereas ent-16{beta}-hydroxybeyeran-19-oic acid was hydroxylated at C-6 and C-7 by Fusarium moniliforme. The hydroxylation at non-activated positions at the carbon skeleton is discussed in connection with the properties of important polyhydroxylated diterpenoids described in the literature. (author)

  16. Biosorption of cadmium using the fungus Aspergillus niger

    OpenAIRE

    Barros Júnior L.M.; Macedo G.R.; Duarte M.M.L.; Silva E.P.; Lobato A.K.C.L.

    2003-01-01

    Sorption experiments using the Aspergillus niger fungus for cadmium removal were carried out to study the factors influencing and optimizing the biosorption of this metal. The effects of pH, time, biomass concentration, and initial concentration of the heavy metal on the rate of metallic biosorption were examined. An experimental design was also used to determine the values of the under study variables that provided the greatest biosorption efficiency. A technique for biomass recovery was als...

  17. Protein secretion in the filamentous fungus Aspergillus niger

    OpenAIRE

    Weenink, Xavier Oswin

    2008-01-01

    Filamentous fungi are multicellular eukaryotic organisms, which represent a separate taxonomic group organisms within the fungal kingdom, apart from the yeasts. These fungi always need a substrate to grow on, this can be living or dead material. Fungi possess the capacity to secrete high levels of enzymes. Because of this specific property, fungi are already used for centuries as miniature factories for the production of extracellular proteins. Aspergillus niger is an attractive organism beca...

  18. Biotransformation of steviol derivatives by Aspergillus niger and Fusarium moniliforme

    International Nuclear Information System (INIS)

    Steviol derivatives have been submitted to biotransformations by fungi. Methyl ent-11β,13-dihydroxy-15,16-epoxikauran-19-oate was hydroxylated at C-11 by Aspergillus niger, whereas ent-16β-hydroxybeyeran-19-oic acid was hydroxylated at C-6 and C-7 by Fusarium moniliforme. The hydroxylation at non-activated positions at the carbon skeleton is discussed in connection with the properties of important polyhydroxylated diterpenoids described in the literature. (author)

  19. Pectinases of Aspergillus niger: A Molecular and Biochemical Characterisation

    OpenAIRE

    Parenicová, L.

    2000-01-01

    The major topics of this thesis are the microfilamentous fungus Aspergillus niger and the pectinases a group of extracellular enzymes. Many 'products' of this species hold the GRAS (Generally Regarded As Safe) status and thus pectinases find a broad range of applications in food, feed and beverage industries.Pectinases are enzymes which degrade pectin, a heteropolysaccharide found in the middle lamella and the primary cell wall of higher plants. The number of pectinase-encoding genes identifi...

  20. Transcriptome analysis of Aspergillus niger grown on sugarcane bagasse

    Directory of Open Access Journals (Sweden)

    Goldman Gustavo H

    2011-10-01

    Full Text Available Abstract Background Considering that the costs of cellulases and hemicellulases contribute substantially to the price of bioethanol, new studies aimed at understanding and improving cellulase efficiency and productivity are of paramount importance. Aspergillus niger has been shown to produce a wide spectrum of polysaccharide hydrolytic enzymes. To understand how to improve enzymatic cocktails that can hydrolyze pretreated sugarcane bagasse, we used a genomics approach to investigate which genes and pathways are transcriptionally modulated during growth of A. niger on steam-exploded sugarcane bagasse (SEB. Results Herein we report the main cellulase- and hemicellulase-encoding genes with increased expression during growth on SEB. We also sought to determine whether the mRNA accumulation of several SEB-induced genes encoding putative transporters is induced by xylose and dependent on glucose. We identified 18 (58% of A. niger predicted cellulases and 21 (58% of A. niger predicted hemicellulases cellulase- and hemicellulase-encoding genes, respectively, that were highly expressed during growth on SEB. Conclusions Degradation of sugarcane bagasse requires production of many different enzymes which are regulated by the type and complexity of the available substrate. Our presently reported work opens new possibilities for understanding sugarcane biomass saccharification by A. niger hydrolases and for the construction of more efficient enzymatic cocktails for second-generation bioethanol.

  1. 21 CFR 173.120 - Carbohydrase and cellulase derived from Aspergillus niger.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Carbohydrase and cellulase derived from Aspergillus niger. 173.120 Section 173.120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...) Aspergillus niger is classified as follows: Class, Deuteromycetes; order, Moniliales; family,...

  2. Production of Fumonisin B-2 and B-4 by Aspergillus niger on Grapes and Raisins

    DEFF Research Database (Denmark)

    Mogensen, Jesper Mølgaard; Frisvad, Jens Christian; Thrane, Ulf;

    2010-01-01

    The recent discovery of fumonisin production in Aspergillus niger, raises concerns about the presence of these mycotoxins in grapes and raisins as well as other commodities where A. niger is a frequent contaminant. Here we investigate the potential production of fumonisins in A. niger cultured on...

  3. Biotransformations of organic compounds mediated by cultures of Aspergillus niger.

    Science.gov (United States)

    Parshikov, Igor A; Woodling, Kellie A; Sutherland, John B

    2015-09-01

    Many different organic compounds may be converted by microbial biotransformation to high-value products for the chemical and pharmaceutical industries. This review summarizes the use of strains of Aspergillus niger, a well-known filamentous fungus used in numerous biotechnological processes, for biochemical transformations of organic compounds. The substrates transformed include monocyclic, bicyclic, and polycyclic aromatic hydrocarbons; azaarenes, epoxides, chlorinated hydrocarbons, and other aliphatic and aromatic compounds. The types of reactions performed by A. niger, although not unique to this species, are extremely diverse. They include hydroxylation, oxidation of various functional groups, reduction of double bonds, demethylation, sulfation, epoxide hydrolysis, dechlorination, ring cleavage, and conjugation. Some of the products may be useful as new investigational drugs or chemical intermediates. PMID:26162670

  4. Uranium leaching using mixed organic acids produced by Aspergillus niger

    International Nuclear Information System (INIS)

    Both of culture temperature and pH value had impacts on the degree of uranium extraction through changing types and concentrations of mixed organic acids produced by Aspergillus niger, and significant interactions existed between them though pH value played a leading role. And with the change of pH value of mixed organic acids, the types and contents of mixed organic acids changed and impacted on the degree of uranium extraction, especially oxalic acid, citric acid and malic acid. The mean degree of uranium extraction rose to peak when the culture temperature was 25 deg C (76.14 %) and pH value of mixed organic acids was 2.3 (82.40 %) respectively. And the highest one was 83.09 %. The optimal culture temperature (25 deg C) of A. niger for uranium leaching was different from the most appropriate growing temperature (37 deg C). (author)

  5. UTILIZING Aspergillus niger FOR BIOREMEDIATION OF TANNERY EFFLUENT

    Directory of Open Access Journals (Sweden)

    Jyoti Bisht

    2014-03-01

    Full Text Available Tannery waste water is characterized by highly toxic ammonium, sulfates, surfactants, acids, dyes, sulfonated oils and organic substances, including natural or synthetic tannins. This study was designed to study the potential of Aspergillus niger for bioremediation of tannery effluent. Addition of glucose as a carbon source in the tannery effluent encouraged the growth of A. niger but there was no change in physico-chemical parameters. The toxic effects were mostly reduced after treatment when 20% mineral salt medium was added in tannery effluent. Colour, COD, TS, TDS, TSS, chlorides, sulfides and chromium reduction were 71.9%, 72.1%, 69.0%, 65.0%, 68.1%, 66.8%, 65.7% and 57.8%, respectively.

  6. Chitosan Obtained from Cell Wall of Aspergillus Niger Mycelium

    Institute of Scientific and Technical Information of China (English)

    HUANG Hui-li; LIN Wen-luan; LIN Jian-ming

    2004-01-01

    Chitin from cell walls of Aspergillus Niger mycelium was prepared. A new method for the preparation of high deacetylation degree chitosan was studied in a dilute sodium hydroxide solution at a high pressure. The experimental results indicate that the deacetylation degree of the chitosan can reach 80% under the condition of a 5.00 mol/L sodium hydroxide solution at 0.1 MPa of pressure for 1 h. This method shows the advantages of the applications in the industry production and environment protection.

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

    DEFF Research Database (Denmark)

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

  8. Putative Aspergillus niger-induced oxalate nephrosis in sheep.

    Science.gov (United States)

    Botha, C J; Truter, M; Bredell, T; Lange, L; Mülders, M S G

    2009-03-01

    A sheep farmer provided a maize-based brewer's grain (mieliemaroek) and bales of Eragrostis curvula hay to ewes and their lambs, kept on zero-grazing in pens. The 'mieliemaroek' was visibly mouldy. After 14 days in the feedlot, clinical signs, including generalised weakness, ataxia of the hind limbs, tremors and recumbency, were noticed. Six ewes died within a period of 7 days. A post mortem examination was performed on 1 ewe. The carcass appeared to be cachectic with mild effusions into the body cavities; mild lung congestion and pallor of the kidneys were observed. Microscopical evaluation revealed nephrosis and birefringent oxalate crystals in the renal tubules when viewed under polarised light. A provisional diagnosis of oxalate nephrosis with subsequent kidney failure was made. Amongst other fungi, Aspergillus niger was isolated from 'mieliemaroek' samples submitted for fungal culture and identification. As A. niger is known to synthesise oxalates, a qualitative screen to detect oxalic acid in the mieliemaroek and purified A. niger isolates was performed using high-performance liquid chromatography (HPLC). Oxalic acid was detected, which supported a diagnosis of soluble oxalate-induced nephropathy. PMID:19653520

  9. In-silico analysis of Aspergillus niger beta-glucosidases

    Science.gov (United States)

    Yeo S., L.; Shazilah, K.; Suhaila, S.; Abu Bakar F., D.; Murad A. M., A.

    2014-09-01

    Genomic data mining was carried out and revealed a total of seventeen β-glucosidases in filamentous fungi Aspergillus niger. Two of them belonged to glycoside hydrolase family 1 (GH1) while the rest belonged to genes in family 3 (GH3). These proteins were then named according to the nomenclature as proposed by the International Union of Biochemistry (IUB), starting from the lowest pI and glycoside hydrolase family. Their properties were predicted using various bionformatic tools showing the presence of domains for signal peptide and active sites. Interestingly, one particular domain, PA14 (protective antigen) was present in four of the enzymes, predicted to be involved in carbohydrate binding. A phylogenetic tree grouped the two glycoside hydrolase families with GH1 and GH3 related organisms. This study showed that the various domains present in these β-glucosidases are postulated to be crucial for the survival of this fungus, as supported by other analysis.

  10. Tandem shock waves to enhance genetic transformation of Aspergillus niger.

    Science.gov (United States)

    Loske, Achim M; Fernández, Francisco; Magaña-Ortíz, Denis; Coconi-Linares, Nancy; Ortíz-Vázquez, Elizabeth; Gómez-Lim, Miguel A

    2014-08-01

    Filamentous fungi are used in several industries and in academia to produce antibiotics, metabolites, proteins and pharmaceutical compounds. The development of valuable strains usually requires the insertion of recombinant deoxyribonucleic acid; however, the protocols to transfer DNA to fungal cells are highly inefficient. Recently, underwater shock waves were successfully used to genetically transform filamentous fungi. The purpose of this research was to demonstrate that the efficiency of transformation can be improved significantly by enhancing acoustic cavitation using tandem (dual-pulse) shock waves. Results revealed that tandem pressure pulses, generated at a delay of 300 μs, increased the transformation efficiency of Aspergillus niger up to 84% in comparison with conventional (single-pulse) shock waves. This methodology may also be useful to obtain new strains required in basic research and biotechnology. PMID:24680880

  11. Biotransformation of germacranolide from Onopordon leptolepies by Aspergillus niger.

    Science.gov (United States)

    Esmaeili, Akbar; Moazami, Nasrin; Rustaiyan, Abdolhossein

    2012-01-01

    Terpenes are present in the essential oils obtained from herbs and spices. They are produced by these plant species as a chemical defense mechanism against phytopathogenic microorganisms. Therefore, terpenes have attracted great attention in the food industry, e.g., they have been used in foods such as cheese as natural preservatives to prevent fungal growth. Herein, we describe the microbial transformation of onopordopicrin (1) by Aspergillus niger. Four product 11α H-dihydroonopordopicrin (2), 11β H-dihydroonopordopicrin (3), 3β-hydroxy-11β H-dihydroonopordopicrin (4), and 14-hydroxy-11β H-dihydroonopordopicrin (5) were obtained. Their structures were identified on the basis of chemical and spectroscopic data. All the four compounds were novel. PMID:22186324

  12. Preparation of 3-deacetyl cephalosporins by Aspergillus niger lipase.

    Science.gov (United States)

    Carrea, G; Corcelli, A; Palmisano, G; Riva, S

    1996-12-20

    Lipase from Aspergillus niger was used for the selective hydrolysis of the 3-O-acetate of cephalosporin C to give an intermediate useful for further chemical elaborations. This lipase was purified to homogeneity and its properties compared with previously published data that present some discrepancies. The lipase proved to be very effective in catalyzing 3-O-acetate hydrolysis and versatile toward substitution on the beta-lactamic ring. In fact, as an example, two other cephalosporinic derivatives, cephalotin and cefotaxime, were efficiently deacetylated. The lipase was immobilized on Eupergit C and employed continuously in either a column or a batch reactor for 2 months without appreciable loss of activity. (c) 1996 John Wiley & Sons, Inc. PMID:18629943

  13. Erratum to: Purification and characterization of a nitrilase from Aspergillus niger

    Czech Academy of Sciences Publication Activity Database

    Kaplan, Ondřej; Vejvoda, Vojtěch; Plíhal, O.; Pompach, P.; Kavan, D.; Bojarová, Pavla; Bezouška, K.; Macková, M.; Cantarella, M.; Jirků, V.; Křen, Vladimír; Martínková, Ludmila

    2013-01-01

    Roč. 97, č. 8 (2013), s. 3745-3746. ISSN 0175-7598 Institutional support: RVO:61388971 Keywords : nitrilase * Aspergillus niger Subject RIV: EE - Microbiology, Virology Impact factor: 3.811, year: 2013

  14. Purification and characterisation of a novel enantioselective epoxide hydrolase from Aspergillus niger M200

    Czech Academy of Sciences Publication Activity Database

    Kotík, Michael; Kyslík, Pavel

    2006-01-01

    Roč. 1760, - (2006), s. 245-252. ISSN 0006-3002 Institutional research plan: CEZ:AV0Z50200510 Keywords : epoxide hydrolase * enantioselectivity * aspergillus niger Subject RIV: EE - Microbiology, Virology

  15. Initial intracellular proteome profile of Aspergillus niger biofilms

    Directory of Open Access Journals (Sweden)

    Gretty K. Villena

    2011-07-01

    Full Text Available An initial profiling of the intracellular proteome of Aspergillus niger ATCC 10864 biofilm cultures developed on polyester cloth was carried out by using 2D-PAGE and MS-TOF analysis and it was compared to the proteome of conventionally grown free-living submerged cultures. A number of 2D-PAGE protein spots from both types of cultures were subjected to MS-TOF analysis and data interrogation of the NCBI nr database available for this species. Proteomic maps showed different expression patterns in both culture systems with differentially expressed proteins in each case. In biofilm cultures, 19% and 32% of the selected protein spots were over- expressed and differentially expressed, respectively. On the contrary, in free-living cultures, 44% and 7% of the selected protein spots were over-expressed and differentially expressed, respectively. Although preliminary, results presented in this paper show that there are significant differences between the proteomes of A. niger biofilm and free-living mycelia. It seems that cell adhesion is the most important stimulus responsible for biofilm development which is the basis of Surface Adhesion Fermentation.

  16. [Aspergillus niger alpha-N-acetylgalactosaminidase: isolation, purification and properties].

    Science.gov (United States)

    Borzova, N V; Varbanets, L D

    2006-01-01

    alpha-N-acetylgalactosaminidase has been isolated from liquid culture of micromycete Aspergillus niger and purified 600 times by ammonium sulphate precipitation followed by ion exchange and gel-filtration chromatography on TSK-gels with specific activity 10.5 U/mg of protein. The preparation was homogenic: its molecular mass by the data of gel-filtration on Sepharose 6B was 430 kDa, on PAAGE in the system of DDSNa--70 kDa. That gives every reason to suppose oligomeric structure of the enzyme molecule. The carbohydrate component, including mannose, galactose, glucosamine and two nonidentified hexosamines was observed in alpha-N-acetylgalactosaminidase. Thermo- and pH- optima were 60 degrees C and pH 3.5, respectively. The enzyme was thermo- and pH-stable, resistant in storage. The enzyme was found to exhibit strict specificity in respect ofglycon. It was shown that enzyme was competitively inhibited by substrate and reaction product. Km and Vmax with respect to nitrophenyl substrate were 1.25 mM and 10.5 mkmole/min/mg of protein. The activity of glycosidase tested was independent of the presence of metal ions. The presence of carboxylic group of C-terminal aminoacid and imidazol group of hystidine in active centre of molecule was established. A number of natural and synthetic substrates were able to activate (50-200%) production of A. niger alpha-N-acetylgalactosaminidase. PMID:17290780

  17. Characterization of oxylipins and dioxygenase genes in the asexual fungus Aspergillus niger

    OpenAIRE

    Kalkhove Stefanie IC; de Vries Ronald P; Wadman Mayken W; Veldink Gerrit A; Vliegenthart Johannes FG

    2009-01-01

    Abstract Background Aspergillus niger is an ascomycetous fungus that is known to reproduce through asexual spores, only. Interestingly, recent genome analysis of A. niger has revealed the presence of a full complement of functional genes related to sexual reproduction 1. An example of such genes are the dioxygenase genes which in Aspergillus nidulans, have been shown to be connected to oxylipin production and regulation of both sexual and asexual sporulation 234. Nevertheless, the presence of...

  18. Cellulolytic enzymes on lignocellulosic substrates in solid state fermentation by Aspergillus niger

    OpenAIRE

    Chandra, M. Subhosh; Viswanath, Buddolla; Reddy, B. Rajasekhar

    2007-01-01

    The production of cellulolytic enzymes by Aspergillus niger on lignocellulosic substrates groundnut fodder, wheat bran, rice bran and sawdust in solid state fermentation in a laboratory scale was compared. Czapek Dox liquid broth amended with cellulose (0.5%) was used to moisten lignocellulosic solid supports for cultivation of Aspergillus niger. The production of filter paperase, carboxymethyl cellulase and -glucosidase were monitored at daily intervals for 5 days. The peak production of the...

  19. The Production of Itaconic Acid from Sweet Potato Peel Using Aspergillus niger and Aspergillus terreus

    Directory of Open Access Journals (Sweden)

    OMOJASOLA PATRICIA FOLAKEMI

    2014-12-01

    Full Text Available 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, ground, pre-treated with alkali and steam, re-dried and used as substrate in media containing mineral salt medium and inocula of A. niger and A. terreus. Fermentation was submerged at pH 5.0; 10% substrate concentration; 10 mL inocula size; temperature 250 C for five days with carboxylmethylcellulose (CMC as control. Optimization experiments were conducted by varying fermentation parameters. Results of physico-chemical analysis revealed carbohydrate 65.9%; sugars 22.60%; protein 5.38%; fibre 3.48%; fat 4.0% ash 4.02% and moisture 8.13%. Itaconic acid yield of 67.67+1.20 mg mL-1 and 70.67+2.60 mg mL-1 produced by A. niger and A. terreus from SPP respectively. The CMC yielded 3.00 +0.6 mg mL-1. Results of the optimization experiments showed higher yields of itaconic acid by A. niger and A. terreus to 112.67+5.20 mg mL-1 and 115.67+5.30 mg mL-1 from SPP respectively at pH 4.0; 10% substrate concentration; 5 mL inocula size on Day-5 of the fermentation. This represented an increase in product yield by both organisms and supports the potential use of this waste for the industrial production of itaconic acid.

  20. The molecular and genetic basis of conidial pigmentation in Aspergillus niger

    DEFF Research Database (Denmark)

    Jørgensen, Thomas R.; Park, Joohae; Arentshorst, Mark;

    2011-01-01

    A characteristic hallmark of Aspergillus niger is the formation of black conidiospores. We have identified four loci involved in spore pigmentation of A. niger by using a combined genomic and classical complementation approach. First, we characterized a newly isolated color mutant, colA, which la...

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

    DEFF Research Database (Denmark)

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

    2007-01-01

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

  2. QCM study of microbially influenced corrosion of aluminium subjected to the influence of Aspergillus niger Tiegh

    OpenAIRE

    Miečinskas, Povilas; Leinartas, Konstantinas; Uksienė, Virginija; Lugauskas, Albinas; Ramanauskas, Rimantas; Juzeliūnas, Eimutis

    2006-01-01

    Aspergillus niger Tiegh., a filamentous ascomycete fungus, was isolated from metal samples exposed to marine, rural and urban sites in Lithuania. Al samples prepared as glued foil electrodes on quartz crystal microbalance were subjected to a long-term influence (three months) of A. niger under laboratory conditions in humid atmosphere. The comparison of the QCM data between the samples affected by A. niger and abiotic ones showed a marked increase in the electrode mass due to the development ...

  3. Transcriptomic comparison of Aspergillus niger growing on two different sugars reveals coordinated regulation of the secretory pathway

    DEFF Research Database (Denmark)

    Jørgensen, Thomas R; Goosen, Theo; Hondel, Cees A M J J van den;

    2009-01-01

    BACKGROUND: The filamentous fungus, Aspergillus niger, responds to nutrient availability by modulating secretion of various substrate degrading hydrolases. This ability has made it an important organism in industrial production of secreted glycoproteins. The recent publication of the A. niger...

  4. AMYLASE PRODUCTION BY ASPERGILLUS NIGER UNDER SOLID STATE FERMENTATION USING AGROINDUSTRIAL WASTES

    Directory of Open Access Journals (Sweden)

    Suganthi

    2011-02-01

    Full Text Available Solid state fermentation holds tremendous potentials for the production of the enzyme amylase by Aspergillus niger. Different solid substrates like rice bran, wheat bran, black gram bran, coconut oil cake, gingely oil cake and groundnut oil cake are rich in starch. These agro industrial residues are cheap raw materials for amylase production. Aspergillus niger BAN3E was identified to be the best producer of amylase. When A. niger BAN3E was incubated for 6 days at 37°C it showed high yield of amylase in groundnut oil cake substratein solid state fermentation. Sucrose and nitrogen improved the yield in the same medium.

  5. AMYLASE PRODUCTION BY ASPERGILLUS NIGER UNDER SOLID STATE FERMENTATION USING AGROINDUSTRIAL WASTES

    OpenAIRE

    Suganthi; R., Benazir,; J.F., Santhi,; R., Ramesh Kumar,; V., Anjana Hari,; Nitya Meenakshi; Nidhiya; K. A., Kavitha,; G., Lakshmi, R.

    2011-01-01

    Solid state fermentation holds tremendous potentials for the production of the enzyme amylase by Aspergillus niger. Different solid substrates like rice bran, wheat bran, black gram bran, coconut oil cake, gingely oil cake and groundnut oil cake are rich in starch. These agro industrial residues are cheap raw materials for amylase production. Aspergillus niger BAN3E was identified to be the best producer of amylase. When A. niger BAN3E was incubated for 6 days at 37°C it showed high yield of ...

  6. 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

  7. Nickel accumulation and nickel oxalate precipitation by Aspergillus niger.

    Science.gov (United States)

    Magyarosy, A; Laidlaw, R D; Kilaas, R; Echer, C; Clark, D S; Keasling, J D

    2002-07-01

    A strain of Aspergillus niger isolated from a metal-contaminated soil was able to grow in the presence of cadmium, chromium, cobalt, copper, and unusually high levels of nickel on solid (8.0 mM) and in liquid (6.5 mM) media. This fungus removed >98% of the nickel from liquid medium after 100 h of growth but did not remove the other metals, as determined by inductively coupled plasma spectroscopy. Experiments with non-growing, live fungal biomass showed that nickel removal was not due to biosorption alone, as little nickel was bound to the biomass at the pH values tested. Furthermore, when the protonophore carbonyl cyanide p-(trifluoremetoxy) phenyl hydrazone (FCCP) was added to the actively growing fungus nickel removal was inhibited, supporting the hypothesis that energy metabolism is essential for metal removal. Analytical electron microscopy of thin-sectioned fungal biomass revealed that metal removed from the broth was localized in the form of small rectangular crystals associated with the cell walls and also inside the cell. X-ray and electron diffraction analysis showed that these crystals were nickel oxalate dihydrate. PMID:12111174

  8. The effects of types of media on uranium leaching using metabolite of Aspergillus niger

    International Nuclear Information System (INIS)

    To investigate the influences of different media to uranium leaching applying with metabolite of Aspergillus niger, PSA and glucose-steepwater medium were used for the culture of Aspergillus niger, and the metabolite of Aspergillus niger with different pH value produced in the diverse culture temperature were obtained which was applied on the tests of uranium leaching as leaching agent. The test results show that the maximum leaching rate is 83.05% when the leaching agent is the metabolite of Aspergillus niger produced by PSA, as for the glucose- steepwater medium, the maximum leaching rate is 68.20%. The pH value of the metabolite of Aspergillus niger of the two kinds of media has a significant effect on the leaching rate. When PSA is adopted, the best leaching rate appears at the pH value of metabolite ranging from 2.0 to 2.5, and as for the glucose-steepwater medium, the pH value is below 2.1. (authors)

  9. An Antifungal Role of Hydrogen Sulfide on the Postharvest Pathogens Aspergillus niger and Penicillium italicum

    OpenAIRE

    Liu-Hui Fu; Kang-Di Hu; Lan-Ying Hu; Yan-Hong Li; Liang-Bin Hu; Hong Yan; Yong-Sheng Liu; Hua Zhang

    2014-01-01

    In this research, the antifungal role of hydrogen sulfide (H2S) on the postharvest pathogens Aspergillus niger and Penicillium italicum growing on fruits and under culture conditions on defined media was investigated. Our results show that H2S, released by sodium hydrosulfide (NaHS) effectively reduced the postharvest decay of fruits induced by A. niger and P. italicum. Furthermore, H2S inhibited spore germination, germ tube elongation, mycelial growth, and produced abnormal mycelial contract...

  10. The apple pulp waste used as a nourishing base by Aspergillus niger

    OpenAIRE

    Mojsov, Kiro

    2011-01-01

    The aim of this work was to develop a low cost process for apple pulp utilization. This actual waste from food and agriculture industry was used as a nourishing base by Aspergillus niger MK-15. The apple pulp combined with corn flour and simple mineral salts was utilized as a nourishing base by submerged production of pectinolytic enzymes by the fungus Aspergillus niger MK-15. Different concentration on apple pulp (1%; 2%; and 3%, w/v) and different pH initial on the bases (4; 5 and 6) were s...

  11. The infrared spectral transmittance of Aspergillus niger spore aggregated particle swarm

    Science.gov (United States)

    Zhao, Xinying; Hu, Yihua; Gu, Youlin; Li, Le

    2015-10-01

    Microorganism aggregated particle swarm, which is quite an important composition of complex media environment, can be developed as a new kind of infrared functional materials. Current researches mainly focus on the optical properties of single microorganism particle. As for the swarm, especially the microorganism aggregated particle swarm, a more accurate simulation model should be proposed to calculate its extinction effect. At the same time, certain parameters deserve to be discussed, which helps to better develop the microorganism aggregated particle swarm as a new kind of infrared functional materials. In this paper, take Aspergillus Niger spore as an example. On the one hand, a new calculation model is established. Firstly, the cluster-cluster aggregation (CCA) model is used to simulate the structure of Aspergillus Niger spore aggregated particle. Secondly, the single scattering extinction parameters for Aspergillus Niger spore aggregated particle are calculated by using the discrete dipole approximation (DDA) method. Thirdly, the transmittance of Aspergillus Niger spore aggregated particle swarm is simulated by using Monte Carlo method. On the other hand, based on the model proposed above, what influences can wavelength causes has been studied, including the spectral distribution of scattering intensity of Aspergillus Niger spore aggregated particle and the infrared spectral transmittance of the aggregated particle swarm within the range of 8~14μm incident infrared wavelengths. Numerical results indicate that the scattering intensity of Aspergillus Niger spore aggregated particle reduces with the increase of incident wavelengths at each scattering angle. Scattering energy mainly concentrates on the scattering angle between 0~40°, forward scattering has an obvious effect. In addition, the infrared transmittance of Aspergillus Niger spore aggregated particle swarm goes up with the increase of incident wavelengths. However, some turning points of the trend

  12. Effect of Temperature on Production of Ochratoxin A by Aspergillus niger in Orange Juice

    OpenAIRE

    Marino, Andreana; Fiorentino, Caterina; Spataro, Francesca; Nostro, Antonia

    2014-01-01

    This challenging study was carried out to evaluate the temporal production of ochratoxin A (OTA) by Aspergillus niger ATCC 16404 and wild type A. niger AM at different temperatures in fresh squeezed orange juice (Citrus sinensis [L.] Osbeck cv Tarocco). Each strain, inoculated into the filtered orange juice, was incubated at 4°C, 20°C, and 26°C for 28 days. In the juice, at 26°C and 20°C, the concentration of A. niger ATCC 16404 increased by more than 2 log10 up to the 21st day. At 4°C it rem...

  13. Characterization of oxylipins and dioxygenase genes in the asexual fungus Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Kalkhove Stefanie IC

    2009-03-01

    Full Text Available Abstract Background Aspergillus niger is an ascomycetous fungus that is known to reproduce through asexual spores, only. Interestingly, recent genome analysis of A. niger has revealed the presence of a full complement of functional genes related to sexual reproduction 1. An example of such genes are the dioxygenase genes which in Aspergillus nidulans, have been shown to be connected to oxylipin production and regulation of both sexual and asexual sporulation 234. Nevertheless, the presence of sex related genes alone does not confirm sexual sporulation in A. niger. Results The current study shows experimentally that A. niger produces the oxylipins 8,11-dihydroxy octadecadienoic acid (8,11-diHOD, 5,8-dihydroxy octadecadienoic acid (5,8-diHOD, lactonized 5,8-diHOD, 8-hydroxy octadecadienoic acid (8-HOD, 10-hydroxy octadecadienoic acid (10-HOD, small amounts of 8-hydroxy octadecamonoenoic acid (8-HOM, 9-hydroxy octadecadienoic acid (9-HOD and 13-hydroxy octadecadienoic acid (13-HOD. Importantly, this study shows that the A. niger genome contains three putative dioxygenase genes, ppoA, ppoC and ppoD. Expression analysis confirmed that all three genes are indeed expressed under the conditions tested. Conclusion A. niger produces the same oxylipins and has similar dioxygenase genes as A. nidulans. Their presence could point towards the existence of sexual reproduction in A. niger or a broader role for the gene products in physiology, than just sexual development.

  14. Transcription factors as targets for improving Aspergillus niger as cell factory

    DEFF Research Database (Denmark)

    Poulsen, Lars; Bruno, K.S.; Thykær, Jette; Baker, S.E.; Eliasson Lantz, Anna

    ., 2008). In the present study the effect of modulation of transcription factors in Aspergillus niger, which is an industrially important micro-organism used in various processes including organic acid and enzyme production, was investigated. The strategy described in this work focuses on regulation...

  15. Characterization of a foldase, protein disulfide isomerase A, in the protein secretory pathway of Aspergillus niger

    NARCIS (Netherlands)

    Ngiam, C.; Jeenes, D.J.; Punt, P.J.; Hondel, C.A.M.J.J. van den; Archer, D.B.

    2000-01-01

    Protein disulfide isomerase (PDI) is important in assisting the folding and maturation of secretory proteins in eukaryotes. A gene, pdiA, encoding PDIA was previously isolated from Aspergillus niger, and we report its functional characterization here. Functional analysis of PDIA showed that it catal

  16. The transcriptomic fingerprint of glucoamylase over-expression in Aspergillus niger

    NARCIS (Netherlands)

    Kwon, M.J.; Jorgensen, T.R.; Nitsche, B.M.; Arentshorst, M.; Park, J.; Ram, A.F.J.; Meyer, V.

    2012-01-01

    Background: Filamentous fungi such as Aspergillus niger are well known for their exceptionally high capacity for secretion of proteins, organic acids, and secondary metabolites and they are therefore used in biotechnology as versatile microbial production platforms. However, system-wide insights int

  17. Formation of Sclerotia and Production of Indoloterpenes by Aspergillus niger and Other Species in Section Nigri

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian; Petersen, Lene Maj; Lyhne, Ellen Kirstine; Larsen, Thomas Ostenfeld

    2014-01-01

    reported to produce sclerotia, and is thought to be a purely asexual organism. Here we report, for the first time, the production of sclerotia by certain strains of Aspergillus niger when grown on CYA agar with raisins, or on other fruits or on rice. Up to 11 apolar indoloterpenes of the aflavinine type...

  18. Induction, isolation, and characterization of aspergillus niger mutant strains producing elevated levels of beta-galactosidase.

    OpenAIRE

    Nevalainen, K M

    1981-01-01

    An Aspergillus niger mutant strain, VTT-D-80144, with an improvement of three- to fourfold in the production of extracellular beta-galactosidase was isolated after mutagenesis. The production of beta-galactosidase by this mutant was unaffected by fermentor size, and the enzyme was also suitable for immobilization.

  19. NIGERLYSINTM, HEMOLYSIN PRODUCED BY ASPERGILLUS NIGER, CAUSES LETHALITY OF PRIMARY RAT CORTICAL NEURONAL CELLS IN VITRO

    Science.gov (United States)

    Aspergillus niger produced a proteinaceous hemolysin, nigerlysinTM when incubated on sheep's blood agar at both 23° C and 37°C. Nigerlysin was purified from tryptic soy broth culture filtrate. Purified nigerlysin has a molecular weight of approximately 72 kDa, with an...

  20. Crystallization and preliminary X-ray crystallographic analysis of recombinant -mannosidase from Aspergillus niger

    Czech Academy of Sciences Publication Activity Database

    Demo, G.; Fliedrová, Barbora; Weignerová, Lenka; Wimmerová, M.

    2013-01-01

    Roč. 69, č. 3 (2013), s. 288-291. ISSN 1744-3091 R&D Projects: GA ČR GAP207/10/0321; GA MŠk(CZ) 7E11011 Institutional support: RVO:61388971 Keywords : b-mannosidase * Aspergillus niger Subject RIV: CE - Biochemistry Impact factor: 0.568, year: 2013

  1. Induction, purification and characterization of alfa-N-acetylgalactosaminidase from Aspergillus Niger

    Czech Academy of Sciences Publication Activity Database

    Weignerová, Lenka; Filipi, Tomáš; Manglová, Dana; Křen, Vladimír

    2008-01-01

    Roč. 79, č. 5 (2008), s. 769-774. ISSN 0175-7598 R&D Projects: GA MŠk(CZ) LC06010; GA ČR GA203/05/0172 Institutional research plan: CEZ:AV0Z50200510 Keywords : aspergillus niger * glycosidase library Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.569, year: 2008

  2. Elucidation of the biosynthesis of meroterpenoid yanuthone D in Aspergillus Niger

    DEFF Research Database (Denmark)

    Holm, Dorte Koefoed; Petersen, Lene Maj; Klitgaard, Andreas;

    2012-01-01

    We have elucidated the mode of biosynthesis of the meroterpenoid compound Yanuthone D in Aspergillus niger. We have successfully deleted all cluster genes, and identified a number of intermediates. Structures of the intermediates were solved using a combined approach comprising classical 1D- and 2D...

  3. Glucoamylase : green fluorescent protein fusions to monitor protein secretion in Aspergillus niger

    NARCIS (Netherlands)

    Gordon, C.L.; Khalaj, V.; Ram, A.F.J.; Archer, D.B.; Brookman, J.L.; Trinci, A.P.J.; Jeenes, D.J.; Doonan, J.H.; Wells, B.; Punt, P.J.; Hondel, C.A.M.J.J. van den; Robson, G.D.

    2000-01-01

    A glucoamylase: :green fluorescent protein fusion (GLA: :sGFP) was constructed which allows the green fluorescent protein to be used as an in vivo reporter of protein secretion in Aspergillus niger. Two secretory fusions were designed for secretion of GLA: :sGFP which employed slightly different len

  4. Study of the glucoamylase promoter in Aspergillus niger using green fluorescent protein

    NARCIS (Netherlands)

    Santerre Henriksen, A.L.; Even, S.; Müller, C.; Punt, P.J.; Hondel, C.A.M.J.J. van den; Nielsen, J.

    1999-01-01

    An Aspergillus niger strain expressing a red-shifted green fluorescent protein (GFP) in the cytoplasm under the control of the glucoamylase promoter (PglaA) was characterized with respect to its physiology and morphology. Although xylose acted as a repressor carbon source during batch cultivations,

  5. The effect of organic nitrogen sources on recombinant glucoamylase production by Aspergillus niger in chemostat culture

    NARCIS (Netherlands)

    Swift, R.J.; Karandikar, A.; Griffen, A.M.; Punt, P.J.; Hondel, C.A.M.J.J. van den; Robson, G.D.; Trinci, A.P.J.; Wiebe, M.G.

    2000-01-01

    Aspergillus niger B1, a recombinant strain carrying 20 extra copies of the native glucoamylase gene, was grown in glucose-limited chemostat cultures supplemented with various organic nitrogen sources (dilution rate 0.12 ± 0.01 h-1, pH 5.4). In cultures supplemented with L-alanine, L-methionine, casa

  6. Overexpression of isocitrate lyase-glyoxylate bypass influence on metabolism in Aspergillus niger

    DEFF Research Database (Denmark)

    Meijer, Susan Lisette; Otero, José Manuel; Olivares Hernandez, Roberto;

    2009-01-01

    In order to improve the production of succinate and malate by the filamentous fungus Aspergillus niger the activity of the glyoxylate bypass pathway was increased by over-expression of the isocitrate lyase (icl) gene. The hypothesis was that when isocitrate lyase was up-regulated the flux towards...

  7. Overproduction of the Aspergillus niger feruloyl esterase for pulp bleaching application

    NARCIS (Netherlands)

    Record, E.; Asther, M.; Sigoillot, C.; Pagès, S.; Punt, P.J.; Delattre, M.; Haon, M.; Hondel, C.A.M.J.J. van den; Sigoillot, J.C.; Lesage-Meessen, L.; Asther, M.

    2003-01-01

    A well-known industrial fungus for enzyme production, Aspergillus niger, was selected to produce the feruloyl esterase FAEA by homologous overexpression for pulp bleaching application. The gpd gene promoter was used to drive FAEA expression. Changing the nature and concentration of the carbon source

  8. Regulation and control of L-arabinose catabolism in Aspergillus niger

    NARCIS (Netherlands)

    Groot, de M.J.L.

    2005-01-01

    This thesis describes studies on the biochemical properties and regulation of L-arabinose metabolism and arabinan degrading enzymes of Aspergillus niger. We focused on the investigation of the catabolic pathway, firstly by isolating pathway specific regulatory mutants using a newly developed selecti

  9. Enzymatic Comparisons of Aspergillus niger PhyA and Escherichia coli AppA2 Phytases

    Science.gov (United States)

    This study was to compare three phytase activity assays and kinetics of Aspergillus niger PhyA and Escherichia coli AppA2 phytases expressed in Pichia pastoris at the observed stomach pH of 3.5. In Experiment 1, equivalent phytase activities in the crude preparations of PhyA and AppA2 were tested ...

  10. Aspergillus niger DLFCC-90 Rhamnoside Hydrolase, a New Type of Flavonoid Glycoside Hydrolase

    OpenAIRE

    Liu, Tingqiang; Yu, Hongshan; Zhang, Chunzhi; Lu, Mingchun; Piao, Yongzhe; Ohba, Masashi; Tang, Minqian; Yuan, Xiaodong; Wei, Shenghua; Wang, Kan; Ma, Anzhou; Feng, Xue; Qin, Siqing; Mukai, Chisato; Tsuji, Akira

    2012-01-01

    A novel rutin-α-l-rhamnosidase hydrolyzing α-l-rhamnoside of rutin, naringin, and hesperidin was purified and characterized from Aspergillus niger DLFCC-90, and the gene encoding this enzyme, which is highly homologous to the α-amylase gene, was cloned and expressed in Pichia pastoris GS115. The novel enzyme was classified in glycoside-hydrolase (GH) family 13.

  11. LOCALIZATION OF GROWTH AND SECRETION OF PROTEINS IN ASPERGILLUS-NIGER

    NARCIS (Netherlands)

    WOSTEN, HAB; MOUKHA, SM; SIETSMA, JH; WESSELS, JGH

    1991-01-01

    Hyphal growth and secretion of proteins in Aspergillus niger were studied using a new method of culturing the fungus between perforated membranes which allows visualization of both parameters. At the colony level the sites of occurrence of growth and general protein secretion were correlated. In 4-d

  12. Endoplasmic reticulum stress leads to the selective transcriptional downregulation of the glucoamylase gene in Aspergillus niger

    NARCIS (Netherlands)

    Al-Sheikh, H.; Watson, A.J.; Lacey, G.A.; Punt, P.J.; MacKenzie, D.A.; Jeenes, D.J.; Pakula, T.; Penttilä, M.; Alcocer, M.J.C.; Archer, D.B.

    2004-01-01

    We describe a new endoplasmic reticulum (ER)-associated stress response in the filamentous fungus Aspergillus niger. The inhibition of protein folding within the ER leads to cellular responses known collectively as the unfolded protein response (UPR) and we show that the selective transcriptional do

  13. Protection of Aspergillus niger cellulases by urea during growth on glucose or glycerol supplemented media.

    Science.gov (United States)

    Gokhale, D V; Patil, S G; Bastawde, K B

    1992-10-01

    The cellulase enzymes of Aspergillus niger were found to undergo catabolite repression in the presence of glucose and glycerol accompanied by sudden drop in pH of the fermentation medium below 2.0. This sudden drop in pH caused inactivation of cellulolytic enzymes produced by Aspergillus niger. The supplementation of nitrogen sources, especially urea, protects A. niger cellulases from inactivation caused by a sudden drop in pH, since urea helped to maintain the pH of the fermentation medium between 3.5 and 4.5. The role of urea in the protection of cellulase was more prominent when it was used in combination with glycerol (5%). PMID:1288413

  14. EFFECT OF GAMMA IRRADIATION AND ENVIRONMENTAL FACTORS ON -AMYLASE PRODUCTION BY ASPERGILLUS NIGER AND ASPERGILLUS ORYZAE FROM SOME AGRICULTURAL WASTES

    International Nuclear Information System (INIS)

    Amylases are one of the most important and oldest industrial enzymes. The optimization of production of α -amylase from Aspergillus niger and Aspergillus oryzae fungi, using different agro-wastes as sole carbon sources, was performed. The highest productivity of α -amylase by the two organisms was recorded at pH 6 and incubation temperature at 300C when the two organisms were grown on potato peels (PPs) and/or wheat straw (Ws) after days of cultivation. Pre-treated PPs and Ws with 20 kGy gave the best enzyme productivity by the two organisms compared with untreated ones. Also, exposing the inoculums of A. niger and A.oryzae to 0.5 and 0.75 kGy, respectively, led to enhancement of α-amylase to 48 and 46 μ/ml, respectively

  15. Effect of different substrates on the production of amino acids by aspergillus niger

    International Nuclear Information System (INIS)

    In the present work, attempts were made to utilize sugarcane waste as carbon source for amino acid production by Aspergillus nigher. Different concentration (0.3N and 0.6N) of H/sub 2/SO/sub 4/ and NH/sub 4/OH were used to hydrolyze lignocellulosic material of the sugar cane bagasse to release the fermentable sugar, which were incorporated with mineral medium for the growth of Aspergillus niger and amino acid production. Whereas, molasses was diluted in 2.5% and 5% and was mixed with mineral medium for amino acid production by Aspergillus niger. The results were compaired with sugar cane bagasse for amino acid production. Molasses 5% was found better substrate for higher production of amino acids in comparison to hydrolysates of sugar can bagasse. (author)

  16. Phytase Production by Aspergillus niger CFR 335 and Aspergillus ficuum SGA 01 through Submerged and Solid-State Fermentation

    Directory of Open Access Journals (Sweden)

    Gunashree B. Shivanna

    2014-01-01

    Full Text Available Fermentation is one of the industrially important processes for the development of microbial metabolites that has immense applications in various fields. This has prompted to employ fermentation as a major technique in the production of phytase from microbial source. In this study, a comparison was made between submerged (SmF and solid-state fermentations (SSF for the production of phytase from Aspergillus niger CFR 335 and Aspergillus ficuum SGA 01. It was found that both the fungi were capable of producing maximum phytase on 5th day of incubation in both submerged and solid-state fermentation media. Aspergillus niger CFR 335 and A. ficuum produced a maximum of 60.6 U/gds and 38 U/gds of the enzyme, respectively, in wheat bran solid substrate medium. Enhancement in the enzyme level (76 and 50.7 U/gds was found when grown in a combined solid substrate medium comprising wheat bran, rice bran, and groundnut cake in the ratio of 2 : 1 : 1. A maximum of 9.6 and 8.2 U/mL of enzyme activity was observed in SmF by A. niger CFR 335 and A.ficuum, respectively, when grown in potato dextrose broth.

  17. CHANGES IN PHENOLIC CONTENTS OF SAPOTA PULP (ACHRAS SAPOTA L. DUE TO DIFFERENT ISOLATES OF ASPERGILLUS NIGER

    Directory of Open Access Journals (Sweden)

    Pradnya M. Wagh and U. N. Bhale1

    2012-06-01

    Full Text Available During storage conditions Achras sapota gets infected by several fungal diseases like sour rot (Geotrichum candidum, Cladosporium rot, (Cladosporium oxysporum, Blue mould rot (Penicillium itallicum, Rhizopus rot, Aspergillus niger rot etc. Among these diseases Aspergillus niger rot is very serious disease and it causes changes in biochemical contents of sapota pulp. Phenols are said to offer resistance to diseases and pests in plants. In present investigation spore suspension of Aspergillus niger isolates were inoculated in same aged and surface sterilized ripened sapotas of two ultivars i.e. Cricket ball and Kali patti from Thane district of Mahahashtra state. After seven days change in phenolic content was estimated with the Folin-Ciocalteau method. Phenolic content was found to be decreased significantly due to all 5 isolates of Aspergillus niger in three sapota cultivars.

  18. Submerged Conidiation and Product Formation by Aspergillus niger at Low Specific Growth Rates Are Affected in Aerial Developmental Mutants

    NARCIS (Netherlands)

    Jørgensen, T.R.; Nielsen, K.F.; Arentshorst, M.; Park, J.; Van den Hondel, C.A.; Frisvad, J.C.; Ram, A.F.

    2011-01-01

    Exposure to an aerial environment or severe nutrient limitation induces asexual differentiation in filamentous fungi. Submerged cultivation of Aspergillus niger in carbon- and energy-limited retentostat cultures both induces and fuels conidiation. Physiological and transcriptomic analyses have revea

  19. Assessment of the pectinolytic network of Aspergillus niger by functional genomics : insights from the transcriptome

    OpenAIRE

    Martens-Uzunova, E S

    2008-01-01

    More than a century ago, in 1889, A. Fernbach presented a detailed report about the invertase of Aspergillus niger in the third edition of “Annales De L'institut Pasteur”. Since then, many of the enzymes secreted by A. niger have found a broad range of applications, and today they are produced on an industrial scale. This filamentous fungus is also used as a primary source for the production of organic acids and other economically important metabolites. Although, many of these fermentation pr...

  20. Characterization of a starch-hydrolyzing α-amylase produced by Aspergillus niger WLB42 mutated by ethyl methanesulfonate treatment

    OpenAIRE

    Wang, Shihui; Lin, Chaoyang; Liu, Yun; Shen, Zhicheng; Jeyaseelan, Jenasia; Qin, Wensheng

    2016-01-01

    Aspergillus niger is the most commonly used fungus for commercial amylase production, the increase of amylase activity will be beneficial to the amylase industry. Herein we report a high α-amylase producing (HAP) A. niger WLB42 mutated from A. niger A4 by ethyl methanesulfonate treatment. The fermentation conditions for the amylase production were optimized. The results showed that both the amylase activity and total protein content reached highest after 48-h incubation in liquid medium using...

  1. On the safety of Aspergillus niger - a review

    DEFF Research Database (Denmark)

    Schuster, E.; Dunn-Coleman, N.; Frisvad, Jens Christian;

    2002-01-01

    , compared with other filamentous fungi, it does not stand out as a particular problem concerning allergy or mycopathology. A few medical cases, e.g. lung infections, have been reported, but always in severely immunocompromised patients. In tropical areas, ear infections (otomycosis) do occur due to A. niger...

  2. Gluconate formation and polyol metabolism in Aspergillus niger.

    NARCIS (Netherlands)

    Witteveen, C.F.B.

    1993-01-01

    The capacity of A.niger to accumulate metabolites is remarkable. Under all conditions polyols accumulate in the cell and when mycelium in later developmental stages is considered, depending on the carbon source, aeration and external pH, polyols and/or organic acids can be formed in a very efficient

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

    OpenAIRE

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

    2015-01-01

    Aspergillus species are highly abundant fungi worldwide. Their conidia are among the most dominant fungal spores in the air. Conidia are formed in chains on the vesicle of the asexual reproductive structure called the conidiophore. Here, it is shown that the velvet protein VeA of Aspergillus niger maximizes the diameter of the vesicle and the spore chain length. The length and width of the conidiophore stalk and vesicle were reduced nearly twofold in a ΔveA strain. The latter implies a fourfo...

  4. A high yield of amylase from Aspergillus niger by the effect of gamma irradiation

    International Nuclear Information System (INIS)

    When irradiated rice was used as a media for Aspergillus niger a noticeable increase of amylase production was observed. Molecular degradation of starch molecules did occure, and an increase in starch acidity and solubility was noticed, whereas a marked decrease in viscosity as well as swelling capacity was observed. Gelatinization time and temperature of irradiated starch became shorter or lower resp. These results showed that internal changes in irradiated starch molecules and an alteration in its molecular configuration occured. They may affect the pathway of the growth of the fungi Aspergillus niger. When the amount of amylase was determined by measuring enzyme activity, it was observed that amylases in the irradiated media were higher than in the control media. (orig.)

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

    Science.gov (United States)

    Florencio, Camila; Cunha, Fernanda M; Badino, Alberto C; Farinas, Cristiane S; Ximenes, Eduardo; Ladisch, Michael R

    2016-09-01

    The cultivation procedure and the fungal strain applied for enzyme production may influence levels and profile of the proteins produced. The proteomic analysis data presented here provide critical information to compare proteins secreted by Trichoderma reesei and Aspergillus niger when cultivated through submerged and sequential fermentation processes, using steam-explosion sugarcane bagasse as inducer for enzyme production. The proteins were organized according to the families described in CAZy database as cellulases, hemicellulases, proteases/peptidases, cell-wall-protein, lipases, others (catalase, esterase, etc.), glycoside hydrolases families, predicted and hypothetical proteins. Further detailed analysis of this data is provided in "Secretome analysis of Trichoderma reesei and Aspergillus niger cultivated by submerged and sequential fermentation process: enzyme production for sugarcane bagasse hydrolysis" C. Florencio, F.M. Cunha, A.C Badino, C.S. Farinas, E. Ximenes, M.R. Ladisch (2016) [1]. PMID:27419196

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

    Directory of Open Access Journals (Sweden)

    Jorge Alberto Vieira Costa

    2007-09-01

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

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

    International Nuclear Information System (INIS)

    Local citric acid producer of fungal strain Aspergillus niger have been successfully isolated from stale bread and onion. The isolates, designated as SB 1 and NN I showed a potential performance for citric acid production of 49% and 52% yield respectively, in shake flask studies. The strain improvement on NN1 was carried out by radiation induced mutation by gamma rays at LD50 of 1.28 kGy

  8. Production and action pattern of inulinase from Aspergillus Niger-245: hydrolysis of inulin from several sources

    OpenAIRE

    Cruz Vinícius D?Arcadia; Belote Juliana Gisele; Belline Márcia Zilioli; Cruz Rubens

    1998-01-01

    A strain of Aspergillus niger isolated from soil samples showed great capacity to produce extracellular inulinase. Although the enzyme has been synthesized in presence of monosaccharides, sucrose and sugar cane molasse, the productivity was significantly higher (p<0.05) when the microorganism was inoculated in media formulated with dahlia extract and pure inulin, as carbon sources. With regard to the nitrogen source, the best results were obtained with casein and other sources of proteic n...

  9. OPTIMIZATION OF EXTRACELLULAR ACID PROTEASE PRODUCTION FROM ASPERGILLUS NIGER BY FACTORIAL DESIGN

    OpenAIRE

    Vishalkirti Vijay Kalaskar; Narayanan Kasinathan; Volety Mallikarjuna Subrahmanyam; Josyula Venkata Rao

    2014-01-01

    The cultural conditions for acid protease production by Aspergillus niger was optimised using factorial design experiments and one factor-at-a time approach. In the production medium casein served as substrate and protease activity was measured in terms of tyrosine yield. The yield was further improved through UV mutation. Tyrosine yield amounted to 29.22 mg / g on casein substrate. Protease from this microbial strain was mesophilic. The enzyme was stable over a wide temperature range (30 to ...

  10. Metabolic pathway reconstruction of eugenol to vanillin bioconversion in Aspergillus niger

    OpenAIRE

    Srivastava, Suchita; Luqman, Suaib; Khan, Feroz; Chanotiya, Chandan S; Darokar, Mahendra P

    2010-01-01

    Identification of missing genes or proteins participating in the metabolic pathways as enzymes are of great interest. One such class of pathway is involved in the eugenol to vanillin bioconversion. Our goal is to develop an integral approach for identifying the topology of a reference or known pathway in other organism. We successfully identify the missing enzymes and then reconstruct the vanillin biosynthetic pathway in Aspergillus niger. The procedure combines enzyme sequence similarity sea...

  11. Facile production of Aspergillus niger α-N-acetylgalactosaminidase in yeast

    Czech Academy of Sciences Publication Activity Database

    Mrázek, Hynek; Benada, Oldřich; Man, Petr; Vaněk, O.; Křen, Vladimír; Bezouška, Karel; Weignerová, Lenka

    2012-01-01

    Roč. 81, č. 1 (2012), s. 106-114. ISSN 1046-5928 R&D Projects: GA MŠk 1M0505; GA ČR GAP207/10/0321; GA ČR GD305/09/H008; GA ČR GA303/09/0477 Institutional research plan: CEZ:AV0Z50200510 Keywords : Aspergillus niger * alpha-N-Acetylgalactosaminidase * Expression Subject RIV: CE - Biochemistry Impact factor: 1.429, year: 2012

  12. Aspergillus niger peritonitis in a patient on continuous ambulatory peritoneal dialysis

    Directory of Open Access Journals (Sweden)

    Usha Kalawat

    2013-07-01

    Full Text Available Fungal peritonitis is an uncommon condition which is associated with high morbidity and mortality in patients on continuous ambulatory peritoneal dialysis (CAPD. It is associated with several complications and many of the patients who develop this condition are unable to resume CAPD treatment and have to shift to haemodialysis. Here we report the rare occurrence of fungal peritonitis due to Aspergillus niger in a patient on CAPD.

  13. Fermentasi Etanol dari Limbah Padat Tapioka (Onggok) oleh Aspergillus niger dan Zymomonas mobilis

    OpenAIRE

    RATNA SETYANINGSIH; ARI SUSILOWATI; SITI JUARIAH

    2004-01-01

    The aims of this research were to know the best concentration of onggokflour to produce maximum reduction sugar concentration by Aspergillus niger and efficiency of ethanol production from reduction sugar as the product of onggok flour saccharification by Zymomonas mobilis, and the ethanol concentration which produced. The framework of this research was cassava starch in onggok can be used as substance which yielded ethanol by fermentation. The ethanol yielded serves as an alternative substit...

  14. Mutagenesis and mitotic recombination in Aspergillus niger, an expedition from gene to genome

    OpenAIRE

    Vondervoort, Peter Jozef Ida van de

    2007-01-01

    Aspergillus niger is a cosmopolitan fungus and its spores can be found in air and soil worldwide. This saprophyte is used in food biotechnology for the production of proteins, mainly enzymes and for the production of organic acids. In the production of proteins, several problems are encountered such as repressed gene-expression, morphologic and genetic instability and undesired metabolite accumulation. To find solutions to these problems, often mutagenesis and mitotic recombination have been ...

  15. Mild hydrolysis of nitriles by the immobilized nitrilase from Aspergillus niger K10

    Czech Academy of Sciences Publication Activity Database

    Vejvoda, Vojtěch; Kaplan, Ondřej; Bezouška, K.; Martínková, Ludmila

    2006-01-01

    Roč. 39, - (2006), s. 55-58. ISSN 1381-1177 R&D Projects: GA AV ČR IAA4020213; GA ČR GA203/05/2267; GA MŠk OC D25.001 Institutional research plan: CEZ:AV0Z50200510 Keywords : nitrilase * aspergillus niger * benzonitrile Subject RIV: EE - Microbiology, Virology Impact factor: 2.149, year: 2006

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

    OpenAIRE

    Georgi Todorov Dobrev; Boriana Yordanova Zhekova

    2012-01-01

    An extracellular endoglucanase was isolated from the culture liquid of xylanase producing strain Aspergillus niger B03. The enzyme was purified to a homogenous form, using consecutive ultrafiltration, anion exchange chromatography, and gel filtration. Endoglucanase was a monomer protein with a molecular weight of 26,900 Da determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and 28,800 Da determined by gel filtration. The optimal pH and temperature values for the enzyme ac...

  17. Comparative studies on biofilm development by Aspergillus niger on polyester sheet and muslin cloth

    OpenAIRE

    Nitin Verma; Mukesh C.Bansal; Vivek kumar

    2010-01-01

    Filamentous fungi are naturally adapted to adhere on the surfaces in submerged cultures. Cell adhesion plays a vital role in biofilm development in submerged cultures. The objective of the present study is to evaluate the growth rate of Aspergillus on the polyester sheet and muslin cloth with and without solid support in submerged cultures. The growth of A. niger was observed to be high in polyester sheet when compared with muslin cloth.

  18. Evidence for a cytoplasmic pathway of oxalate biosynthesis in Aspergillus niger

    International Nuclear Information System (INIS)

    Oxalate accumulation of up to 8 g/liter was induced in Aspergillus niger by shifting the pH from 6 to 8. This required the presence of P/sub i/ and a nitrogen source and was inhibited by the protein synthesis inhibitor cycloheximide. Exogenously added 14CO2 was not incorporated into oxalate, but was incorporated into acetate and malate, thus indicating the biosynthesis of oxalate by hydrolytic cleavage of oxaloacetate. Inhibition of mitochondrial citrate metabolism by fluorocitrate did not significantly decrease the oxalate yield. The putative enzyme that was responsible for this oxaloacetate hydrolase (EC 3.7.1.1), which was induced de novo during the pH shift. Subcellular fractionation of oxalic acid-forming mycelia of A. niger showed that this enzyme is located in the cytoplasm of A. niger. The results are consistent with a cytoplasmic pathway of oxalate formation which does not involve the tricarboxylic acid cycle

  19. Optimization of cassava root sieviate medium to an enriched animal feed by Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Mbah G.O

    2016-07-01

    Full Text Available - Optimization of the media components cassava root sieviate with Aspergellus Niger was carried out using Face-Centered Central Composite Design (FCCCD of the Response Surface Methodology (RSM and the responses were measured in terms of protein and crude fiber contents. Statistical Analysis (ANOVA of the result showed that time and substrate concentration had effect on biodegraded cassava root sieviate (p-value was 0.00 ie. 0.00 < 0.05. The optimum value of enriched cassava root sieviate with Aspergellus Niger were found to be on 10 days (time and 6g/10ml concentration resulting to 9.42% from 1.85% enrichment in protein content and degrading crude fiber to 8.38%, from 70.3%, thus indicating the potency of Aspergillus niger for the production of economical livestock feed from renewable source.

  20. Biocatalytic potential of laccase-like multicopper oxidases from Aspergillus niger

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    Tamayo-Ramos Juan Antonio

    2012-12-01

    Full Text Available Abstract Background Laccase-like multicopper oxidases have been reported in several Aspergillus species but they remain uncharacterized. The biocatalytic potential of the Aspergillus niger fungal pigment multicopper oxidases McoA and McoB and ascomycete laccase McoG was investigated. Results The laccase-like multicopper oxidases McoA, McoB and McoG from the commonly used cell factory Aspergillus niger were homologously expressed, purified and analyzed for their biocatalytic potential. All three recombinant enzymes were monomers with apparent molecular masses ranging from 80 to 110 kDa. McoA and McoG resulted to be blue, whereas McoB was yellow. The newly obtained oxidases displayed strongly different activities towards aromatic compounds and synthetic dyes. McoB exhibited high catalytic efficiency with N,N-dimethyl-p-phenylenediamine (DMPPDA and 2,2-azino-di(3-ethylbenzthiazoline sulfonic acid (ABTS, and appeared to be a promising biocatalyst. Besides oxidizing a variety of phenolic compounds, McoB catalyzed successfully the decolorization and detoxification of the widely used textile dye malachite green. Conclusions The A. niger McoA, McoB, and McoG enzymes showed clearly different catalytic properties. Yellow McoB showed broad substrate specificity, catalyzing the oxidation of several phenolic compounds commonly present in different industrial effluents. It also harbored high decolorization and detoxification activity with the synthetic dye malachite green, showing to have an interesting potential as a new industrial biocatalyst.

  1. Mechanism for mercury tolerance in fungi. [Aspergillus niger; Rhizoctonia solani; Pythium ultimum

    Energy Technology Data Exchange (ETDEWEB)

    Ashworth, L.J. Jr.; Amin, J.V.

    1964-01-01

    Aspergillus niger was protected from mercury (Hg) poisoning by sulfhydryl (SH) compounds (glutathione and cysteine) in culture experiments, whereas Rhizoctonia solani and Pythium ultimum were not protected. Two- to 30-day-old mycelium of A. niger was found to be more tolerant to Hg than either younger or older mycelia. Mycelia of the other fungi were sensitive regardless of age. Mercury tolerance of A. niger mycelium was altered when sulfur nutrition was modified; it was greater after growth on a substrate containing reduced sulfur than after growth on one containing sulfate. The Hg tolerance of A. niger mycelium appears to be due to a pool of intracellular SH that is free of protein and that protects enzyme systems by forming complexes with Hg as it is taken up by the thallus. Potato-dextrose broth-grown mats of A. niger contained about 100 ..mu..g of SH/g of dry mycelia after 36 hr and after 5 days. R.. solani had about 9 ..mu..g of SH/g of mycelia after 5 days; a measurable amount was not recovered from P. ultimum. 20 references, 1 figure, 2 tables.

  2. Enantioselective hydrolysis of epichlorohydrin using whole Aspergillus niger ZJB-09173 cells in organic solvents

    Indian Academy of Sciences (India)

    Huo-Xi Jin; Zhong-Ce Hu; Yu-Guo Zheng

    2012-09-01

    The enantioselective hydrolysis of racemic epichlorohydrin for the production of enantiopure ()-epichloro-hydrin using whole cells of Aspergillus niger ZJB-09173 in organic solvents was investigated. Cyclohexane was used as the reaction medium based on the excellent enantioselectivity of epoxide hydrolase from A. niger ZJB-09173 in cyclohexane. However, cyclohexane had a negative effect on the stability of epoxide hydrolase from A. niger ZJB-09173. In the cyclohexane medium, substrate inhibition, rather than product inhibition of catalysis, was observed in the hydrolysis of racemic epichlorohydrin using A. niger ZJB-09173. The racemic epichlorohydrin concentration was markedly increased by continuous feeding of substrate without significant decline of the yield. Ultimately, 18.5% of ()-epichlorohydrin with 98% enantiomeric excess from 153.6 mM of racemic epichlorohydrin was obtained by the dry cells of A. niger ZJB-09173, which was the highest substrate concentration in the production of enantiopure ()-epichlorohydrin by epoxide hydrolases using an organic solvent medium among the known reports.

  3. Evaluation of Antimicrobial Activity of Glucose Oxidase from Aspergillus niger EBL-A and Penicillium notatum

    Directory of Open Access Journals (Sweden)

    Muhammad Anjum Zia

    2013-12-01

    Full Text Available This work aimed to study the production and purification of glucose oxidase by Aspergillus niger and Penicillium notatum using corn steep liquor as the substrate and evaluate its antimicrobial activity for use in pharmaceutical and food industries. The enzyme was purified by ammonium sulfate precipitation (60-85%, DEAE-cellulose ion exchange and Sephadex G-200 size exclusion chromatography. The crude enzyme extracts of A. niger and P. notatum showed 2.32 and 5.53 U mg-1 specific activities, respectively, which after desalting was 15.52 and 12.05 U mg-1, and after ion exchange and gel filtration chromatography was 29.09 - 62 and 25.72 - 59.37 U mg-1 for A. niger and P. notatum, respectively. The antimicrobial activity was determined by disc diffusion method against selected microbial strains where glucose oxidase from A. niger showed anti-bacterial activity, while no fungicidal effects were shown by both A. niger and P. notatum glucose oxidases.

  4. Characteristics of exo- polygalacturonase produced by irradiated Aspergillus niger and Trichoderma viride spores

    International Nuclear Information System (INIS)

    Out of 69 fungal isolates from nine pectin rich fresh fruit wastes-showed pectinolytic activity, two were the powerful and best. They were identified as Aspergillus niger and Trichoderma viride. Gamma irradiation of the spore suspensions of these two isolates (0- 3 kGy) stimulated the exo-polygalacturonase (PG) production. Treatment with 0.25 kGy and 0.25-0.50 kGy was found to be the best doses for inducing PG activity produced from T. viride and Asp. niger respectively . The enzyme characteristics were also studied. The optimum temperature of T. viride enzyme reaction was 5 C compared with 45 degree C for Asp. niger enzyme extract.The optimum incubation time of T. viride enzyme reaction was 70-80 min which greater than that of Asp. niger namely 60 min.The results of enzyme reaction ph revealed that the best PG activity was observed at ph 5.0 for the extract of the two fungal isolates. The stability of the enzyme was affected markedly by each of incubation temp., incubation period and ph value .A. niger and T. viride crude extract enzymes were stimulated with Mn2+ while Zn2+ and Ca2+ were inhibitors. The best volume of crude enzyme extract was 3.00 ml in case of T. viride while in case of A. niger was 2.00 ml. T. viride enzyme extract showed its highest enzyme activity with substrate concentration 1.5 % while that of A. niger was found to be 3.0%.

  5. Physicochemical Properties Analysis and Secretome of Aspergillus niger in Fermented Rapeseed Meal.

    Science.gov (United States)

    Shi, Changyou; He, Jun; Yu, Jie; Yu, Bing; Mao, Xiangbing; Zheng, Ping; Huang, Zhiqing; Chen, Daiwen

    2016-01-01

    The nutrient digestibility and feeding value of rapeseed meal (RSM) for non-ruminant animals is poor due to the presence of anti-nutritional substances such as glucosinolate, phytic acid, crude fiber etc. In the present study, a solid state fermentation (SSF) using Aspergillus niger was carried out with the purpose of improving the nutritional quality of RSM. The chemical composition and physicochemical properties of RSM before and after fermentation were compared. To further understand possible mechanism of solid state fermentation, the composition of extracellular enzymes secreted by Aspergillus niger during fermentation was analysed using two-dimentional difference gel electrophoresis (2D-DIGE) combined with matrix assisted laser desorption ionization-time of flight-mass spectrometer (MALDI-TOF-MS). Results of the present study indicated that SSF had significant effects on chemical composition of RSM. The fermented rapeseed meal (FRSM) contained more crude protein (CP) and amino acid (AA) (except His) than unfermented RSM. Notably, the small peptide in FRSM was 2.26 time larger than that in unfermented RSM. Concentrations of anti-nutritional substrates in FRSM including neutral detergent fiber (NDF), glucosinolates, isothiocyanate, oxazolidithione, and phytic acid declined (P < 0.05) by 13.47, 43.07, 55.64, 44.68 and 86.09%, respectively, compared with unfermented RSM. A. niger fermentation disrupted the surface structure, changed macromolecular organic compounds, and reduced the protein molecular weights of RSM substrate. Total proteins of raw RSM and FRSM were separated and 51 protein spots were selected for mass spectrometry according to 2D-DIGE map. In identified proteins, there were 15 extracellular hydrolases secreted by A. niger including glucoamylase, acid protease, beta-glucanase, arabinofuranosidase, xylanase, and phytase. Some antioxidant related enzymes also were identified. These findings suggested that A. niger is able to secrete many extracellular

  6. Mutualistic interaction between Salmonella enterica and Aspergillus niger and its effects on Zea mays colonization.

    Science.gov (United States)

    Balbontín, Roberto; Vlamakis, Hera; Kolter, Roberto

    2014-11-01

    Salmonella Typhimurium inhabits a variety of environments and is able to infect a broad range of hosts. Throughout its life cycle, some hosts can act as intermediates in the path to the infection of others. Aspergillus niger is a ubiquitous fungus that can often be found in soil or associated to plants and microbial consortia. Recently, S. Typhimurium was shown to establish biofilms on the hyphae of A. niger. In this work, we have found that this interaction is stable for weeks without a noticeable negative effect on either organism. Indeed, bacterial growth is promoted upon the establishment of the interaction. Moreover, bacterial biofilms protect the fungus from external insults such as the effects of the anti-fungal agent cycloheximide. Thus, the Salmonella-Aspergillus interaction can be defined as mutualistic. A tripartite gnotobiotic system involving the bacterium, the fungus and a plant revealed that co-colonization has a greater negative effect on plant growth than colonization by either organism in dividually. Strikingly, co-colonization also causes a reduction in plant invasion by S. Typhimurium. This work demonstrates that S. Typhimurium and A. niger establish a mutualistic interaction that alters bacterial colonization of plants and affects plant physiology. PMID:25351041

  7. Aspergillus Niger reduces skeletal muscle protein breakdown and stimulates growth in broilers

    Directory of Open Access Journals (Sweden)

    Ahmed. A. Saleh

    2011-04-01

    Full Text Available This study was conducted to show that the inclusion of a fungus, Aspergillus Niger, as a dietary supplement in feed reduces protein breakdown in skeletal muscle and stimulates growth in broiler chickens. A total of 24 chicks at 15 d of age were divided into a control group and 3 treatment groups (6 birds per treatment. The control group was fed a basic diet, and the 3 treatment groups were fed the basic diet supplemented with A. Niger at a concentration of 0.01, 0.05 and 0.1% respectively. The birds were raised for 12 d from 15 d of age and were evaluated for the fungi’s effects on growth, organ weight and plasma 3-methylhistidine concentration as an index of skeletal muscle protein breakdown The mRNAs of atrogin-1, ubiquitin, proteasome and m-calpain were also measured to identify the mechanism underlying the decrement of the muscle protein breakdown resulting from Aspergillus. Body weight gain and breast muscle weight were increased even though feed intake by the chicks was decreased by the presence of the fungus, thus improving feed efficiency. Furthermore, plasma 3-methylhistidine concentration was decreased by the fungus. The mRNAs of atrogin-1, ubiquitin, proteasome and m-calpain were decreased, supporting the conclusion that the fungus decreases skeletal muscle protein breakdown. In conclusion, feeding A. Niger improves growth performance because proteolytic activity in skeletal muscle is reduced.

  8. Optimization of ellagitannase production by Aspergillus niger GH1 by solid-state fermentation.

    Science.gov (United States)

    de la Cruz, Reynaldo; Ascacio, Juan A; Buenrostro, Juan; Sepúlveda, Leonardo; Rodríguez, Raúl; Prado-Barragán, Arely; Contreras, Juan C; Aguilera, Antonio; Aguilar, Cristóbal N

    2015-01-01

    Ellagic acid is one of the most bioactive antioxidants with important applications in pharmaceutical, cosmetic, and food industries. However, there are few biotechnological processes developed for its production, because it requires precursors (ellagitannins) and the corresponding biocatalyst (ellagitannase). The aim of this study was to optimize the culture conditions for ellagitannase production by Aspergillus niger in solid-state fermentation (SSF). The bioprocess was carried out into a column bioreactor packed with polyurethane foam impregnated with an ellagitannins solution as carbon source. Four strains of Aspergillus niger (PSH, GH1, HT4, and HC2) were evaluated for ellagitannase production. The study was performed in two experimental steps. A Plackett-Burman design was used to determine the influencing parameters on ellagitannase production. Ellagitannins concentration, KCl, and MgSO4 were determined to be the most significant parameters. Box-Behnken design was used to define the interaction of the selected parameters. The highest enzyme value was obtained by A. niger PSH at concentrations of 7.5 g/L ellagitannins, 3.04 g/L KCl, and 0.76 g/L MgSO4. The methodology followed here allowed increasing the ellagitannase activity 10 times over other researcher results (938.8 U/g ellagitannins). These results are significantly higher than those reported previously and represent an important contribution for the establishment of a new bioprocess for ellagic acid and ellagitannase production. PMID:25085574

  9. Comparative Secretome Analysis of Aspergillus niger, Trichoderma reesei, and Penicillium oxalicum During Solid-State Fermentation.

    Science.gov (United States)

    Gong, Weili; Zhang, Huaiqiang; Liu, Shijia; Zhang, Lili; Gao, Peiji; Chen, Guanjun; Wang, Lushan

    2015-11-01

    Filamentous fungi such as Aspergillus spp., Trichoderma spp., and Penicillium spp. are frequently used to produce high concentrations of lignocellulosic enzymes. This study examined the discrepancies in the compositions and dynamic changes in the extracellular enzyme systems secreted by Aspergillus niger ATCC1015, Trichoderma reesei QM9414, and Penicillium oxalicum 114-2 cultured on corn stover and wheat bran. The results revealed different types and an abundance of monosaccharides and oligosaccharides were released during incubation, which induced the secretion of diverse glycoside hydrolases. Both the enzyme activities and isozyme numbers of the three fungal strains increased with time. A total of 279, 161, and 183 secretory proteins were detected in A. niger, T. reesei, and P. oxalicum secretomes, respectively. In the A. niger secretomes, more enzymes involved in the degradation of (galacto)mannan, xyloglucan, and the backbone of pectin distributed mostly in dicots were detected. In comparison, although P. oxalicum 114-2 hardly secreted any xyloglucanases, the diversities of enzymes involved in the degradation of xylan and β-(1,3;1,4)-D-glucan commonly found in monocots were higher. The cellulase system of P. oxalicum 114-2 was more balanced. The degradation preference provided a new perspective regarding the recomposition of lignocellulosic enzymes based on substrate types. PMID:26319683

  10. Adsorção de índigo carmim em biomassas mortas de aspergillus niger Adsorption of indigo carmine on dead biomass of aspergillus niger

    Directory of Open Access Journals (Sweden)

    Karina Oliveira Chaves

    2008-12-01

    Full Text Available As indústrias têxteis geram efluentes ricos em corantes durante toda a sua cadeia produtiva. Neste estudo, ensaios cinéticos foram realizados utilizando biomassas mortas de Aspergillus niger, diferentemente tratadas, como adsorvente para a remoção de índigo carmim a partir de soluções aquosas. Ensaio cinético com carvão ativado comercial também foi realizado para comparação. Os resultados obtidos indicam que a biomassa fúngica sem tratamento algum foi capaz de remover 95% do índigo carmim da solução aquosa, remoção equivalente àquela obtida pelo carvão ativado comercial. Os experimentos mostraram que os tratamentos ácidos melhoraram consideravelmente a cinética da remoção do corante, não influenciando, contudo, a capacidade adsortiva máxima do material. Os tratamentos salinos e alcalinos diminuíram tanto a capacidade máxima quanto a cinética de adsorção.Textile industries produce effluents rich in dyes throughout its production chain. In this study, kinetic experiments were carried using the dead and treated biomass of Aspergillus niger for indigo carmine removal from the synthetic aqueous solutions of this dye. A kinetic run with activated carbon was also carried for comparison. The obtained results suggest that non-treated fungal biomass has been capable of remove 95% of carmine indigo from the aqueous solutions. This removal was similar to that obtained with activated carbon. The results also indicate that acid treatments considerably improve the kinetic of the dye removal, but they are not influenced the maximum adsorptive capacity of the adsorbent. Moreover, saline and alkaline treatments decreased both the maximum capacity and the kinetic of adsorption.

  11. Biological leaching of heavy metals from a contaminated soil by Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Ren Wanxia, E-mail: ren_laura@163.com [Institute of Applied Ecology, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016 (China); Li Peijun, E-mail: lipeijun@iae.ac.cn [Institute of Applied Ecology, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016 (China); Geng Yong; Li Xiaojun [Institute of Applied Ecology, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016 (China)

    2009-08-15

    Bioleaching of heavy metals from a contaminated soil in an industrial area using metabolites, mainly weak organic acids, produced by a fungus Aspergillus niger was investigated. Batch experiments were performed to compare the leaching efficiencies of one-step and two-step processes and to determine the transformation of heavy metal chemical forms during the bioleaching process. After the one or two-step processes, the metal removals were compared using analysis of variance (ANOVA) and least-significance difference (LSD). A. niger exhibits a good potential in generating a variety of organic acids effective for metal solubilisation. Results showed that after the one-step process, maximum removals of 56%, 100%, 30% and 19% were achieved for copper, cadmium, lead and zinc, respectively. After the two-step process, highest removals of 97.5% Cu, 88.2% Cd, 26% Pb, and 14.5% Zn were obtained. Results of sequential extraction showed that organic acids produced by A. niger were effective in removing the exchangeable, carbonate, and Fe/Mn oxide fractions of Cu, Cd, Pb and Zn; and after both processes the metals remaining in the soil were mainly bound in stable fractions. Such a treatment procedure indicated that leaching of heavy metals from contaminated soil using A. niger has the potential for use in remediation of contaminated soils.

  12. Biological leaching of heavy metals from a contaminated soil by Aspergillus niger

    International Nuclear Information System (INIS)

    Bioleaching of heavy metals from a contaminated soil in an industrial area using metabolites, mainly weak organic acids, produced by a fungus Aspergillus niger was investigated. Batch experiments were performed to compare the leaching efficiencies of one-step and two-step processes and to determine the transformation of heavy metal chemical forms during the bioleaching process. After the one or two-step processes, the metal removals were compared using analysis of variance (ANOVA) and least-significance difference (LSD). A. niger exhibits a good potential in generating a variety of organic acids effective for metal solubilisation. Results showed that after the one-step process, maximum removals of 56%, 100%, 30% and 19% were achieved for copper, cadmium, lead and zinc, respectively. After the two-step process, highest removals of 97.5% Cu, 88.2% Cd, 26% Pb, and 14.5% Zn were obtained. Results of sequential extraction showed that organic acids produced by A. niger were effective in removing the exchangeable, carbonate, and Fe/Mn oxide fractions of Cu, Cd, Pb and Zn; and after both processes the metals remaining in the soil were mainly bound in stable fractions. Such a treatment procedure indicated that leaching of heavy metals from contaminated soil using A. niger has the potential for use in remediation of contaminated soils.

  13. Salmonella biofilm formation on Aspergillus niger involves cellulose--chitin interactions.

    Science.gov (United States)

    Brandl, Maria T; Carter, Michelle Q; Parker, Craig T; Chapman, Matthew R; Huynh, Steven; Zhou, Yaguang

    2011-01-01

    Salmonella cycles between host and nonhost environments, where it can become an active member of complex microbial communities. The role of fungi in the environmental adaptation of enteric pathogens remains relatively unexplored. We have discovered that S. enterica Typhimurium rapidly attaches to and forms biofilms on the hyphae of the common fungus, Aspergillus niger. Several Salmonella enterica serovars displayed a similar interaction, whereas other bacterial species were unable to bind to the fungus. Bacterial attachment to chitin, a major constituent of fungal cell walls, mirrored this specificity. Pre-incubation of S. Typhimurium with N-acetylglucosamine, the monomeric component of chitin, reduced binding to chitin beads by as much as 727-fold and inhibited attachment to A. niger hyphae considerably. A cellulose-deficient mutant of S. Typhimurium failed to attach to chitin beads and to the fungus. Complementation of this mutant with the cellulose operon restored binding to chitin beads to 79% of that of the parental strain and allowed for attachment and biofilm formation on A. niger, indicating that cellulose is involved in bacterial attachment to the fungus via the chitin component of its cell wall. In contrast to cellulose, S. Typhimurium curli fimbriae were not required for attachment and biofilm development on the hyphae but were critical for its stability. Our results suggest that cellulose-chitin interactions are required for the production of mixed Salmonella-A. niger biofilms, and support the hypothesis that encounters with chitinaceous alternate hosts may contribute to the ecological success of human pathogens. PMID:22003399

  14. EFFECT OF SOME ECOLOGICAL FACTORS ON THEGROWTH OF ASPERGILLUS NIGER AND CLADOSPORIUM SPHAEROSPERMUM

    Directory of Open Access Journals (Sweden)

    Ibtisam Mohammed Ababutain

    2013-01-01

    Full Text Available Indoor airborne fungi have been implicated in human health problems, damage to building materials, books, clothes and stored foods, which effected by different ecological factors. Aspergillus niger and Cladosporium sphaerospermum are the most dominant indoor airborne fungi were obtained from our previous study. The effect of normal indoor conditions (Temperature and Relative Humidity on their growth was studied. Including their nutrients growth requirements. The PDA medium was the appropriate growth medium for Cl. sphaerospermum, with a significant difference at (pA. niger, with no significant difference. The temperatures 25 and 30°C favored colony diameter growth for Cl. sphaerospermum and A. niger, respectively with a significant difference at (pCl. sphaerospermum increased to reach its maximum at 100% RH. Whereas, A. niger prefers to grow at lower RH comparing to Cl. sphaerospermum to reach its maximum at 75% RH with a significant difference at (pCl. sphaerospermum can be used as indicator fungi for the high humidity level in residences. The result has proved that keeping the humidity low enough can prevent fungi growth.

  15. Salmonella biofilm formation on Aspergillus niger involves cellulose--chitin interactions.

    Directory of Open Access Journals (Sweden)

    Maria T Brandl

    Full Text Available Salmonella cycles between host and nonhost environments, where it can become an active member of complex microbial communities. The role of fungi in the environmental adaptation of enteric pathogens remains relatively unexplored. We have discovered that S. enterica Typhimurium rapidly attaches to and forms biofilms on the hyphae of the common fungus, Aspergillus niger. Several Salmonella enterica serovars displayed a similar interaction, whereas other bacterial species were unable to bind to the fungus. Bacterial attachment to chitin, a major constituent of fungal cell walls, mirrored this specificity. Pre-incubation of S. Typhimurium with N-acetylglucosamine, the monomeric component of chitin, reduced binding to chitin beads by as much as 727-fold and inhibited attachment to A. niger hyphae considerably. A cellulose-deficient mutant of S. Typhimurium failed to attach to chitin beads and to the fungus. Complementation of this mutant with the cellulose operon restored binding to chitin beads to 79% of that of the parental strain and allowed for attachment and biofilm formation on A. niger, indicating that cellulose is involved in bacterial attachment to the fungus via the chitin component of its cell wall. In contrast to cellulose, S. Typhimurium curli fimbriae were not required for attachment and biofilm development on the hyphae but were critical for its stability. Our results suggest that cellulose-chitin interactions are required for the production of mixed Salmonella-A. niger biofilms, and support the hypothesis that encounters with chitinaceous alternate hosts may contribute to the ecological success of human pathogens.

  16. An antifungal role of hydrogen sulfide on the postharvest pathogens Aspergillus niger and Penicillium italicum.

    Directory of Open Access Journals (Sweden)

    Liu-Hui Fu

    Full Text Available In this research, the antifungal role of hydrogen sulfide (H2S on the postharvest pathogens Aspergillus niger and Penicillium italicum growing on fruits and under culture conditions on defined media was investigated. Our results show that H2S, released by sodium hydrosulfide (NaHS effectively reduced the postharvest decay of fruits induced by A. niger and P. italicum. Furthermore, H2S inhibited spore germination, germ tube elongation, mycelial growth, and produced abnormal mycelial contractions when the fungi were grown on defined media in Petri plates. Further studies showed that H2S could cause an increase in intracellular reactive oxygen species (ROS in A. niger. In accordance with this observation we show that enzyme activities and the expression of superoxide dismutase (SOD and catalase (CAT genes in A. niger treated with H2S were lower than those in control. Moreover, H2S also significantly inhibited the growth of Saccharomyces cerevisiae, Rhizopus oryzae, the human pathogen Candida albicans, and several food-borne bacteria. We also found that short time exposure of H2S showed a microbicidal role rather than just inhibiting the growth of microbes. Taken together, this study suggests the potential value of H2S in reducing postharvest loss and food spoilage caused by microbe propagation.

  17. Removal of iron impurities from kaolin obtained Reza-Abad mine using Aspergillus niger

    Directory of Open Access Journals (Sweden)

    M. Pazouki

    2010-01-01

    Full Text Available Kaolin known as mineral clay possesses special feature has extensive industrial usage. One of the distinct criteria of this substance is its white color. There are extensive resources of kaolin in Iran which unfortunately, due to the existence of iron oxides does not have transparent properties. In this study biological dissolution of iron oxide by Aspergillus niger NCIM548 was conducted in order to remove kaolin impurities. As a result, a model was developed to predict the percentage of iron removal using A. niger. Bioleaching of iron oxide at optimum condition resulted 2.2 percent of total iron removal. The obtained results were promising for continuous process. There was possibility of increasing iron oxide removal at optimum operating condition with use of related fungi. Further studies may be required to enhance the desired condition for maximum iron oxide removal from kaolin.

  18. Systemic analysis of the response of Aspergillus niger to ambient pH

    DEFF Research Database (Denmark)

    Andersen, Mikael Rørdam; Lehmann, Linda Olkjær; Nielsen, Jens

    2009-01-01

    highly efficient acidification as well as production process applicable knowledge on the transcriptional regulation of pH response in the industrially important A. niger. It has also made clear that filamentous fungi have evolved to employ several offensive strategies for out-competing rival organisms.......Background: The filamentous fungus Aspergillus niger is an exceptionally efficient producer of organic acids, which is one of the reasons for its relevance to industrial processes and commercial importance. While it is known that the mechanisms regulating this production are tied to the levels of...... ambient pH, the reasons and mechanisms for this are poorly understood. Methods: To cast light on the connection between extracellular pH and acid production, we integrate results from two genome-based strategies: A novel method of genome-scale modeling of the response, and transcriptome analysis across...

  19. Efficient Conversion of Inulin to Inulooligosaccharides through Endoinulinase from Aspergillus niger.

    Science.gov (United States)

    Xu, Yanbing; Zheng, Zhaojuan; Xu, Qianqian; Yong, Qiang; Ouyang, Jia

    2016-03-30

    Inulooligosaccharides (IOS) represent an important class of oligosaccharides at industrial scale. An efficient conversion of inulin to IOS through endoinulinase from Aspergillus niger is presented. A 1482 bp codon optimized gene fragment encoding endoinulinase from A. niger DSM 2466 was cloned into pPIC9K vector and was transformed into Pichia pastoris KM71. Maximum activity of the recombinant endoinulinase, 858 U/mL, was obtained at 120 h of the high cell density fermentation process. The optimal conditions for inulin hydrolysis using the recombinant endoinulinase were investigated. IOS were harvested with a high concentration of 365.1 g/L and high yield up to 91.3%. IOS with different degrees of polymerization (DP, mainly DP 3-6) were distributed in the final reaction products. PMID:26961750

  20. Biotransformation of the streptomyces scabies phytotoxin thaxtomin A by the fungus aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Lazarovits, G.; Hill, J. [Agriculture and Agri-Food Canada, Southern Crop Protection and Food Research Centre, London, Ontario (Canada)]. E-mail: Lazarovitsg@agr.gc.ca; King, R. [Agriculture and Agri-Food Canada, Potato Research Centre, Fredericton, New Brunswick (Canada); Calhoun, L.A. [Univ. of New Brunswick, Dept. of Chemistry, Fredericton, New Brunswick (Canada)

    2004-07-01

    Of several hundred microorganisms randomly selected from the environment, only a fungal isolate identified as Aspergillus niger van Tiegham var. niger was found to transform the phytotoxin thaxtomin A to much less toxic metabolites. The rate and extent of transformation of thaxtomin A was tested under a variety of conditions, including different growth media, biomass concentrations, incubation periods, and shaker speeds. Under optimum conditions the fungus converted thaxtomin A into two major and five minor metabolites. The two major metabolites and three of the five minor metabolites were fully characterized by a combination of mass spectral and nuclear magnetic resonance techniques. When assayed on aseptically produced mini-tubers, the major metabolites proved to be much less phytotoxic than thaxtomin A. (author)

  1. Isolation and genetic analysis of Aspergillus niger mutants with reduced extracellular glucoamylase

    International Nuclear Information System (INIS)

    Mutants with impaired production of extracellular glucoamylase were isolated at a high frequency (2% of survivors) from an Aspergillus niger strain treated with UV light. These were designated as low glucoamylase producers (lgp, up to 30% of the parental yield) and medium producers (mgp, a 35 to 50% decrease in enzyme level). All the mutants were shown to be recessive; one strain segregated two unlinked genes. Complementation tests, and segregation from heterozygous diploid, suggested at least three to four unlinked genes, each able to impair glucoamylase production. There is evidence of a single structural gene for glucoamylase in A. niger. Therefore, as production of extracellular enzymes is normally the final result of several steps at intracellular and membrane levels, including regulation of enzyme synthesis, we suggest intergenic interaction that controls extracellular enzyme accumulation and that mutation in any of these genes would result in impaired production. (author)

  2. The effects of different carbon sources on biosynthesis of pectinolytic enzymes by Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Kiro Mojsov

    2010-11-01

    Full Text Available The aim of this work was to investigate the effects of different carbon sources on the nourishing base on the production of pectinolytic enzymes by Aspergillus niger with the aim of optimizing the medium for maximal enzyme production. Growth and enzymes production by Aspergillus niger were evaluated on glucose, fructose, galactose, xylose, lactose, apple pectin and the dry apple pulp. Results of different carbon sources on base showed maximal endo-pectinolytic activity, endo-PG/328 U L-1 with the pressed apple pulp, compared with endo-PG/140 U L-1 with apple pectin, endo-PG/62 U L-1 with galactose, endo-PG/28 U L-1 with lactose, endo-PG/0.0 U L-1 with glucose and fructose and endo-PG/5.0 U L-1 without carbon source (control. The growth of the microorganism (dry biomass on different carbon sources showed maximum dry biomass, 4.5 g L-1 with glucose, compared with dry biomass, 4.3 g L-1 with fructose, 4.0 g L-1 with the pressed apple pulp, 3.5 g L-1 with galactose, 3.0 g L-1 with lactose, 2.2 g L-1 with apple pectin and 0.8 g L-1 without carbon source (control. Maximal endo-PG production, 328 U L-1 and dry biomass, 4.0 g L-1 by fungus Aspergillus niger was observed in a medium at pH initial, 4.0. The results presented here will be of commercial importance for using apple pulp as a carbon source for production of pectinolytic enzymes in submerged fermentation.

  3. Production of Citric Acid from a New Substrate, Undersized Semolina, by Aspergillus niger

    OpenAIRE

    Alben, Emine; Erkmen, Osman

    2004-01-01

    The production of citric acid from fermentation medium (mass per volume ratio 0.01 % of undersized semolina) by Aspergillus niger was studied by shake culture method. The effects of initial pH (4.5, 5.5 and 6.5), methanol (volume fraction 1.0, 2.0 and 3.0 %) and ammonium nitrate (mass per volume ratio 0.01 %) on the production of citric acid were investigated. Citric acid concentration, biomass concentration and the amount of total carbohydrates (as glucose) were determined during fermentatio...

  4. Biotransformación de a-PINENO empleando Aspergillus niger

    OpenAIRE

    Fabián E. Castellanos; Aidé Perea Villamil; Claudia Ortíz López

    2007-01-01

    El a-pineno es uno de los monoterpenos más abundantes encontrado en aceites de coníferas y presente en la gran mayoría de aceites esenciales. Los pinenos son de gran valor como precursores de aromas y fragancias cuyos derivados se producen por oxidación y en menor cantidad por extracción directa de plantas. En este estudio se evaluó la biotransformación del a-pineno empleando Aspergillus niger como biocatalizador, en diferentes medios de reacción. Fue posible la obtención de...

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

  8. Optimization of solid state fermentation of sugar cane by Aspergillus niger considering particles size effect

    Energy Technology Data Exchange (ETDEWEB)

    Echevarria, J.; Rodriguez, L.J.A.; Delgado, G. (Instituto Cubano de Investigaciones de los Derivados de la Cana de Azucar (ICIDCA), La Habana (Cuba)); Espinosa, M.E. (Centro Nacional de Investigaciones Cientificas, La Habana (Cuba))

    1991-01-01

    The protein enrichment of sugar cane by solid state fermentation employing Aspergillus niger was optimized in a packed bed column using a two Factor Central Composit Design {alpha} = 2, considering as independent factors the particle diameter corresponding to different times of grinding for a sample and the air flow rate. It was significative for the air flow rate (optimum 4.34 VKgM) and the particle diameter (optimum 0.136 cm). The average particle size distribution, shape factor, specific surface, volume-surface mean diameter, number of particles, real and apparent density and holloweness for the different times of grinding were determined, in order to characterize the samples. (orig.).

  9. Low-cost carbon sources for the production of a thermostable xylanase by Aspergillus niger

    OpenAIRE

    Ana Cláudia Elias Pião Benedetti; Eliana Dantas da Costa; Caio Casale Aragon; Andréa Francisco dos Santos; Antônio José Goulart; Derlene Attili-Angelis; Rubens Monti

    2013-01-01

    A strain of the filamentous fungus Aspergillus niger was isolated and shown to possess extracellular xylanolytic activity. These enzymes have biotechnological potential and can be employed in various industries. This fungus produced its highest xylanase activity in a medium made up of 0.1% CaCO3 , 0.5% NaCl, 0.1% NH4 Cl, 0.5% corn steep liquor and 1% carbon source, at pH 8.0. A lowcost hemicellulose residue (powdered corncob) proved to be an excellent inducer of the A. ni...

  10. Dephosphorylation of Phytate by Using the Aspergillus niger Phytase with a High Affinity for Phytate

    OpenAIRE

    Nagashima, Tadashi; Tange, Tatsuya; Anazawa, Hideharu

    1999-01-01

    A phytase (EC 3.1.3.8) with a high affinity for phytic acid was found in Aspergillus niger SK-57 and purified to homogeneity in four steps by using ion-exchange chromatography (two types), gel filtration, and chromatofocusing. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the purified enzyme gave a single stained band at a molecular mass of approximately 60 kDa. The Michaelis constant of the enzyme for phytic acid (18.7 ± 4.6 μM) was statistically analyzed. In regard to the ort...

  11. A new naphthoquinoneimine derivative from the marine algal-derived endophytic fungus Aspergillus niger EN-13

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Cultivation of an endophytic fungus Aspergillus niger EN-13 that was isolated from the inner tissue of the marine brown alga Colpomenia sinuosa resulted in the characterization of a new naphthoquinoneimine derivative, namely, 5,7-dihydroxy-2-[1-(4-methoxy-6-oxo-6H-pyran-2-yl)-2-phenylethylamino]-[ 1,4]naphthoquinone. The structure of the new compound was established on the basis of various NMR spectroscopic analyses including 2D NMR techniques, EI-MS, and HR-ESI-MS. This compound displayed moderate antifungal activity.

  12. Identification of Genes Associated with Morphology in Aspergillus Niger by Using Suppression Subtractive Hybridization

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Ziyu; Mao, Xingxue; Magnuson, Jon K.; Lasure, Linda L.

    2004-04-01

    The morphology of citric acid production strains of Aspergillus niger is sensitive to a variety of factors including the concentration of manganese (Mn2+). Upon increasing the Mn2+ concentration in A. niger (ATCC 11414) cultures to 14 ppb or higher, the morphology switches from pelleted to filamentous, accompanied by a rapid decline in citric acid production. Molecular mechanisms through which Mn2+ exerts effects on morphology and citric acid production in A. niger have not been well defined, but our use of suppression subtractive hybridization has identified 22 genes responsive to Mn2+. Fifteen genes were differentially expressed when A. niger was grown in media containing 1000 ppb Mn2+ (filamentous form) and seven genes in 10 ppb Mn2+ (pelleted form). Of the fifteen filamentous-associated genes, seven are novel and eight share 47-100% identity to genes from other organisms. Five of the pellet-associated genes are novel, and the other two genes encode a pepsin-type protease and polyubiquitin. All ten genes with deduced functions are either involved in amino acid metabolism/protein catabolism or cell regulatory processes. Northern-blot analysis showed that the transcripts of all 22 genes were rapidly enhanced or suppressed by Mn2+. Steady-state mRNA levels of six selected filamentous associated genes remained high during five days of culture in a filamentous state and low under pelleted growth conditions. The opposite behavior was observed for four selected pellet-associated genes. The full-length cDNA of the filamentous-associated clone, Brsa-25 was isolated. Antisense expression of Brsa-25 permitted pelleted growth and increased citrate production at higher concentrations of Mn2+ than could be tolerated by the parent strain. The results suggest the involvement of the newly isolated genes in regulation of A. niger morphology.

  13. Determination of adhesion between single Aspergillus niger spores in aqueous solutions using an atomic force microscope.

    Science.gov (United States)

    Wargenau, Andreas; Kwade, Arno

    2010-07-01

    The interaction force between single cells in contact is of high interest in various interdisciplinary fields of biotechnology, for instance, in cultivation or biofilm formation. A method for the determination of adhesion forces between two single Aspergillus niger spores in different aqueous solutions was established in this study. Adhesion force distributions were determined at three different sodium chloride concentrations and two different pH values using an atomic force microscope (AFM). It was pointed out that adhesion data can be described by log-normal density functions, of which corresponding parameters have been estimated. Using the knowledge of distribution shape, the influence of the environmental condition on the mean values of adhesion force could be studied quantitatively. The highest value of 0.95 nN was observed at pH 2.5 and an ionic strength of 0.5 mol L(-1). Decreasing the ionic strength to 0.05 mol L(-1) decreases the adhesion force mean for about 25%. Increasing the pH value to pH 5 at a sodium chloride concentration of 0.154 mol L(-1) entails a decrease of adhesion from 0.88 to 0.56 nN. These results qualitatively agree with the absolute value of the expected surface potential of Aspergillus niger spores, which is much higher at pH 5 and should take more effect at lower concentrations of counterions. PMID:20387816

  14. The effects of inorganic salts on biosynthesis of pectinolytic enzymes by Aspergillus Niger

    Directory of Open Access Journals (Sweden)

    Kiro Mojsov

    2010-02-01

    Full Text Available The paper examines effects of different inorganic salts in an apple pulp base on the production of pectinolytic enzymes with the aim of optimizing the medium for maximal enzyme production. The apple pulp combined with corn flour and simple mineral salts was used as a nourishing base in submerged production of pectinolytic enzymes by the fungus Aspergillus niger MK-15. The growth of the microorganism (dry weight on different sources of nitrogen showed maximum dry weight with (NH42HPO4. The growth of the microorganism (dry weight on different concentration of (NH42HPO4 (by 0.2% to 0.8% provided maximal dry weight with 0.7% (NH42HPO4. The different inorganic salts (sources of nitrogen on base stimulated the production of pectinolytic enzymes and enhanced by up to twofold the growth of Aspergillus niger in submerged fermentation. The best source of nitrogen on base was (NH42HPO4 with optimal concentration of 0.7%. The obtained results represent practical importance for using apple pulp as a carbon source for production of pectinolytic enzymes in submerged fermentation.

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

    International Nuclear Information System (INIS)

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

  16. Effect of oxygen transfer rate on the composition of the pectolytic enzyme complex of Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Zetelaki-Horvath, K.; Vas, K.

    1981-01-01

    Optimal agitation and aeration conditions (assuring O/sub 2/ transfer rates (OTR) of 12-179 mmol/L-h) were determined for pectin lyase (PL) synthesis of an Aspergillus niger strain. Components of the pectolytic enzyme complex were also investigated in order to determine whether their O/sub 2/ demand is identical with or different from that of pectin lyase. Should the latter be the case, a possibility would be given to produce enzyme complexes of different agitation and aeration conditions. The mycelium yield of Aspergillus niger was maximum at an OTR of 100 mmol/L-h. The yields of the various pectolytic enzymes reached maximum at different OTRs. PL production was highest (0.555 mumol/min-mL) at an OTR of 60 mmol/L-h. Endopolygalacturonase (PG) production has a maximum at OTR 49 mmol/L-h, with a 2nd peak at 100-135 mmol O2/L-h. Pectin esterase (PE) synthesis showed a maximum at an OTR of 12-14 mmol/L-h, while both apple juice clarifying and macerating activities gave 2 maximum at 14 and 60 mmol/L-h due to the optima of PE and endo-PG. Macerating activity showed a high value at OTR optimal for PL production as well.

  17. Influence of Gibberellic Acid on Enhancement Growth of Aspergillus Niger for Chitosan Production

    International Nuclear Information System (INIS)

    Chitosan is obtained by chemical conversion of chitin, which is a constituent of the exoskeleton of crustacean and insects. An alternative source of chitosan is the cell wall of fungi. The waste biomass of Aspergillus niger, following citric acid production, was used as a source for fungal chitosan extraction. In this research we study the effect of different production media, different concentrations of molass, the effect of addition of gibberellic acid at different concentrations (1-5 mg/l) on mycelial growth and chitosan production from Aspergillus niger. Studying the effect of different incubation time. The results showed that, the best production medium was molass salt medium (MSM) with molass concentration 50 g/l and incubation time 48h. Maximum enhancement was observed at 2 mg gibberellic acid. Gibberellic acid at high concentrations inhibit both growth and chitosan content. The produced fungal chitosan was characterized with deacetylation degree of 81.3%, a molecular weight of 24.2 kDa and their FT-IR spectra were compared with that of shrimp chitosan.

  18. Crystallization and preliminary X-ray crystallographic analysis of recombinant β-mannosidase from Aspergillus niger

    International Nuclear Information System (INIS)

    β-Mannosidase from Aspergillus niger was crystallized in the presence of d-mannose and the crystal diffracted to 2.41 Å resolution. The crystal belonged to the space group P1 with unit-cell parameters a= 62.37, b = 69.73, c = 69.90 Å, α = 108.20, β = 101.51, γ = 103.20°. β-Mannosidase (EC 3.2.1.25) is an important exoglycosidase specific for the hydrolysis of terminal β-linked mannoside in various oligomeric saccharide structures. β-Mannosidase from Aspergillus niger was expressed in Pichia pastoris and purified to clear homogeneity. β-Mannosidase was crystallized in the presence of d-mannose and the crystal diffracted to 2.41 Å resolution. The crystal belonged to space group P1, with unit-cell parameters a = 62.37, b = 69.73, c = 69.90 Å, α = 108.20, β = 101.51, γ = 103.20°. The parameters derived from the data collection indicate the presence of one molecule in the asymmetric unit

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

    International Nuclear Information System (INIS)

    In this study, strains of Aspergillus niger No.4 for hyper citric acid were irradiated to different doses by 80 MeV/u 12C6+ ion beams. Seven mutant strains showed marked citric acid over-production records and faster productivity than initial Aspergillus niger No.4 by shaking flash fermentation. The maximum product yield was 132.8 gL-1 (the H4002 strain) being a 8.8% increase to the initial strain. The scale-up experiment was carried out in a 100 L bioreactor. The mutant H4002 can accumulate 187gL-1 product yield of citric acid from starch liquefying supernatant. The productivity of citric acid was 2.75 g L-1 h-1. So, the mutant H4002 possesses rapid sugar katabolism for producing citric acid. Meanwhile, the pellet morphology kept compact and round during the whole submerged fermentation, which was suited to produce citric acid. The results indicate that mutant H4002 has potential ability to produce citric acid rapidly. (authors)

  20. Optimization of fresh palm oil mill effluent biodegradation with Aspergillus niger and Trichoderma virens

    Directory of Open Access Journals (Sweden)

    Jalaludin Noorbaizura

    2016-03-01

    Full Text Available In this work, response surface optimization strategy was employed to enhance the biodegradation process of fresh palm oil mill effluent (POME by Aspergillus niger and Trichoderma virens. A central composite design (CCD combined with response surface methodology (RSM were employed to study the effects of three independent variables: inoculum size (%, agitation rate (rpm and temperature (°C on the biodegradation processes and production of biosolids enriched with fungal biomass protein. The results achieved using A. niger were compared to those obtained using T. virens. The optimal conditions for the biodegradation processes in terms of total suspended solids (TSS, turbidity, chemical oxygen demand (COD, specific resistance to filtration (SRF and production of biosolids enriched with fungal biomass protein in fresh POME treated with A. niger and T. virens have been predicted by multiple response optimization and verified experimentally at 19% (v/v inoculum size, 100 rpm, 30.2°C and 5% (v/v inoculum size, 100 rpm, 33.3°C respectively. As disclosed by ANOVA and response surface plots, the effects of inoculum size and agitation rate on fresh POME treatment process by both fungal strains were significant.

  1. Physiological and Chemical Studies on the Bioconversion of Glycyrrhizin by Aspergillus niger NRRL595

    Directory of Open Access Journals (Sweden)

    El-Refai, A. M. H.

    2012-06-01

    Full Text Available Glycyrrhizin (GL, the well-known sweet saponin of licorice, has been used as a food-additive and as a medicine. Its aglycone, glycyrrhetic acid (GA showed antiinflamatory, antiulcer and antiviral properties. GA is now produced form GL by acid hydrolysis. However, it is difficult to obtain GA in a good yield by using this method, because many by-productsare also produced. Screening of different microorganisms (13 bacteria, 2 yeasts and 23 fungi for production of GA from GL revealed that Aspergillus niger NRRL 595 produced the highest yield of GA. The bioconversion of GL by A. niger NRRL 595 for 96 h, followed by isolation and purification of the transformation products led to the separation of two conversion products, namely: GA and 3-oxo-GA. Confirmation of the identity of these products was established by determination of their Rf values, m.p., and IR, UV, MS and NMR spectra. The conditions for cultivation of this fungus with the maximum hydrolytic activity for the maximum yield of GA were investigated. Based on the results, A. niger NRRL 595 was cultivated with a medium composed of 1.75 % GL, 0.5 % glucose, 0.8 % corn steep liquor at pH 6.5 at 32 °C for 96 h. The cultivation of fungal cells under the latter conditions afforded GA and 3-oxo-GA in a yield of 65 % and 22 %, respectively.

  2. Putative Aspergillus niger-induced oxalate nephrosis in sheep : clinical communication

    Directory of Open Access Journals (Sweden)

    C.J. Botha

    2009-05-01

    Full Text Available A sheep farmer provided a maize-based brewer's grain (mieliemaroek and bales of Eragrostis curvula hay to ewes and their lambs, kept on zero-grazing in pens. The 'mieliemaroek' was visibly mouldy. After 14 days in the feedlot, clinical signs, including generalised weakness, ataxia of the hind limbs, tremors and recumbency, were noticed. Six ewes died within a period of 7 days. A post mortem examination was performed on 1 ewe. The carcass appeared to be cachectic with mild effusions into the body cavities; mild lung congestion and pallor of the kidneys were observed. Microscopical evaluation revealed nephrosis and birefringent oxalate crystals in the renal tubules when viewed under polarised light. A provisional diagnosis of oxalate nephrosis with subsequent kidney failure was made. Amongst other fungi, Aspergillus niger was isolated from 'mieliemaroek' samples submitted for fungal culture and identification. As A. niger is known to synthesise oxalates, a qualitative screen to detect oxalic acid in the mieliemaroek and purified A. niger isolates was performed using high-performance liquid chromatography (HPLC. Oxalic acid was detected, which supported a diagnosis of soluble oxalate-induced nephropathy.

  3. Upgrading of naringinase production by gamma irradiated Aspergillus niger uilizing agro-industrial processing wastes

    International Nuclear Information System (INIS)

    Naringinase-producing microorganisms were isolated locally from some citrus fruits and soil using a culture enrichment technique, and they were tested for their enzyme producing ability in shake flask cultures. Among the tested microorganisms, aspergillus niger-AH3 proved to be the most potent active isolate which gave 92.1 UMl-1 of naringinase activity in fermentation medium. Optimization effects of various fermentation medium constituents of agro-industrial processing wastes as substrates for naringinase production were studied. Of substrates used, corn steep liquor, soya bean meal, jojoba seed meal and bitter orange seed powder were the best for naringinase production .Maximum enzyme titer (145.5 Uml-1) was obtained in the optimized fermentation medium supplemented with 0.5% CaCo3 after 120 h of incubation. The highly potent ten enhanced isolates which were selected after treatment with gamma irradiation, had significantly elevated titers of naringinase activity compared with the parental wild strain A. niger-AH3. Enhanced isolate A. niger-AH3. γ20 derived from 2.0 kGy treated groups is exhibiting the highest enzyme activity 1.5 folds higher than parental strain. This suggests that a process for efficient utilization of the agro-industrial processing wastes in economical production of naringinase in large quantities which would be suitable for debittering process in the citrus fruit juice industry

  4. Cyanide hydratase from Aspergillus niger K10: Overproduction in Escherichia coli, purification, characterization and use in continuous cyanide degradation

    Czech Academy of Sciences Publication Activity Database

    Rinágelová, Anna; Kaplan, Ondřej; Veselá, Alicja Barbara; Chmátal, Martin; Křenková, Alena; Plíhal, Ondřej; Pasquarelli, Fabrizia; Cantarella, M.; Martínková, Ludmila

    2014-01-01

    Roč. 49, č. 3 (2014), s. 445-450. ISSN 1359-5113 R&D Projects: GA ČR(CZ) GAP504/11/0394; GA TA ČR TA01021368 Institutional support: RVO:61388971 Keywords : Cyanide hydratase * Nitrilase * Aspergillus niger Subject RIV: CE - Biochemistry Impact factor: 2.516, year: 2014

  5. Stimulating action of continuous γ-irradiation with low dose-rates on the growth and development of Aspergillus niger

    International Nuclear Information System (INIS)

    Continuous γ-irradiation (1.6 - 4.1 rad/hr) of Aspergillus niger cultured in a mineral medium has been shown to stimulate markedly the growth of the culture and the production of organic acids. Optimum conditions for the stimulating effect have been found

  6. Two novel, putatively cell wall-associated and glycosylphosphatidylinositol-anchored alpha-glucanotransferase enzymes of aspergillus niger

    NARCIS (Netherlands)

    van der Kaaij, R. A.; Yuan, X.-L.; Franken, A.; Ram, A. F. J.; Punt, P. J.; Dijkhuizen, L.; Maarel, M.J.E.C. van der

    2007-01-01

    In the genome sequence of Aspergillus niger CBS 513.88, three genes were identified with high similarity to fungal alpha-amylases. The protein sequences derived from these genes were different in two ways from all described fungal alpha-amylases: they were predicted to be glycosylphosphatidyllinosit

  7. Two novel, putatively cell wall-associated and glycosylphosphatidylinositol-anchored α-glucanotransferase enzymes of Aspergillus niger

    NARCIS (Netherlands)

    Kaaij, R.M. van der; Yuan, X.L.; Franken, A.; Ram, A.F.J.; Punt, P.J.; Maarel, M.J.E.C. van der; Dijkhuizen, L.

    2007-01-01

    In the genome sequence of Aspergillus niger CBS 513.88, three genes were identified with high similarity to fungal α-amylases. The protein sequences derived from these genes were different in two ways from all described fungal α-amylases: they were predicted to be glycosylphosphatidylinositol anchor

  8. Selection and characterisation of a xylitol-derepressed Aspergillus niger mutant that is apparently impaired in xylitol transport

    NARCIS (Netherlands)

    Vondervoort, van de P.J.I.; Groot, de M.J.L.; Ruijter, G.J.G.; Visser, J.

    2006-01-01

    Aspergillus niger is known for its biotechnological applications, such as the use of xylanase enzyme for the degradation of hemicellulose. Depending on culture conditions, several polyols may also be accumulated, such as xylitol during D-xylose oxidation. Also during industrial fermentation of xylos

  9. Radiosensitization of Aspergillus niger and Penicillium chrysogenum using basil essential oil and ionizing radiation for food decontamination.

    Science.gov (United States)

    The Minimum Inhibitory Concentration (MIC) of basil oil, was determined for two pathogenic fungi of rice, Aspergillus niger and Penicillium chrysogenum. The antifungal activity of the basil oil in combination with ionising radiation was then investigated to determine if basil oil caused radiosensit...

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

    DEFF Research Database (Denmark)

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

    2011-01-01

    The filamentous fungus Aspergillus niger exhibits great diversity in its phenotype. It is found globally, both as marine and terrestrial strains, produces both organic acids and hydrolytic enzymes in high amounts, and some isolates exhibit pathogenicity. Although the genome of an industrial enzym...

  11. EFFECT OF INOCULUM SIZE ON SURVIVAL RATE OF CANDIDA-ALBICANS AND ASPERGILLUS-NIGER IN TOPICAL PREPARATIONS

    NARCIS (Netherlands)

    VANDOORNE, H; DEVRINGER, T

    1994-01-01

    The survival of Candida albicans and Aspergillus niger in O/W creams with different types and concentrations of parabens was studied. The survival was not only dependent on the type and concentration of the preservative, but also on the size of the inoculum. The results are relevant for future propo

  12. Decolorization and detoxification of Synozol red HF-6BN azo dye, by Aspergillus niger and Nigrospora sp

    Directory of Open Access Journals (Sweden)

    Sidra Ilyas

    2013-01-01

    Full Text Available In the present investigation the fungi, Aspergillus niger and Nigrospora sp. were employed for decolorization of Synazol red HF-6BN. Decolorization study showed that Aspergillus niger and Nigrospora sp. were able to decolorize 88% and 96% Synazol red 6BN, respectively, in 24 days. It was also studied that 86% and 90% Synazol red containing of dye effluent was decolorized by Aspergillus niger and Nigrospora sp. after 28 days of incubation at room temperature. A fungal-based protein with relative molecular mass of 70 kDa was partially purified and examined for enzymatic characteristics. The enzyme exhibited highest activity at temperature ranging from 40-50[degree sign]C and at pH=6.0. The enzyme activity was enhanced in the presence of metal cations. High performance liquid chromatography analysis confirmed that these fungal strains are capable to degrade Synazol red dye into metabolites. No zones of inhibition on agar plates and growth of Vigna radiata in the presence of dye extracted sample, indicated that the fungal degraded dye metabolites are nontoxic to beneficial micro-flora and plant growth. Aspergillus niger and Nigrospora sp. have promising potential in color removal from textile wastewater-containing azo dyes.

  13. Presence of epoxide hydrolase activity in Aspergillus niger: Hydrolysis of 6', 7'-epoxybergamottin to 6', 7'-dihydroxybergamottin

    Science.gov (United States)

    The 6', 7'-epoxybergamottin (EB) is one of major furanocoumarins in grapefruit. Previously, we have shown that Aspergillus niger has a capability of metabolizing EB into 6', 7'-dihydroxybergamottin (DHB), which is further metabolized to bergaptol and bergaptol-5-sulfate in vivo. In this study, we at...

  14. Tratamento de efluentes de refinaria de petróleo em reatores com Aspergillus niger Treatment of petroleum refinery wastewater by reactors inoculated with Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Sandra Tédde Santaella

    2009-03-01

    Full Text Available Neste trabalho, avaliou-se o efeito do tempo de detenção hidráulica (TDH no desempenho de três reatores aeróbios inoculados com Aspergillus niger AN400, usados para tratamento de efluentes de refinarias de petróleo. Cada reator foi operado com um tempo de detenção hidráulica diferente: 4, 8 e 12 horas, durante 152 dias. Eles possuíam leito fixo de espuma de poliuretano e o escoamento era ascendente e contínuo. Determinaram-se: pH, fenóis, demanda química de oxigênio (DQO, amônia, nitrito e nitrato, no afluente e efluentes dos reatores. O TDH de oito horas foi o melhor para remoção de DQOsolúvel e não houve diferença entre os TDHs para remoção de fenóis totais. No período estável não houve remoção de nitrato; no entanto ocorreu remoção de nitrito de aproximadamente 99%. Além disto, houve produção de amônia devido à amonificação a partir do nitrito presente no meio.This paper evaluated the effect of hydraulic retention time (HRT on the performance of three upflow aerobic reactors, with polyurethane foam as support material, inoculated with Aspergillus niger AN400, used for the treatment of petroleum refinery wastewater. Each reactor was operated with a different HRT: 4, 8 and 12 hours, during 152 days. The performance was evaluated based on pH; phenols; COD, nitrate and nitrite. The results show that for the COD removal, it is more reasonable to operate the reactor with HRT of eight hours. However, there was no difference among results of phenol removal efficiency of the different HRTs. During steady state condition, nitrite was removed in approximately 99%, but there was no reduction on the nitrate concentration. Ammonia was produced in all reactors, probably due to ammonification of nitrite.

  15. Exploiting proteomic data for genome annotation and gene model validation in Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Grigoriev Igor V

    2009-02-01

    Full Text Available Abstract Background Proteomic data is a potentially rich, but arguably unexploited, data source for genome annotation. Peptide identifications from tandem mass spectrometry provide prima facie evidence for gene predictions and can discriminate over a set of candidate gene models. Here we apply this to the recently sequenced Aspergillus niger fungal genome from the Joint Genome Institutes (JGI and another predicted protein set from another A.niger sequence. Tandem mass spectra (MS/MS were acquired from 1d gel electrophoresis bands and searched against all available gene models using Average Peptide Scoring (APS and reverse database searching to produce confident identifications at an acceptable false discovery rate (FDR. Results 405 identified peptide sequences were mapped to 214 different A.niger genomic loci to which 4093 predicted gene models clustered, 2872 of which contained the mapped peptides. Interestingly, 13 (6% of these loci either had no preferred predicted gene model or the genome annotators' chosen "best" model for that genomic locus was not found to be the most parsimonious match to the identified peptides. The peptides identified also boosted confidence in predicted gene structures spanning 54 introns from different gene models. Conclusion This work highlights the potential of integrating experimental proteomics data into genomic annotation pipelines much as expressed sequence tag (EST data has been. A comparison of the published genome from another strain of A.niger sequenced by DSM showed that a number of the gene models or proteins with proteomics evidence did not occur in both genomes, further highlighting the utility of the method.

  16. Interesterification of butter fat by partially purified extracellular lipases from Pseudomonas putida, Aspergillus niger and Rhizopus oryzae.

    Science.gov (United States)

    Pabai, F; Kermasha, S; Morin, A

    1995-11-01

    Three extracellular lipases were produced by batch fermentation of Pseudomonas putida ATCC 795, Aspergillus niger CBS 131.52 and Rhizopus oryzae ATCC 34612 during the late phase of growth, at 72, 96 and 96 h, respectively. The lipases were partially purified by (NH4)2SO4 fractionation. The lipase of P. putida was optimal at pH 8.0 whereas those from A. niger and R. oryzae were optimal at pH 7.5. The A. niger lipase had the lowest V max value (0.51×10(-3) U/min) and R. oryzae the highest (1.86×10(-3) U/min). The K m values for P. putida, A. niger and R. oryzae lipases were 1.18, 0.97, and 0.98 mg/ml, respectively. Native PAGE of the partially-purified lipase extracts showed two to four major bands. The interesterification of butter fat by A. niger lipase decreased the water activity as well as the hydrolytic activity. The A. niger lipase had the highest interesterification yield value (26%) and the R. oryzae lipase the lowest (4%). In addition, A. niger lipase exhibited the highest decrease (17%) in long-chain hypercholesterolemic fatty acids (C12:0, C14:0 and C16:0) at the sn-2-position; the P. putida lipase demonstrated the least favourable changes in specificity at the same position. PMID:24415019

  17. Optimization of glucose oxidase production by Aspergillus niger using genetic- and process-engineering techniques.

    Science.gov (United States)

    Hellmuth, K; Pluschkell, S; Jung, J K; Ruttkowski, E; Rinas, U

    1995-11-01

    Wild-type Aspergillus niger NRRL-3 was transformed with multiple copies of the glucose oxidase structural gene (god). The gene was placed under the control of the gpdA promoter of A. nidulans. For more efficient secretion the alpha-amylase signal peptide from A. oryzae was inserted in front of god. Compared to the wild type, the recombinant strain NRRL-3 (GOD3-18) produced up to four times more extracellular glucose oxidase under identical culture conditions. Addition of yeast extract (2 gl-1) to a mineral salts medium containing only glucose as carbon source increased volumetric and specific extracellular glucose oxidase activities by 130% and 50% respectively. With the same medium composition and inoculum size, volumetric and specific extracellular glucose oxidase activities increased more than ten times in bioreactor cultivations compared to shake-flask cultures. PMID:8590664

  18. Biosorption of C.I. Direct Blue 199 from aqueous solution by nonviable Aspergillus niger

    International Nuclear Information System (INIS)

    The capacity and mechanism with which nonviable Aspergillus niger removed the textile dye, C.I. Direct Blue 199, from aqueous solution was investigated using different parameters, such as initial dye concentration, pH and temperature. In batch experiments, the biosorption capacity increased with decrease in pH, and the maximum dye uptake capacity of the biosorbent was 29.96 mg g-1 at 400 mg L-1 dye concentration and 45 deg. C. The Langmuir and Freundlich models were able to describe the biosorption equilibrium of C.I. Direct Blue 199 onto the fungal biomass. Biosorption followed a pseudo-second order kinetic model with high correlation coefficients (r2 > 0.99). Thermodynamic studies revealed that the biosorption process was successful, spontaneous and endothermic in nature.

  19. Effect of Stirrer Speed and Aeration Rate on the Production of Glucose Oxidase by Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Jafari A.R.

    2007-01-01

    Full Text Available Dissolved oxygen tension and shear stress as two very important factors in fungal fermentation were studied in the batch cultures of Aspergillus niger. The intention was to maximize the total activity of glucose oxidase produced in a 5-1 bench-top bioreactor. 300 rpm found to be optimum for enzyme production, however in higher mixing rates higher growth was achieved. The maximum activity of glucose oxidase was obtained in 1.5 vvm while the best aeration rate for growth was 2 vvm. Glucose oxidase with the activity of 548 U mL-1 was produced in 1.5 vvm and 300 rpm as the optimum conditions.

  20. Refinement of the crystal structures of biomimetic weddellites produced by microscopic fungus Aspergillus niger

    Science.gov (United States)

    Rusakov, A. V.; Frank-Kamenetskaya, O. V.; Gurzhiy, V. V.; Zelenskaya, M. S.; Izatulina, A. R.; Sazanova, K. V.

    2014-05-01

    The single-crystal structures of four biomimetic weddellites CaC2O4 · (2 + x)H2O with different contents of zeolitic water ( x = 0.10-0.24 formula units) produced by the microscopic fungus Aspergillus niger were refined from X-ray diffraction data ( R = 0.029-0.038). The effect of zeolitic water content on the structural stability of weddellite was analyzed. The parameter a was shown to increase with increasing x due to the increase in the distance between water molecules along this direction. The water content and structural parameters of the synthesized weddellites are similar to those of weddellites from biofilms and kidney stones.

  1. Citric acid production by gamma irradiated aspergillus niger from treated beet molasses under different fermentation conditions

    International Nuclear Information System (INIS)

    The necessary treatments of beet molasses by addition of any the chelating agents potassium ferrocyanide and ethylenediamine tetraacetic acid (EDTA), to improve its suitability as a substrate for citric acid production by gamma irradiated inocula (at dose 0.4 KGy) of aspergillus niger EMCC 111 was studied. Addition of potassium ferrocyanide stimulated citric acid production and maximum production (10.92 g%) was obtained with 0.1 g% of ferrocyanide. In contrast, EDTA at 0.1 g% increased citric acid production but further addition of EDTA repressed the production. Addition of low molecular weight alcohols (methanol or ethanol)improved the yield of citric acid. Methanol and ethanol when added at concentration of 2%(v/v) elevate citric acid yield % to 47.58% and 46.51% respectively. 6 tabs

  2. Kinetics Studies on citric acid production by gamma ray induced mutant of Aspergillus niger

    International Nuclear Information System (INIS)

    Effect of cultural pH and incubation temperature on citric acid yield and kinetic patterns of citric acid fermentation by a natural isolate of aspergillus niger as CA16 and one of its gamma ray induced mutants were studied using cane molasses as growth and fermentation substrate. Mutant strain, 277/30 gave maximum citric acid yield of 85 g/l at pH 3.5 and 28 degree centigrade in molasses medium adjusted to 16% sugar and 25% prescott salt in the medium. Parent strain, CA16 gave a maximum yield of 34 g/l at pH 4.0 and 26 degree centigrade in molasses medium adjusted to 16% sugar and 100% prescott salt in the medium. In kinetic studies, strains showed combination kinetics of citric acid fermentation where product formation is directly related to growth and cell mass and indirectly related to carbohydrate uptake

  3. Improving Aspergillus niger as a production host through manipulation of pH responding transcription factors

    DEFF Research Database (Denmark)

    Poulsen, Lars; Bruno, K.S.; Thykær, Jette;

    Altering fluxes for overcoming metabolic bottlenecks have traditionally been approached by genetic engineering of a single or few metabolic genes. This strategy struggles to overcome the subjacent regulation thus the outcome has frequently shown to be of limited success. Transcription factors have......., 2008). In the present study the effect of modulation of transcription factors in Aspergillus niger, which is an industrially important micro-organism used in various processes including organic acid and enzyme production, was investigated. The strategy described in this work focuses on regulation...... connected to pH. It was chosen as an important process parameter, due to its significant influences on both organic acid and enzyme production. A previous transcription analysis identified several putative transcription factors with pH responding behavior (Andersen et al., 2009). A number of these genes...

  4. OPTIMIZATION OF EXTRACELLULAR TANNASE PRODUCTION BY ASPERGILLUS NIGER VAN TIEGHEM USING RESPONSE SURFACE METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Hamada Abou-Bakr

    2013-12-01

    Full Text Available Response surface methodology (RSM was used to optimize the production of tannase by a newly isolate of Aspergillus niger Van Tieghem using rotatable central composite design (RCCD. This statistical optimization process was carried out involving four of quantitative growth parameters (variables, namely tannic acid concentration, nitrogen source concentration, initial pH of the medium and inoculum size. A mathematical model expressing the production process of tannase by submerged fermentation (SmF technique was generated statistically in the form of a second order polynomial equation. The model indicated the presence of significant linear, quadratic and interaction effects of the studied variables on tannase production by the fungal isolate. The results showed maximum tannase production (580 U/50 ml medium at 2% tannic acid, 4 g/l sodium nitrate, pH 4 and inoculum size of 5×107 spores/50 ml medium, which was also verified by experimental data.

  5. Fumonisin B2 production by Aspergillus niger in Thai coffee beans

    DEFF Research Database (Denmark)

    Noonim, P.; Mahakarnchanaku, W.; Nielsen, Kristian Fog;

    2009-01-01

    During 2006 and 2007, a total of 64 Thai dried coffee bean samples (Coffea arabica) from two growing sites in Chiangmai Province and 32 Thai dried coffee bean samples (Coffea canephora) from two growing sites in Chumporn Province, Thailand, were collected and assessed for fumonisin contamination...... by black Aspergilli. No Fusarium species known to produce fumonisin were detected, but black Aspergilli had high incidences on both Arabica and Robusta Thai coffee beans. Liquid chromatography (LC) with high-resolution mass spectrometric (HRMS) detection showed that 67% of Aspergillus niger isolates from...... coffee beans were capable of producing fumonisins B2 (FB2) and B4 when grown on Czapek Yeast Agar with 5% NaCl. Small amounts (1-9.7 ng g-1) of FB2 were detected in seven of 12 selected coffee samples after ion-exchange purification and LC-MS/MS detection. Two samples also contained FB4...

  6. An acidic pectin lyase from Aspergillus niger with favourable efficiency in fruit juice clarification.

    Science.gov (United States)

    Xu, S X; Qin, X; Liu, B; Zhang, D Q; Zhang, W; Wu, K; Zhang, Y H

    2015-02-01

    The pectin lyase gene pnl-zj5a from Aspergillus niger ZJ5 was identified and expressed in Pichia pastoris. PNL-ZJ5A was purified by ultrafiltration, anion exchange and gel chromatography. The Km and Vmax values determined using citrus pectin were 0.66 mg ml(-1) and 32.6 μmol min(-1) mg(-1) , respectively. PNL-ZJ5A exhibited optimal activity at 43°C and retained activity over 25-50°C. PNL-ZJ5A was optimally active at pH 5 and effective in apple juice clarification. Compared with controls, PNL-ZJ5A increased the fruit juice yield significantly. Furthermore, PNL-ZJ5A reduced the viscosity of apple juice by 38.8% and increased its transmittance by 86.3%. PNL-ZJ5A combined with a commercial pectin esterase resulted in higher juice volume. PMID:25382689

  7. Partial purification and characterization of xylanase produced from aspergillus niger using wheat bran

    International Nuclear Information System (INIS)

    In present exploration, purification and characterization of xylanase was carried out to find its optimum conditions for maximum functionality. The xylanase (EC 3.2.1.8) synthesized by Aspergillus niger in submerged fermentation was partially purified and characterized for different parameters like temperature, pH and heat stability. The molecular mass determined through SDS-PAGE was found 30 kDa. The specific activity of the enzyme was raised from 41.85 to 613.13 with 48.63% yield just in a two step partial purification comprising ammonium sulphate precipitation and Sephadex gel filteration column chromatography. The partially purified enzyme was found to be optimally active at 60 degree C and 7.5 pH. Conclusively, for the application of xylanase in food, feed or paper manufacturing processes, it is necessary to consider its optimum pH and temperature. (author)

  8. Aspergillus niger: sua utilização na indústria farmacêutica

    OpenAIRE

    Afonso, Sara de Oliveira Mateus

    2015-01-01

    Dissertação para obtenção do grau de Mestre no Instituto Superior de Ciências da Saúde Egas Moniz Aspergillus niger é um fungo bastante utilizado na indústria farmacêutica e com muita importância a nível biotecnológico. Tem a capacidade de produzir compostos a nível industrial, como, ácido cítrico, ácido glucónico, ácido málico, várias enzimas e vitamina C, através de processos fermentativos. Também é utilizado para a execução de biotransformação de produtos já existentes, formando compost...

  9. Activity and stability of feruloyl esterase A from Aspergillus niger in ionic liquid systems

    DEFF Research Database (Denmark)

    Zeuner, Birgitte; Riisager, Anders; Meyer, Anne S.

    solvents that favour synthesis over hydrolysis, i.e. systems with low water content such as organic solvents or ionic liquids (ILs). The esterification of sinapic acid with glycerol catalysed by FAE A from Aspergillus niger (AnFaeA) in a series of ILs containing 15% (v/v) buffer showed that An......FaeA stability – and hence activity – was highly dependent on the anion nature: AnFaeA was stable and active for more than 2 hours in [PF6]--based ILs, but rapidly lost activity in [BF4]--based systems. This effect can be explained in terms of hydrogen bonding capacity of the two anions: As predicted by the......], but this is the first report on FAE stability in ILs [2]. COSMO-RS, which is now widely used for solvent screening in the complex IL systems [3], may be a valuable tool for fast enzyme stability predictions and/or solvent screening in the future....

  10. Identification of a Transcription Factor Controlling pH-Dependent Organic Acid Response in Aspergillus niger

    DEFF Research Database (Denmark)

    Poulsen, Lars; Andersen, Mikael Rørdam; Lantz, Anna Eliasson; Thykaer, Jette

    2012-01-01

    exhibiting an oxalate overproducing phenotype were identified. The yield of oxalate was increased up to 158% compared to the wild type and the corresponding transcription factor was therefore entitled Oxalic Acid repression Factor, OafA. Detailed physiological characterization of one of the ΔoafA mutants......, compared to the wild type, showed that both strains produced substantial amounts of gluconic acid, but the mutant strain was more efficient in re-uptake of gluconic acid and converting it to oxalic acid, particularly at high pH (pH 5.0). Transcriptional profiles showed that 241 genes were differentially......Acid formation in Aspergillus niger is known to be subjected to tight regulation, and the acid production profiles are fine-tuned to respond to the ambient pH. Based on transcriptome data, putative trans-acting pH responding transcription factors were listed and through knock out studies, mutants...

  11. Bioleaching of valuable metals from spent lithium-ion mobile phone batteries using Aspergillus niger

    Science.gov (United States)

    Horeh, N. Bahaloo; Mousavi, S. M.; Shojaosadati, S. A.

    2016-07-01

    In this paper, a bio-hydrometallurgical route based on fungal activity of Aspergillus niger was evaluated for the detoxification and recovery of Cu, Li, Mn, Al, Co and Ni metals from spent lithium-ion phone mobile batteries under various conditions (one-step, two-step and spent medium bioleaching). The maximum recovery efficiency of 100% for Cu, 95% for Li, 70% for Mn, 65% for Al, 45% for Co, and 38% for Ni was obtained at a pulp density of 1% in spent medium bioleaching. The HPLC results indicated that citric acid in comparison with other detected organic acids (gluconic, oxalic and malic acid) had an important role in the effectiveness of bioleaching using A. niger. The results of FTIR, XRD and FE-SEM analysis of battery powder before and after bioleaching process confirmed that the fungal activities were quite effective. In addition, bioleaching achieved higher removal efficiency for heavy metals than the chemical leaching. This research demonstrated the great potential of bio-hydrometallurgical route to recover heavy metals from spent lithium-ion mobile phone batteries.

  12. Pomelo peels as alternative substrate for extracellular pectinase production by Aspergillus niger HFM-8

    Directory of Open Access Journals (Sweden)

    Ibrahim, D.

    2013-12-01

    Full Text Available Aims: The aim of this work was to develop an effective bioprocess to enhance the pectinase production by solid-state cultures of Aspergillus niger HFM-8. Methodology and results: The pectinase production produced by A. niger HFM-8 was studied under solid state fermentation using Malaysian pomelo (Citrus grandis peel as the substrate. This local agricultural waste is rich with lignocellulolytic material including pectin acts as the inducer of pectinase production. Under optimized conditions, 5 g of 0.75 mm pomelo peel size, moisture content of 60% (v/w sterile distilled water pH 5.0, inoculums size of 1x10^4 spores/mL, cultivation temperature of room temperature (30 ± 2 °C, no mixing incurred and with the addition of 1% (w/w citrus pectin and 0.1% (w/w urea has produced pectinase production of 306.89 U/g substrate and 0.78 mg glucosamine/g substrate of fungal growth on the 8th day of cultivation. Conclusion, significance and impact of study: There was 48.82% increment in enzyme production after the improvement of parameters. It was found that pomelo peel is a suitable feedstock for pectinase production.

  13. A benzoate-activated promoter from Aspergillus niger and regulation of its activity.

    Science.gov (United States)

    Antunes, Mauricio S; Hodges, Thomas K; Carpita, Nicholas C

    2016-06-01

    The filamentous fungus Aspergillus niger is able to use benzoic acid as a sole carbon source by conversion to protocatechuic acid and subsequent metabolism. Synthesis of the first enzyme in this metabolic pathway, benzoate p-hydroxylase, is encoded by the bphA gene and positively regulated at the transcriptional level by benzoic acid. Methyl benzoate and para-aminobenzoate also act as inducers of the bphA gene. We show that bphA expression in A. niger in response to benzoate is confined to a 530-bp fragment from the bphA promoter region from -787 to -509 bp from the transcriptional start site. Electrophoretic mobility-shift assays show that a benzoate-response element, consisting of a single 6-bp sequence (5'-TAGTCA-3') within a 51-bp sequence in this region, is most likely to be involved in binding of one or more proteins that modulate the activity of the promoter in response to benzoic acid. We show through fusion of promoter fragments with the green fluorescent protein that the active sequences are located within a 200-bp sequence containing the TAGTCA benzoate-response element. Identification of the benzoate-response element in the bphA promoter region constitutes the first step in the development of a benzoate-inducible promoter system that could be used to control gene expression in fungi, and possibly in other organisms, such as plant and animal cells. PMID:26907094

  14. Process optimization of citric acid production from aspergillus niger using fuzzy logic design

    International Nuclear Information System (INIS)

    The inherent non-linearity of citric acid fermentation from Aspergillus niger renders its control difficult, so there is a need to fine-tune the bioreactor performance for maximum production of citric acid in batch culture. For this, fuzzy logic is becoming a popular tool to handle non-linearity of a batch process. The present manuscript deals with fuzzy logic control of citric acid accretion by A. niger in a stirred tank reactor using blackstrap sugarcane molasses as a basal fermentation medium. The customary batches were termed as control while those under fuzzy logic were experimental. The performance of fuzzy logic control of stirred tank reactor was found to be very encouraging for enhanced production of citric acid. The comparison of kinetic parameters showed improved citrate synthase ability of experimental culture (Yp/x = 7.042 g/g). When the culture grown on 150 g/l carbohydrates was monitored for Qp, Qs and Yp/s, there was significant enhancement in these variables over the control. Specific productivity of culture (qp = 0.070 g/g cells/h) was several fold increased. The enthalpy (HD = 70.5 kJ/mol) and entropy of activation (S = -144 J/mol/K) of enzyme for citric acid biosynthesis, free energies for transition state formation and substrate binding for sucrose hydrolysis of experimental were substantially improved. (author)

  15. Process optimization of citric acid production from aspergillus niger using fuzzy logic design

    International Nuclear Information System (INIS)

    The inherent non-linearity of citric acid fermentation from Aspergillus niger renders its control difficult, so there is a need to fine-tune the bioreactor performance for maximum production of citric acid in batch culture. For this, fuzzy logic is becoming a popular tool to handle non-linearity of a batch process. The present manuscript deals with fuzzy logic control of citric acid accretion by A. niger in a stirred tank reactor using blackstrap sugarcane molasses as a basal fermentation medium. The customary batches were termed as 'control' while those under fuzzy logic were 'experimental'. The performance of fuzzy logic control of stirred tank reactor was found to be very encouraging for enhanced production of citric acid. The comparison of kinetic parameters showed improved citrate synthase ability of experimental culture (Yp/x = 7.042 g/g). When the culture grown on 150 g/l carbohydrates was monitored for Qp, Qs and Yp/s, there was significant enhancement in these variables over the control. Specific productivity of culture (qp = 0.070 g/g cells/h) was several fold increased. The enthalpy (HD = 70.5 kJ/mol) and entropy of activation (S = -144 J/mol/K) of enzyme for citric acid biosynthesis, free energies for transition state formation and substrate binding for sucrose hydrolysis of experimental were substantially improved. (author)

  16. Microbially influenced corrosion of zinc and aluminium - Two-year subjection to influence of Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Juzeliunas, Eimutis [Institute of Chemistry, A.Gostauto 9, 01108 Vilnius (Lithuania)], E-mail: ejuzel@ktl.mii.lt; Ramanauskas, Rimantas; Lugauskas, Albinas; Leinartas, Konstantinas; Samuleviciene, Meilute; Sudavicius, Aloyzas; Juskenas, Remigijus [Institute of Chemistry, A.Gostauto 9, 01108 Vilnius (Lithuania)

    2007-11-15

    Aspergillus niger. Tiegh., a filamentous ascomycete fungus, was isolated from the metal samples exposed to marine, rural and urban sites in Lithuania. Al and Zn samples were subjected to two-year influence of A. niger under laboratory conditions in humid atmosphere. Electrochemical impedance spectroscopy (EIS) ascertained microbially influenced corrosion acceleration (MICA) of Zn and inhibition (MICI) of Al. EIS data indicated a two-layer structure of corrosion products on Zn. The microorganisms reduced the thickness of the inner layer, whose passivating capacity was much higher when compared to that of the outer layer. An increase in aluminium oxide layer resistance but decrease in the layer thickness implied that MICI affected primarily the sites of localized corrosion of Al (pores, micro-cracks, etc.). X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) studies indicated that bioproducts (i.e. organic acids) did not form crystalline phases with corrosion products of zinc. The study suggested a hypothesis that microorganisms could be used as corrosion protectors instead of toxic chemicals, application of which tends to be increasingly restricted.

  17. Low-cost carbon sources for the production of a thermostable xylanase by Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Ana Cláudia Elias Pião Benedetti

    2013-01-01

    Full Text Available A strain of the filamentous fungus Aspergillus niger was isolated and shown to possess extracellular xylanolytic activity. These enzymes have biotechnological potential and can be employed in various industries. This fungus produced its highest xylanase activity in a medium made up of 0.1% CaCO3 , 0.5% NaCl, 0.1% NH4 Cl, 0.5% corn steep liquor and 1% carbon source, at pH 8.0. A lowcost hemicellulose residue (powdered corncob proved to be an excellent inducer of the A. niger xylanolytic complex. Filtration of the crude culture medium with suspended kaolin was ideal for to clarify the extract and led to partial purification of the xylanolytic activity. The apparent molecular mass of the xylanase was about 32.3 kDa. Maximum enzyme activity occurred at pH 5.0 and 55-60ºC. Apparent Km was 10.41 ± 0.282 mg/mL and Vmax was 3.32 ± 0.053 U/mg protein, with birchwood xylan as the substrate. Activation energy was 4.55 kcal/mol and half-life of the crude enzyme at 60ºC was 30 minutes. Addition of 2% glucose to the culture medium supplemented with xylan repressed xylanase production, but in the presence of xylose the enzyme production was not affected.

  18. Recovery of metals from low-grade ores by Aspergillus niger

    International Nuclear Information System (INIS)

    The main concern of this study is to develop a feasible and economical technique to microbially recover metals from oxide low-grade ores. Owing to the significant quantities of metals that are embodied in low - grade ores and mining residues, these are considered new sources of metals. On the other hand, they potentially endanger the environment, as the metals they contain may be released to the environment in a hazardous form. Hence, mining industries are seeking an efficient technique to handle these ores. Pyrometallurgical and hydrometallurgical techniques are either very expensive, energy intensive or have a negative impact on the environment. For these reasons, biohydrometallurgical techniques are coming into perspective. In this study, by employing Aspergillus niger, the feasibility of recovery of metals from a mining residue is shown. A. niger exhibits good potential in generating a variety of organic acids effective for metal solubilization. Organic acid effectiveness was enhanced when sulphuric acid was added to the medium. Different agricultural wastes such as potato peels were tested. In addition to this, different auxiliary processes were tried in order to either elevate the efficiency or reduce costs. Finally, maximum solubilization of 68%, 46% and 34% were achieved for copper, zinc and nickel, respectively. Also iron codissolution was minimized as only 7% removal occurred. (author)

  19. Bioleaching of heavy metals from a low-grade mining ore using Aspergillus niger.

    Science.gov (United States)

    Mulligan, Catherine N; Kamali, Mahtab; Gibbs, Bernard F

    2004-07-01

    The main concern of this study is to develop a feasible and economical technique to microbially recover metals from oxide low-grade ores. Owing to the significant quantities of metals that are embodied in low-grade ores and mining residues, these are potential viable sources of metals. In addition, they potentially endanger the environment, as the metals they contain may be released to the environment in hazardous form. Hence, mining industries are seeking an efficient, economic technique to handle these ores. Pyrometallurgical and hydrometallurgical techniques are either very expensive, energy intensive or have a negative impact on the environment. For these reasons, biohydrometallurgical techniques are coming into perspective. In this study, by employing Aspergillus niger, the feasibility of recovery of metals from a mining residue is shown. A. niger exhibits good potential in generating a variety of organic acids effective for metal solubilization. Organic acid effectiveness was enhanced when sulfuric acid was added to the medium. Different agricultural wastes such as potato peels were tested. In addition, different auxiliary processes were evaluated in order to either elevate the efficiency or reduce costs. Finally, maximum solubilization of 68%, 46% and 34% were achieved for copper, zinc and nickel, respectively. Also iron co-dissolution was minimized as only 7% removal occurred. PMID:15177728

  20. Recovery of metals from low-grade ores by Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Kamali, M.; Mulligan, C.N. [Concordia Univ., Dept. of Building, Civil and Environmental Engineering, Montreal, Quebec (Canada)]. E-mail: mulligan@civil.concordia.ca

    2002-06-15

    The main concern of this study is to develop a feasible and economical technique to microbially recover metals from oxide low-grade ores. Owing to the significant quantities of metals that are embodied in low - grade ores and mining residues, these are considered new sources of metals. On the other hand, they potentially endanger the environment, as the metals they contain may be released to the environment in a hazardous form. Hence, mining industries are seeking an efficient technique to handle these ores. Pyrometallurgical and hydrometallurgical techniques are either very expensive, energy intensive or have a negative impact on the environment. For these reasons, biohydrometallurgical techniques are coming into perspective. In this study, by employing Aspergillus niger, the feasibility of recovery of metals from a mining residue is shown. A. niger exhibits good potential in generating a variety of organic acids effective for metal solubilization. Organic acid effectiveness was enhanced when sulphuric acid was added to the medium. Different agricultural wastes such as potato peels were tested. In addition to this, different auxiliary processes were tried in order to either elevate the efficiency or reduce costs. Finally, maximum solubilization of 68%, 46% and 34% were achieved for copper, zinc and nickel, respectively. Also iron codissolution was minimized as only 7% removal occurred. (author)

  1. Bioprocessing of citrus waste peel for induced pectinase production by Aspergillus niger; its purification and characterization

    Directory of Open Access Journals (Sweden)

    Ishtiaq Ahmed

    2016-04-01

    Full Text Available Agro-industrial residues are primarily composed of complex polysaccharides that strengthen microbial growth for the production of industrially important enzymes. Pectinases are one of the most widely disseminated enzymes in bacteria, fungi and plants. Czapeck media supplemented with orange waste peel as carbon source under submerged fermentation process Aspergillus niger presenting the preeminent enzymatic production. On partial optimization culture showed the maximum enzyme yield (117.1 ± 3.4 μM/mL/min at 30 °C in an orange waste peel medium having pH 5.5 and substrate concentration (4% after 5th day of fermentation. The produced enzyme was purified by ammonium sulfate precipitation and ion exchange chromatography. A purification fold of 5.59 with specific activity and % recovery of 97.2 U/mg and 12.96% was achieved respectively after gel filtration chromatographic technique. The molecular weight of purified pectinase from A. niger was 30 kDa evidenced by SDS-PAGE. Pectinase activity profile showed purified enzyme was optimally active at pH = 7 and 55 °C. The maximum production of pectinase in the presence of cheaper substrate at low concentration makes the enzyme useful in industrial sectors especially for textile and juice industry.

  2. Production of Proteolytic Enzymes by a Keratin-Degrading Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Fernanda Cortez Lopes

    2011-01-01

    Full Text Available A fungal isolate with capability to grow in keratinous substrate as only source of carbon and nitrogen was identified as Aspergillus niger using the sequencing of the ITS region of the rDNA. This strain produced a slightly acid keratinase and an acid protease during cultivation in feather meal. The peak of keratinolytic activity occurred in 48 h and the maximum proteolytic activity in 96 h. These enzymes were partly characterized as serine protease and aspartic protease, respectively. The effects of feather meal concentration and initial pH on enzyme production were evaluated using a central composite design combined with response surface methodology. The optimal conditions were determined as pH 5.0 for protease and 7.8 for keratinase and 20 g/L of feather meal, showing that both models were predictive. Production of keratinases by A. niger is a less-exploited field that might represent a novel and promising biotechnological application for this microorganism.

  3. GC--MS analysis reveals production of 2--Phenylethanol from Aspergillus niger endophytic in rose.

    Science.gov (United States)

    Wani, Masood Ahmed; Sanjana, Kaul; Kumar, Dhar Manoj; Lal, Dhar Kanahya

    2010-02-01

    Endophytes include all organisms that during a variable period of their life, colonize the living internal tissues of their hosts without causing detectable symptoms. Several fungal endophytes have been isolated from a variety of plant species which have proved themselves as a rich source of secondary metabolites. The reported natural products from endophytes include antibiotics, immunosuppresants, anticancer compounds, antioxidant agents, etc. For the first time Rosa damacaena (rose) has been explored for its endophytes. The rose oil industry is the major identified deligence for its application in perfumery, flavouring, ointments, and pharmaceuticals including various herbal products. During the present investigation fungal endophytes were isolated from Rosa damacaena. A total of fifty four isolates were isolated out of which sixteen isolates were screened for the production of secondary metabolites. GCMS analysis reveals the production of 2-phenylethanol by one of the isolates JUBT 3M which was identified as Aspergillus niger. This is the first report of production of 2-phenylethanol from endophytic A. niger. 2-phenylethanol is an important constituent of rose oil constituting about 4.06% of rose oil. Presence of 2-phenylethanol indicates that the endophyte of rose may duplicate the biosynthesis of phenyl propanoids by rose plant. Besides this, the other commercial applications of phenylethanol include its use in antiseptics, disinfectants, anti-microbials and preservative in pharmaceuticals. PMID:20082377

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

    Science.gov (United States)

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

    2016-06-01

    We present the multiplex PCR data for the presence/absence of genes involved in OTA and FB2 biosynthesis in Aspergillus niger/Aspergillus welwitschiae strains isolated from different food substrates in Brazil. Among the 175 strains analyzed, four mPCR profiles were found: Profile 1 (17%) highlights strains harboring in their genome the pks, radH and the fum8 genes. Profile 2 (3.5%) highlights strains harboring genes involved in OTA biosynthesis i.e. radH and pks. Profile 3 (51.5%) highlights strains harboring the fum8 gene. Profile 4 (28%) highlights strains not carrying the genes studied herein. This research content is supplemental to our original research article, "Prospecting for the incidence of genes involved in ochratoxin and fumonisin biosynthesis in Brazilian strains of A. niger and A. welwitschiae" [1]. PMID:27054181

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

    Science.gov (United States)

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

    2016-01-01

    We present the multiplex PCR data for the presence/absence of genes involved in OTA and FB2 biosynthesis in Aspergillus niger/Aspergillus welwitschiae strains isolated from different food substrates in Brazil. Among the 175 strains analyzed, four mPCR profiles were found: Profile 1 (17%) highlights strains harboring in their genome the pks, radH and the fum8 genes. Profile 2 (3.5%) highlights strains harboring genes involved in OTA biosynthesis i.e. radH and pks. Profile 3 (51.5%) highlights strains harboring the fum8 gene. Profile 4 (28%) highlights strains not carrying the genes studied herein. This research content is supplemental to our original research article, “Prospecting for the incidence of genes involved in ochratoxin and fumonisin biosynthesis in Brazilian strains of A. niger and A. welwitschiae” [1]. PMID:27054181

  6. Stimulation of germination of conidium Aspergillus niger, a citric acid producer, under the action of mutagenic factors

    International Nuclear Information System (INIS)

    The action of low doses of various mutagens, namely, 2% cyclophosphane solution (30 min), 1% thiophosphamide solution (30 min), 0.05% nitrosomethylurea solution (30 and 60 min), γ-rays (10 krads) and UV-rays (10000 erg/mm2) stimulates germination of conidium Aspergillus niger, a citric acid producer. At the above-mentioned doses of mutagens, a minor quantity of morphological varieties are formed, and the variability value of acid production by Asp. niger is maintained at the spontaneous level

  7. A modelling implementation of climate change on biodegradation of Low-Density Polyethylene (LDPE) by Aspergillus niger in soil

    OpenAIRE

    Farzin Shabani; Lalit Kumar; Atefeh Esmaeili

    2015-01-01

    Aim:  To model the areas becoming and remaining highly suitable for Aspergillus niger growth over the next ninety years by future climate alteration, in relation to the species’ potential enhancement of Low Density Polyethylene (LDPE) biodegradation in soil. Location:  Global scale Methods:  Projections of A. niger growth suitability for 2030, 2050, 2070 and 2100 were made using the A2 emissions scenario together with two Global Climate Models (GCMs): the CSIRO-Mk3.0 (CS) model and the ...

  8. Aspergillus niger biofilms for celulasas production: some structural and physiological aspects

    Directory of Open Access Journals (Sweden)

    Gretty K. Villena

    2013-06-01

    Full Text Available Aspergillus niger biofilms developed on polyester cloth were evaluated considering two aspects related to the growth on surfaces: structure and physiological behavior focused on cellulase production. The biofilm structure was assessed by using electron scanning microphotographs from inoculation and adsorption to 120 h growth. The microphotographs show that biofilm formation can be divided into three phases: 1 Adhesion, which is strongly increased by Aspergillus spore hydrophobicity; 2 Initial growth and development phase from spore germination, that begins 4 to 10 h after inoculation and continues up to 24 h when almost all available surface has been colonized; 3 Maturation phase in which biomass density is highly increased from 48 h after inoculation until 120 h growth when an internal channel organization that assures medium flow through biofilm is clearly evident as it is frequently reported for bacterial biofilms.Biofilm cellulolytic enzyme activity and productivity were also evaluated, being up to 40% and 55%, respectively, higher than that attained by freely suspended cultures. These results are in agreement with the behavior of most surface living microorganisms, which generally show a higher metabolic activity because of a differential gene expression. This work is a first attempt to understand the structure and physiology of industrial filamentous fungal biofilms as a response to the scarce available information in comparison with the vast and detailed information related to bacterial and pathogenic yeast biofilms.

  9. Clarification of Tomato Juice with Polygalacturonase Obtained from Tomato Fruits Infected by Aspergillus niger.

    Science.gov (United States)

    Ajayi, A A; Peter-Albert, C F; Akeredolu, M; Shokunbi, A A

    2015-02-01

    Two varieties of tomato fruits commonly available in Nigerian markets are the Roma VF and Ibadan local varieties of tomato fruits. The Roma VF fruits are oval in shape. It is a common type of cultivar in the Northern region of Nigeria and it is not susceptible to cracking. The Ibadan local variety of tomato fruits is a local variety commonly found on farmers fields in South-western region of Nigeria. They are highly susceptible to cracking. The Ibadan local variety was employed for this research. There are lots of benefits derived from the consumption of tomato fruits. The fruits can be made into tomato juice clarified with pectinases. Polygalacturonase is one of the pectinases used commercially in the clarification of fruit juice from different fruits. This study examined the production of polygalacturonase during the deterioration of tomato fruits by Aspergillus niger and the role of the purified polygalacturonase in the clarification of tomato juice. Tomato fruits of the Ibadan local variety were inoculated with mycelia discs containing spores of a 96-h-old culture of Aspergillus niger served as the inoculum. The organism from the stock culture was subcultured onto potato dextrose agar plates. The extraction of polygalacturonase after 10 days of incubation at 27 degrees C was carried out by homogenizing the fruits with liquid extractant using the MSE homogenizer after the deteriorated fruits had been chilled for 30 min inside a freezer. Control fruits were similarly treated except that sterile potato dextrose agar served as the inoculum. The effect of different temperature of incubation and different volume of enzyme on the tomato juice from the tomato fruits was investigated. Extracts from the inoculated fruits exhibited appreciable polygalacturonase activity. The juice with polygalacturonase was visually clearer and more voluminous than the juice treated with water for all parameters studied. The highest volume of juice was obtained after an incubation period

  10. The Changes of Elements Composition in Aspergillus niger and Aspergillus terreus at Different Co2+, Cd2+ and Pb2+ Concentrations Using X-rays Microanalysis

    International Nuclear Information System (INIS)

    X-ray microanalysis in electron microscope allows simultaneous detection and quantitative analysis of several elements so it contributes to understand the role of ions in physiological processes. Energy dispersive X-ray (EDX) analysis used to detect the changes in elements levels in Aspergillus niger and Aspergillus terreus when allowing to grow on Czapek's Dox liquid media amended with different Co2+, Cd2+ and Pb2+ concentrations and these changes may play a role in fungal uptake for these heavy metal ions. Results showed that Ca, Zn and Cu levels in both fungal isolates significantly decreased (P<0.05) when concentrations of used metal ions increased, also O, Na, Cl and K levels for A. niger and C and P for A. terreus recorded significant reduction (P<0.05) in their percentages. Also, the results revealed that, C and P for A. niger and O, Na, Mg, Cl and K levels for A. terreus significantly increased (P<0.05) as a result of increasing metal ions concentrations. Lack of Cd and Pb peaks in X-ray spectrum for A. terreus led this work to conclude that, A. niger was more effective than A. terreus in Co, Cd, Pb uptake into fungal biomass. The increase or decrease of levels of detected elements could be related to the difference between two fungal isolates in uptake certain heavy metal ion (Co, Cd, Pb)

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

    DEFF Research Database (Denmark)

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

    2004-01-01

    Two recombinant strains of Aspergillus niger (NW 297-14 and NW297-24) producing a heterologous lipase from Thermomyces lanuginosus were constructed. The heterologous lipase was expressed using the TAKA amylase promoter from Aspergillus oryzae. The production kinetics of the two strains on different...... shows that it is possible to obtain high productivities of heterologous fungal enzymes in A. niger. However, SDS-PAGE analysis showed that most of the produced lipase was bound to the cell wall....... carbon sources in batch and carbon-limited chemostat cultivations were evaluated. In batch cultivations, the highest total product yield coefficient (Y-xp (total)), given as the sum of extracellular and intracellular yields, was obtained during growth on glucose for the transformant strain NW297-24 (5...

  12. Study on the molecular basis of glucoamylase overproduc-tion of a mutant strain Aspergillus niger T21

    Institute of Scientific and Technical Information of China (English)

    FAN; Xiaochun

    2001-01-01

    [1]Qiao, D., Tang, G., Zhong, L. et al., The overall analysis and comparison of the expression of glucoamylase in the over-production strain A. niger T21 and its original strain A. niger 3.795, Acta Microbiologica Sinica (in Chinese), 1997, 37(5): 349.[2]Zhong, L, Qiao, D, Tang, G. et al., Cloning, sequencing and comparison of the 5′-flanking regions of glaA gene from high and low glucoamylase producing strains of Aspergillus niger, Acta Microbiologica Sinica (in Chinese), 1996, 36: 181.[3]Qiao, D., Zhong, L., Tang, G. et al., Cloning and sequencing of glucoamylase gene from Aspergillus niger 3.795, Chinese J. Biochem. and Mol. Biology (in Chinese), 1998, 14: 254.[4]Zhong, L., Fan, X., Tang, G., Cotransformation of glucoamylase overproducing strain Aspergillus niger T21 with niaD and uidA gene, Mycosystema (in Chinese), 1999, 18: 172.[5]Roberts, I. N., Oliver, R. P., Punt, P. J. et al., Expression of the Escherichia coli b-glucuronidase gene in industrial and phytopathogenic filamentous fungi, Curr. Genet., 1989, 15: 177.[6]Lowry, O. H., Rosebrough, N. J., Farr, A. L. et al., Protein measurement with the folin phenol reagent, J. Biochem., 1951, 193: 268.[7]Zhu, H., Qu, F., Zhu, L., Isolation of genomic DNAs from fungi using benzyl chloride, Acta Mycologica Sinica (in Chi-nese), 1994, 13: 34.[8]Verwoerd, T. C., Dekker, B. M. M., Hoekema, A., A small-scale procedure for the rapid isolation of plant RNAs, Nucleic Acids Research, 1989, 17: 2362.[9]Campbell, E. I., Unkles, S. E., Marco, J. A. et al., Improved transformation efficiency of Aspergillus niger using the ho-mologous niaD gene for nitrate reductase, Curr. Genet., 1989, 16: 53.[10]Fowler, T., Berka, R. M., Ward, M., Regulation of the glaA gene of Aspergillus niger, Curr. Genet., 1990, 18: 537.[11]Verdoes, J. C., Punt, P. J., Stouthamer, A. H. et al., The effect of multiple copies of the upstream region on expression of the Aspergillus niger glucoamylase

  13. Bioleaching of incineration fly ash by Aspergillus niger – precipitation of metallic salt crystals and morphological alteration of the fungus

    OpenAIRE

    Tong-Jiang Xu; Thulasya Ramanathan; Yen-Peng Ting

    2014-01-01

    This study examines the bioleaching of municipal solid waste incineration fly ash by Aspergillus niger, and its effect on the fungal morphology, the fate of the ash particles, and the precipitation of metallic salt crystals during bioleaching. The fungal morphology was significantly affected during one-step and two-step bioleaching; scanning electron microscopy revealed that bioleaching caused distortion of the fungal hyphae (with up to 10 μm hyphae diameter) and a swollen pellet structure. I...

  14. Immobilization of Aspergillus niger F7-02 Lipase in Polysaccharide Hydrogel Beads of Irvingia gabonensis Matrix

    OpenAIRE

    Safaradeen Olateju Kareem; Olayinka Quadri Adio; Michael Bamitale Osho

    2014-01-01

    The potential of polysaccharide Irvingia gabonensis matrix as enzyme immobilization support was investigated. Lipase of Aspergillus niger F7-02 was immobilized by entrapment using glutaraldehyde as the cross-linking agent and stabilized in ethanolic-formaldehyde solution. The pH and temperature stability and activity yield of the immobilized enzyme were determined. Such parameters as enzyme load, bead size, number of beads, and bead reusability were also optimized. Adequate gel strength to fo...

  15. Acción del Aspergillus niger sobre la fibra de rayón-viscosa en presentaciones diferentes

    OpenAIRE

    García Vargas, Minerva Cristina; Riva Juan, Mª del Carmen

    2003-01-01

    Se describen los resultados de la investigación relacionada con la acción del hongo Aspergillus niger sobre las propiedades físicas de la fibra rayón-viscosa de distintas características (título, corte, tenacidad en húmedo y porcentaje de elongación). El biodeterioro se valora en términos de cambios en la resistencia a la rotura y porcentajes de alargamiento.

  16. Alkaline thermostable pectinase enzyme from Aspergillus niger strain MCAS2 isolated from Manaslu Conservation Area, Gorkha, Nepal

    OpenAIRE

    Khatri, Bhim Prakash; Bhattarai, Tribikram; Shrestha, Sangita; Maharjan, Jyoti

    2015-01-01

    Pectinase enzymes are one of the commercially important enzymes having great potential in various industries especially in food industry. Pectinases accounts for 25 % of global food enzymes produced and their market is increasing day by day. Therefore, the exploration of microorganism with novel characteristics has always been the focus of the research. Microorganism dwelling in unique habitat may possess unique characteristics. As such, a pectinase producing fungus Aspergillus niger strain M...

  17. Selection and characterisation of a xylitol-derepressed Aspergillus niger mutant that is apparently impaired in xylitol transport

    OpenAIRE

    Vondervoort, van de, P.J.I.; Groot, de, W.T.; Ruijter, G.J.G.; J. Visser

    2006-01-01

    Aspergillus niger is known for its biotechnological applications, such as the use of xylanase enzyme for the degradation of hemicellulose. Depending on culture conditions, several polyols may also be accumulated, such as xylitol during D-xylose oxidation. Also during industrial fermentation of xylose for the production of fuel ethanol by recombinant yeast, xylitol is a by-product. We studied xylitol metabolism by isolating mutants that have impaired xylitol-mediated repression. Genetic and bi...

  18. Proteomic analysis of the secretory response of Aspergillus niger to D-maltose and D-xylose

    OpenAIRE

    Ferreira de Oliveira, J.M.P.; Passel,; Schaap, P.J.; Graaff, de, F.M.

    2011-01-01

    Fungi utilize polysaccharide substrates through extracellular digestion catalyzed by secreted enzymes. Thus far, protein secretion by the filamentous fungus Aspergillus niger has mainly been studied at the level of individual proteins and by genome and transcriptome analyses. To extend these studies, a complementary proteomics approach was applied with the aim to investigate the changes in secretome and microsomal protein composition resulting from a shift to a high level secretion condition....

  19. Proteomic Analysis of the Secretory Response of Aspergillus niger to D-Maltose and D-Xylose

    OpenAIRE

    Ferreira de Oliveira, José Miguel P.; van Passel, Mark W. J.; Schaap, Peter J; de Graaff, Leo H

    2011-01-01

    Fungi utilize polysaccharide substrates through extracellular digestion catalyzed by secreted enzymes. Thus far, protein secretion by the filamentous fungus Aspergillus niger has mainly been studied at the level of individual proteins and by genome and transcriptome analyses. To extend these studies, a complementary proteomics approach was applied with the aim to investigate the changes in secretome and microsomal protein composition resulting from a shift to a high level secretion condition....

  20. Praperlakuan Fisik Dan Biologi Terhadap Biomassa Eceng Gondok Untuk Produksi Enzim Selulase Oleh Aspergillus Niger Dan Trichoderma Reesei

    OpenAIRE

    Amriani, Feni

    2015-01-01

    The Overgrowth of water hyacinth leads to eutrophication of water bodies as it exhausts nutrient and oxygen contents in water. However, it can be potentially used as lignocellulose biomass for cellulase production by several types of microbes such as Aspergillus niger and Trichoderma reesei. Physical pretreatment is conducted by size reduction of biomass and biological pretreatment by relying white rot fungus in which used to degrade lignin and improve accessibility of microbes to the cellulo...

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

    Directory of Open Access Journals (Sweden)

    Frisvad Jens C

    2009-12-01

    Full Text Available Abstract Background Fumonisins are economically important mycotoxins which until recently were considered to originate from only a few Fusarium species. However recently a putative fumonisin gene cluster was discovered in two different Aspergillus niger strains followed by detection of an actual fumonisin B2 (FB2 production in four strains of this biotechnologically important workhorse. Results In the present study, a screening of 5 A. niger strains and 25 assumed fumonisin producing Fusarium strains from 6 species, showed that all 5 A. niger strains produced FB2 and 23 of 25 Fusarium produced fumonisin B1 and other isoforms (fumonisin B2 and B3. Five A. niger and five Fusarium spp. were incubated at six different temperatures from 15-42°C on Czapek Yeast Agar +5% salt or Potato Dextrose Agar. A. niger had the highest production of FB2 at 25-30°C whereas Fusarium spp. had the maximal production of FB1 and FB2 at 20-25°C. Addition of 2.5-5% NaCl, or 10-20% sucrose increased the FB2 production of A. niger, whereas addition of glycerol reduced FB2 production. All three water activity lowering solutes reduced the fumonisin production of the Fusarium species. Conclusion The present study shows that the regulation of fumonisin production is very different in A. niger and Fusarium, and that food and feeds preserved by addition of sugar or salts may be good substrates for fumonisin B2 production by A. niger.

  2. Optimization of aspergillus niger nutritional conditions using statistical experimental methods for bio-recovery of manganese from pyrolusite

    International Nuclear Information System (INIS)

    Optimization of aspergillus niger nutritional conditions using statistical experimental methods for bio-recovery of manganese from pyrolusite Mujeeb-ur-rahman, Mohammed Masoom Yasinzai, Rasool Bakhsh Tareen, Asim Iqbal, Ejaz Ali Odhano, Shereen Gul. The nutritional requirements for Aspergillus niger PCSIR-06 for bio-recovery of manganese from pyrolusite ore were optimized. Box-Bhenken design and response surface methodology were used for designing of experiment and statistical analysis of the results. This procedure limited the number of actual experiments to 54 for studying the possible interaction between six nutrients. The optimum concentration of the nutrients were Sucrose 148.5 g/L, KH/sub 2/PO/sub 4/ 0.50 g/L, NH/sub 4/NO/sub 3/ 0.33 g/L, MgSO/sub 4/ 0.41 g/L, Zn 23.76 mg/L, Fe 0.18 mg/L for Aspergillus niger to achieve maximum bio-recovery of manganese (82.47 +- 5.67%). The verification run confirmed the predicted optimized concentration of all the six ingredients for maximum bio leaching of manganese and successfully confirmed the use of Box-Bhenken experimental design for maximum bio-recovery. Results also revealed that small and less time consuming experimental designs could be efficient for optimization of bio-recovery processes. (author)

  3. Biological Control of Meloidogyne incognita by Aspergillus niger F22 Producing Oxalic Acid.

    Directory of Open Access Journals (Sweden)

    Ja Yeong Jang

    Full Text Available Restricted usage of chemical nematicides has led to development of environmentally safe alternatives. A culture filtrate of Aspergillus niger F22 was highly active against Meloidogyne incognita with marked mortality of second-stage juveniles (J2s and inhibition of egg hatching. The nematicidal component was identified as oxalic acid by organic acid analysis and gas chromatography-mass spectroscopy (GC-MS. Exposure to 2 mmol/L oxalic acid resulted in 100% juvenile mortality at 1 day after treatment and suppressed egg hatching by 95.6% at 7 days after treatment. Oxalic acid showed similar nematicidal activity against M. hapla, but was not highly toxic to Bursaphelenchus xylophilus. The fungus was incubated on solid medium and dried culture was used for preparation of a wettable powder-type (WP formulation as an active ingredient. Two WP formulations, F22-WP10 (ai 10% and oxalic acid-WP8 (ai 8%, were prepared using F22 solid culture and oxalic acid. In a field naturally infested with M. incognita, application of a mixture of F22-WP10 + oxalic acid-WP8 at 1,000- and 500-fold dilutions significantly reduced gall formation on the roots of watermelon plants by 58.8 and 70.7%, respectively, compared to the non-treated control. The disease control efficacy of the mixture of F22-WP10 + oxalic acid-WP8 was significantly higher than that of a chemical nematicide, Sunchungtan (ai 30% fosthiazate. These results suggest that A. niger F22 can be used as a microbial nematicide for the control of root-knot nematode disease.

  4. Structural features of sugars that trigger or support conidial germination in the filamentous fungus Aspergillus niger.

    Science.gov (United States)

    Hayer, Kimran; Stratford, Malcolm; Archer, David B

    2013-11-01

    The asexual spores (conidia) of Aspergillus niger germinate to produce hyphae under appropriate conditions. Germination is initiated by conidial swelling and mobilization of internal carbon and energy stores, followed by polarization and emergence of a hyphal germ tube. The effects of different pyranose sugars, all analogues of d-glucose, on the germination of A. niger conidia were explored, and we define germination as the transition from a dormant conidium into a germling. Within germination, we distinguish two distinct stages, the initial swelling of the conidium and subsequent polarized growth. The stage of conidial swelling requires a germination trigger, which we define as a compound that is sensed by the conidium and which leads to catabolism of d-trehalose and isotropic growth. Sugars that triggered germination and outgrowth included d-glucose, d-mannose, and d-xylose. Sugars that triggered germination but did not support subsequent outgrowth included d-tagatose, d-lyxose, and 2-deoxy-d-glucose. Nontriggering sugars included d-galactose, l-glucose, and d-arabinose. Certain nontriggering sugars, including d-galactose, supported outgrowth if added in the presence of a complementary triggering sugar. This division of functions indicates that sugars are involved in two separate events in germination, triggering and subsequent outgrowth, and the structural features of sugars that support each, both, or none of these events are discussed. We also present data on the uptake of sugars during the germination process and discuss possible mechanisms of triggering in the absence of apparent sugar uptake during the initial swelling of conidia. PMID:23995938

  5. Lactobacillus brevis-based bioingredient inhibits Aspergillus niger growth on pan bread

    Directory of Open Access Journals (Sweden)

    Mariaelena Di Biase

    2014-11-01

    Full Text Available Bread shelf life is generally compromised by fungi mainly belonging to Aspergillus and Penicillium genera, which colonise the surface of the product within few days from the production. The aim of this study was to select a Lactobacillus brevis-based bioingredient (LbBio able to inhibit the growth of Aspergillus niger ITEM5132 on pan bread in order to prolong its shelf life. Four LbBio formulations, obtained by growing a selected L. brevis strain in a flour-based medium containing different carbon sources or acid precursors (fructose, LbBio1; fructose and maltose, LbBio2; α-chetoglutaric acid, LbBio3; short-chain fructooligosaccharides, LbBio4, were evaluated for their content of organic acids (lactic, acetic, propionic, phenyllactic, 4-hydroxy-phenyllactic, valeric, isovaleric acids. The LbBio formulations were applied in yeast-leavened bread during bread-making trials and the resulting products were inoculated after baking with A. niger spore’s suspension and the fungal growth was monitored during storage (25°C for 6 days. The formulation showing the highest inhibitory activity was separated by ultra-filtration method, and whole and fractions obtained were evaluated for their in vitro activity. The fraction showing the highest activity was further separated by gel-filtration and the resulting products were investigated for their protein content and in vitro inhibition. The results from the bread-making trials performed using different formulations of LbBio showed a delay in fungal growth (1 day respect to the bread not containing the bioingredient (control or including calcium propionate (0.3% w/w. The formulation LbBio2, prepared with fructose and maltose 1% (w/vol, contained the highest amount of total organic acids, including phenyllactic and hydroxyl-phenyllactic acids, and reduced the visual spoilage of bread. This formulation was separated by ultra-filtration and fractions containing metabolites with molecular weight higher than 30 k

  6. Secretion and properties of a hybrid Kluyveromyces lactis-Aspergillus niger β-galactosidase

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    Becerra Manuel

    2006-12-01

    Full Text Available Abstract Background The β-galactosidase from Kluyveromyces lactis is a protein of outstanding biotechnological interest in the food industry and milk whey reutilization. However, due to its intracellular nature, its industrial production is limited by the high cost associated to extraction and downstream processing. The yeast-system is an attractive method for producing many heterologous proteins. The addition of a secretory signal in the recombinant protein is the method of choice to sort it out of the cell, although biotechnological success is not guaranteed. The cell wall acting as a molecular sieve to large molecules, culture conditions and structural determinants present in the protein, all have a decisive role in the overall process. Protein engineering, combining domains of related proteins, is an alternative to take into account when the task is difficult. In this work, we have constructed and analyzed two hybrid proteins from the β-galactosidase of K. lactis, intracellular, and its Aspergillus niger homologue that is extracellular. In both, a heterologous signal peptide for secretion was also included at the N-terminus of the recombinant proteins. One of the hybrid proteins obtained has interesting properties for its biotechnological utilization. Results The highest levels of intracellular and extracellular β-galactosidase were obtained when the segment corresponding to the five domain of K. lactis β-galactosidase was replaced by the corresponding five domain of the A. niger β-galactosidase. Taking into account that this replacement may affect other parameters related to the activity or the stability of the hybrid protein, a thoroughly study was performed. Both pH (6.5 and temperature (40°C for optimum activity differ from values obtained with the native proteins. The stability was higher than the corresponding to the β-galactosidase of K. lactis and, unlike this, the activity of the hybrid protein was increased by the presence

  7. Production and action pattern of inulinase from Aspergillus Niger-245: hydrolysis of inulin from several sources Produção e mecanismo de ação de inulinase de Aspergillus niger-245: hidrólise de inulinas de diferentes origens

    OpenAIRE

    Vinícius D’Arcadia Cruz; Juliana Gisele Belote; Márcia Zilioli Belline; Rubens Cruz

    1998-01-01

    A strain of Aspergillus niger isolated from soil samples showed great capacity to produce extracellular inulinase. Although the enzyme has been synthesized in presence of monosaccharides, sucrose and sugar cane molasse, the productivity was significantly higher (p

  8. The opposite roles of agdA and glaA on citric acid production in Aspergillus niger.

    Science.gov (United States)

    Wang, Lu; Cao, Zhanglei; Hou, Li; Yin, Liuhua; Wang, Dawei; Gao, Qiang; Wu, Zhenqiang; Wang, Depei

    2016-07-01

    Citric acid is produced by an industrial-scale process of fermentation using Aspergillus niger as a microbial cell factory. However, citric acid production was hindered by the non-fermentable isomaltose and insufficient saccharification ability in A. niger when liquefied corn starch was used as a raw material. In this study, A. niger TNA 101ΔagdA was constructed by deletion of the α-glucosidase-encoding agdA gene in A. niger CGMCC 10142 genome using Agrobacterium tumefaciens-mediated transformation. The transformants A. niger OG 1, OG 17, and OG 31 then underwent overexpression of glucoamylase in A. niger TNA 101ΔagdA. The results showed that the α-glucosidase activity of TNA 101ΔagdA was decreased by 62.5 % compared with CGMCC 10142, and isomaltose was almost undetectable in the fermentation broth. The glucoamylase activity of the transformants OG 1 and OG 17 increased by 34.5 and 16.89 % compared with that of TNA 101ΔagdA, respectively. In addition, for the recombinants TNA 101ΔagdA, OG 1 and OG 17, there were no apparent defects in the growth development. Consequently, in comparison with CGMCC 10142, TNA 101ΔagdA and OG 1 decreased the residual reducing sugar by 52.95 and 88.24 %, respectively, and correspondingly increased citric acid production at the end of fermentation by 8.68 and 16.87 %. Citric acid production was further improved by decreasing the non-fermentable residual sugar and increasing utilization rate of corn starch material in A. niger. Besides, the successive saccharification and citric acid fermentation processes were successfully integrated into one step. PMID:26837219

  9. SYNERGISTIC ACTIVITY OF ENZYMES PRODUCED BY EUPENICILLIUM JAVANICUM AND ASPERGILLUS NIGER NRRL 337 ON PALM OIL FACTORY WASTES

    Directory of Open Access Journals (Sweden)

    TRESNAWATI PURWADARIA

    2003-01-01

    Full Text Available The use of palm kernel cake (PKC and palm oil mill effluent (POME, substances from palm oil factory wastes, for monogastric is limited by their high cellulose and mannan contents. Hydrolytic enzymes have been supplemented to increase the nutrient digestibility. The maximal digestibility was obtained in the synergistic action of all enzyme components including B-D-endoglucanase (CMCase, B-D-glucosidase, B-D-mannanase, p-D-mannosidase, and oc-D-galactosidase. Two kinds of enzymes produced by Eupenicillium javanicum and Aspergillus niger NRRL 337 on the submerged culture containing 3% coconut meal were selected to hydrolyze PKC or dry POME. Enzyme from E. javanicum contained higher CMCase, B-D-mannanase, and a-D- galactosidase activities, while that from A. niger NRRL 337 contained more p-D-glucosidase and p-D-mannosidase activities. Saccharification (hydrolytic activities of enzyme mixtures on PKC and POME were determined at pH 5.0, the optimal pH for p-D-mannanase from E. javanicum, and at 5.4 the optimal pH for a-D-galactosidase from E. javanicum and P-D-glucosidase from A. niger NRRL 337. The enzyme proportions of E. javanicum and A. niger NRRL 337 were 100 : 0, 80 : 20, 60 : 40, 40 : 60, and 0 : 100%. The highest Saccharification activity on both substrates was observed on the mixture of 80% A. niger NRRL 337. The pH levels did not significantly affect Saccharification activity. Fiber components in PKC were more digestable than in POME. Further analysis on the reducing sugar components using thin layer chromatography showed that more monomers were produced in the 60 or 80% of A. niger NRRL 337. The glycosidases of A. niger NRRL 337 played more important role in the Saccharification activity.

  10. Niger

    DEFF Research Database (Denmark)

    Hahonou, Eric Komlavi

    2015-01-01

    The chapter provides knowledge about the role of non-state actors in security provision in Niger. It argues that it is of upmost importance to dig into the causes of ongoing armed conflicts and volatile situations. It points out the long-term decline of public service provision (including the role...

  11. Characterization And Application Of Tannase Produced By Aspergillus Niger ITCC 6514.07 On Pomegranate Rind

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    Anita Srivastava

    2009-12-01

    Full Text Available Extracellular tannase and gallic acid were produced optimally under submerged fermentation at 37 0C, 72 h, pH 5.0, 10 %(v/v inoculum and 4 %(w/v of the agroresidue pomegranate rind (PR powder by an Aspergillus niger isolate. Tannic acid (1 % stimulated the enzyme production by 245.9 % while with 0.5 % glucose, increase was marginal. Tannase production was inhibited by gallic acid and nitrogen sources such as NH4NO3, NH4Cl, KNO3, asparatic acid, urea and EDTA. The partially purified enzyme showed temperature and pH optima of 35 0C and 6.2 respectively which shifted to 40 0C and 5.8 on immobilization in alginate beads. Activity of the enzyme was inhibited by Zn+2, Ca+, Mn+2, Mg+2, Ba+2and Ag+. The immobilized enzyme removed 68.8 % tannin from juice of aonla/myrobalan (Phyllanthus emblica, a tropical fruit, rich in vitamin C and other essential nutrients. The enzymatic treatment of the juice with minimum reduction in vitamin C is encouraging as non enzymatic treatments of myrobalan juice results in vitamin C removal.

  12. Microalgae Harvest through Fungal Pelletization—Co-Culture of Chlorella vulgaris and Aspergillus niger

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    Sarman Oktovianus Gultom

    2014-07-01

    Full Text Available Microalgae harvesting is a labor- and energy-intensive process and new approaches to harvesting microalgae need to be developed in order to decrease the costs. In this study; co-cultivatation of filamentous fungus (Aspergillus niger and microalgae (Chlorella vulgaris to form cell pellets was evaluated under different conditions, including organic carbon source (glucose; glycerol; and sodium acetate concentration; initial concentration of fungal spores and microalgal cells and light. Results showed that 2 g/L of glucose with a 1:300 ratio of fungi to microalgae provided the best culturing conditions for the process to reach >90% of cell harvest efficiency. The results also showed that an organic carbon source was required to sustain the growth of fungi and form the cell pellets. The microalgae/fungi co-cultures at mixotrophic conditions obtained much higher total biomass than pure cultures of each individual strains; indicating the symbiotic relationship between two strains. This can benefit the microbial biofuel production in terms of cell harvest and biomass production.

  13. Removal of cadmium and zinc ions from aqueous solution by living Aspergillus niger

    Institute of Scientific and Technical Information of China (English)

    LIU Yun-guo; FAN Ting; ZENG Guang-ming; LI Xin; TONG Qing; YE Fei; ZHOU Ming; XU Wei-hua; HUANG Yu-e

    2006-01-01

    The potential of living Aspergillus niger to remove cadmium and zinc from aqueous solution was investigated. Effects of pH, initial concentration, contact time, temperature and agitation rate on the biosorption of Cd(Ⅱ) and Zn(Ⅱ) ions were studied. The optimum adsorption pH value for Cd(Ⅱ) and Zn(Ⅱ) were 4.0 and 6.0. The best temperature and agitation rate were in the range of 25-30 ℃ and 120 r/min for all metal ions. Under the optimal conditions, the maximum uptake capacities of Cd(Ⅱ) and Zn( Ⅱ ) ions are 15.50 mg/g and 23.70 mg/g at initial concentrations of 75 mg/L and 150 mg/L, respectively. Biosorption equilibrium is established within 24 h for cadmium and zinc ions. The adsorption data provide an excellent fit to Langmuir isotherm model. The results of the kinetic studies show that the rate of adsorption follows the pseudo-second order kinetics.

  14. Metabolic activity in dormant conidia of Aspergillus niger and developmental changes during conidial outgrowth.

    Science.gov (United States)

    Novodvorska, Michaela; Stratford, Malcolm; Blythe, Martin J; Wilson, Raymond; Beniston, Richard G; Archer, David B

    2016-09-01

    The early stages of development of Aspergillus niger conidia during outgrowth were explored by combining genome-wide gene expression analysis (RNAseq), proteomics, Warburg manometry and uptake studies. Resting conidia suspended in water were demonstrated for the first time to be metabolically active as low levels of oxygen uptake and the generation of carbon dioxide were detected, suggesting that low-level respiratory metabolism occurs in conidia for maintenance. Upon triggering of spore germination, generation of CO2 increased dramatically. For a short period, which coincided with mobilisation of the intracellular polyol, trehalose, there was no increase in uptake of O2 indicating that trehalose was metabolised by fermentation. Data from genome-wide mRNA profiling showed the presence of transcripts associated with fermentative and respiratory metabolism in resting conidia. Following triggering of conidial outgrowth, there was a clear switch to respiration after 25min, confirmed by cyanide inhibition. No effect of SHAM, salicylhydroxamic acid, on respiration suggests electron flow via cytochrome c oxidase. Glucose entry into spores was not detectable before 1h after triggering germination. The impact of sorbic acid on germination was examined and we showed that it inhibits glucose uptake. O2 uptake was also inhibited, delaying the onset of respiration and extending the period of fermentation. In conclusion, we show that conidia suspended in water are not completely dormant and that conidial outgrowth involves fermentative metabolism that precedes respiration. PMID:27378203

  15. Microbial leaching of chromite overburden from Sukinda mines, Orissa, India using Aspergillus niger

    Science.gov (United States)

    Biswas, Supratim; Samanta, Saikat; Dey, Rajib; Mukherjee, Siddhartha; Banerjee, Pataki C.

    2013-08-01

    Leaching of nickel and cobalt from two physical grades (S1, 125-190 μm, coarser and S3, 53-75 μm, finer) of chromite overburden was achieved by treating the overburden (2% pulp density) with 21-d culture filtrate of an Aspergillus niger strain grown in sucrose medium. Metal dissolution increases with ore roasting at 600°C and decreasing particle size due to the alteration of microstructural properties involving the conversion of goethite to hematite and the increase in surface area and porosity as evident from X-ray diffraction (XRD), thermogravimetry-differential thermal analysis (DT-TGA), and field emission scanning electron microscopy (FESEM). About 65% Ni and 59% Co were recovered from the roasted S3 ore employing bioleaching against 26.87% Ni and 31.3% Co using an equivalent amount of synthetic oxalic acid under identical conditions. The results suggest that other fungal metabolites in the culture filtrate played a positive role in the bioleaching process, making it an efficient green approach in Ni and Co recovery from lateritic chromite overburden.

  16. The role of initial spore adhesion in pellet and biofilm formation in Aspergillus niger.

    Science.gov (United States)

    Priegnitz, Bert-Ewald; Wargenau, Andreas; Brandt, Ulrike; Rohde, Manfred; Dietrich, Sylvia; Kwade, Arno; Krull, Rainer; Fleissner, André

    2012-01-01

    Fungi grow on a great variety of organic and inorganic materials. Colony establishment and growth on solid surfaces require adhesion of spores and hyphae to the substrate, while cell-to-cell interactions among spores and/or hyphae are a prerequisite for the development of three-dimensional mycelial structures such as pellets or biofilms. Surface adherence has been described as a two-step process, comprised of the initial attachment of ungerminated conidia followed by further adhesion of the forming germ tubes and growing hyphae. In the present study, we analyzed the contribution of adhesion of ungerminated spores to pellet and biofilm formation in Aspergillus niger. Mutants deficient in melanin biosynthesis were constructed by the deletion of the alb1 gene, encoding a polyketide synthase essential for pigment biosynthesis. Δalb1 conidia have an altered surface structure and changed physicochemical surface properties. Spore aggregation in liquid culture as well as spore surface attachment differ between the wild type and the mutant in a pH-dependent manner. In liquid culture further pellet formation is unaffected by altered spore-spore interactions, indicating that germ tube and hyphal adherence can compensate for deficiencies in the initial step of spore attachment. In contrast, under conditions promoting adhesion of Δalb1 conidia to polymer surfaces the mutant forms more stable biofilms than the wild type, suggesting that initial spore adhesion supports sessile growth. PMID:22178638

  17. Cellulase production by Aspergillus niger in biofilm, solid-state, and submerged fermentations.

    Science.gov (United States)

    Gamarra, Norma N; Villena, Gretty K; Gutiérrez-Correa, Marcel

    2010-06-01

    Cellulase production by Aspergillus niger was compared in three different culture systems: biofilm, solid-state, and submerged fermentation. Biofilm and solid-state fermentations were carried out on perlite as inert support, and lactose was used as a carbon source in the three culture systems. In cryo-scanning electron microscopy, biofilm and solid-state cultures gave similar morphological patterns and confirmed that both spore first attachment and hyphal adhered growth are helped by the production of an adhesive extracellular matrix. Biofilm cultures produced higher cellulase activities than those in submerged and solid-state cultures (1,768, 1,165, and 1,174 U l(-1), respectively). Although biofilm cultures grew less than the other cultures, they produced significantly higher cellulase yields (370, 212, and 217 U g(-1) lactose, respectively) and volumetric productivities (24, 16, and 16 U l(-1) h(-1), respectively). Likewise, endoglucanase and xylanase activities were higher in biofilm cultures. Under the conditions tested, it seems that fungal attached growth on perlite may favor better enzyme production. Biofilms are efficient systems for cellulase production and may replace solid-state fermentation. Biofilm fermentation holds promise for further optimization and development. The results of this work reveal that fungal biofilms may be used for the commercial production of cellulase employing the technology developed for submerged fermentation at high cell densities. PMID:20354693

  18. Studies on extracellular biosynthesis of silver nanoparticles by the fungus aspergillus niger

    International Nuclear Information System (INIS)

    An eco-friendly process for the synthesis of silver nanoparticles has been attempted, using the culture filtrate of various microorganisms, included bacteria, fungi and yeast. Only fungi, especially aspergillus niger, were capable of synthesizing silver nanoparticles. The culture filtrate treated with AgNo3 (1 mM) turned dark brown after 72 h of incubation, indicating reduction of silver ions into silver nanoparticles. This observation was confirmed with UV-vis spectroscopy analysis;a large broad band with long tail was detected at 430 nm,this band is characteristic of several metal nanoparticles.X ray diffraction revealed the crystalline nature of obtained nanoparticles. The TEM and SEM analysis showed particles spherical in shape. The average particles size determined by DLS analysis was 94.2 nm.EDX analysis indicated the presence of silver element in the nanoparticles. FT-IR analysis confirmed the presence of protein associated with the synthesized silver nanoparticles. The maximum biosynthesis of nanoparticles was achieved when the culture filtrate was treated with 4.0 mM of AgNo3, adjusted to ph 8.0, and incubated at 50 degree C for 96 h. Silver nanoparticles showed antibiotic activity exceeding that of silver ions against various microorganisms

  19. Chemical modification of Aspergillus nigerβ-glucosidase and its catalytic properties

    Directory of Open Access Journals (Sweden)

    Samia A. Ahmed

    2015-03-01

    Full Text Available Aspergillus niger β-glucosidase was modified by covalent coupling to periodate activated polysaccharides (glycosylation. The conjugated enzyme to activated starch showed the highest specific activity (128.5 U/mg protein. Compared to the native enzyme, the conjugated form exhibited: a higher optimal reaction temperature, a lower Ea (activation energy, a higher Km (Michaelis constant and Vmax (maximal reaction rate, and improved thermal stability. The calculated t1/2 (half-life values of heat in-activation at 60 °C and 70 °C were 245.7 and 54.5 min respectively, whereas at these temperatures the native enzyme was less stable (t1/2of 200.0 and 49.5 min respectively. The conjugated enzyme retained 32.3 and 29.7%, respectively from its initial activity in presence of 5 mM Sodium Dodecyl Sulphate (SDS and p-Chloro Mercuri Benzoate (p-CMB, while the native enzyme showed a remarkable loss of activity (retained activity 1.61 and 13.7%, respectively. The present work has established the potential of glycosylation to enhance the catalytic properties of β-glucosidase enzyme, making this enzyme potentially feasible for biotechnological applications.

  20. Amelioration Of Radiation-Induced Oxidative Stress Using Water Soluble Chitosan Produced By Aspergillus Niger

    International Nuclear Information System (INIS)

    Chitosan is a natural polysaccharide synthesized by a great number of living organisms and considered as a source of potential bioactive material and has many biological applications which are greatly affected by its solubility in neutral ph. In this study, low molecular weight water soluble chitosan was prepared by chemical degradation of chitosan produced by Aspergillus niger using H2O2. Chitosan chemical structure was detected before and after treatment using FTIR spectrum, and its molecular weight was determined by its viscosity using viscometer. Its antioxidant activity against gamma radiation was evaluated in vivo using rats. Rats were divided into 4 groups; group 1: control, group 2: exposed to acute dose of gamma radiation (6 Gy), group 3: received water soluble chitosan, group 4: received water soluble chitosan then exposed to gamma radiation as group 2. Gamma radiation significantly increased malondialdehyde, decreased glutathione, superoxide dismutase, catalase and glutatione peroxidase, while significantly increased alanine transferase, aspartate transferase, urea and creatinine levels. Administration of water soluble chitosan has ameliorated induced changes caused by gamma radiation. It could be concluded that water soluble chitosan by scavenging free radicals directly or indirectly may act as a potent radioprotector against ionizing irradiation

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

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    Georgi Todorov Dobrev

    2012-03-01

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

  2. Amelioration of radiation induced oxidative stress using water soluble chitosan produced by Aspergillus niger

    International Nuclear Information System (INIS)

    Chitosan is a natural polysaccharide synthesized by a great number of living organisms and considered as a source of potential bioactive material and has many biological applications which are greatly affected by its solubility in neutral ph. In this study low molecular weight water soluble chitosan was prepared by chemical degradation of chitosan produced by Aspergillus niger using H2O2. Chitosan chemical structure was detected before and after treatment using FTIR spectrum, and its molecular weight was determined by its viscosity using viscometer. Its antioxidant activity against gamma radiation was evaluated in vivo using rats. Rats were divided into 4 groups; group 1: control, group 2: exposed to acute dose of gamma radiation (6 Gy), group 3: received water soluble chitosan, group 4: received water soluble chitosan then exposed to gamma radiation as group 2. Gamma radiation significantly increased malonaldehyde, decreased glutathione concentration, activity of superoxide dismutase, catalase, and glutatione peroxidase, while significantly increase the activity of alanine transferase, aspartate transferase, urea and creatinine concentration. Administration of water soluble chitosan has ameliorated induced changes caused by gamma radiation. It could be concluded that water soluble chitosan by scavenging free radicals directly or indirectly may act as a potent radioprotector against ionizing irradiation.

  3. Expression and characterization of a cutinase (AnCUT2 from Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Ahmed Al-Tammar Khadijah

    2016-03-01

    Full Text Available Cutin hydrolase (EC 3.1.1.74, an extracellular polyesterase found in pollens, bacteria and fungi, is an efficient catalyst that exhibits hydrolytic activity on a variety of water-soluble esters, synthetic fibers, plastics and triglycerides. Thus, cutinase can be used in various applications such as ester synthesis, bio-scouring, food and detergent industries. Ancut2 is one of five genes encoding cutinases present in the Aspergillus niger ATCC 10574 genome. The cDNA of Ancut2 comprising of an open reading frame of 816 bp encoding a protein of 271 amino acid residues, was isolated and expressed in Pichia pastoris. The partially purified recombinant cutinase exhibited a molecular mass of approximately 40 kDa. The enzyme showed highest activity at 40°C with a preference for acidic pH (5.0-6.0. AnCUT2 showed hydrolytic activity towards various p-nitrophenyl esters with preference towards shorter chain esters such as p-nitrophenyl butyrate (C4. Scanning Electron Microscopy demonstrated that AnCUT2 was capable of modifying surfaces of synthetic polycaprolactone and polyethylene terephthalate plastics. The properties of this enzyme suggest that it may be applied in synthetic fiber modification and fruit processing industries.

  4. Optimization of substrate concentration for enhanced citric acid production by aspergillus niger M-101

    International Nuclear Information System (INIS)

    Studying the effect of different sugar concentration of beet molasses on citric acid accumulation in batch fermentation, 150 g/litre sugar concentration was found to be optimal for maximum citric acid production (27.25+-2.35 g/litre) using Aspergillus niger M-101. Y/sup p/x/ value for product formation increased with increase in sugar concentration through out the study. Qp value for citric acid production also increased with increase in sugar concentration and reached the maximum (0.141 g/litre/h) at 150 g/litre sugar concentration but with further increase in sugar concentration, the value decreased. When culture was grown at different substrate concentrations, the kinetic parameters monitored for Y/sub x/s/, Y/sub p/s/ and Y/sub p/x/, Q/sub p/, Q/sub s/ and q/sub p/ showed significant enhancement (p <= 0.05) in citric acid production as well as biomass growth. (author)

  5. Continuous production of cheese by immobilized milk-clotting protease from aspergillus niger MC4

    Science.gov (United States)

    Channe; Shewale

    1998-11-01

    Milk clotting protease from Aspergillus niger MC4 immobilized on glycidyl methacrylate-pentaerythritol triacrylate copolymer GP4 was used for continuous production of cheese using a packed bed reactor. Factors affecting the hydrolysis of kappa-casein and clot formation were studied. Acidified milk (pH 5.8) preincubated at 37 degreesC when passed through the column at a flow rate of 80 mL/min attained the required degree of hydrolysis of kappa-casein for the coagulation in a single pass. Fortification of the hydrolyzed milk with CaCl2 and FeCl3 to a final concentration of 0.01 and 0.02 M, respectively, and incubation of fortified milk at 60 degreesC for 2 h resulted in a hard cake of cheese. The yield of raw cheese was 28 g/100 mL of milk. The immobilized milk-clotting protease was used for 60 days (8 h/day) without any loss in productivity. PMID:9841651

  6. Xylanase production by a local fungal isolate, Aspergillus niger USM AI 1 via solid state

    Directory of Open Access Journals (Sweden)

    Ibrahim Che Omar

    2005-03-01

    Full Text Available Isolate USM A1 I which was identified to be Aspergillus niger was selected as a potential producer of xylanase via a solid state fermentation system (SSF using palm kernel cake (PKC as substrate. The modification of the physical conditions of the SSF system indicated that the xylanase activity was 23.97 U/g PKC at the moisture ratio of 1:0.75 of PKC: moistening agent with the inoculum size of 1¥104 spores/ml and cultivated at the ambient temperature (28±3ºC. The supplementation of additional carbon and nitrogen sources in the PKC medium could enhance enzyme productivity. The maximum production of xylanase and growth obtained with the supplementation of xylose at 0.75% (w/w were 25.40 U/g and 1.69 mg glucosamine/ g PKC. Moreover, the presence of NaNO3 at 0.075% (w/w as additional nitrogen source further enhanced xylanase production to 33.99 U/g PKC although the growth remained unchanged at about 1.67 mg glucosa- mine/g PKC. The optimized conditions showed an increased xylanase production by 157% compared to before the optimization of the SSF system. The xylanase productivity was 23.12 U/mg glucosamine after optimization and 11.72 U/mg glucosamine before optimization.

  7. Biodiesel Production by Aspergillus niger Lipase Immobilized on Barium Ferrite Magnetic Nanoparticles

    Directory of Open Access Journals (Sweden)

    Ahmed I. El-Batal

    2016-05-01

    Full Text Available In this study, Aspergillus niger ADM110 fungi was gamma irradiated to produce lipase enzyme and then immobilized onto magnetic barium ferrite nanoparticles (BFN for biodiesel production. BFN were prepared by the citrate sol-gel auto-combustion method and characterized by transmission electron microscopy (TEM, X-ray diffraction (XRD, Fourier transform infrared (FTIR and scanning electron microscopy with energy dispersive analysis of X-ray (SEM/EDAX analysis. The activities of free and immobilized lipase were measured at various pH and temperature values. The results indicate that BFN–Lipase (5% can be reused in biodiesel production without any treatment with 17% loss of activity after five cycles and 66% loss in activity in the sixth cycle. The optimum reaction conditions for biodiesel production from waste cooking oil (WCO using lipase immobilized onto BFN as a catalyst were 45 °C, 4 h and 400 rpm. Acid values of WCO and fatty acid methyl esters (FAMEs were 1.90 and 0.182 (mg KOH/g oil, respectively. The measured flash point, calorific value and cetane number were 188 °C, 43.1 MJ/Kg and 59.5, respectively. The cloud point (−3 °C, pour point (−9 °C, water content (0.091% and sulfur content (0.050%, were estimated as well.

  8. [Study of the topology of the active center of glycosidases of Aspergillus niger].

    Science.gov (United States)

    Borzova, N V; Varbanets', L D

    2004-01-01

    Activity of alpha-N-acetylgalactosaminidase and alpha-galactosidase isolated from the culture medium of micromycete Aspergillus niger v. Tiegh F-16694 has been studied as affected by anions, cations and specific chemical reagents (n-chlormercurybenzoate, L-cysteine, dithiotreitol, beta-mercaptoethanol, EDTA, o-phenanthroline, sodium azide, hydrogen peroxide). It has been established that silver ions noncompetitively inhibit alpha-galactosidase at pH 5.2, the inhibition constant (Ki) being 2.5 x 10(-4) M. Galactose in concentration of 1-5 mM does not protect the enzyme from the negative action of silver ions, but this inhibitory effect is almost completely removed by the corresponding concentrations of L-cysteine. The same noncompetitive character was inherent in the inhibition of alpha-galactosidase reaction by mercury ions and n-chlormercurybenzoat (Ki is 4.5 x 10(-6) and 1.8 x 10(-4), respectively). The importance of sulphydryl groups for the support of active comformation of alpha-galactosidase molecule was established on the basis of inhibition and kinetic analysis. It has been shown that the enzyme molecule does not contain the groups which include metal atoms. PMID:15554293

  9. Induction, purification and characterization of alpha-N-acetylgalactosaminidase from Aspergillus Niger.

    Science.gov (United States)

    Weignerová, L; Filipi, T; Manglová, D; Kren, V

    2008-07-01

    A set of filamentous fungi (42 strains) was screened for alpha-N-acetylgalactosaminidase activity, and a series of inducers and different cultivation conditions were tested. Enzyme production by the best producer Aspergillus niger CCIM K2 was optimized and scaled up. alpha-N-Acetylgalactosaminidase was purified to apparent homogeneity by cation exchange chromatography, gel filtration, and chromatofocusing, and basic biochemical data of the enzyme were determined: The native molecular weight was estimated by gel filtration to be approximately 440 kDa, the molecular weight of the subunit was determined to be 76 kDa and the pI = 4.8. The K (M) was 0.73 mmol/l for o-nitrophenyl 2-acetamido-2-deoxy-alpha-D-galactopyranoside (o-NP-alpha-GalNAc), and optimum enzyme activity was achieved at pH 1.8 and 55 degrees C. This alpha-N-acetylgalactosaminidase is a retaining-type glycosidase, and it was N-deglycosylated without any loss of activity. PMID:18443780

  10. Improving the extraction conditions of endoglucanase produced by Aspergillus niger under solid-state fermentation

    Directory of Open Access Journals (Sweden)

    R. D. P. B. Pirota

    2013-03-01

    Full Text Available Production of cellulases under solid-state fermentation (SSF is a promising technique that can help to reduce costs. Besides optimizing the production process, it is also important to consider enzyme recovery during the extraction step. Here, an experimental design methodology was used to investigate the effects of the operational parameters solid to liquid ratio (1:3, 1:6 and 1:9, stirring rate (80, 120 and 160 rpm, and temperature (10, 22 and 35 °C on the recovery of endoglucanases produced by Aspergillus niger cultivated under SSF. Statistical analysis revealed that only the solid to liquid ratio had a significant influence on endoglucanase extraction. The highest endoglucanase recovery (35.7 U/g was achieved using 0.2 mol/L acetate buffer at pH 4.8, together with a solid to liquid ratio of 1:9 and an agitation time of 10 minutes. In sequential extraction experiments, it was shown that most of the enzyme was recovered during the first extraction. The procedure adopted increased the efficiency of endoglucanase extraction by 70%, emphasizing the importance of selection of suitable operational conditions during SSF processes.

  11. Isotherm studies for determination of removal capacity of bi-metal (Ni and Cr) ions by aspergillus niger

    International Nuclear Information System (INIS)

    Pakistan is among the developing countries where there is a need to establish new industries to meet the demands of a growing population. This has led to industrial setup in various sectors, without proper planning and consideration for treatment of contamination, leading to disposal of untreated wastewater into nearby land and water bodies. This study was planned to investigate an indigenous Aspergillus niger for development of biosorbent for the removal of metal ions. The Aspergillus isolate's Ni and Cr removal efficiency was determined in batch mode over various pH (4.0-10.0) and temperature (25-40 deg. C) as single as well as bimetal ions. Using a single metal ion, maximum biosorption potential was obtained at pH 5.0-6.0 and 30-35 deg. C for both ions. On the other hand, Ni removal was reduced in the presence of Cr, while Ni removal influenced Cr removal with an increase showing maximum removal at an initial adsorbate concentration of 50mg/L, pH 6.0 and 35 deg. C. Effect of presence of bimetal in a solution on biosorption potential of Aspergillus niger was predicted by using equilibrium modeling. Adsorption trends for both nickel (R2 0.9916) and chromium (R2 0.8548) followed Langmuir isotherm in single metal removal system, but under bimetal condition chromium adsorption fitted better to Freundlich model and that of nickel followed Temkin isotherm, suggesting considerable change in behavior and interaction between biosorbent and metal ions. Therefore, we concluded that Aspergillus niger a viable strain for development of a biosorbent for removal of a mixture of metal ions. (author)

  12. Aspergillus niger PA2: a novel strain for extracellular biotransformation of L-tyrosine into L-DOPA.

    Science.gov (United States)

    Agarwal, Pragati; Pareek, Nidhi; Dubey, Swati; Singh, Jyoti; Singh, R P

    2016-05-01

    L-DOPA (3,4-dihydroxyphenyl-L-alanine), an amino acid derivative is the most widely used drug of choice for the treatment of Parkinson's disease and other neurologic injuries. The present study deals with the elevated biochemical transformation of L-tyrosine to L-DOPA by Aspergillus niger PA2, a potent tyrosinase producer, isolated from decomposed food wastes. This appears to be the first report on A. niger as a notable extracellular tyrosinase producer. The extracellular tyrosinase activity produced remarkably higher levels of L-DOPA, i.e. 2.44 mg mL(-1) when the media was supplemented with 5 mg mL(-1) L-tyrosine. The optimum pH for tyrosinase production was 6.0, with the maximal L-DOPA production at the same pH. The product thus produced was analyzed by thin-layer chromatography, UV spectroscopy, high-performance liquid chromatography and Fourier transform infrared spectroscopy, that had denoted this to be L-DOPA. Kinetic parameters viz. Y p/s, Q s and Q p had further indicated the notable levels of production. Thus, Aspergillus niger PA2 could be a promising resource and may be further exploited for large-scale production of L-DOPA. PMID:26781225

  13. Produção de celulases por Aspergillus niger e cinética da desativação celulásica=Cellulases production by Aspergillus niger and cellulase deactivation kinetic

    OpenAIRE

    Caroline Mariana de Aguiar; Sérgio Luiz de Lucena

    2011-01-01

    O presente trabalho teve como objetivo a avaliação da cinética de produção de enzimas celulases pelo fungo Aspergillus niger e da cinética de desativação das celulases. Foi utilizado bagaço de cana-de-açúcar pré-tratado como fonte de carbono na fermentação para a produção do complexo celulásico e também como substrato da hidrólise enzimática. A. niger foi cultivado em três bateladas, cada uma contendo 10, 50 e 100 g L-1 de bagaço pré-tratado com NaOH 4% (m v-1). A cinética da produção das cel...

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

    DEFF Research Database (Denmark)

    Mogensen, Jesper Mølgaard; Nielsen, Kristian Fog; Samson, Robert A.;

    2009-01-01

    Background Fumonisins are economically important mycotoxins which until recently were considered to originate from only a few Fusarium species. However recently a putative fumonisin gene cluster was discovered in two different Aspergillus niger strains followed by detection of an actual fumonisin B...... fumonisin B1 and other isoforms (fumonisin B2 and B3). Five A. niger and five Fusarium spp. were incubated at six different temperatures from 15-42°C on Czapek Yeast Agar +5% salt or Potato Dextrose Agar. A. niger had the highest production of FB2 at 25-30°C whereas Fusarium spp. had the maximal production...... of FB1 and FB2 at 20-25°C. Addition of 2.5-5% NaCl, or 10-20% sucrose increased the FB2 production of A. niger, whereas addition of glycerol reduced FB2 production. All three water activity lowering solutes reduced the fumonisin production of the Fusarium species. Conclusion The present study shows...

  15. Highly thermostable and pH-stable cellulases from Aspergillus niger NS-2: properties and application for cellulose hydrolysis.

    Science.gov (United States)

    Bansal, Namita; Janveja, Chetna; Tewari, Rupinder; Soni, Raman; Soni, Sanjeev Kumar

    2014-01-01

    Optimization of cultural conditions for enhanced cellulase production by Aspergillus niger NS-2 were studied under solid-state fermentation. Significant increase in yields (CMCase 463.9 ± 20.1 U/g, FPase 101.1 ± 3.5 U/g and β-glucosidase 99 ± 4.0 U/g) were obtained under optimized conditions. Effect of different nutritional parameters was studied to induce the maximum production of cellulase complex. Scale-up studies for enzyme production process were carried out. Characterization studies showed that enzymes produced by A. niger NS-2 were highly temperature- and pH stable. At 50 °C, the half life for CMCase, FPase, β-glucosidase were approximately 240 h. Cellulases from A. niger NS-2 were stable at 35 °C for 24 h over a broader pH range of 3.0-9.0. We examined the feasibility of using steam pretreatment to increase the saccharification yields from various lignocellulosic residues for sugar release which can potentially be used in bioethanol production. Saccharification of pretreated dry potato peels, carrot peels, composite waste mixture, orange peels, onion peels, banana peels, pineapple peels by crude enzyme extract from A. niger NS-2, resulted in very high cellulose conversion efficiencies of 92-98 %. PMID:24052336

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

    International Nuclear Information System (INIS)

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

  17. Structural analysis of biofilms and pellets of Aspergillus niger by confocal laser scanning microscopy and cryo scanning electron microscopy.

    Science.gov (United States)

    Villena, G K; Fujikawa, T; Tsuyumu, S; Gutiérrez-Correa, M

    2010-03-01

    Biomass organization of Aspergillus niger biofilms and pellets stained with fluorescein isothiocyanate were analyzed by means of confocal laser scanning microscopy and detectable differences between both types of growth were found. Three-dimensional surface plot analysis of biofilm structure revealed interstitial voids and vertical growth compared with pellets. Growth was lower in biofilm and according to fluorescence profile obtained, biomass density increased at the surface (0-20 microm). However, a decrease in fluorescence intensity was observed through optical sections of pellets even though growth was significantly higher than biofilms. Cryo scanning electron microscopy also showed structural differences. While biofilms showed a spatially ordered mycelium and well structured hyphal channels, pellets were characterized by an entangled and notoriously compacted mycelium. These findings revealed common structural characteristics between A. niger biofilms and those found in other microbial biofilms. Thus, biofilm microstructure may represent a key determinant of biofilm growth and physiology of filamentous fungi. PMID:19919894

  18. ETUDE DE L'APTITUDE FROMAGERE D'UN EXTRAIT ENZYMATIQUE COAGULANT PRODUIT PAR ASPERGILLUS NIGER FFB1

    Directory of Open Access Journals (Sweden)

    S. BENSMAIL

    2013-02-01

    Full Text Available After solid - state fermentation on wheat bran under optimum conditions of production, the acid protease ofAspergillus niger FFB1 extracted with sterile distilledwater (1:5 w/v presented milk-clotting activity of 600 SU/g bran and a ratio of coagulant to proteolytic activities 4.7; was applied in the production of unripened cheese pressed using cow milk.Cheese yields obtained by the commercial preparation(control on the one hand and the milk - curdling enzyme of A. niger FFB1 on the other hand; differ by 2.8% of product weight, which are higher in the case of commercial rennet.This difference results from a loss more or less important proteins(11% and fat(4% during the draining, induced by the proteolytic activity of the fungal enzyme extract.The organoleptic qualities of the two hard cheeses produced are very similar.

  19. Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of variants of monoamine oxidase from Aspergillus niger

    International Nuclear Information System (INIS)

    Crystals of A. niger monoamine oxidase variants display P21 or P41212/P43212 symmetry, with eight or two molecules in the asymmetric unit, respectively. Monoamine oxidase from Aspergillus niger (MAO-N) is an FAD-dependent enzyme that catalyses the conversion of terminal amines to their corresponding aldehydes. Variants of MAO-N produced by directed evolution have been shown to possess altered substrate specificity. Crystals of two of these variants (MAO-N-3 and MAO-N-5) have been obtained; the former displays P21 symmetry with eight molecules per asymmetric unit and the latter has P41212 or P43212 symmetry and two molecules per asymmetric unit. Solution of these structures will help shed light on the molecular determinants of improved activity and high enantioselectivity towards a broad range of substrates

  20. Improvement of Aspergillus niger 55, a raw corn meal saccharifying enzyme hyperproducer, through mutation and selective screening techniques

    International Nuclear Information System (INIS)

    Mutation experiments were performed to select the mutant of Aspergillus niger 55, which had lost almost all the ability to produce transglucosidases but retained that of high productivity of raw meal saccharifying enzyme, by means of successive induction with N-methyl-N'-nitro-N-nitrosoguanidine(MNNG), ultraviolet(UV) light, and γ-rays. Also, we used the mutant enrichment techniques, such as liquid culture-filtration procedure and differential heat sensitivity of conidia, in order to increase the possibility of obtaining a mutant. The glucoamylase productivity of mutant PFST-38 was 11 times higher than that of the parent strain. The mutant PFST-38 was morphologically identical to the parent strain, except for the size of conidia, the tendency to form conidia and the length of conidiophore. Asp. niger mutant PFST-38 appeared to be useful for the submerged production of the raw corn meal saccharifying enzyme

  1. Increase of fungitoxicity of mercuric chloride by methionine, ethionine and S-methylcysteine. [Aspergillus niger; Cladosporium cucumerinum; Scopulariopsis brevicaulis

    Energy Technology Data Exchange (ETDEWEB)

    Vonk, J.W.; Sijpesteijn, A.K.

    1974-01-01

    The fungitoxicity of mercuric chloride to Aspergillus niger was increased in the presence of D-, L-, DL-methionine, DL-ethionine, DL-S-methylcysteine or sodium methylmercaptide. The same effect was observed with methionine for two other fungi investigated: Cladosporium cucumerinum and Scopulariopsis brevicaulis. It is suggested that this effect can be ascribed to the formation of CH/sub 3/SHg/sup +/ or (CH/sub 3/S)/sub 2/Hg, or the corresponding ethyl compounds. CH/sub 3/SHgCl and (CH/sub 3/S)/sub 2/Hg were synthetically prepared and proved indeed far more fungitoxic than HgCl/sub 2/. The hypothesis was further substantiated by the observation that A. niger rapidly converts DL-methionine into CH/sub 3/SH, which undoubtedly reacts with Hg/sup 2 +/ to give the above mentioned methylthiomercury compounds. 16 references, 2 figures, 2 tables.

  2. Improvement of xylanase production by Aspergillus niger XY-1 using response surface methodology for optimizing the medium composition

    Institute of Scientific and Technical Information of China (English)

    Yao-xing XU; Yan-li LI; Shao-chun XU; Yong LIU; Xin WANG; Jiang-wu TANG

    2008-01-01

    Objective: To study the optimal medium composition for xylanase production by Aspergillus niger XY-1 in solid-state fermentation (SSF). Methods: Statistical methodology including the Plackett-Burman design (PBD) and the central composite design (CCD) was employed to investigate the individual crucial component of the medium that significantly affected the enzyme yield. Results: Firstly, NaNO3, yeast extract, urea, Na2CO3, MgSO4, peptone and (NH4)2SO4 were screened as the significant factors positively affecting the xylanase production by PBD. Secondly, by valuating the nitrogen sources effect, urea was proved to be the most effective and economic nitrogen source for xylanase production and used for further optimization.Finally, the CCD and response surface methodology (RSM) were applied to determine the optimal concentration of each sig-nificant variable, which included urea, Na2CO3 and MgSO4. Subsequently a second-order polynomial was determined by mul-tiple regression analysis. The optimum values of the critical components for maximum xylanase production were obtained as follows: x1 (urea)=0.163 (41.63 g/L), x2 (Na2CO3)=-1.68 (2.64 g/L), x3 (MGSO4)=1.338 (10.68 g/L) and the predicted xylanase value was 14374.6 U/g dry substrate. Using the optimized condition, xylanase production by Aspergillus niger XY-1 after 48 h fermentation reached 14637 U/g dry substrate with wheat bran in the shake flask. Conclusion: By using PBD and CCD, we obtained the optimal composition for xylanase production by Aspergillus niger XY-1 in SSF, and the results of no additional expensive medium and shortened fermentation time for higher xylanase production show the potential for industrial utilization.

  3. In Vitro Evaluation Of Selected Plant Extracts As Biocontrol Agents Against Black Mold Aspergillus Niger Van Tieghem Of Onion Bulbs Allium Cepa L.

    OpenAIRE

    SAIFELDIN A. F. EL-NAGERABI; Awad H. M. Ahmed; ABDULKADIR E. ELSHAFIE

    2015-01-01

    Black mold disease caused by Aspergillus niger V. Tiegh. is the most devastating infection occurs in onions Allium cepa L. under field and store conditions. The use of biocontrol agents is ecofriendly approach for controlling seedborne and soilborne diseases compared to the use of toxic synthetic fungicides. This study has been designed to assess the contamination levels of onion seeds with A. niger and its effect on seed germination and to evaluate the in vitro antifungal activity of Prunus ...

  4. Adsorption of amyloglucosidase from Aspergillus niger NRRL 3122 using ion exchange resin

    Directory of Open Access Journals (Sweden)

    Ana Paula Manera

    2008-10-01

    Full Text Available Amyloglucosidase enzyme was produced by Aspergillus niger NRRL 3122 from solid-state fermentation, using deffated rice bran as substrate. The effects of process parameters (pH, temperature in the equilibrium partition coefficient for the system amyloglucosidase - resin DEAE-cellulose were investigated, aiming at obtaining the optimum conditions for a subsequent purification process. The highest partition coefficients were obtained using 0.025M Tris-HCl buffer, pH 8.0 and 25ºC. The conditions that supplied the highest partition coefficient were specified, the isotherm that better described the amyloglucosidase process of adsorption obtained. It was observed that the adsorption could be well described by Langmuir equation and the values of Qm and Kd estimated at 133.0 U mL-1 and 15.4 U mL-1, respectively. From the adjustment of the kinetic curves using the fourth-order Runge-Kutta algorithm, the adsorption (k1 and desorption (k2 constants were obtained through optimization by the least square procedure, and the values calculated were 2.4x10-3 mL U-1 min-1 for k1 and 0.037 min-1 for k2 .A enzima amiloglicosidase foi produzida por Aspergillus niger NRRL 3122 através de fermentação em estado sólido, tendo como substrato farelo de arroz desengordurado. Os efeitos dos parâmetros de processo (pH e temperatura no coeficiente de partição no equilíbrio, para o sistema amiloglicosidase - resina DEAE-celulose foram investigados, com o objetivo de se obter as melhores condições para um posterior processo de purificação. Os maiores coeficientes de partição foram obtidos usando tampão Tris-HCl 0,025M pH 8,0 e 25°C. Determinadas as condições que forneceram o maior coeficiente de partição obteve-se a isoterma que melhor descrevia o processo de adsorção de amiloglicosidase. Foi verificado que adsorção pode ser bem descrita pela equação de Langmuir e os valores de Qm e Kd foram estimados em 133,0 U mL-1 e 15,4 U mL-1 respectivamente. A

  5. Purification and characterization of β-Fructosidase with inulinase activity from Aspergillus niger - 245

    Directory of Open Access Journals (Sweden)

    Vinícius D'Arcadia Cruz

    1998-01-01

    Full Text Available Aspergillus niger - 245, a strain isolated from soil samples showed good β-fructosidase activity when inoculated in medium formulated with dahlia extract tubers. The enzyme was purified by precipitation in ammonium sulphate and percolated in DEAE-Sephadex A-50 and CM-cellulose columns, witch showed a single peack in all the purification steps, maintaining the I/S ratio between 0.32 to, 0.39. Optimum pH for inulinase activity (I was between 4.0 - 4.5 and for invertase activity (S between 2.5 and 5.0. The optimum temperature was 60O.C for both activities and no loss in activity was observed when it was maintained at this temperature for 30 min. The Km value was 1.44 and 5.0, respectively, for I and S and Vm value 10.48 and 30.55, respectively. The I activity was strongly inhibited by Hg2+ and Ag+ and 2 x 10-3 M of glucose, but not by fructose at the same concentration. The enzyme showed an exo-action mechanism, acting on the inulin of different origins. In assay conditions total hydrolysis of all the frutans was obtained, although it has shown larger activity on the chicory inulin than that one from artichoke Jerusalem and dahlia, in the first 30 min. The obtained results suggested that the enzyme presented good potential for industrial application in the preparing the fructose syrupsAspergillus niger - 245, isolado do solo mostrou boa atividade de b-frutosidase meio formulado com extrato de tubérculos de dahlia. A enzima foi purificada por precipitação em sulfato de amônia e percolada em colunas de DEAE-Sephadex A-50 e CM-celulose, produzindo um único pico em todas as fases de purificação e mantendo a relação I/S entre 0,32 a 0,39. O pH ótimo para a atividade de inulinase (I foi encontrado entre 4,0 - 4.5 e para a atividade de invertase (S em 2,5 e 5,0. A temperatura ótima foi de 60O.C para ambas as atividades e nenhuma perda foi observada quando mantida nesta temperatura por 30 min. Os valores de Km foram de 1,44 e 5

  6. The carbon starvation response of Aspergillus niger during submerged cultivation: Insights from the transcriptome and secretome

    Directory of Open Access Journals (Sweden)

    Nitsche Benjamin M

    2012-08-01

    Full Text Available Abstract Background Filamentous fungi are confronted with changes and limitations of their carbon source during growth in their natural habitats and during industrial applications. To survive life-threatening starvation conditions, carbon from endogenous resources becomes mobilized to fuel maintenance and self-propagation. Key to understand the underlying cellular processes is the system-wide analysis of fungal starvation responses in a temporal and spatial resolution. The knowledge deduced is important for the development of optimized industrial production processes. Results This study describes the physiological, morphological and genome-wide transcriptional changes caused by prolonged carbon starvation during submerged batch cultivation of the filamentous fungus Aspergillus niger. Bioreactor cultivation supported highly reproducible growth conditions and monitoring of physiological parameters. Changes in hyphal growth and morphology were analyzed at distinct cultivation phases using automated image analysis. The Affymetrix GeneChip platform was used to establish genome-wide transcriptional profiles for three selected time points during prolonged carbon starvation. Compared to the exponential growth transcriptome, about 50% (7,292 of all genes displayed differential gene expression during at least one of the starvation time points. Enrichment analysis of Gene Ontology, Pfam domain and KEGG pathway annotations uncovered autophagy and asexual reproduction as major global transcriptional trends. Induced transcription of genes encoding hydrolytic enzymes was accompanied by increased secretion of hydrolases including chitinases, glucanases, proteases and phospholipases as identified by mass spectrometry. Conclusions This study is the first system-wide analysis of the carbon starvation response in a filamentous fungus. Morphological, transcriptomic and secretomic analyses identified key events important for fungal survival and their chronology. The

  7. Isolation of a thermostable acid phytase from Aspergillus niger UFV-1 with strong proteolysis resistance.

    Science.gov (United States)

    Monteiro, Paulo S; Guimarães, Valéria M; de Melo, Ricardo R; de Rezende, Sebastião T

    2015-03-01

    An Aspergillus niger UFV-1 phytase was characterized and made available for industrial application. The enzyme was purified via ultrafiltration followed by acid precipitation, ion exchange and gel filtration chromatography. This protein exhibited a molecular mass of 161 kDa in gel filtration and 81 kDa in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), indicating that it may be a dimer. It presented an optimum temperature of 60 °C and optimum pH of 2.0. The K M for sodium phytate hydrolysis was 30.9 mM, while the k cat and k cat / K M were 1.46 ×10 (5) s (-1) and 4.7 × 10 (6) s (-1) .M (-1) , respectively. The purified phytase exhibited broad specificity on a range of phosphorylated compounds, presenting activity on sodium phytate, p-NPP, 2- naphthylphosphate, 1- naphthylphosphate, ATP, phenyl-phosphate, glucose-6-phosphate, calcium phytate and other substrates. Enzymatic activity was slightly inhibited by Mg (2+) , Cd (2+) , K (+) and Ca (2+) , and it was drastically inhibited by F (-) . The enzyme displayed high thermostability, retaining more than 90% activity at 60 °C during 120 h and displayed a t 1/2 of 94.5 h and 6.2 h at 70 °C and 80 °C, respectively. The enzyme demonstrated strong resistance toward pepsin and trypsin, and it retained more than 90% residual activity for both enzymes after 1 h treatment. Additionally, the enzyme efficiently hydrolyzed phytate in livestock feed, liberating 15.3 μmol phosphate/mL after 2.5 h of treatment. PMID:26221114

  8. Application of kaolin to improve citric acid production by a thermophilic Aspergillus niger.

    Science.gov (United States)

    Ali, Sikander

    2006-12-01

    Citric acid production by a thermophilic strain of the filamentous fungus Aspergillus niger IIB-6 in a medium containing blackstrap cane molasses was improved by the addition of kaolin to the fermentation medium. The fermentation was run in a 7.5-l stirred bioreactor (60% working volume). The optimal sugar concentration was found to be 150 g/l. Kaolin (1.0 ml) was added to the fermentation medium to enhance volumetric production. The best results in terms of product formation were observed when 15 parts per million (ppm) kaolin was added 24 h after inoculation. With added kaolin, citric acid production was enhanced 2.34-fold, compared to a control fermentation without added kaolin. The length of incubation to attain this product yield was shortened from 168 to 96 h. The comparison of kinetic parameters showed improved citrate synthase activity of the culture (Y (p/x)=7.046 g/g). When the culture grown at various kaolin concentrations was monitored for Q (p), Q (s), and q (p), there was significant improvement in these variables over the control. Specific production by the culture (q (p)=0.073 g/g cells/h) was improved several fold. The addition of kaolin substantially improved the enthalpy (DeltaH (D)=74.5 kJ/mol) and entropy of activation (DeltaS=-174 J/mol/K) for citric acid production, free energies for transition state formation, and substrate binding for sucrose hydrolysis. The performance of fuzzy logic control of the bioreactor was found to be very promising for an improvement ( approximately 4.2-fold) in the production of citric acid (96.88 g/l), which is of value in commercial applications. PMID:16871375

  9. Control of Acid Phosphatases Expression from Aspergillus niger by Soil Characteristics

    Directory of Open Access Journals (Sweden)

    Ely Nahas

    2015-10-01

    Full Text Available ABSTRACTThis work studied the acid phosphatase (APase activity from culture medium (extracellular, eAPase and mycelial extract (intracellular, iAPase ofAspergillus niger F111. The influence of fungus growth and phosphate concentration of the media on the synthesis and secretion of phosphatase was demonstrated. The effects of pH, substrate concentration and inorganic and organic compounds added to the reaction mixture on APase activity were also studied. Both enzymes were repressed by high concentrations of phosphate. Overexpression of iAPase in relation to eAPase was detected; iAPase activity was 46.1 times higher than eAPase. The maximal activity of eAPase was after 24h of fungus growth and for iAPase was after 96h. Optimal pH and substrate concentrations were 4.5 and 8.0 mM, respectively. Michaelis-Menten constant (Km for the hydrolysis of p-nitrophenyl phosphate was 0.57 mM with Vmax = 14,285.71 U mg-1 mycelium for the iAPase and 0.31 mM with V max = 147.06 U mg-1 mycelium for eAPase. Organic substances had little effect on acid phosphatases when compared with the salts. Both the APases were inhibited by 10 mM KH 2PO4 and 5 mM (NH42MoO4; eAPase was also inhibited by 1 mM CoCl2.

  10. Isolation of a thermostable acid phytase from Aspergillus niger UFV-1 with strong proteolysis resistance

    Directory of Open Access Journals (Sweden)

    Paulo S. Monteiro

    2015-03-01

    Full Text Available An Aspergillus niger UFV-1 phytase was characterized and made available for industrial application. The enzyme was purified via ultrafiltration followed by acid precipitation, ion exchange and gel filtration chromatography. This protein exhibited a molecular mass of 161 kDa in gel filtration and 81 kDa in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE, indicating that it may be a dimer. It presented an optimum temperature of 60 °C and optimum pH of 2.0. The KM for sodium phytate hydrolysis was 30.9 mM, while the kcat and kcat/KM were 1.46 ×105 s−1 and 4.7 × 106s−1.M−1, respectively. The purified phytase exhibited broad specificity on a range of phosphorylated compounds, presenting activity on sodium phytate, p-NPP, 2- naphthylphosphate, 1- naphthylphosphate, ATP, phenyl-phosphate, glucose-6-phosphate, calcium phytate and other substrates. Enzymatic activity was slightly inhibited by Mg2+, Cd2+, K+ and Ca2+, and it was drastically inhibited by F−. The enzyme displayed high thermostability, retaining more than 90% activity at 60 °C during 120 h and displayed a t1/2 of 94.5 h and 6.2 h at 70 °C and 80 °C, respectively. The enzyme demonstrated strong resistance toward pepsin and trypsin, and it retained more than 90% residual activity for both enzymes after 1 h treatment. Additionally, the enzyme efficiently hydrolyzed phytate in livestock feed, liberating 15.3 μmol phosphate/mL after 2.5 h of treatment.

  11. Cloning, expression and characterization of β-xylosidase from Aspergillus niger ASKU28.

    Science.gov (United States)

    Choengpanya, Khuanjarat; Arthornthurasuk, Siriphan; Wattana-amorn, Pakorn; Huang, Wan-Ting; Plengmuankhae, Wandee; Li, Yaw-Kuen; Kongsaeree, Prachumporn T

    2015-11-01

    β-Xylosidases catalyze the breakdown of β-1,4-xylooligosaccharides, which are produced from degradation of xylan by xylanases, to fermentable xylose. Due to their important role in xylan degradation, there is an interest in using these enzymes in biofuel production from lignocellulosic biomass. In this study, the coding sequence of a glycoside hydrolase family 3 β-xylosidase from Aspergillus niger ASKU28 (AnBX) was cloned and expressed in Pichia pastoris as an N-terminal fusion protein with the α-mating factor signal sequence (α-MF) and a poly-histidine tag. The expression level was increased to 5.7 g/l in a fermenter system as a result of optimization of only five codons near the 5' end of the α-MF sequence. The recombinant AnBX was purified to homogeneity through a single-step Phenyl Sepharose chromatography. The enzyme exhibited an optimal activity at 70°C and at pH 4.0-4.5, and a very high kinetic efficiency toward a xyloside substrate. AnBX demonstrated an exo-type activity with retention of the β-configuration, and a synergistic action with xylanase in hydrolysis of beechwood xylan. This study provides comprehensive data on characterization of a glycoside hydrolase family 3 β-xylosidase that have not been determined in any prior investigations. Our results suggested that AnBX may be useful for degradation of lignocellulosic biomass in bioethanol production, pulp bleaching process and beverage industry. PMID:26166179

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

    International Nuclear Information System (INIS)

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

  13. Semi-pilot scale production of citric acid in cane molasses by gamma-ray induced mutants of Aspergillus niger

    International Nuclear Information System (INIS)

    Utilizing cane molasses as substrate, semi-pilot scale production of citric acid was investigated in fermentation trays (40 x 35 cm) with several gamma-ray induced mutants of Aspergillus niger. Of the mutants tested, two were found to have high yield efficiency (14/20, 51.06%; 79/20, 50.35%) of sugar to citric acid. The yield of other mutants (HB3, 10/20, 164/20, 277/30 and 112/40) ranged between 30 to 42%. The prospect of utilizing the high yielding mutants for commercial production of citric acid has been discussed. (author)

  14. PRODUCTION OF LIPASES IN SOLID-STATE FERMENTATION BY Aspergillus niger F7-02 WITH AGRICULTURAL RESIDUES

    OpenAIRE

    Olayinka Quadri Adio; Sarafdeen Olateju Kareem; Michael Bamitale Osho; Adebukola Mobolaji Omemu

    2015-01-01

    In this study mould strains screened and molecularly identified as Aspergillus niger F7-02 was used to produced extracellular lipase in Solid State Fermentation (SSF) process. Different agricultural residues were combined in different ratios as carbon, nitrogen and elemental sources in the solid culture medium. The optimization of the culture medium was carried out for such parameters as incubation time (24 h - 96 h), inoculum concentration (0.5 – 3.0%, w/v), initial moisture content (40 – 70...

  15. Studies on production of single cell protein by Aspergillus niger in solid state fermentation of rice bran

    OpenAIRE

    Anupama; Ravindra Pogaku

    2001-01-01

    An attempt was made to apply the solid state fermentation (SSF) for the production of single cell protein (SCP) using oil free rice bran waste as substrate. A local isolate of Aspergillus niger, was used as protein source for the studies. Total proteins were extracted to estimate the mycelial biomass from the moldy bran. Carbonate-bicarbonate extraction buffer and a pH 10 was found to be most efficient among the buffers used for the extraction of the proteins from the organism. The effect of ...

  16. Application of Plackett-Burman Experimental Design for Lipase Production by Aspergillus niger Using Shea Butter Cake

    OpenAIRE

    Aliyu Salihu; Muntari Bala; Bala, Shuaibu M.

    2013-01-01

    Plackett-Burman design was used to efficiently select important medium components affecting the lipase production by Aspergillus niger using shea butter cake as the main substrate. Out of the eleven medium components screened, six comprising of sucrose, (NH4)2SO4, Na2HPO4, MgSO4, Tween-80, and olive oil were found to contribute positively to the overall lipase production with a maximum production of 3.35 U/g. Influence of tween-80 on lipase production was investigated, and 1.0% (v/w) of tween...

  17. Comparison of glucose oxidases from Penicillium adametzii, Penicillium Funiculosum and Aspergillus Niger in the design of amperometric glucose biosensors.

    Science.gov (United States)

    Ramanavicius, Arunas; Voronovic, Jaroslav; Semashko, Tatiana; Mikhailova, Raisa; Kausaite-Minkstimiene, Asta; Ramanaviciene, Almira

    2014-01-01

    The properties of amperometric glucose biosensors based on three different glucose oxidases and various redox mediators were evaluated. Glucose oxidases (GOx) from Penicillium adametzii, Penicillium funiculosum and Aspergillus niger and artificial redox mediators, such as ferrocene, ferrocenecarboxaldehyde, α-methylferrocene methanol and ferrocenecarboxylic acid, were used for modifying the graphite rod electrode and amperometrical reagent-less glucose detection. The obtained results were compared using N-methylphenazonium methyl sulphate in the solution. Taking into account the experimental kinetic parameters and the stability of the tested enzymatic electrodes, GOx from Penicillium funiculosum proved to be more suitable for glucose biosensor design in comparison with other evaluated enzymes. PMID:25492463

  18. 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

  19. Effects of aspergillus niger inoculum concentration upon the kinetics of starchy wastewater pretreatment in a tanks-in-series bioreactor under transitory conditions

    OpenAIRE

    L. Coulibaly; Agathos, S. N.

    2007-01-01

    This paper discusses the effects of three Aspergillus niger inoculum concentrations (0.12, 2.3 and 3.6 g/l) upon the kinetics of starch pretreatment under aerobic and transitory conditions using a tanks-in-series reactor. A synthetic wastewater containing starch as model polysaccharide was fed into the reactor system to study this polymer transformation by Aspergillus niger. Starch and metabolites (oligosaccharides with a molecular weight lower than 1 kDa) in the individual reactors were quan...

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

    Directory of Open Access Journals (Sweden)

    MAHMOUD EL-HARIRI

    2015-12-01

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

  1. Antifungal activity of lemon, eucalyptus, thyme, oregano, sage and lavender essential oils against Aspergillus niger and Aspergillus tubingensis isolated from grapes

    Directory of Open Access Journals (Sweden)

    Miroslava Císarová

    2016-01-01

    Full Text Available Today, it is very important to find out the protection of products of natural origin as an alternative to synthetic fungicides. The promising alternative is the use of the essential oils (EOs. Essential oils from plants have great potential as a new source of fungicide to control the pathogenic fungi.The main objective of this study was evaluation of the antifungal activity of lemon (Citrus lemon L., eucalyptus (Eucalyptus globulus LABILL., thyme (Thymus vulgaris L., oregano (Origanum vulgare L. sage (Salvia officinalis L. and lavender (Lavandula angustifolia MILLER. EOs against Aspergillus niger and Aspergillus tubingensis isolated from grapes and their ability to affect the growth. It was tested by using the vapor contact with them. At first both tested isolates were identified by using PCR method. Sequence data of 18S rRNA supported the assignment of these isolates to the genus Aspergillus and species A. niger (ITS region: KT824061; RPB2: KT824060 and A. tubingensis (ITS region: KT824062; RPB2: KT824059. Second, EO antifungal activity was evaluated. The effect of the EO volatile phase was confirmed to inhibit growth of A. niger and A tubingensis. EOs were diluted in DMSO (dimethyl sulfoxide final volume of 100 μL. Only 50 μL this solution was distributed on a round sterile filter paper (1 x 1 cm by micropipette, and the paper was placed in the center of the lid of Petri dishes. Dishes were kept in an inverted position. The essential oils with the most significant activity were determined by method of graded concentration of oils - minimum inhibitory doses (MIDs. The most effective tested EOs were oregano and thyme oils, which totally inhibited growth of tested isolates for all days of incubation at 0.625 μL.cm-3 (in air with MFDs 0.125 μL.cm-3 (in air. Lavender EO was less active aginst tested strains (MIDs 0.313 μL.cm-3. The results showed that the tested EOs had antifungal activity, except lemon and eucalyptus. Sage EO was the only

  2. A biodegradation study of forest biomass by Aspergillus niger F7: correlation between enzymatic activity, hydrolytic percentage and biodegradation index

    Directory of Open Access Journals (Sweden)

    Nivedita Sharma

    2012-06-01

    Full Text Available Aspergillus niger F7 isolated from soil was found to be the potent producer of cellulase and xylanase. The residue of forest species Toona ciliata, Celtris australis, Cedrus deodara and Pinus roxburghii was selected as substrate for biodegradation study due to its easy availability and wide use in industry. It was subjected to alkali (sodium hydroxide treatment for enhancing its degradation. Biodegradation of forest waste by hydrolytic enzymes (cellulase and xylanase secreted by A. niger under solid state fermentation (SSF was explored. SSF of pretreated forest biomass was found to be superior over untreated forest biomass. Highest extracellular enzyme activity of 2201±23.91 U/g by A. niger was shown in pretreated C. australis wood resulting in 6.72±0.20 percent hydrolysis and 6.99±0.23 biodegradation index (BI. The lowest BI of 1.40±0.08 was observed in untreated saw dust of C. deodara having the least enzyme activity of 238±1.36 U/g of dry matter. Biodegradation of forest biomass under SSF was increased many folds when moistening agent i.e. tap water had been replaced with modified basal salt media (BSM. In BSM mediated degradation of forest waste with A. niger, extracellular enzyme activity was increased up to 4089±67.11 U/g of dry matter in turn resulting in higher BI of 15.4±0.41 and percent hydrolysis of 19.38±0.81 in pretreated C. australis wood. A. niger exhibited higher enzyme activity on pretreated biomass when moistened with modified BSM in this study. Statistically a positive correlation has been drawn between these three factors i.e. enzyme activity, BI and percent hydrolysis of forest biomass thus proving their direct relationship with each other.

  3. Increased resistance to 14 alpha-demethylase inhibitors (DMIs) in Aspergillus niger by coexpression of the Penicillium itulicum eburicol 14 alpha-demethylase (cyp51) and the A-niger cytochromeP450 reductase (cprA) genes

    NARCIS (Netherlands)

    Brink, van den J.M.; Nistelrooy, van J.G.M.; Waard, de M.A.; Hondel, van den C.A.M.J.J.; Gorcom, van R.F.M.

    1996-01-01

    In this paper we describe the effects of over-expression of the Penicillium italicum gene encoding eburicol 14α-demethylase (cyp51), in Aspergillus niger strains with one or multiple copies of the gene encoding cytochrome P450 reductase (cprA), on the eburicol 14α-demethylase activity. Eburicol 14α-

  4. Microbial conversion of ginsenoside Rd from Rb1 by the fungus mutant Aspergillus niger strain TH-10a.

    Science.gov (United States)

    Feng, Li; Xu, Chunchun; Li, Zhuo; Li, Jing; Dai, Yulin; Han, Hongxiang; Yu, Shanshan; Liu, Shuying

    2016-05-18

    Ginsenoside Rd, one of the ginsenosides with significant pharmaceutical activities, is getting more and more attractions on its biotransformation. In this study, a novel fungus mutant, the Aspergillus niger strain TH-10a, which can efficiently convert ginsenoside Rd from Rb1, was obtained through screening survival library of LiCl and ultraviolet (UV) irradiation. The transformation product ginsenoside Rd, generated by removing the outer glucose residue from the position C20 of ginsenoside Rb1, was identified through high-performance liquid chromatography (HPLC) analysis. Factors for the microbial culture and biotransformation were investigated in terms of the carbon sources, the nitrogen sources, pH values, and temperatures. This showed that maximum mycelia growth could be obtained at 28°C and pH 6.0 with cellobiose and tryptone as the carbon source and the nitrogen source, respectively. The highest transformation rate (∼86%) has been achieved at 32°C and pH 5.0 with the feeding time of substrate 48 hr. Also, Aspergillus niger strain TH-10a could tolerate even 40 mg/mL ginseng root extract as substrate with 60% bioconversion rate after 72 hr of treatment at the optimal condition. Our results highlight a novel ginsenoside Rd transformation fungus and illuminate its potentially practical application in the pharmaceutical industries. PMID:25831478

  5. Enhanced hexadecane degradation and low biomass production by Aspergillus niger exposed to an electric current in a model system.

    Science.gov (United States)

    Velasco-Alvarez, Nancy; González, Ignacio; Damian-Matsumura, Pablo; Gutiérrez-Rojas, Mariano

    2011-01-01

    The effects of an electric current on growth and hexadecane (HXD) degradation by Aspergillus niger growth were determined. A 450-mL electrochemical cell with titanium ruthenium-oxide coated electrodes and packed with 15 g of perlite (inert biomass support) was inoculated with A. niger (2.0×10(7) spores (g of dry inert support)(-1)) and incubated for 12 days (30 °C; constant ventilation). 4.5 days after starting culture a current of 0.42 mA cm(-2) was applied for 24h. The current reduced (52±11%) growth of the culture as compared to that of a culture not exposed to current. However, HXD degradation was 96±1.4% after 8 days whereas it was 81±1.2% after 12 days in control cultures. Carbon balances of cultures not exposed to current suggested an assimilative metabolism, but a non-assimilative metabolism when the current was applied. This change can be related to an increase in total ATP content. The study contributes to the knowledge on the effects of current on the mycelial growth phase of A. niger, and suggests the possibility of manipulating the metabolism of this organism with electric current. PMID:20739180

  6. Biotransformation of Isolan dyes by Aspergillus niger ES-5 under Co-metabolic Conditions for Glucose Oxidase Production

    International Nuclear Information System (INIS)

    Aspergillus niger ES-5 isolated from Egyptian soil was chosen for its high decolorizing performance (90-98.8%) of 4 Isolan dyes (metal reactive azo group). The decolorisation profile was highly dependent on the presence or absence of co-substrates needed for glucose oxidase (GOD) production. The extracellular fluid (ECF), autoclaved mycelia and mycelia grown in dye solution with no supplements showed a sharp drop in decolorisation (0-7.3%) confirming the biological involvement of growth-linked enzymatic system. The metal content of Isolan dyes was analyzed by Energy Dispersive Xray Spectroscopy (EDS), Cr, Cu, Zn and S were found in cultures, and were below the detection limit after 72 hr incubation. A range of 8-50% decrease in decolorisation was obtained when gamma radiation (up to 8 KGy) was used in combination with fungal pellets. A. niger ES-5 showed over 80% decolorisation for a mixture of the 4 dyes, while decolorisation of real textile effluent showed 75%. All previous data suggest a metabolically mediated dye decolorisation mechanism for live A. niger ES- 5 and points to its potential use in dye decolorisation of real textile effluent

  7. Effect of citrate on Aspergillus niger phytase adsorption and catalytic activity in soil

    Science.gov (United States)

    Mezeli, Malika; Menezes-Blackburn, Daniel; Zhang, Hao; Giles, Courtney; George, Timothy; Shand, Charlie; Lumsdon, David; Cooper, Patricia; Wendler, Renate; Brown, Lawrie; Stutter, Marc; Blackwell, Martin; Darch, Tegan; Wearing, Catherine; Haygarth, Philip

    2015-04-01

    Current developments in cropping systems that promote mobilisation of phytate in agricultural soils, by exploiting plant-root exudation of phytase and organic acids, offer potential for developments in sustainable phosphorus use. However, phytase adsorption to soil particles and phytate complexion has been shown to inhibit phytate dephosphorylation, thereby inhibiting plant P uptake, increasing the risk of this pool contributing to diffuse pollution and reducing the potential benefits of biotechnologies and management strategies aimed to utilise this abundant reserve of 'legacy' phosphorus. Citrate has been seen to increase phytase catalytic efficiency towards complexed forms of phytate, but the mechanisms by which citrate promotes phytase remains poorly understood. In this study, we evaluated phytase (from Aspergillus niger) inactivation, and change in catalytic properties upon addition to soil and the effect citrate had on adsorption of phytase and hydrolysis towards free, precipitated and adsorbed phytate. A Langmuir model was fitted to phytase adsorption isotherms showing a maximum adsorption of 0.23 nKat g-1 (19 mg protein g-1) and affinity constant of 435 nKat gˉ1 (8.5 mg protein g-1 ), demonstrating that phytase from A.niger showed a relatively low affinity for our test soil (Tayport). Phytases were partially inhibited upon adsorption and the specific activity was of 40.44 nKat mgˉ1 protein for the free enzyme and 25.35 nKat mgˉ1 protein when immobilised. The kinetics of adsorption detailed that most of the adsorption occurred within the first 20 min upon addition to soil. Citrate had no effect on the rate or total amount of phytase adsorption or loss of activity, within the studied citrate concentrations (0-4mM). Free phytases in soil solution and phytase immobilised on soil particles showed optimum activity (>80%) at pH 4.5-5.5. Immobilised phytase showed greater loss of activity at pH levels over 5.5 and lower activities at the secondary peak at pH 2

  8. Can hTNF-alpha be successfully produced and secreted in filamentous fungus Aspergillus niger?

    NARCIS (Netherlands)

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

    2000-01-01

    A gene-fusion expression strategy was applied for the heterologous expression of hTNF-α in A. niger AB1.13. The TNF-α gene was fused with the A. niger glucoamylase GII form as a carrier-gene, behind its transcription control and secretion signal. The protein was expressed in the cells in the form of

  9. Review of secondary metabolites and mycotoxins from the Aspergillus niger group

    DEFF Research Database (Denmark)

    Nielsen, Kristian Fog; Mogensen, Jesper Mølgaard; Johansen, Maria;

    2009-01-01

    (excluding A. aculeatus and its close relatives) from which currently 145 different secondary metabolites have been isolated and/or detected. From a human and animal safety point of view, the mycotoxins ochratoxin A (from A. carbonarius and less frequently A. niger) and fumonisin B2 (from A. niger) are...

  10. Aborto por Aspergillus fumigatus e A. niger em bovinos no sul do Brasil

    Directory of Open Access Journals (Sweden)

    Corbellini Luís G.

    2003-01-01

    Full Text Available As infecções micóticas apresentam distribuição mundial e podem causar placentite e aborto em diversas espécies de animais. Entre setembro 2001 e novembro 2002, foram processados no Setor de Patologia Veterinária, Universidade Federal do Rio Grande do Sul, 147 fetos bovinos abortados com o objetivo de avaliar as principais causas de aborto infeccioso bovino no sul do Brasil. Destes, 34 estavam acompanhados da placenta. Aborto micótico foi diagnosticado em cinco casos (3,4% mediante cultivo puro de quatro amostras de Aspergillus fumigatus e uma de A. niger associado a lesões histológicas características de fungo. Os exames virológico, bacteriológico e imunofluorescência direta para Leptospira sp foram negativos nestes casos. A idade dos fetos variava entre 5 e 8 meses de idade. Lesões macroscópicas foram observadas em quatro casos e eram caracterizadas por áreas circulares multifocais branco-acinzentadas na pele, principalmente na região da cabeça e dorso, em dois fetos, lesões nodulares no fígado em um caso e espessamento dos cotilédones em duas placentas enviadas juntamente com os fetos. Lesões histológicas foram observadas principalmente no fígado, pulmão e placenta, caracterizadas por hepatite necrótica multifocal, broncopneumonia supurativa e placentite necrótica. Através da coloração de Grocott hifas septadas foram observadas em duas placentas e nas bordas das lesões necróticas no fígado de um feto. Em dois casos hifas foram observadas somente na placenta e não no feto, salientando-se a importância deste tecido para o diagnóstico de aborto micótico bovino.

  11. Submerged culture for production of ellagic acid from pomegranate husk by Aspergillus niger GH1

    Directory of Open Access Journals (Sweden)

    L. Sepúlveda

    2014-01-01

    Full Text Available El ácido elágico es un compuesto bioactivo derivado de la hidrólisis de los elagitaninos. El ácido elágico tiene importantes aplicaciones en la industria de alimentos, farmacéutica y cosmética, debido a que presenta propiedades biológicas benéficas. El ácido elágico se obtiene de diferentes fuentes, tales como bayas de frutas, plantas del semi-desierto, y corteza de encinos. La cáscara de granada contiene una gran proporción de elagitaninos, los cuales pueden ser biotransformados en ácido elágico mediante bioprocesos fúngicos, aunque no existe producción biotecnológica industrial. El objetivo de este trabajo fue encontrar las condiciones apropiadas para la producción de ácido elágico por Aspergillus niger GH1 en cultivo sumergido, a partir del polvo de cáscara de granada. Se utilizó un diseño Box-Bhenken para estudiar la influencia de los factores de cultivo sobre la producción de ácido elágico. La mayor producción de ácido elágico fue de 21.19 mg g -1 de cáscara de granada en polvo. El sustrato y el pH influyeron directamente sobre la producción de ácido elágico. Se observó un consumo constante durante la cinética de taninos hidrolizables (elagitaninos presentes en el sustrato. La máxima acumulación de proteínas se alcanzó a las 24 h, lo cual se puede asociar con la actividad de algunas enzimas presentes en el cultivo. Las mejores condiciones de producción de ácido elágico en cultivo sumergido fueron: una concentración de sustrato de 7.5 g L -1 , pH 5.5, y una agitación de 150 rpm. El sistema desarrollado representa una alternativa para la producción de ácido elágico a gran escala.

  12. The transcriptional activator GaaR of Aspergillus niger is required for release and utilization of D-galacturonic acid from pectin

    NARCIS (Netherlands)

    Alazi, Ebru; Niu, Jing; Kowalczyk, Joanna E; Peng, Mao; Aguilar Pontes, Maria Victoria; van Kan, Jan A L; Visser, Jaap; de Vries, Ronald P; Ram, Arthur F J

    2016-01-01

    We identified the D-galacturonic acid (GA) responsive transcriptional activator GaaR of the saprotrophic fungus Aspergillus niger, which was found to be essential for growth on GA and polygalacturonic acid (PGA). Growth of the ΔgaaR strain was reduced on complex pectins. Genome-wide expression analy

  13. The transcriptional activator GaaR of Aspergillus niger is required for release and utilization of d-galacturonic acid from pectin

    NARCIS (Netherlands)

    Alazi, Ebru; Niu, Jing; Kowalczyk, Joanna E.; Peng, Mao; Aguilar Pontes, Maria Victoria; Kan, Van Jan A.L.; Visser, Jaap; Vries, De Ronald P.; Ram, Arthur F.J.

    2016-01-01

    We identified the d-galacturonic acid (GA)-responsive transcriptional activator GaaR of the saprotrophic fungus, Aspergillus niger, which was found to be essential for growth on GA and polygalacturonic acid (PGA). Growth of the ΔgaaR strain was reduced on complex pectins. Genome-wide expression anal

  14. Phosphate solubilization and promotion of maize growth in a calcareous soil by Penicillium oxalicum P4 and Aspergillus niger P85

    Science.gov (United States)

    Alternative tactics for improving phosphorus nutrition in crop production are needed in China and elsewhere as the over-application of phosphatic fertilizers can adversely impact agricultural sustainability. Penicillium oxalicum P4 and Aspergillus niger P85 were isolated from a calcareous soil in C...

  15. Impact of Assay conditions on activity estimate and kinetics comparison of Aspergillus niger PhyA and Escherichia coli AppA2 phytases

    Science.gov (United States)

    This study was to compare three phytase activity assays and kinetics of Aspergillus niger PhyA and Escherichia coli AppA2 phytases expressed in Pichia pastoris at the observed stomach pH of 3.5. In Experiment 1, equivalent phytase activities in the crude preparations of PhyA and AppA2 were tested ...

  16. Aspergillus niger mstA encodes a high affinity sugar/H+ symporter which is regulated in persponse to extracellular pH

    NARCIS (Netherlands)

    Kuyk, van P.A.; Diderich, J.A.; MacCabe, A.P.; Hererro, O.; Ruijter, G.J.G.; Visser, J.

    2004-01-01

    A sugar-transporter-encoding gene, mstA, which is a member of the major facilitator superfamily, has been cloned from a genomic DNA library of the filamentous fungus Aspergillus niger. To enable the functional characterization of MSTA, a full-length cDNA was expressed in a Saccharomyces cerevisiae s

  17. Correlation of Mycotoxin Fumonisin B2 Production and Presence of the Fumonisin Biosynthetic Gene fum8 in Aspergillus niger from Grape

    Science.gov (United States)

    Fumonisins are mycotoxins associated with cancer and several other serious diseases in humans and animals. Production of the mycotoxins has been reported for over two decades in Fusarium species, but has been reported only recently in strains of Aspergillus niger. In addition, a homologue of the f...

  18. Aspergillus niger genome-wide analysis reveals a large number of novel alpha-glucan acting enzymes with unexpected expression profiles

    NARCIS (Netherlands)

    Yuan, X.-L.; Kaaij, R.M. van der; Hondel, C.A.M.J.J. van den; Punt, P.J.; Maarel, M.J.E.C. van der; Dijkhuizen, L.; Ram, A.F.J.

    2008-01-01

    The filamentous ascomycete Aspergillus niger is well known for its ability to produce a large variety of enzymes for the degradation of plant polysaccharide material. A major carbon and energy source for this soil fungus is starch, which can be degraded by the concerted action of α-amylase, glucoamy

  19. The role of the Aspergillus niger furin-type protease gene in processing of fungal proproteins and fusion proteins: Evidence for alternative processing of recombinant (fusion-) proteins

    NARCIS (Netherlands)

    Punt, P.J.; Drint-Kuijvenhoven, A.; Lokman, B.C.; Spencer, J.A.; Jeenes, D.; Archer, D.A.; Hondel, C.A.M.J.J. van den

    2003-01-01

    We have characterized growth and protein processing characteristics of Aspergillus niger strains carrying a disrupted allele of the previously cloned and characterized kexB gene [Appl. Environ. Microbiol. 66 (2000) 363] encoding a furin-type endoprotease. Deletion of the single-copy gene confirms it

  20. Characterization of a polyketide synthase in Aspergillus niger whose product is a precursor for both dihydroxynaphthalene (DHN) melanin and naphtho-γ-pyrone.

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Yi Ming; Meyer, Kristen M; Praseuth, Michael; Baker, Scott E; Bruno, Kenneth S; Wang, Clay C

    2010-12-06

    The genome sequencing of the fungus Aspergillus niger, an industrial workhorse, uncovered a large cache of genes encoding enzymes thought to be involved in the production of secondary metabolites yet to be identified. Identification and structural characterization of many of these predicted secondary metabolites are hampered by their low concentration relative to the known A. niger metabolites such as the naphtho-γ-pyrone family of polyketides. We deleted a nonreducing PKS gene in A. niger strain ATCC 11414, a daughter strain of A. niger ATCC strain 1015 whose genome was sequenced by the DOE Joint Genome Institute. This PKS encoding gene is a predicted ortholog of alb1 from Aspergillus fumigatus which is responsible for production of YWA1, a precursor of fungal DHN melanin. Our results show that the A. niger alb1 PKS is responsible for the production of the polyketide precursor for DHN melanin biosynthesis. Deletion of alb1 elimnates the production of major metabolites, naphtho-γ-pyrones. The generation of an A. niger strain devoid of naphtho-γ-pyrones will greatly facilitate the elucidation of cryptic biosynthetic pathways in this organism.

  1. Response surface optimization for enhanced production of cellulases with improved functional characteristics by newly isolated Aspergillus niger HN-2.

    Science.gov (United States)

    Oberoi, Harinder Singh; Rawat, Rekha; Chadha, Bhupinder Singh

    2014-01-01

    Fungi isolated from partially decayed wood log samples showing characteristic diversity for spore colour, colony morphology and arrangement of spores were assessed for cellulolytic enzyme production. Isolates showing a cellulolytic index of ≥2.0 were assayed for filter paper (FP) cellulase and β-glucosidase (BGL) production. Molecular characterization confirmed the identity of the selected cellulolytic isolate as a strain of Aspergillus niger (A. niger HN-2). Addition of 2 % (w/v) urea enhanced FP and BGL activity by about 20 and 60 %, respectively. Validation studies conducted at parameters (29 °C, pH 5.4, moisture content 72 % and 66 h) optimized through response surface methodology in a solid-state static tray fermentation resulted in FP, BGL, cellobiohydrolase I (CBHI), endoglucanase (EG), xylanase activity and protein content of 25.3 FPU/g ds, 750 IU/g ds, 13.2 IU/g ds, 190 IU/g ds, 2890 IU/g ds and 0.9 mg/ml, respectively. In comparison, A. niger N402 which is a model organism for growth and development studies, produced significantly lower FP, BGL, CBHI, EG, xylanase activity and protein content of 10.0 FPU/g ds, 100 IU/g ds, 2.3 IU/g ds, 50 IU/g ds, 500 IU/g ds and 0.75 mg/ml, respectively under the same process conditions as were used for A. niger HN-2. Process optimization led to nearly 1.8- and 2.2-fold increase in FP and BGL activity, respectively showing promise for cellulase production by A. niger HN-2 at a higher scale of operation. Zymogram analysis revealed two isoforms each for EG and cellobiohydrolase and three isoforms for BGL. Crude cellulase complex produced by A. niger HN-2 exhibited thermostability under acidic conditions showing potential for use in biofuel industry. PMID:24158534

  2. The intra- and extracellular proteome of Aspergillus niger growing on defined medium with xylose or maltose as carbon substrate

    Directory of Open Access Journals (Sweden)

    Wissing Josef

    2010-04-01

    Full Text Available Abstract Background The filamentous fungus Aspergillus niger is well-known as a producer of primary metabolites and extracellular proteins. For example, glucoamylase is the most efficiently secreted protein of Aspergillus niger, thus the homologous glucoamylase (glaA promoter as well as the glaA signal sequence are widely used for heterologous protein production. Xylose is known to strongly repress glaA expression while maltose is a potent inducer of glaA promoter controlled genes. For a more profound understanding of A. niger physiology, a comprehensive analysis of the intra- and extracellular proteome of Aspergillus niger AB1.13 growing on defined medium with xylose or maltose as carbon substrate was carried out using 2-D gel electrophoresis/Maldi-ToF and nano-HPLC MS/MS. Results The intracellular proteome of A. niger growing either on xylose or maltose in well-aerated controlled bioreactor cultures revealed striking similarities. In both cultures the most abundant intracellular protein was the TCA cycle enzyme malate-dehydrogenase. Moreover, the glycolytic enzymes fructose-bis-phosphate aldolase and glyceraldehyde-3-phosphate-dehydrogenase and the flavohemoglobin FhbA were identified as major proteins in both cultures. On the other hand, enzymes involved in the removal of reactive oxygen species, such as superoxide dismutase and peroxiredoxin, were present at elevated levels in the culture growing on maltose but only in minor amounts in the xylose culture. The composition of the extracellular proteome differed considerably depending on the carbon substrate. In the secretome of the xylose-grown culture, a variety of plant cell wall degrading enzymes were identified, mostly under the control of the xylanolytic transcriptional activator XlnR, with xylanase B and ferulic acid esterase as the most abundant ones. The secretome of the maltose-grown culture did not contain xylanolytic enzymes, instead high levels of catalases were found and

  3. Comparative study of toxicity of azo dye Procion Red MX-5B following biosorption and biodegradation treatments with the fungi Aspergillus niger and Aspergillus terreus.

    Science.gov (United States)

    Almeida, E J R; Corso, C R

    2014-10-01

    Azo dyes are an important class of environmental contaminants and are characterized by the presence of one or more azo bonds (-N=N-) in their molecular structure. Effluents containing these compounds resist many types of treatments due to their molecular complexity. Therefore, alternative treatments, such as biosorption and biodegradation, have been widely studied to solve the problems caused by these substances, such as their harmful effects on the environment and organisms. The aim of the present study was to evaluate biosorption and biodegradation of the azo dye Procion Red MX-5B in solutions with the filamentous fungi Aspergillus niger and Aspergillus terreus. Decolorization tests were performed, followed by acute toxicity tests using Lactuca sativa seeds and Artemia salina larvae. Thirty percent dye removal of the solutions was achieved after 3 h of biosorption. UV-Vis spectroscopy revealed that removal of the dye molecules occurred without major molecular changes. The acute toxicity tests confirmed lack of molecular degradation following biosorption with A. niger, as toxicity to L. sativa seed reduced from 5% to 0%. For A. salina larvae, the solutions were nontoxic before and after treatment. In the biodegradation study with the fungus A. terreus, UV-Vis and FTIR spectroscopy revealed molecular degradation and the formation of secondary metabolites, such as primary and secondary amines. The biodegradation of the dye molecules was evaluated after 24, 240 and 336 h of treatment. The fungal biomass demonstrated considerable affinity for Procion Red MX-5B, achieving approximately 100% decolorization of the solutions by the end of treatment. However, the solutions resulting from this treatment exhibited a significant increase in toxicity, inhibiting the growth of L. sativa seeds by 43% and leading to a 100% mortality rate among the A. salina larvae. Based on the present findings, biodegradation was effective in the decolorization of the samples, but generated

  4. Efficiency of the fungus Aspergillus niger biomass in Pentachlorophenol (PCP absorption from aqueous solutions

    Directory of Open Access Journals (Sweden)

    Reza Shokoohi

    2014-10-01

    Conclusion: The results show that absorption efficiency increases by rising retention time under constant conditions. In addition, at low pH the modified A. niger biomass could be a good absorber for PCP.

  5. Produção de celulases por Aspergillus niger e cinética da desativação celulásica=Cellulases production by Aspergillus niger and cellulase deactivation kinetic

    Directory of Open Access Journals (Sweden)

    Caroline Mariana de Aguiar

    2011-10-01

    Full Text Available O presente trabalho teve como objetivo a avaliação da cinética de produção de enzimas celulases pelo fungo Aspergillus niger e da cinética de desativação das celulases. Foi utilizado bagaço de cana-de-açúcar pré-tratado como fonte de carbono na fermentação para a produção do complexo celulásico e também como substrato da hidrólise enzimática. A. niger foi cultivado em três bateladas, cada uma contendo 10, 50 e 100 g L-1 de bagaço pré-tratado com NaOH 4% (m v-1. A cinética da produção das celulases foi obtida determinando-se a atividade enzimática das amostras coletadas ao longo do tempo. As variações do pH também foram determinadas. A deativação enzimática foi avaliada determinando-se periodicamente a atividade das amostras armazenadas nas condições de resfriamento (4°C e de congelamento (-18ºC. Conclui-se que o A. niger produz celulases quando cultivado em meio de cultivo contendo bagaço de cana-de-açúcar pré-tratado e que o tempo ideal para coleta do caldo enzimático foi de aproximadamente sete dias, com produtividade máxima de 0,0013 U mL-1∙h para a batelada com 10 g L-1 e 0,0018 U mL-1∙h para as bateladas com 50 e 100 g L-1. O complexo celulásico não sofre desativação se armazenado à temperatura de -18°C por 43 dias, mas perde cerca de 40% da sua atividade após 48h se armazenado a 4°C.This work aimed to evaluate the kinetic for the cellulase production by Aspergillus niger and the deactivation kinetic of the cellulase enzymes. Cellulase were produced in three different batches using NaOH 4% (w v-1 pre-treated sugarcane bagasse as the carbon source in the fermentation broth. The amount of the bagasse in each batch was 10, 50 and 100 g L-1. The kinetic of the cellulase production was accomplished by periodically determining the cellulasic activity of the fermentation broth using pre-treated bagasse as the hydrolysis substrate. Changes in the pH also were determined. The cellulase

  6. Influência da glicose sobre o consumo de fenol por Aspergillus niger an 400 em reatores em batelada The influence of glucose on the phenol consumption by Aspergillus niger an 400 in batch reactors

    OpenAIRE

    Kelly de Araújo Rodrigues; Glória Maria Marinho S. Sampaio; Marcelo Zaiat; Sandra Tédde Santaella

    2007-01-01

    Aspergillus niger AN 400 foi inoculado em reatores em batelada para remoção de fenol de meio sintético, na presença e ausência de glicose. O experimento possuía: 5 reatores de controle (grupo 1) com meio contento apenas fenol; 5 reatores (grupo 2) inoculados com fungos e com meio com fenol e sem glicose; e 5 reatores (grupo 3) inoculados com fungos e com meio com fenol e glicose (5 g/L). Os reatores foram agitados a 200 rpm, a 30°C, durante 5 dias. A concentração média inicial de fenol foi de...

  7. [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

  8. Sugarcane molasses and yeast powder used in the Fructooligosaccharides production by Aspergillus japonicus-FCL 119T and Aspergillus niger ATCC 20611.

    Science.gov (United States)

    Dorta, Claudia; Cruz, Rubens; de Oliva-Neto, Pedro; Moura, Danilo José Camargo

    2006-12-01

    Different concentrations of sucrose (3-25% w/v) and peptone (2-5% w/v) were studied in the formulation of media during the cultivation of Aspergillus japonicus-FCL 119T and Aspergillus niger ATCC 20611. Moreover, cane molasses (3.5-17.5% w/v total sugar) and yeast powder (1.5-5% w/v) were used as alternative nutrients for both strains' cultivation. These media were formulated for analysis of cellular growth, beta-Fructosyltransferase and Fructooligosaccharides (FOS) production. Transfructosylating activity (U ( t )) and FOS production were analyzed by HPLC. The highest enzyme production by both the strains was 3% (w/v) sucrose and 3% (w/v) peptone, or 3.5% (w/v) total sugars present in cane molasses and 1.5% (w/v) yeast powder. Cane molasses and yeast powder were as good as sucrose and peptone in the enzyme and FOS (around 60% w/w) production by studied strains. PMID:16835781

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

    Directory of Open Access Journals (Sweden)

    Shazia Rehman

    2014-12-01

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

  10. Caracterización de la biomasa inactiva de Aspergillus niger O-5 como sorbente de Pb (II

    Directory of Open Access Journals (Sweden)

    Yusleydi Enamorado Horrutiner

    2011-01-01

    Full Text Available The inactive biomass of fungus Aspergillus niger O-5 obtained in Cuba was characterized as sorbent of Pb2+ by several structural analysis and others techniques. In addition, the biomass was studied for the separation / preconcentration of Pb2+ from aqueous solution. The maximum biosorption capacity was obtained for the contact time of 30 min and pH 5. The kinetic of sorption process occurred according to the model of Ho. The Freundlich or Langmuir models suitably described the experimental adsorption isotherms. The biomass can be used as sorbent for Pb2+ with a maximum capacity of 4.7 - 6.2 mg g-1. The pretreatment with NaOH solution improved its sorption capacity.

  11. High titer gluconic acid fermentation by Aspergillus niger from dry dilute acid pretreated corn stover without detoxification.

    Science.gov (United States)

    Zhang, Hongsen; Zhang, Jian; Bao, Jie

    2016-03-01

    This study reported a high titer gluconic acid fermentation using dry dilute acid pretreated corn stover (DDAP) hydrolysate without detoxification. The selected fermenting strain Aspergillus niger SIIM M276 was capable of inhibitor degradation thus no detoxification on pretreated corn stover was required. Parameters of gluconic acid fermentation in corn stover hydrolysate were optimized in flasks and in fermentors to achieve 76.67 g/L gluconic acid with overall yield of 94.91%. The sodium gluconate obtained from corn stover was used as additive for extending setting time of cement mortar and similar function was obtained with starch based sodium gluconate. This study provided the first high titer gluconic acid production from lignocellulosic feedstock with potential of industrial applications. PMID:26724553

  12. Kinetics of alcoholic fermentation using guava (psidium guajava) seed flour and dry mycelium of aspergillus niger as nitrogen sources

    OpenAIRE

    LILIANA SERNA COCK; JOSÉ DANIEL MERA AYALA; JORGE EDUARDO ANGULO LÓPEZ; ANA LUCIA GÓMEZ SCHOUBEN

    2013-01-01

    Para la cinética de fermentación alcohólica se evaluaron como sustratos melaza más urea y fosfato diamónico (MUFD), melaza más harina de semilla de guayaba (MHSG) y melaza más micelio seco de Aspergillus niger (MMAN). Las fermentaciones se realizaron anaeróbicamente, a 32°C, pH 4.6 y usando Saccharomyces cerevisiae. Para los sustratos mencionados se estudió el efecto de la fuente de nitrógeno en la viabilidad celular (V), conversión de sustrato (CS), rendimiento en etanol (Y) y productividad....

  13. INFLUENCE OF SOLID MOISTURE AND BED HEIGHT ON CULTIVATION OF Aspergillus niger FROM SUGARCANE BAGASSE WITH VINASSE

    Directory of Open Access Journals (Sweden)

    R. G. Bastos

    2015-06-01

    Full Text Available AbstractSolid-state cultivation (SSC may be defined as growth of microorganisms on a solid support impregnated or not with a nutrient solution in near absence of free-water conditions. The use of sugarcane bagasse as a support for SSC usually demands that the particles are impregnated and moistened with nutrient solution. Vinasse is the main wastewater of ethanol fermentation-distillation. As there are no reports of the use of wastewater for moistening solid supports in SSC, the proposal is the development of an innovative process, with valuation of these by-products. Thus, the aim of this research was to evaluate SSC of Aspergillus niger using sugarcane bagasse and vinasse for citric acid production. The results indicate that citric acid production and glucose consumption are dependent on oxygen availability, which can be modulated by selection of bed height and air-flow in packed-bed bioreactors.

  14. Effects of Aspergillus niger fermented rapeseed meal on nutrient digestibility, growth performance and serum parameters in growing pigs.

    Science.gov (United States)

    Shi, Changyou; He, Jun; Wang, Jianping; Yu, Jie; Yu, Bing; Mao, Xiangbing; Zheng, Ping; Huang, Zhiqing; Chen, Daiwen

    2016-04-01

    The aim of the present study was to investigate the influences of Aspergillus niger fermented rapeseed meal (FRSM) on growth performance and nutrient digestibility of growing pigs. A total of 72 growing pigs (body weight = 40.8 ± 2.1 kg) were used in feeding trials, lasting for up to 42 days, and were randomly allotted to one of three diets, including a corn-soybean meal control diet as well as two experimental diets containing 10% unfermented rapeseed meal (RSM) or 10% FRSM. The results showed that average daily gain and feed conversion ratio of pigs fed FRSM were superior (P growth performance and nutrient digestibility of RSM for pigs and FRSM is a promising alternative protein for pig production. PMID:26434567

  15. Studies on production of single cell protein by Aspergillus niger in solid state fermentation of rice bran

    Directory of Open Access Journals (Sweden)

    Anupama

    2001-01-01

    Full Text Available An attempt was made to apply the solid state fermentation (SSF for the production of single cell protein (SCP using oil free rice bran waste as substrate. A local isolate of Aspergillus niger, was used as protein source for the studies. Total proteins were extracted to estimate the mycelial biomass from the moldy bran. Carbonate-bicarbonate extraction buffer and a pH 10 was found to be most efficient among the buffers used for the extraction of the proteins from the organism. The effect of supplementation by various sources of nitrogen and mineral solution on the final biomass yield was compared. The influence of C/N ratio on the protein yield was also studied. Sodium nitrate at C/N ratio of 1.387 was found to be an effective nitrogen-supplementing source, as it gave the higher biomass yield.

  16. Biochemical characterization of N-methyl N' -nitro-N-nitrosoguanidine-induced cadmium resistant mutants of Aspergillus niger

    Indian Academy of Sciences (India)

    Samar Kumar Pal; Tapan Kumar Das

    2005-12-01

    Two cadmium resistant mutants (Cd1 and Cd2) of Aspergillus niger, among the six isolated by mutagenization with N-methyl N′-nitro-N-nitrosoguanidine (MNNG) at pH 6.4 were selected for the study. Analysis of lipid composition of the mutants and the wildtype indicated that total lipid as well as individual lipids of the cadmium resistant mutants were changed as compared with that of the wildtype. The increased activities of metal-lothionein and reduced activities of D-xylose isomerase and L-phenylalanine ammonia lyase in cell free extract of the cadmium resistant mutants suggested that mutants could allow high concentration of cadmium salt as compared with that of the wildtype. The respiratory activity and intracellular as well as extracellular Cd2+ concentration of the mutants reflected the high tolerance of the Cd mutants to cadmium ion.

  17. A NOVEL STRAIN OF Aspergillus niger PRODUCING A COCKTAIL OF HYDROLYTIC DEPOLYMERISING ENZYMES FOR THE PRODUCTION OF SECOND GENERATION BIOFUELS

    Directory of Open Access Journals (Sweden)

    Namita Bansal

    2011-02-01

    Full Text Available The screening and isolation of fungi producing a cocktail of hydrolytic enzymes was studied. Among the various isolates obtained from different soil samples, a strain NS-2 was selected. The phylogenetic analysis of this strain showed highest homology (99% with Aspergillus niger. It was capable of producing cellulolytic, hemicellulolytic, amylolytic, and pectinolytic enzymes in appreciable titers on wheat bran based liquid and solid state media. The mixture of enzymes produced by this organism could effectively hydrolyze various domestic waste residues, revealing conversion efficiencies of 89 to 92% and produced high reducing sugar yields of 0.48 to 0.66 g/g of dry residue. This enzyme cocktail could potentially find a significant application in the conversion of agricultural and other waste residues having cellulose, hemicellulose, starch, and pectin as carbohydrates to produce simpler sugars which can be fermented for the production of second generation biofuels.

  18. Bio sorption of Reactive Dye from Textile Wastewater by Non-viable Biomass of Aspergillus niger and Spirogyra sp

    International Nuclear Information System (INIS)

    The Potential of Aspergillus niger fungus and Spirogyra sp., a fresh water green algae, was investigated as a bio sorbents for removal of reactive dye (Synazol) from its multi-component textile wastewater. Pre-treatment of fungal and algal biomass with autoclaving increased the removal of dye more than that pre-treated with gamma-irradiation. The heat dried autoclaved biomass for the 2 organisms exhibited maximum dye removal at ph 3, temperature 30 degree C and 8 g/l (w/v) biomass conc. after 18 h contact time. The results showed that the non-viable biomass possessed high stability and efficiency of dye removal over 3 repeated batches

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

    Energy Technology Data Exchange (ETDEWEB)

    Grigoriev, Igor V.; Baker, Scott E.; Andersen, Mikael R.; Salazar, Margarita P.; Schaap, Peter J.; Vondervoot, Peter J.I. van de; Culley, David; Thykaer, Jette; Frisvad, Jens C.; Nielsen, Kristen F.; Albang, Richard; Albermann, Kaj; Berka, Randy M.; Braus, Gerhard H.; Braus-Stromeyer, Susanna A.; Corrochano, Luis M.; Dai, Ziyu; Dijck, Piet W.M. van; Hofmann, Gerald; Lasure, Linda L.; Magnusson, Jon K.; Meijer, Susan L.; Nielsen, Jakob B.; Nielsen, Michael L.; Ooyen, Albert J.J. van; Panther, Kathyrn S.; Pel, Herman J.; Poulsen, Lars; Samson, Rob A.; Stam, Hen; Tsang, Adrian; Brink, Johannes M. van den; Atkins, Alex; Aerts, Andrea; Shapiro, Harris; Pangilinan, Jasmyn; Salamov, Asaf; Lou, Yigong; Lindquist, Erika; Lucas, Susan; Grimwood, Jane; Kubicek, Christian P.; Martinez, Diego; Peij, Noel N.M.E. van; Roubos, Johannes A.; Nielsen, Jens

    2011-04-28

    The filamentous fungus Aspergillus niger exhibits great diversity in its phenotype. It is found globally, both as marine and terrestrial strains, produces both organic acids and hydrolytic enzymes in high amounts, and some isolates exhibit pathogenicity. Although the genome of an industrial enzyme-producing A. niger strain (CBS 513.88) has already been sequenced, the versatility and diversity of this species compels additional exploration. We therefore undertook whole genome sequencing of the acidogenic A. niger wild type strain (ATCC 1015), and produced a genome sequence of very high quality. Only 15 gaps are present in the sequence and half the telomeric regions have been elucidated. Moreover, sequence information from ATCC 1015 was utilized to improve the genome sequence of CBS 513.88. Chromosome-level comparisons uncovered several genome rearrangements, deletions, a clear case of strain-specific horizontal gene transfer, and identification of 0.8 megabase of novel sequence. Single nucleotide polymorphisms per kilobase (SNPs/kb) between the two strains were found to be exceptionally high (average: 7.8, maximum: 160 SNPs/kb). High variation within the species was confirmed with exo-metabolite profiling and phylogenetics. Detailed lists of alleles were generated, and genotypic differences were observed to accumulate in metabolic pathways essential to acid production and protein synthesis. A transcriptome analysis revealed up-regulation of the electron transport chain, specifically the alternative oxidative pathway in ATCC 1015, while CBS 513.88 showed significant up-regulation of genes relevant to glucoamylase A production, such as tRNA-synthases and protein transporters. Our results and datasets from this integrative systems biology analysis resulted in a snapshot of fungal evolution and will support further optimization of cell factories based on filamentous fungi.[Supplemental materials (10 figures, three text documents and 16 tables) have been made available

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

    Science.gov (United States)

    Prathumpai, Wai; Flitter, Simon J; McIntyre, Mhairi; Nielsen, Jens

    2004-11-01

    Two recombinant strains of Aspergillus niger (NW 297-14 and NW297-24) producing a heterologous lipase from Thermomyces lanuginosus were constructed. The heterologous lipase was expressed using the TAKA amylase promoter from Aspergillus oryzae. The production kinetics of the two strains on different carbon sources in batch and carbon-limited chemostat cultivations were evaluated. In batch cultivations, the highest total product yield coefficient (Y(xp total)), given as the sum of extracellular and intracellular yields, was obtained during growth on glucose for the transformant strain NW297-24 (5.7+/-0.65 KU/g DW), whereas the highest total product yield coefficient was obtained during growth on maltose for the transformant strain NW297-14 (6.3+/-0.02 KU/g DW). Both transformants were evaluated in glucose-limited chemostat cultures. Strain NW297-14 was found to be the best producer and was thus employed for further analysis of the influence of carbon source in chemostat cultures. Here, the highest total specific lipase productivity (r(p total), the sum of extracellular and intracellular lipase productivity) was found to be 1.60+/-0.81 KU/g DW/h in maltose-limited chemostats at a dilution rate of 0.08 h(-1), compared with a total specific lipase productivity of 1.10+/-0.41 KU/g DW/h in glucose-limited chemostats. At the highest specific productivity obtained in this study, the heterologous enzyme accounted for about 1% of all cellular protein being produced by the cells, which shows that it is possible to obtain high productivities of heterologous fungal enzymes in A. niger. However, SDS-PAGE analysis showed that most of the produced lipase was bound to the cell wall. PMID:15316684

  1. Isolation, molecular cloning and expression of cellobiohydrolase B (CbhB) from Aspergillus niger in Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Woon, J. S. K., E-mail: jameswoon@siswa.ukm.edu.my; Murad, A. M. A., E-mail: munir@ukm.edu.my; Abu Bakar, F. D., E-mail: fabyff@ukm.edu.my [School of Biosciences and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia)

    2015-09-25

    A cellobiohydrolase B (CbhB) from Aspergillus niger ATCC 10574 was cloned and expressed in E. coli. CbhB has an open reading frame of 1611 bp encoding a putative polypeptide of 536 amino acids. Analysis of the encoded polypeptide predicted a molecular mass of 56.2 kDa, a cellulose binding module (CBM) and a catalytic module. In order to obtain the mRNA of cbhB, total RNA was extracted from A. niger cells induced by 1% Avicel. First strand cDNA was synthesized from total RNA via reverse transcription. The full length cDNA of cbhB was amplified by PCR and cloned into the cloning vector, pGEM-T Easy. A comparison between genomic DNA and cDNA sequences of cbhB revealed that the gene is intronless. Upon the removal of the signal peptide, the cDNA of cbhB was cloned into the expression vector pET-32b. However, the recombinant CbhB was expressed in Escherichia coli Origami DE3 as an insoluble protein. A homology model of CbhB predicted the presence of nine disulfide bonds in the protein structure which may have contributed to the improper folding of the protein and thus, resulting in inclusion bodies in E. coli.

  2. The correlation between mannanase and cellulase activities towards fibre content of palm oil sludge fermented with Aspergillus niger

    Directory of Open Access Journals (Sweden)

    T. Purwadaria

    1998-12-01

    Full Text Available Enzyme (mannanase and cellulase activities and fibre (hemicellulose, cellulose and lignin contents were determined during the fermentation course of palm oil sludge with Aspergillus niger TL (wild type and A. niger ES I (an asporogenous mutant. The analyses were carried out at the incubation time of 3 and 4 days of aerobic fennentation and at 2 days of anaerobic fermentation afterward. The correlations between mamlanase activity with hemicellulose content and cellulose activity with cellulose content were calculated by linear regression . The activities of matutanase and cellulase are increasing during the aerobic fennentation, while in the anaerobic fennentation the enzyme activities are decreasing due to instability of the enzymes. The enzyme activities of ESI are higher than the TL. The regression coefficient is highly significant for correlation between mamlanase and hemicellulose content of fermented product by ESI (r = 0.83; P0 .05 . Marutanase and cellulase activities were also detected after the fermented product dried at 60°C which indicated the enzymes are quite stable .

  3. Isolation, molecular cloning and expression of cellobiohydrolase B (CbhB) from Aspergillus niger in Escherichia coli

    International Nuclear Information System (INIS)

    A cellobiohydrolase B (CbhB) from Aspergillus niger ATCC 10574 was cloned and expressed in E. coli. CbhB has an open reading frame of 1611 bp encoding a putative polypeptide of 536 amino acids. Analysis of the encoded polypeptide predicted a molecular mass of 56.2 kDa, a cellulose binding module (CBM) and a catalytic module. In order to obtain the mRNA of cbhB, total RNA was extracted from A. niger cells induced by 1% Avicel. First strand cDNA was synthesized from total RNA via reverse transcription. The full length cDNA of cbhB was amplified by PCR and cloned into the cloning vector, pGEM-T Easy. A comparison between genomic DNA and cDNA sequences of cbhB revealed that the gene is intronless. Upon the removal of the signal peptide, the cDNA of cbhB was cloned into the expression vector pET-32b. However, the recombinant CbhB was expressed in Escherichia coli Origami DE3 as an insoluble protein. A homology model of CbhB predicted the presence of nine disulfide bonds in the protein structure which may have contributed to the improper folding of the protein and thus, resulting in inclusion bodies in E. coli

  4. Growth Kinetics and Mechanistic Action of Reactive Oxygen Species Released by Silver Nanoparticles from Aspergillus niger on Escherichia coli

    Directory of Open Access Journals (Sweden)

    Shivaraj Ninganagouda

    2014-01-01

    Full Text Available Silver Nanoparticles (AgNPs, the real silver bullet, are known to have good antibacterial properties against pathogenic microorganisms. In the present study AgNPs were prepared from extracellular filtrate of Aspergillus niger. Characterization of AgNPs by UV-Vis spectrum reveals specific surface plasmon resonance at peak 416 nm; TEM photographs revealed the size of the AgNPs to be 20–55 nm. Average diameter of the produced AgNPs was found to be 73 nm with a zeta potential that was −24 mV using Malvern Zetasizer. SEM micrographs showed AgNPs to be spherical with smooth morphology. EDS revealed the presence of pure metallic AgNPs along with carbon and oxygen signatures. Of the different concentrations (0, 2.5, 5, 10, and 15 μg/mL used 10 μg/mL were sufficient to inhibit 107 CFU/mL of E. coli. ROS production was measured using DCFH-DA method and the the free radical generation effect of AgNPs on bacterial growth inhibition was investigated by ESR spectroscopy. This paper not only deals with the damage inflicted on microorganisms by AgNPs but also induces cell death through the production of ROS released by AgNPs and also growth kinetics of E. coli supplemented with AgNPs produced by A. niger.

  5. Optimization of the parameters for decolourization by Aspergillus niger of anaerobically digested distillery spentwash pretreated with polyaluminium chloride.

    Science.gov (United States)

    Singh, S S; Dikshit, A K

    2010-04-15

    Molasses spentwash from distilleries is characterized by high COD and colour. The fungal decolourization of anaerobically digested molasses spentwash requires significant dilution. In this study, decolourization by Aspergillus niger isolate IITB-V8 was performed on polyaluminium chloride (PAC) treated anaerobically digested spentwash without dilution of wastewater. Optimization of parameters was studied using statistical experimental designs. In the first step, Plackett-Burman design was used for screening the important parameters. Glucose was taken as the carbon source for the growth of A. niger. KH(2)PO(4) and pH were found to be the important factors affecting decolourization. In the second step, Box-Behnken design was used to determine the optimum level of each of the significant parameters. A second-order polynomial was determined by the multiple regression analysis of the experimental data. The optimum values for the important factors to achieve maximum decolourization of 68.4% were 5.5 g/L Glucose, 1.2 g/L KH(2)PO(4) and 5 pH. The determination coefficient (R(2)) was 0.9973, which ensures adequate credibility of the model. The total decolourization obtained after fungal treatment was 86.8% which indicates fungal decolourization after pretreatment with PAC is a viable option for the treatment of digested molasses spentwash. PMID:20022424

  6. Isolation, molecular cloning and expression of cellobiohydrolase B (CbhB) from Aspergillus niger in Escherichia coli

    Science.gov (United States)

    Woon, J. S. K.; Murad, A. M. A.; Abu Bakar, F. D.

    2015-09-01

    A cellobiohydrolase B (CbhB) from Aspergillus niger ATCC 10574 was cloned and expressed in E. coli. CbhB has an open reading frame of 1611 bp encoding a putative polypeptide of 536 amino acids. Analysis of the encoded polypeptide predicted a molecular mass of 56.2 kDa, a cellulose binding module (CBM) and a catalytic module. In order to obtain the mRNA of cbhB, total RNA was extracted from A. niger cells induced by 1% Avicel. First strand cDNA was synthesized from total RNA via reverse transcription. The full length cDNA of cbhB was amplified by PCR and cloned into the cloning vector, pGEM-T Easy. A comparison between genomic DNA and cDNA sequences of cbhB revealed that the gene is intronless. Upon the removal of the signal peptide, the cDNA of cbhB was cloned into the expression vector pET-32b. However, the recombinant CbhB was expressed in Escherichia coli Origami DE3 as an insoluble protein. A homology model of CbhB predicted the presence of nine disulfide bonds in the protein structure which may have contributed to the improper folding of the protein and thus, resulting in inclusion bodies in E. coli.

  7. Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of variants of monoamine oxidase from Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Atkin, Kate E. [Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5YW (United Kingdom); Reiss, Renate; Turner, Nicholas J. [School of Chemistry, Manchester Interdisciplinary Biocentre, University of Manchester, 131 Princess Street, Manchester M1 7DN (United Kingdom); Brzozowski, Andrzej M.; Grogan, Gideon, E-mail: grogan@ysbl.york.ac.uk [Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5YW (United Kingdom)

    2008-03-01

    Crystals of A. niger monoamine oxidase variants display P2{sub 1} or P4{sub 1}2{sub 1}2/P4{sub 3}2{sub 1}2 symmetry, with eight or two molecules in the asymmetric unit, respectively. Monoamine oxidase from Aspergillus niger (MAO-N) is an FAD-dependent enzyme that catalyses the conversion of terminal amines to their corresponding aldehydes. Variants of MAO-N produced by directed evolution have been shown to possess altered substrate specificity. Crystals of two of these variants (MAO-N-3 and MAO-N-5) have been obtained; the former displays P2{sub 1} symmetry with eight molecules per asymmetric unit and the latter has P4{sub 1}2{sub 1}2 or P4{sub 3}2{sub 1}2 symmetry and two molecules per asymmetric unit. Solution of these structures will help shed light on the molecular determinants of improved activity and high enantioselectivity towards a broad range of substrates.

  8. Efeito da toxicidade de Cr (VI e Zn (II no crescimento do fungo filamentoso Aspergillus niger isolado de efluente industrial Toxicity effect of Cr (VI and Zn (II on growth of filamentous fungi Aspergillus niger isolated from industrial effluent

    Directory of Open Access Journals (Sweden)

    Maria do Socorro Vale

    2011-09-01

    Full Text Available Processos convencionais de tratamento de efluentes utilizam microrganismos vivos, o que sugere limitações relativas À toxicidade de metais para os microrganismos. O experimento consistiu em adicionar soluções monoelementares de Cr (VI e Zn(II em diferentes concentrações (0, 20, 50, 100, 200, 300, 400, 500 mg.L-1 ao meio de crescimento e observar a influência dos metais no crescimento micelial e germinativo do fungo Aspergillus Níger por verificação visual da expansão radial do micélio e da germinação de esporos, seguida de registro fotográfico. Os resultados mostraram que o metabolismo do fungo foi completamente inibido em concentrações acima de 500 mg Zn (II.L-1 e 150 mg Cr (VI.L-1. O ED50 (concentração de ingrediente ativo capaz de inibir 50% do crescimento micelial do fungo para os dois íons metálicos, nas condições estudadas, está na faixa entre 100 e 150 mg.L-1. Palavras-chave: metais pesados; inibição; crescimento micelial; Aspergillus niger; ED50.Many standard processes of wastewater treatment use live microorganisms, which suggests limitations on a metal toxicity to the microorganism. The experiment consisted in adding mono elementary solutions of Cr (VI and Zn (II at different concentrations (0, 20, 50, 100, 200, 300, 400, 500 mg.L-1 to the growth mean, and to observe the influence of metals on mycelial and germinative growth of the Aspergillus niger fungus, by means of visual observation of the radial expansion of the mycelius and the germination of spores, followed by photograph registration. The results showed that the metabolism of the fungus was completely inhibited at concentrations above 500 mg Zn (II.L-1 and 150 mg Cr (VI.L-1. The ED50 (concentration of active ingredient capable of inhibiting 50% of mycelial growth of the fungus for both metal ions, under the studied conditions, is in the range between 100 and 150 mg.L-1.

  9. The 53-kDa proteolytic product of precursor starch-hydrolyzing enzyme of Aspergillus niger has Taka-amylase-like activity.

    Science.gov (United States)

    Ravi-Kumar, K; Venkatesh, K S; Umesh-Kumar, S

    2007-04-01

    The 53-kDa amylase secreted by Aspergillus niger due to proteolytic processing of the precursor starch-hydrolyzing enzyme was resistant to acarbose, a potent alpha-glucosidase inhibitor. The enzyme production was induced when A. niger was grown in starch medium containing the inhibitor. Antibodies against the precursor enzyme cross-reacted with the 54-kDa Taka-amylase protein of A. oryzae. It resembled Taka-amylase in most of its properties and also hydrolyzed starch to maltose of alpha-anomeric configuration. However, it did not degrade maltotriose formed during the reaction and was not inhibited by zinc ions. PMID:17123073

  10. AFM images of complexes between amylose and Aspergillus niger glucoamylase mutants, native and mutant starch binding domains: a model for the action of glucoamylase

    DEFF Research Database (Denmark)

    Morris, V. M.; Gunning, A. P.; Faults, C. B.;

    2005-01-01

    Atomic force microscopy has been used to investigate the complexes formed between high molecular weight amylose chains and Aspergillus niger glucoamylase mutants (E400Q and W52F), wild-type A. niger starch binding domains (SBDS), and mutant SBDs (W563K and W590K) lacking either of the two starch...... for the assembly of an expanded amylosic double helix. T his model for amylose-SBD binding has been used to propose a molecular mechanism for the role of the SBD in the hydrolytic action of glucoamylase on starch granules. The SBDs are considered to recognise the ends of amylosic double helices formed...

  11. Gene deletion of cytosolic ATP: citrate lyase leads to altered organic acid production in Aspergillus niger

    DEFF Research Database (Denmark)

    Meijer, Susan Lisette; Nielsen, Michael Lynge; Olsson, Lisbeth;

    2009-01-01

    factory platform for production of chemicals. Using molecular biology techniques, this study focused on metabolic engineering of A. niger to manipulate its organic acid production in the direction of succinic acid. The gene target for complete gene deletion was cytosolic ATP: citrate lyase (acl), which...

  12. Utilization of molasses and sugar cane bagasse for production of fungal invertase in solid state fermentation using Aspergillus niger GH1

    OpenAIRE

    F. Veana; J.L. Martínez-Hernández; Aguilar, C. N.; Rodríguez-Herrera, R.; G. Michelena

    2014-01-01

    Agro-industrial wastes have been used as substrate-support in solid state fermentation for enzyme production. Molasses and sugarcane bagasse are by-products of sugar industry and can be employed as substrates for invertase production. Invertase is an important enzyme for sweeteners development. In this study, a xerophilic fungus Aspergillus niger GH1 isolated of the Mexican semi-desert, previously reported as an invertase over-producer strain was used. Molasses from Mexico and Cuba were chemi...

  13. Hydrolysis of cellobiose by β-glucosidase from Aspergillus niger in the presence of soil solid phases: minerals, biochar, and activated carbon

    OpenAIRE

    Lammirato, Carlo

    2012-01-01

    This study investigates the effects of different soil solid phases on the extracellular enzymatic hydrolysis of cellobiose to glucose. Montmorillonite, kaolinite, goethite and wood char did not adsorb cellobiose whereas they adsorbed 10, 70, 70, 99 % respectively of β-glucosidase from Aspergillus niger. The hydrolysis rate decreased with increasing enzyme adsorption; wood char, for instance, reduced it by 30 %. Activated carbon adsorbed almost 100 % of both cellobiose and β-glucosidase and in...

  14. Characterization of β-Glucosidase Produced by Aspergillus niger under Solid-State Fermentation and Partially Purified Using MANAE-Agarose

    OpenAIRE

    Anderson Baraldo Junior; Borges, Diogo G.; Tardioli, Paulo W.; Farinas, Cristiane S.

    2014-01-01

    β -Glucosidase (BGL) is a hydrolytic enzyme with specificity for a wide variety of glycoside substrates, being an enzyme with a large range of biotechnological applications. However, enzyme properties can be different depending both on the microorganism and the cultivation procedure employed. Therefore, in order to explore potential biocatalytical applications of novel enzymes, their characterization is essential. In this work, a BGL synthesized by a selected strain of Aspergillus niger culti...

  15. Expression and secretion in Aspergillus nidulans and Aspergillus niger of a cell surface glycoprotein from the cattle tick, Boophilus microplus, by using the fungal amdS promoter system.

    OpenAIRE

    Turnbull, I F; Smith, D R; Sharp, P. J.; Cobon, G S; Hynes, M J

    1990-01-01

    A cell surface glycoprotein (Bm86) from cells of the digestive tract of the cattle tick Boophilus microplus, which has been shown to elicit a protective immunological response in vaccinated cattle, was expressed and secreted in the filamentous fungi Aspergillus nidulans and Aspergillus niger by using the fungal amdS promoter system. The cloned gene coded for the Bm86 secretory signal and all of the Bm86 mature polypeptide except for the hydrophobic carboxy-terminal segment. High levels of Bm8...

  16. Customization of Aspergillus niger Morphology Through Addition of Talc Micro Particles

    OpenAIRE

    Wucherpfennig, Thomas; Lakowitz, Antonia; Driouch, Habib; Krull, Rainer; Wittmann, Christoph

    2012-01-01

    The filamentous fungus A. niger is a widely used strain in a broad range of industrial processes from food to pharmaceutical industry. One of the most intriguing and often uncontrollable characteristics of this filamentous organism is its complex morphology. It ranges from dense spherical pellets to viscous mycelia (Figure 1). Various process parameters and ingredients are known to influence fungal morphology 1. Since optimal productivity correlates strongly with a specific morphological form...

  17. Simultaneous saccharification and fermentation of wheat bran flour into ethanol using coculture of amylotic Aspergillus niger and thermotolerant Kluyveromyces marxianus

    Institute of Scientific and Technical Information of China (English)

    K.MANIKANDAN; T.VIRUTHAGIRI

    2009-01-01

    Studies on simultaneous saccharification and fermentation (SSF) of wheat bran flour, a grain milling residue as the substrate using coculture method were carried out with strains of starch digesting Aspergillus niger and nonstarch digesting and sugar fermenting Kluyveromyces marxianus in batch fermentation. Experi-ments based on central composite design (CCD) were conducted to maximize the glucose yield and to study the effects of substrate concentration, pH, temperature, and enzyme concentration on percentage conversion of wheat bran flour starch to glucose by treatment with fungal α-amylase and the above parameters were optimized using response surface methodology (RSM). The optimum values of substrate concentration, pH, temperature, and enzyme concentration were found to be 200 g/L, 5.5, 65℃ and 7.5 IU, respectively, in the starch saccharification step. The effects of pH, temperature and substrate concentration on ethanol concentration, biomass and reducing sugar concentration were also investigated. The optimum temperature and pH were found to be 30℃ and 5.5, respectively. The wheat bran flour solution equivalent to 6% (w/V) initial starch concentration gave the highest ethanol concentration of 23.1 g/L after 48 h of fermentation at optimum conditions of pH and temperature. The growth kinetics was modeled using Monod model and Logistic model and product formation kinetics using Leudeking-Piret model. Simultaneous saccharificiation and fermenta-tion of liquefied wheat bran starch to bioethanol was studied using coculture of amylolytic fungus A. niger and nonamylolytic sugar fermenting K. marxianus.

  18. Proteomic analysis of the secretory response of Aspergillus niger to D-maltose and D-xylose.

    Directory of Open Access Journals (Sweden)

    José Miguel P Ferreira de Oliveira

    Full Text Available Fungi utilize polysaccharide substrates through extracellular digestion catalyzed by secreted enzymes. Thus far, protein secretion by the filamentous fungus Aspergillus niger has mainly been studied at the level of individual proteins and by genome and transcriptome analyses. To extend these studies, a complementary proteomics approach was applied with the aim to investigate the changes in secretome and microsomal protein composition resulting from a shift to a high level secretion condition. During growth of A. niger on D-sorbitol, small amounts of D-maltose or D-xylose were used as inducers of the extracellular amylolytic and xylanolytic enzymes. Upon induction, protein compositions in the extracellular broth as well as in enriched secretory organelle (microsomal fractions were analyzed using a shotgun proteomics approach. In total 102 secreted proteins and 1,126 microsomal proteins were identified in this study. Induction by D-maltose or D-xylose resulted in the increase in specific extracellular enzymes, such as glucoamylase A on D-maltose and β-xylosidase D on D-xylose, as well as of microsomal proteins. This reflects the differential expression of selected genes coding for dedicated extracellular enzymes. As expected, the addition of extra D-sorbitol had no effect on the expression of carbohydrate-active enzymes, compared to addition of D-xylose or D-maltose. Furthermore, D-maltose induction caused an increase in microsomal proteins related to translation (e.g., Rpl15 and vesicular transport (e.g., the endosomal-cargo receptor Erv14. Millimolar amounts of the inducers D-maltose and D-xylose are sufficient to cause a direct response in specific protein expression levels. Also, after induction by D-maltose or D-xylose, the induced enzymes were found in microsomes and extracellular. In agreement with our previous findings for D-xylose induction, D-maltose induction leads to recruitment of proteins involved in proteasome-mediated degradation.

  19. Role of glycosylation in the functional expression of an Aspergillus niger phytase (phyA) in Pichia pastoris.

    Science.gov (United States)

    Han, Y; Lei, X G

    1999-04-01

    Economical and thermostable phytase enzymes are needed to release phytate-phosphorus in plant foods for human and animal nutrition and to reduce phosphorus pollution of animal waste. Our objectives were to determine if a methylotrophic yeast, Pichia pastoris, was able to express a phytase gene (phyA) from Aspergillus niger efficiently and if suppression of glycosylation by tunicamycin affected its functional expression. The gene (1.4 kb) was inserted into an expression vector pPICZalphaA with a signal peptide alpha-factor, under the control of AOX1 promoter. The resulting plasmid was transformed into two P. pastoris strains: KM71 (methanol utilization slow) and X33 (wild-type). Both host strains produced high levels of active phytase (25-65 units/ml of medium) that were largely secreted into the medium. The expressed enzyme was cross-reacted with the polyclonal antibody raised against the wild-type enzyme and showed two pH optima, 2.5 and 5.5, and an optimal temperature at 60 degrees C. Compared with the phyA phytase overexpressed by A. niger, this phytase had identical capacity in hydrolyzing phytate-phosphorus from soybean meal and slightly better thermostability. Deglycosylation of the secreted phytase resulted in reduction in the size from 95 to 55 kDa and in thermostability by 34%. Tunicamycin (20 microg/ml of medium) resulted in significant reductions of both intracellular and extracellular phytase activity expression. Because there was no accumulation of intracellular phytase protein, the impairment did not seem to occur at the level of translocation of phytase. In conclusion, glycosylation was vital to the biosynthesis of the phyA phytase in P. pastoris and the thermostability of the expressed enzyme. PMID:10087168

  20. Adaptive melanin response of the soil fungus Aspergillus niger to UV radiation stress at "Evolution Canyon", Mount Carmel, Israel.

    Directory of Open Access Journals (Sweden)

    Natarajan Singaravelan

    Full Text Available BACKGROUND: Adaptation is an evolutionary process in which traits in a population are tailored by natural selection to better meet the challenges presented by the local environment. The major discussion relating to natural selection concerns the portraying of the cause and effect relationship between a presumably adaptive trait and selection agents generating it. Therefore, it is necessary to identify trait(s that evolve in direct response to selection, enhancing the organism's fitness. "Evolution Canyon" (EC in Israel mirrors a microcosmic evolutionary system across life and is ideal to study natural selection and local adaptation under sharply, microclimatically divergent environments. The south-facing, tropical, sunny and xeric "African" slope (AS receives 200%-800% higher solar radiation than the north-facing, temperate, shady and mesic "European" slope (ES, 200 meters apart. Thus, solar ultraviolet radiation (UVR is a major selection agent in EC influencing the organism-environment interaction. Melanin is a trait postulated to have evolved for UV-screening in microorganisms. Here we investigate the cause and effect relationship between differential UVR on the opposing slopes of EC and the conidial melanin concentration of the filamentous soil fungus Aspergillus niger. We test the working hypothesis that the AS strains exhibit higher melanin content than strains from the ES resulting in higher UV resistance. METHODOLOGY/PRINCIPAL FINDINGS: We measured conidial melanin concentration of 80 strains from the EC using a spectrophotometer. The results indicated that mean conidial melanin concentration of AS strains were threefold higher than ES strains and the former resisted UVA irradiation better than the latter. Comparisons of melanin in the conidia of A. niger strains from sunny and shady microniches on the predominantly sunny AS and predominantly shady ES indicated that shady conditions on the AS have no influence on the selection on melanin

  1. Isolation and optimization of pectinase enzyme production one of useful industrial enzyme in Aspergillus niger, Rhizopus oryzae, Penicilium chrysogenum

    Directory of Open Access Journals (Sweden)

    akram songol

    2016-06-01

    Full Text Available Introduction: Pectinase enzyme is one of the most important industrial enzymes which isolated from a wide variety of microorganisms such as bacteria and filamentous fungi. This enzyme has been usually used in the fruit and textile industry. In this study, the isolation and optimization of pectinase-producing fungi on decaying rotten fruits were studied. Materials and methods: Isolation and screening of pectinase producing fungi performed through plate culture on pectin medium and staining with Lugol's iodine solution. The best strains were identified by ITS1, 4 sequencing as Aspergillus fumigatus, Rhizopus oryzae, Penicilium chrysogenum. The enzyme production was optimized by application of the five factorial design, each at three levels. These factors are carbon sources (whey, glucose and stevia, ammonium sulfate, manganese sulfate, temperature, and pH. Pectinase concentration was measured by the Miller method. Results: The results indicate that optimum condition for enzyme production for three fungi strains was obtained at 32 °C, pH = 6, 3g / L manganese sulfate, 2.75g / L of ammonium sulfate and 10g / L of each carbon source. The best experiment in obtaining the optimum enzyme contained 1.328 mg / ml of glucose for Aspergillus niger 1.284 and 1.039 mg / ml of whey for Rhizopus oryzae and Penicilium chrysogenum. Molecular weight of enzyme was about 40 and 37 kDa which was obtained by SDS- PAGE. Discussion and conclusion: The results indicate that three strains could grow in a wide range of carbon source, pH and temperature, which could be a good candidate for industrial application.

  2. Primary cutaneous aspergillosis due to Aspergillus niger in an immunocompetent patient

    Directory of Open Access Journals (Sweden)

    Mohapatra S

    2009-01-01

    Full Text Available Primary cutaneous aspergillosis is a rare entity, usually caused by A. fumigatus and A. flavus . Here, we present such a case, manifested by ulceration due to A. niger, which remained undiagnosed for a prolonged period. The immunological status was intact, although the patient had associated severe fungal infection. Recurrence of the lesion occurred despite repeated anti-fungal therapies. Anti fungal testing was done based on the broth dilution (M-38A, NCCLS, USA method. The culture isolate was found to be sensitive to fluconazole and amphotericin B. Continuation of antifungal therapy improved the symptoms, reducing the size of the lesion.

  3. Citric Acid Production by the Aspergillus niger Isolated from the Microflora of Iran

    OpenAIRE

    R. Yazdanparast; and A. Bahrani

    1995-01-01

    Citric acid production by A.niger, isolated from the microflora of Iran, has been investigated in liquid and semi-solid states using growth media with different compositions. In 2% media made of Rocheh grape pomace or sabouraud dextrose, the yield of citric acid production was 0.7 g per Kg of the pomace; and the yield decreased by 50% in 2% saghal solian grape pomace medium. However, in 40% (W/W) saghal solian semi-solid medium containing 3% methanol, the yield of citric acid production has i...

  4. Biotransformation of natural compounds: unexpected thio conjugation of Sch-642305 with 3-mercaptolactate catalyzed by Aspergillus niger ATCC 16404 cells.

    Science.gov (United States)

    Adelin, Emilie; Martin, Marie-Thérèse; Bricot, Marie-Françoise; Cortial, Sylvie; Retailleau, Pascal; Ouazzani, Jamal

    2012-12-01

    Sch-642305 is produced by the endophytic fungi Phomopsis sp. CMU-LMA and exhibits both antimicrobial and cytotoxic activities. The incubation of Sch-642305 with Aspergillus niger ATCC 16404 resting cells leads to two unexpected thio conjugates. Compound (1) is formed by the addition of the cysteine metabolite 3-mercaptolactate to the double bond of Sch-642305. Compound (1) undergoes an intramolecular rearrangement to give compound (2), which contains two rings: a five-membered hydroxylactone ring and a five-membered thiophene ring. The absolute configuration of compound (1) is similar to that of the parent compound, but the configuration of the mercaptolactate side-chain was not determined. The absolute configuration of compound (2) was deduced from the crystal structure and confirmed by the anomal effect of the sulfur atom. To the best of our knowledge, this is the first time such a conjugation rearrangement reactions were observed. The biological significance and the reaction mechanisms are discussed. Compound (1) exhibits a weak antimicrobial activity against Gram-positive bacteria, whereas derivatives (1) and (2) showed an IC₅₀ of 1 and 1.2 μM, respectively, against colonic epithelial cancer cells. PMID:22975164

  5. Secretory Expression and Characterization of an Acidic Endo-Polygalacturonase Gene from Aspergillus niger SC323 in Saccharomyces cerevisiae.

    Science.gov (United States)

    Zhou, Huoxiang; Li, Xi; Guo, Mingyue; Xu, Qingrui; Cao, Yu; Qiao, Dairong; Cao, Yi; Xu, Hui

    2015-07-01

    The endo-polygalacturonase gene (endo-pgaA) was cloned from DNA of Aspergillus niger SC323 using the cDNA synthesized by overlapping PCR, and successfully expressed in Saccharomyces cerevisiae EBY100 through fusing the α-factor signal peptide of yeast. The full-length cDNA consists of 1,113 bp and encodes a protein of 370 amino acids with a calculated molecular mass of 38.8 kDa. After induction by galactose for 48 h, the activity of recombinant endo-PgaA in the culture supernatant can reach up to 1,448.48 U/mg. The recombinant protein was purified to homogeneity by ammonium sulfate precipitation and gel filtration column chromatography and subsequently characterized. The optimal pH and temperature of the purified recombinant enzyme were 5.0 and 50°C, respectively. The Michaelis-Menten constant (Km) and maximal velocity (Vmax) of the enzyme for pectin were 88.54 μmol/ml and 175.44 μmol/mg/min, respectively. The enzyme activity was enhanced by Ca(2+), Cu(2+), and Na(+), and strongly inhibited by Pb(2+) and Mn(2+). The pectin hydrolysates were mainly galacturonic acid and other oligo-galacturonates. Therefore, these characteristics suggest that the recombinant endo-PgaA may be of potential use in the food and feed industries. PMID:25737122

  6. Phenotypic characterization of Aspergillus niger and Candida albicans grown under simulated microgravity using a three-dimensional clinostat.

    Science.gov (United States)

    Yamazaki, Takashi; Yoshimoto, Maki; Nishiyama, Yayoi; Okubo, Yoichiro; Makimura, Koichi

    2012-07-01

    The living and working environments of spacecraft become progressively contaminated by a number of microorganisms. A large number of microorganisms, including pathogenic microorganisms, some of which are fungi, have been found in the cabins of space stations. However, it is not known how the characteristics of microorganisms change in the space environment. To predict how a microgravity environment might affect fungi, and thus how their characteristics could change on board spacecraft, strains of the pathogenic fungi Aspergillus niger and Candida albicans were subjected to on-ground tests in a simulated microgravity environment produced by a three-dimensional (3D) clinostat. These fungi were incubated and cultured in a 3D clinostat in a simulated microgravity environment. No positive or negative differences in morphology, asexual reproductive capability, or susceptibility to antifungal agents were observed in cultures grown under simulated microgravity compared to those grown in normal earth gravity (1 G). These results strongly suggest that a microgravity environment, such as that on board spacecraft, allows growth of potentially pathogenic fungi that can contaminate the living environment for astronauts in spacecraft in the same way as they contaminate residential areas on earth. They also suggest that these organisms pose a similar risk of opportunistic infections or allergies in astronauts as they do in people with compromised immunity on the ground and that treatment of fungal infections in space could be the same as on earth. PMID:22537211

  7. Effects of inclusion Aspergillus niger fermented shrimp waste meal in broiler diets on live performance and digestive organ weight

    Directory of Open Access Journals (Sweden)

    Irfan H. Djunaidi

    2009-06-01

    Full Text Available An experiment was conducted to evaluate the effect of the inclusion of different levels of shrimp waste meal fermented with Aspergillus niger (LUF in diets on growth performance and digestive organ weight of broilers. A total of 75 d-old chicks were randomly allocated to 5 (five treatments in 3 replication pens of 5 birds each. Treatments consisted of LUF inclusion of 0 (control, and 5, 7.5, 10 and 12,5% (P0, P1, P2, P3 and P4 in the diets. Birds were raised under standard condition and provided with feed and water ad-libitum. Feed and birds were weighed weekly up to 35 days to determine body weight, feed intake and feed conversion. At the end of experimental period, the birds were slaughatered and dressed up to determine carcass percentage and digestive organ weight. There was a significant negative linear response in body weight, feed consumption and feed conversion with increase of LUF more than 7.5% in the diets until 35 days of age, but % carcass was almost the same for all treatment. There was no significant response in digestive organ weight with increasing levels of LUF. The present result indicated that LUF could be considered as a potential feed ingredient as protein source of broiler but its inclusion should be limited until 7.5% of the diet to maintain growth performance and digestive organ weight.

  8. Optimization of cultural conditions for the production of alpha amylase by aspergillus niger (btm-26) in solid state fermentation

    International Nuclear Information System (INIS)

    The present study deals with the isolation, screening and selection of native fungal strain for the alpha amylase production. Forty fungal strains were isolated from different soil samples. These strains were initially screened qualitatively on starch agar medium and quantitative screening was carried out in solid state fermentation. A strain of Aspergillus niger showing maximum production (432 +- 0.9 U/ml/min) of enzyme was selected and assigned the code BTM-26. The yield on various agricultural products, namely, coconut oil cake (COC), rice bran (RB), vegetable wastes or banana peel and wheat bran (WB) was compared. Wheat bran proved to be the best substrate for alpha amylase production. The effect of incubation temperature, initial pH, and inoculum size was investigated for the enzyme production. The maximum enzyme production was obtained at 30 degree C, pH 5, and inoculum size of 1 ml. The rate of fermentation was also studied and the highest yield of enzyme was obtained after 72 h of inoculation. Addition of 1.5% lactose as carbon source and 0.2% (NH/sub 4/)2SO/sub 4/ and 0.3% yeast extract as inorganic and organic nitrogen sources respectively gave enzyme production 990 +- 0.81 U/ml/min which reflects about 1.87 fold increase in alpha amylase production as compared to the medium containing wheat bran alone as substrate. (author)

  9. A study of organic acid production in contrasts between two phosphate solubilizing fungi: Penicillium oxalicum and Aspergillus niger

    Science.gov (United States)

    Li, Zhen; Bai, Tongshuo; Dai, Letian; Wang, Fuwei; Tao, Jinjin; Meng, Shiting; Hu, Yunxiao; Wang, Shimei; Hu, Shuijin

    2016-01-01

    Phosphate solubilizing fungi (PSF) have huge potentials in enhancing release of phosphorus from fertilizer. Two PSF (NJDL-03 and NJDL-12) were isolated and identified as Penicillium oxalicum and Aspergillus niger respectively in this study. The quantification and identification of organic acids were performed by HPLC. Total concentrations of organic acids secreted by NJDL-03 and NJDL-12 are ~4000 and ~10,000 mg/L with pH values of 3.6 and 2.4 respectively after five-days culture. Oxalic acid dominates acidity in the medium due to its high concentration and high acidity constant. The two fungi were also cultured for five days with the initial pH values of the medium varied from 6.5 to 1.5. The biomass reached the maximum when the initial pH values are 4.5 for NJDL-03 and 2.5 for NJDL-12. The organic acids for NJDL-12 reach the maximum at the initial pH = 5.5. However, the acids by NJDL-03 continue to decrease and proliferation of the fungus terminates at pH = 2.5. The citric acid production increases significantly for NJDL-12 at acidic environment, whereas formic and oxalic acids decrease sharply for both two fungi. This study shows that NJDL-12 has higher ability in acid production and has stronger adaptability to acidic environment than NJDL-03. PMID:27126606

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

    DEFF Research Database (Denmark)

    Pedersen, Henrik; Beyer, Michael; Nielsen, Jens

    2000-01-01

    The Aspergillus niger strain BO-1 was grown in batch, continuous (chemostat) and fed-batch cultivations in order to study the production of the extracellular enzyme glucoamylase under different growth conditions. In the pH range 2.5-6.0, the specific glucoamylase productivity and the specific...... growth rate of the fungus were independent of pH when grown in batch cultivations. The specific glucoamylase productivity increased linearly with the specific growth rate in the range 0-0.1 h(-1) and was constant in the range 0.1-0.2 h(-1) Maltose and maltodextrin were non-inducing carbon sources...... compared to glucose, and the maximum specific growth rate was 0.19 +/- 0.02 h(-1) irrespective of whether glucose or maltose was the carbon source. In fed-batch cultivations, glucoamylase titres of up to 6.5 g 1(-1) were obtained even though the strain contained only one copy of the glaA gene....

  11. Immobilization of Aspergillus niger F7-02 Lipase in Polysaccharide Hydrogel Beads of Irvingia gabonensis Matrix.

    Science.gov (United States)

    Kareem, Safaradeen Olateju; Adio, Olayinka Quadri; Osho, Michael Bamitale

    2014-01-01

    The potential of polysaccharide Irvingia gabonensis matrix as enzyme immobilization support was investigated. Lipase of Aspergillus niger F7-02 was immobilized by entrapment using glutaraldehyde as the cross-linking agent and stabilized in ethanolic-formaldehyde solution. The pH and temperature stability and activity yield of the immobilized enzyme were determined. Such parameters as enzyme load, bead size, number of beads, and bead reusability were also optimized. Adequate gel strength to form stabilized beads was achieved at 15.52% (w/v) Irvingia gabonensis powder, 15% (v/v) partially purified lipase, 2.5% (v/v) glutaraldehyde, and 3 : 1 (v/v) ethanolic-formaldehyde solution. There was 3.93-fold purification when the crude enzyme was partially purified in two-step purification using Imarsil and activated charcoal. Optimum lipase activity 75.3 Ug(-1) was achieved in 50 mL test solution containing 15 beads of 7 mm bead size. Relative activity 80% was retained at eight repeated cycles. The immobilization process gave activity yield of 59.1% with specific activity of 12.3 Umg(-1) and stabilized at optimum pH 4.5 and temperature 55°C. Thus the effectiveness and cost-efficiency of I. gabonensis as a polymer matrix for lipase immobilization have been established. PMID:25614829

  12. Purification and Characterization of a Lipase with High Thermostability and Polar Organic Solvent-Tolerance from Aspergillus niger AN0512.

    Science.gov (United States)

    Liu, Guang; Hu, Songqing; Li, Lin; Hou, Yi

    2015-11-01

    An extracellular lipase (EC 3.1.1.3, AN0512Lip) from Aspergillus niger AN0512 was purified and its characteristics were investigated. After the process of ammonium sulfate precipitation followed by ion-exchange chromatography and gel filtration, the purified lipase was achieved with 203.6-fold purification and 22.1 % recovery. AN0512Lip exhibited the highest activity at 50 °C and pH 5.0. It was thermostable and pH-stable, as indicated by that more than 50 % activity retained at 60 °C for 20 h and more than 90 % activity retained at pH 3.0 for 20 h, respectively. AN0512Lip activity was stimulated by some divalent metal ions (especially Cu(2+), Ca(2+)), while greatly suppressed by EDTA, indicating that AN0512Lip was a metal-activated enzyme. Moreover, AN0512Lip exhibited high tolerance for various polar organic solvents with log P isopropanol to the reaction mixture. AN0512Lip also displayed 3-regiospecificity and great affinity for the long-chain fatty ester. The preliminary test showed that AN0512Lip was a candidate for enriching EPA and DHA in fish oil. All the unique properties, such as thermostability, Cu(2+)-dependent, 3-regiospecificity, and polar organic solvent-tolerance, indicated that AN0512Lip could have potential applications in the food industry, even in organic synthesis and the pharmaceutical industry. PMID:26216145

  13. Functional and structural analysis of Pichia pastoris-expressed Aspergillus niger 1,4-β-endoglucanase.

    Science.gov (United States)

    Yan, Junjie; Liu, Weidong; Li, Yujie; Lai, Hui-Lin; Zheng, Yingying; Huang, Jian-Wen; Chen, Chun-Chi; Chen, Yun; Jin, Jian; Li, Huazhong; Guo, Rey-Ting

    2016-06-17

    Eukaryotic 1,4-β-endoglucanases (EC 3.2.1.4) have shown great potentials in many commercial applications because they effectively catalyze hydrolysis of cellulose, the main component of the plant cell wall. Here we expressed a glycoside hydrolase family (GH) 5 1,4-β-endoglucanase from Aspergillus niger (AnCel5A) in Pichia pastoris, which exhibits outstanding pH and heat stability. In order to further investigate the molecular mechanism of AnCel5A, apo-form and cellotetraose (CTT) complex enzyme crystal structures were solved to high resolution. AnCel5A folds into a typical (β/α)8-TIM barrel architecture, resembling other GH5 members. In the substrate binding cavity, CTT is found to bind to -4 - -1 subsites, and several polyethylene glycol molecules are found in positive subsites. In addition, several unique N-glycosylation motifs that may contribute to protein higher stability were observed from crystal structures. These results are of great importance for understanding the molecular mechanism of AnCel5A, and also provide guidance for further applications of the enzyme. PMID:27154222

  14. Probing role of key residues in the divergent evolution of Yarrowia lipolytica lipase 2 and Aspergillus niger eruloyl esterase A.

    Science.gov (United States)

    Wang, Guilong; Liu, Zimin; Xu, Li; Zhang, Houjin; Yan, Yunjun

    2015-09-01

    Yarrowia lipolytica lipase 2 (YLLip2) and Aspergillus niger feruloyl esterase A (AnFaeA) are enzymes of similar structures but with different functions. They are both classified into the same homologous family in Lipase Engineering Database (LED). The major difference between the two enzymes is that YLLip2 exhibits interfacial activity while AnFaeA does not. In order to better understand the interfacial activation mechanisms of YLLip2, structure guided site-directed mutagenesis were performed, mutants were constructed, kinetics parameters and lipase properties were detected. Mutant enzymes showed enhanced catalytic efficiency towards p-nitrophenyl butyrin (pNPB) but their catalytic efficiency decreased towards p-nitrophenyl palmitate (pNPP), their catalysis behavior was more close to feruloyl esterase. Moreover, the mutant enzymes exhibited enhanced thermostability compared with their wild type. These results indicate that I100 and F129 are probably cut-off point of divergent functions between the two enzymes during evolution. PMID:26302844

  15. Purification and Characterization of a Ginsenoside Rb1-Hydrolyzing β-Glucosidase from Aspergillus niger KCCM 11239

    Directory of Open Access Journals (Sweden)

    Kyung Hoon Chang

    2012-09-01

    Full Text Available Rb1-hydrolyzing β-glucosidase from Aspergillus niger KCCM 11239 was studied to develop a bioconversion process for minor ginsenosides. The specific activity of the purified enzyme was 46.5 times greater than that of the crude enzyme. The molecular weight of the native enzyme was estimated to be approximately 123 kDa. The optimal pH of the purified enzyme was pH 4.0, and the enzyme proved highly stable over a pH range of 5.0–10.0. The optimal temperature was 70 °C, and the enzyme became unstable at temperatures above 60 °C. The enzyme was inhibited by Cu2+, Mg2+, Co2+, and acetic acid (10 mM. In the specificity tests, the enzyme was found to be active against ginsenoside Rb1, but showed very low levels of activity against Rb2, Rc, Rd, Re, and Rg1. The enzyme hydrolyzed the 20-C,β-(1→6-glucoside of ginsenoside Rb1 to generate ginsenoside Rd and Rg3, and hydrolyzed 3-C,β-(1→2-glucoside to generate F2. The properties of the enzyme indicate that it could be a useful tool in biotransformation applications in the ginseng industry, as well as in the development of novel drug compounds.

  16. Characterization of β -Glucosidase Produced by Aspergillus niger under Solid-State Fermentation and Partially Purified Using MANAE-Agarose.

    Science.gov (United States)

    Baraldo Junior, Anderson; Borges, Diogo G; Tardioli, Paulo W; Farinas, Cristiane S

    2014-01-01

    β -Glucosidase (BGL) is a hydrolytic enzyme with specificity for a wide variety of glycoside substrates, being an enzyme with a large range of biotechnological applications. However, enzyme properties can be different depending both on the microorganism and the cultivation procedure employed. Therefore, in order to explore potential biocatalytical applications of novel enzymes, their characterization is essential. In this work, a BGL synthesized by a selected strain of Aspergillus niger cultivated under solid-state fermentation (SSF) was partially purified and fully characterized in terms of optimum pH, temperature, and thermostability. The single-step purification using MANAE-agarose in a chromatographic column yielded an enzyme solution with specific activity (17.1 IU/mg protein) adequate for the characterization procedures. Electrophoresis SDS-PAGE and size-exclusion chromatography analysis resulted in an estimated molecular mass of 60 kDa. Higher enzyme activities were found in the range between 40 and 65°C and between pH 4 and 5.5, indicating an interesting characteristic for application in the hydrolysis of lignocellulosic biomass for biofuels production. Thermostability studies of purified BGL resulted in half-lives at 37°C of 56.3 h and at 50°C of 5.4 h. These results provide support for further studies of this enzyme towards revealing its potential biotechnological applications. PMID:24940510

  17. Downstream processing of pectinase produced by Aspergillus niger in solid state cultivation and its application to fruit juices clarification

    Directory of Open Access Journals (Sweden)

    Patrícia Poletto

    2015-06-01

    Full Text Available In this work, a protocol for the formulation of an enzyme concentrated product to be applied in fruit juice treatment is described. Downstream processing conditions for the recovery and concentration of pectinases produced by the new strain Aspergillus niger LB-02-SF in solid state cultivation were assessed. The solid-liquid ratio in the extraction step of pectinases recovery from the cultivated media was evaluated and the highest activity was obtained with a solid-liquid ratio of 1:10. The crude extract was concentrated by ultrafiltration and the total pectinase (TP activity was 73.6-fold concentrated in relation to the crude extract, and a final TP titer of 663 U mL–1 was obtained with 73.7% of recovery yield. KCl and different glycerol concentrations were added to the concentrated extract and the stability of pectinases during the storage at 5°C for 59 weeks was tested. The formulation with 50% w/w glycerol was applied to the treatment of apple and grape juices and the results of these tests were statistically comparable to those obtained with two high-quality commercial preparations.

  18. Immobilization of Aspergillus niger F7-02 Lipase in Polysaccharide Hydrogel Beads of Irvingia gabonensis Matrix

    Directory of Open Access Journals (Sweden)

    Safaradeen Olateju Kareem

    2014-01-01

    Full Text Available The potential of polysaccharide Irvingia gabonensis matrix as enzyme immobilization support was investigated. Lipase of Aspergillus niger F7-02 was immobilized by entrapment using glutaraldehyde as the cross-linking agent and stabilized in ethanolic-formaldehyde solution. The pH and temperature stability and activity yield of the immobilized enzyme were determined. Such parameters as enzyme load, bead size, number of beads, and bead reusability were also optimized. Adequate gel strength to form stabilized beads was achieved at 15.52% (w/v Irvingia gabonensis powder, 15% (v/v partially purified lipase, 2.5% (v/v glutaraldehyde, and 3 : 1 (v/v ethanolic-formaldehyde solution. There was 3.93-fold purification when the crude enzyme was partially purified in two-step purification using Imarsil and activated charcoal. Optimum lipase activity 75.3 Ug−1 was achieved in 50 mL test solution containing 15 beads of 7 mm bead size. Relative activity 80% was retained at eight repeated cycles. The immobilization process gave activity yield of 59.1% with specific activity of 12.3 Umg−1 and stabilized at optimum pH 4.5 and temperature 55°C. Thus the effectiveness and cost-efficiency of I. gabonensis as a polymer matrix for lipase immobilization have been established.

  19. SCANNING ELECTRON MICROSCOPY (SEM) FOR THE BIOAGENTS ASPERGILLUS NIGER AND PENICILLIUM OXALICUM AGAINST THE MEDITERRANEAN FRUIT FLY, CERATITIS CAPITATA (WIED.)

    International Nuclear Information System (INIS)

    As an alternative to chemical control or as a part of integrated pest management (IPM program), there is a resurgence of interest in using microbial agents for pest population suppression before the application of the sterile insect technique (SIT) against the Mediterranean fruit fly, Ceratitis capitata (Wiedmann). The insect-fungus interaction between the fungal isolates, Aspergillus niger and Penicillium oxalicum, when applied as a spore suspension against the adults of Medfly in the laboratory showed visual fungal development after 7 days from inoculation. Examination of the infected parts of the dead fly with light microscopy showed a markedly damage as evidenced by the occurrence of the attached conidia and features of pathogen penetration. Using the scanning electron microscopy (SEM), the abundant sporulation of both fungal isolates was investigated over all parts of the dead fly and their associated sensillae. The recognized shape of the fungal conidial spores and their arrangement on the hyphae of both bio agents was investigated. This ultra structural study may be helpful in evaluating the effectiveness of both fungal bio agents on the functions of all infected parts of the insect and their associated sensillae (the main communication system between insects, their internal and external environment) and their main role in the courtship, male mating ability, the selection of fruit host plants necessary for the adults food and also the selection of a suitable oviposition site

  20. Hemicellulase production by Aspergillus niger DSM 26641 in hydrothermal palm oil empty fruit bunch hydrolysate and transcriptome analysis.

    Science.gov (United States)

    Ottenheim, Christoph; Verdejo, Carl; Zimmermann, Wolfgang; Wu, Jin Chuan

    2014-12-01

    Palm oil empty fruit bunches (EFB) is an abundant and cheap lignocellulose material in Southeast Asia. Its use as the sole medium for producing lignocellulose-hydrolyzing enzymes would increase its commercial value. A newly isolated Aspergillus niger DSM 26641 was investigated for its capability of producing hemicellulases in EFB hydrolysate obtained by treatment with pressurized hot water (1-20%, w/v) at 120-180°C in a 1 L Parr reactor for 10-60 min. The optimal hydrolysate for the fungal growth and endoxylanase production was obtained when 10% (w/v) of empty fruit bunch was treated at 120°C or 150°C for 10 min, giving an endoxylanase activity of 24.5 mU ml(-1) on RBB-Xylan and a saccharification activity of 5 U ml(-1) on xylan (DNS assay). When the hydrolysates were produced at higher temperatures, longer treatment times or higher biomass contents, only less than 20% of the above maximal endoxylanase activity was detected, possibly due to the higher carbohydrate concentrations in the medium. Transcriptome analysis showed that 3 endoxylanases (expression levels 59-100%, the highest level was set as 100%), 2 β-xylosidases (4%), 4 side chain-cleaving arabinofuranosidases (1-95%), 1 acetyl xylan esterase (9%) and 2 ferulic acid esterases (0.3-9%) were produced together. PMID:24958131

  1. PRODUCTION OF LIPASES IN SOLID-STATE FERMENTATION BY Aspergillus niger F7-02 WITH AGRICULTURAL RESIDUES

    Directory of Open Access Journals (Sweden)

    Olayinka Quadri Adio

    2015-06-01

    Full Text Available In this study mould strains screened and molecularly identified as Aspergillus niger F7-02 was used to produced extracellular lipase in Solid State Fermentation (SSF process. Different agricultural residues were combined in different ratios as carbon, nitrogen and elemental sources in the solid culture medium. The optimization of the culture medium was carried out for such parameters as incubation time (24 h - 96 h, inoculum concentration (0.5 – 3.0%, w/v, initial moisture content (40 – 70%, w/v, and initial pH (6 – 8 for maximum yield. The maximum lipase activity of 76.7 U/ml was obtained with a medium containing rice bran (RB, palm kernel cake (PKC, groundnut cake (GNC and starch (S at the ratio of 5:5:3:1 (%w/w with optimum conditions of 60% moisture, 1% inoculum and a pH of 7.0 with an incubation temperature of 30 oC and incubation time of 72 h.

  2. Bioleaching of incineration fly ash by Aspergillus niger – precipitation of metallic salt crystals and morphological alteration of the fungus

    Directory of Open Access Journals (Sweden)

    Tong-Jiang Xu

    2014-09-01

    Full Text Available This study examines the bioleaching of municipal solid waste incineration fly ash by Aspergillus niger, and its effect on the fungal morphology, the fate of the ash particles, and the precipitation of metallic salt crystals during bioleaching. The fungal morphology was significantly affected during one-step and two-step bioleaching; scanning electron microscopy revealed that bioleaching caused distortion of the fungal hyphae (with up to 10 μm hyphae diameter and a swollen pellet structure. In the absence of the fly ash, the fungi showed a linear structure (with 2–4 μm hyphae diameter. Energy-dispersive X-ray spectroscopy and X-ray diffraction confirmed the precipitation of calcium oxalate hydrate crystals at the surface of hyphae in both one-step and two-step bioleaching. Calcium oxalate precipitation affects bioleaching via the weakening of the fly ash, thus facilitating the release of other tightly bound metals in the matrix.

  3. Study of a High-Yield Cellulase System Created by Heavy-Ion Irradiation-Induced Mutagenesis of Aspergillus niger and Mixed Fermentation with Trichoderma reesei.

    Directory of Open Access Journals (Sweden)

    Shu-Yang Wang

    Full Text Available The aim of this study was to evaluate and validate the efficiency of 12C6+ irradiation of Aspergillus niger (A. niger or mutagenesis via mixed Trichoderma viride (T. viride culturing as well as a liquid cultivation method for cellulase production via mixed Trichoderma reesei (T. reesei and A. niger culture fermentation. The first mutagenesis approach was employed to optimize yield from a cellulase-producing strain via heavy-ion mutagenesis and high-throughput screening, and the second was to effectively achieve enzymatic hydrolysis of cellulase from a mixed culture of mutant T. viride and A. niger. We found that 12C6+-ion irradiation induced changes in cellulase biosynthesis in A. niger but had no effect on the time course of the synthesis. It is notable that the exoglucanases (CBH activities of A. niger strains H11-1 and H differed (6.71 U/mL vs. 6.01 U/mL and were significantly higher than that of A. niger mutant H3-1. Compared with strain H, the filter paper assay (FPA, endoglucanase (EG and β-glucosidase (BGL activities of mutant strain H11-1 were increased by 250.26%, 30.26% and 34.91%, respectively. A mixed culture system was successfully optimized, and the best ratio of T. reesei to A. niger was 5:1 for 96 h with simultaneous inoculation. The BGL activity of the mixed culture increased after 72 h. At 96 h, the FPA and BGL activities of the mixed culture were 689.00 and 797.15 U/mL, respectively, significantly higher than those of monocultures, which were 408.70 and 646.98 U/mL for T. reesei and 447.29 and 658.89 U/mL for A. niger, respectively. The EG activity of the mixed culture was 2342.81 U/mL, a value that was significantly higher than that of monocultures at 2206.57 U/mL for T. reesei and 1727.62 U/mL for A. niger. In summary, cellulose production and hydrolysis yields were significantly enhanced by the proposed combination scheme.

  4. 黑曲霉Aspergillus niger P-6021浆态发酵常山胡柚皮渣产果胶霉%Pectinase Production by Aspergillus Niger P-6021 on Citrus Changshan-huyou Peel in Slurry-state Fermentation

    Institute of Scientific and Technical Information of China (English)

    钟卫鸿; 岑沛霖

    2005-01-01

    The peel of Citrus changshan-huyou, coupled with wheat bran, could be utilized by Aspergillus niger P-6021 in slurry-state fermentation to produce pectinase with suitable enzyme composition for application in apple juice processing. The production of pectinase is improved by additional nitrogen source substances and mineral supplements. The ratio of carbon source substances to nitrogen source substances in the medium also has significant effect on the pectinase production by A. niger P-6021 in slurry-state fermentation. In the optimized medium 30℃. The crude pectinase shows significant effect to improve the yield and clarification of apple juice.

  5. Citric Acid Production by the Aspergillus niger Isolated from the Microflora of Iran

    Directory of Open Access Journals (Sweden)

    R.Yazdanparast

    1995-08-01

    Full Text Available Citric acid production by A.niger, isolated from the microflora of Iran, has been investigated in liquid and semi-solid states using growth media with different compositions. In 2% media made of Rocheh grape pomace or sabouraud dextrose, the yield of citric acid production was 0.7 g per Kg of the pomace; and the yield decreased by 50% in 2% saghal solian grape pomace medium. However, in 40% (W/W saghal solian semi-solid medium containing 3% methanol, the yield of citric acid production has improved to 80 g per Kg of pomace in stationary mode of production and to 120 g per Kg of pomace in the rolling mode of fermentation.

  6. improving citric acid production from some carbohydrates by-products using irradiated aspergillus niger

    International Nuclear Information System (INIS)

    Twenty strains of A. niger were isolated from different sources, screened for their capacity to produce citric acid. All the isolated strains were able to produce citric acid in different quantities at different time intervals i.e. 4, 8 and 12 days on indicator medium. The best incubation period for production for all isolates was 12 days. The most potent strains for production were A1, A4 and A5, while A8, A16, A18 and A19 recorded weak production on that medium. Citric acid productivity were obtained by all strains when using different concentrations of four carbohydrate by-products (maize straw, potato peel wastes, sugar beet pulp and molasses) when each used alone without any additions after 12 days incubation and the production enhanced when the fermentation medium amended with the same concentrations of the mentioned substrates. Type and concentration of carbohydrate by-product affect the production of citric acid by A. niger strains under the study. Increasing substrate concentration led to increase in production, the best concentration for production was 25% for all carbohydrate by-products. As recorded with indicator medium, A1, A4 and A5 are also the most potent strains for production when growing on the four carbohydrate by-products supplemented to the basal medium, while A8, A6, A18 and A19 recorded the weak production with the carbohydrate by-products used.production of the parental isolates A1, A4 and A5 on indicator medium were: 0.96, 0.95 and 0.99 (mg/ml) respectively after 12 days incubation, while maximum production by the obtaining resulting isolates (Treated by UV irradiation) were: 1.78, 1.70 and 1.73 (mg/ml) from A4T2 (5 min.), A4T1 (10 min.) and A1T1 (5 min.), respectively.

  7. Effects of Aspergillus niger inoculum concentration upon the kinetics of starchy wastewater pretreatment in a tanks-in-series bioreactor under transitory conditions

    Directory of Open Access Journals (Sweden)

    L. Coulibaly

    2007-12-01

    Full Text Available This paper discusses the effects of three Aspergillus niger inoculum concentrations (0.12, 2.3 and 3.6 g/l upon the kinetics of starch pretreatment under aerobic and transitory conditions using a tanks-in-series reactor. A synthetic wastewater containing starch as model polysaccharide was fed into the reactor system to study this polymer transformation by Aspergillus niger. Starch and metabolites (oligosaccharides with a molecular weight lower than 1 kDa in the individual reactors were quantified respectively by the starch iodine complex (SIC and anthrone methods. Enzyme activities were characterised with API ZYM kits. Starch degradation and metabolite accumulation were both influenced by both fungal inoculum and reactor HRT. Starch degradation improved from 34 to 99% with a parallel in increase inoculum concentration from 0.12 to 3.6 g/l. An overall of 400 mg/l of metabolites accumulated in the reactor system. A. niger secreted both extracellular and cell-wall-bound enzymes among which amylases.

  8. HIDROLISIS ENZIMATIK MINYAK IKAN UNTUK PRODUKSI ASAM LEMAK OMEGA-3 MENGGUNAKAN LIPASE DARI Aspergillus niger [Enzymatic Hydrolysis of Fish Oil for Production of Omega-3 Fatty Acids Using Lipase Derived from Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Sapta Raharja*

    2011-06-01

    Full Text Available Fish oil is the source of important fatty-acid, especially polyunsaturated fatty acid (PUFA omega-3, such as eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA. Lipase catalysis activity of Aspergillus niger is low when it is used in fish oil hydrolysis. The activity of the lipase can be increased by adding organic solvent such as hexane into the media. This research aimed to determine temperature, pH and amount of water which produce the highest degree of hydrolysis of fish oil in the presence of hexane. Correlation between the highest degree of hydrolysis and the amount of omega-3 fatty acid was also investigated. The variables used in this research were temperatures (25-65 oC, pH (5-9, and water addition (1-5 %v/v. The highest degree of enzymatic hydrolysis of fish oil in the media without hexane was 28.07 % that was reached at 45oC and pH 5. In the presence of hexane, the highest degree of hydrolysis was 75.12 % which was reached at 5% water addition, temperature 45oC, and pH 5. GC-MS analysis showed that omega-3 fatty acid content especially EPA and DHA increased along with increase in the degree of hydrolysis. Concentration of omega-3 fatty acid produced without hexane addition was 18.42 % with EPA amounted to 12,17% and DHA 0,86%. Meanwhile omega-3 fatty acid content in the presence of hexane reached 21.93 % with EPA amounted to 17.75 % and DHA 1.21 %.

  9. Customization of Aspergillus niger morphology through addition of talc micro particles.

    Science.gov (United States)

    Wucherpfennig, Thomas; Lakowitz, Antonia; Driouch, Habib; Krull, Rainer; Wittmann, Christoph

    2012-01-01

    The filamentous fungus A. niger is a widely used strain in a broad range of industrial processes from food to pharmaceutical industry. One of the most intriguing and often uncontrollable characteristics of this filamentous organism is its complex morphology. It ranges from dense spherical pellets to viscous mycelia. Various process parameters and ingredients are known to influence fungal morphology. Since optimal productivity correlates strongly with a specific morphological form, the fungal morphology often represents the bottleneck of productivity in industrial production. A straight forward and elegant approach to precisely control morphological shape is the addition of inorganic insoluble micro particles (like hydrous magnesium silicate, aluminum oxide or titanium silicate oxide) to the culture medium contributing to increased enzyme production. Since there is an obvious correlation between micro particle dependent morphology and enzyme production it is desirable to mathematically link productivity and morphological appearance. Therefore a quantitative precise and holistic morphological description is targeted. Thus, we present a method to generate and characterize micro particle dependent morphological structures and to correlate fungal morphology with productivity which possibly contributes to a better understanding of the morphogenesis of filamentous microorganisms. The recombinant strain A. niger SKAn1015 is cultivated for 72 h in a 3 L stirred tank bioreactor. By addition of talc micro particles in concentrations of 1 g/L, 3 g/L and 10 g/L prior to inoculation a variety of morphological structures is reproducibly generated. Sterile samples are taken after 24, 48 and 72 hours for determination of growth progress and activity of the produced enzyme. The formed product is the high-value enzyme β-fructofuranosidase, an important biocatalyst for neo-sugar formation in food or pharmaceutical industry, which catalyzes among others the reaction of sucrose to

  10. Mapping N-linked Glycosylation Sites in the Secretome and Whole Cells of Aspergillus niger Using Hydrazide Chemistry and Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lu; Aryal, Uma K.; Dai, Ziyu; Mason, Alisa C.; Monroe, Matthew E.; Tian, Zhixin; Zhou, Jianying; Su, Dian; Weitz, Karl K.; Liu, Tao; Camp, David G.; Smith, Richard D.; Baker, Scott E.; Qian, Weijun

    2012-01-01

    Protein glycosylation is known to play an essential role in both cellular functions and the secretory pathways; however, little information is available on the dynamics of glycosylated N-linked glycosites of fungi. Herein we present the first extensive mapping of glycosylated N-linked glycosites in industrial strain Aspergillus niger by applying an optimized solid phase enrichment of glycopeptide protocol using hydrazide modified magnetic beads. The enrichment protocol was initially optimized using mouse plasma and A. niger secretome samples, which was then applied to profile N-linked glycosites from both the secretome and whole cell lysates of A. niger. A total of 847 unique N-linked glycosites and 330 N-linked glycoproteins were confidently identified by LC-MS/MS. Based on gene ontology analysis, the identified N-linked glycoproteins in the whole cell lysate were primarily localized in the plasma membrane, endoplasmic reticulum, golgi apparatus, lysosome, and storage vacuoles. The identified N-linked glycoproteins are involved in a wide range of biological processes including gene regulation and signal transduction, protein folding and assembly, protein modification and carbohydrate metabolism. The extensive coverage of glycosylated N-linked glycosites along with identification of partial N-linked glycosylation in those enzymes involving in different biochemical pathways provide useful information for functional studies of N-linked glycosylation and their biotechnological applications in A. niger.

  11. Nariginase of Aspergillus niger: Production optimization by response surface methodology and utilisation of ultrasound for extraction
    Naringinase de Aspergillus niger: Otimização da produção por metodologia de superfície de resposta e uso do ultrassom para extração

    OpenAIRE

    Maria Antonia Pedrine Colabone Celligoi; João Batista Buzato; Dionizio Borsato; Cristiani Barros da Silva Rosa

    2011-01-01

    Brazil is the world's largest producer of orange and concentrated juice for export. Concentrated juice with high levels of naringin has excessive bitterness, which reduces the quality and value on the market. The debittering can be obtained by using naringinase, an enzymatic complex that degrades naringin. This study reports the production of naringinase by Aspergillus niger 426 utilizing both sugar cane molasses as carbon source and yeast extract as nitrogen source. Naringin was used as indu...

  12. Fermentation of sugar beet waste by ¤Aspergillus niger¤ facilitates growth and P uptake of external mycelium of mixed populations of arbuscular mycorrhizal fungi

    DEFF Research Database (Denmark)

    Medina, A.; Jakobsen, Iver; Vassilev, N.;

    2007-01-01

    Sugar beet waste has potential value as a soil amendment and this work studied whether fermentation of the waste by Aspergillus niger would influence the growth and P uptake of arbuscular mycorrhizal (AM) fungi. Plants were grown in compartmentalised growth units, each with a root compartment (RC......) and two lateral root-free compartments (RFC). One RFC contained untreated soil while the other RFC contained soil, which was uniformly mixed with sugar beet waste, either untreated (SB) or degraded by A. niger (ASB) in a rock phosphate (RP)-supplied medium. The soil in each pair of RFC was labelled......-positive and Gram-negative bacteria was higher in SB than in ASB treatments. Whilst ASB increased growth and activity of AM mycelium, SB had the opposite effect. Moreover, shoot P content was increased by the addition of ASB, and by inoculation with AM fungi. Modification of soil microbial structure and...

  13. Application of response surface methodology for optimization of polygalacturonase production by Aspergillus niger.

    Science.gov (United States)

    Yadav, Kaushlesh K; Garg, Neelima; Kumar, Devendra; Kumar, Sanjay; Singh, Achal; Muthukumar, M

    2015-01-01

    Polygalacturonase (PG) degrades pectin into D-galacturonic acid monomers and is used widely in food industry especially for juice clarification. In the present study,. fermentation conditions for polygalacturonase production by Asgergillus niger NAIMCCF-02958, using mango peel as substrate, were optimized using the 2(3) factorial design with central composite rotatable experimental design (CCRD) of response surface methodology (RSM). The maximum PG activity 723.66 U g(-1) was achieved under pH 4.0, temperature 30 degrees C and 2% inoculum by response surface curve. The experimental value of PG activity wkas higher 607.65 U g(-1) than the predicted value 511.75 U g(-1). Under the proposed optimized conditions, the determination coefficient (R2) was equal to 0.66 indicating that the model could explain 66% of the total variation as well as establish the relationship between the variables and the responses. ANOVA analysis and the three dimensional plots also confirmed interactions among the parameters. PMID:26536801

  14. Mixed disulfide formation at Cys141 leads to apparent unidirectional attenuation of Aspergillus niger NADP-glutamate dehydrogenase activity.

    Directory of Open Access Journals (Sweden)

    Adhish S Walvekar

    Full Text Available NADP-Glutamate dehydrogenase from Aspergillus niger (AnGDH exhibits sigmoid 2-oxoglutarate saturation. Incubation with 2-hydroxyethyl disulfide (2-HED, the disulfide of 2-mercaptoethanol resulted in preferential attenuation of AnGDH reductive amination (forward activity but with a negligible effect on oxidative deamination (reverse activity, when monitored in the described standard assay. Such a disulfide modified AnGDH displaying less than 1.0% forward reaction rate could be isolated after 2-HED treatment. This unique forward inhibited GDH form (FIGDH, resembling a hypothetical 'one-way' active enzyme, was characterized. Kinetics of 2-HED mediated inhibition and protein thiol titrations suggested that a single thiol group is modified in FIGDH. Two site-directed cysteine mutants, C141S and C415S, were constructed to identify the relevant thiol in FIGDH. The forward activity of C141S alone was insensitive to 2-HED, implicating Cys141 in FIGDH formation. It was observed that FIGDH displayed maximal reaction rate only after a pre-incubation with 2-oxoglutarate and NADPH. In addition, compared to the native enzyme, FIGDH showed a four fold increase in K0.5 for 2-oxoglutarate and a two fold increase in the Michaelis constants for ammonium and NADPH. With no change in the GDH reaction equilibrium constant, the FIGDH catalyzed rate of approach to equilibrium from reductive amination side was sluggish. Altered kinetic properties of FIGDH at least partly account for the observed apparent loss of forward activity when monitored under defined assay conditions. In sum, although Cys141 is catalytically not essential, its covalent modification provides a striking example of converting the biosynthetic AnGDH into a catabolic enzyme.

  15. Alkaline thermostable pectinase enzyme from Aspergillus niger strain MCAS2 isolated from Manaslu Conservation Area, Gorkha, Nepal.

    Science.gov (United States)

    Khatri, Bhim Prakash; Bhattarai, Tribikram; Shrestha, Sangita; Maharjan, Jyoti

    2015-01-01

    Pectinase enzymes are one of the commercially important enzymes having great potential in various industries especially in food industry. Pectinases accounts for 25 % of global food enzymes produced and their market is increasing day by day. Therefore, the exploration of microorganism with novel characteristics has always been the focus of the research. Microorganism dwelling in unique habitat may possess unique characteristics. As such, a pectinase producing fungus Aspergillus niger strain MCAS2 was isolated from soil of Manaslu Conservation Area (MCA), Gorkha, Nepal. The optimum production of pectinase enzyme was observed at 48 h of fermentation. The pectinase enzyme was partially purified by cold acetone treatment followed by Sephadex G-75 gel filtration chromatography. The partially purified enzyme exhibited maximum activity 60 U/mg which was almost 8.5-fold higher than the crude pectinase. The approximate molecular weight of the enzyme was found to be 66 kDa as observed from SDS-PAGE. The pectinase enzyme was active at broad range of temperature (30-70 °C) and pH (6.2-9.2). Optimum temperature and pH of the pectinase enzyme were 50 °C and 8.2 respectively. The enzyme was stable up to 70 °C and about 82 % of pectinase activity was still observed at 100 °C. The thermostable and alkaline nature of this pectinase can meet the demand of various industrial processes like paper and pulp industry, in textile industry, fruit juice industry, plant tissue maceration and wastewater treatment. In addition, the effect of different metal ions on pectinase activity was also studied. PMID:26380164

  16. Influence of point mutations near the active site on the catalytic properties of fungal arylacetonitrilases from Aspergillus niger and Neurospora crassa

    Czech Academy of Sciences Publication Activity Database

    Petříčková, Alena; Sosedov, O.; Baum, S.; Stolz, A.; Martínková, Ludmila

    2012-01-01

    Roč. 77, MAY 2012 (2012), s. 74-80. ISSN 1381-1177 R&D Projects: GA ČR(CZ) GAP504/11/0394; GA ČR GD305/09/H008; GA AV ČR IAA500200708; GA MŠk(CZ) LC06010; GA MŠk OC09046 Institutional research plan: CEZ:AV0Z50200510 Keywords : Arylacetonitrilase variants * Aspergillus niger * Neurospora crassa Subject RIV: CE - Biochemistry Impact factor: 2.823, year: 2012

  17. Acid protease and formation of multiple forms of glucoamylase in batch and continuous cultures of Aspergillus niger

    DEFF Research Database (Denmark)

    Aalbæk, Thomas; Reeslev, Morten; Jensen, Bo; Eriksen, Susanne Havn

    2002-01-01

    In order to identify factors responsible for production of multiple forms of glucoamylase (GA) by Aspergillus niger Bo-1, the fungus was cultured in both complex and defined media in pH-controlled batch fermenters and chemostats. At all culture conditions three forms of GA were produced with...... extracellular profile of the multiple forms of GA by degradation of GAI to GAII, whereas no proteolytic processing of the GA profile was observed in the defined medium. In vitro experiments confirmed that the pH-induced modifications of the GA multiple-form profile were caused by proteolytic and not spontaneous...

  18. The alpha-galactosidase type A gene aglA from Aspergillus niger encodes a fully functional alpha-N-acetylgalactosaminidase

    Czech Academy of Sciences Publication Activity Database

    Kulik, Natallia; Weignerová, L.; Filipi, Tomáš; Pompach, Petr; Novák, Petr; Mrázek, H.; Slámová, Kristýna; Bezouška, K.; Křen, Vladimír; Ettrich, Rüdiger

    2010-01-01

    Roč. 20, č. 11 (2010), s. 1410-1419. ISSN 0959-6658 R&D Projects: GA MŠk(CZ) LC06010; GA ČR GAP207/10/1934; GA ČR GAP207/10/1040; GA ČR GA303/09/0477; GA ČR GAP207/10/0321 Institutional research plan: CEZ:AV0Z60870520; CEZ:AV0Z50200510; CEZ:AV0Z10750506 Keywords : α-N- acetylgalactosaminidase * α-galactosidase * Aspergillus niger * substrate binding * molecular modeling Subject RIV: CE - Biochemistry Impact factor: 3.791, year: 2010

  19. Optimization of Initial pH and Total Sugar Concentration Variables on Citric Acid Production from Pineapple Waste with Aspergillus niger Yeast by Using Response Surface Methodology

    OpenAIRE

    Widayat Widayat; Abdullah Abdullah; H. Satriadi; M Hadi

    2011-01-01

    Citric acid can be produced from pineapple waste by using fermentation process. This process is done in bubble column reactor with Aspergillus niger yeast. The objective of this research is to find the optimum conditions of initial pH and total sugar concentration. The optimization method used was response surface methodology. This research was carried out at a temperature of 30 oC, spore concentration of 1.23 x 109 spore/ml, total volume 2.0 liter, flow rate of air 58.07 cc/sec and a 5% anti...

  20. The use of rock phosphate and phosphate solubilising fungi (Aspergillus niger) to improve the growth and the yield of upland rice on typic kandiudalf

    International Nuclear Information System (INIS)

    Field experiment was conducted to study the effect of rock phosphate (RP) and phosphate solubilizing fungi application on upland rice yield intercropped with pigeon pea from 2009 to 2011 at the Agricultural Research Centre, Kade, University of Ghana. In the first year, the main plot treatment consisted of five levels of phosphate fertilizer viz. 0 kg/ha P2O5, 40 kg/ha P2O5 RP, 80 kg/ha P2O5 RP, 120 kg/ha P2O5 RP and 45 kg/ha P2O5-triple super phosphate (TSP), while the planting dates of pigeon pea was set up as subplot (40 DAS –pigeon pea planted 40 days after sowing rice seed and 80 DAS- pigeon pea planted 80 days after sowing rice). In the second year, phosphate fertilizer was the main plot treatment, consisting of (0 kg/ha P2O5, 45 kg/ha P2O5 RP, 90 kg/ha P2O5 RP and 45 kg/ha P2O5 TSP), and the subplot treatment was inoculated and uninoculated with phosphate solubilising fungi Aspergillus niger. The highest grain yield of 1.051 t/ha was obtained with the 120 kg P2O5 /ha RP followed by the 40 kg P2O5 /ha RP. Phosphate levels did not significantly influence the grain yield in the first year (p = 0.08) but planting pigeon pea as an intercrop at the different planting dates had a significant positive effect on both the grain and straw yields of rice (p = 0.016, .07). There was no significant interaction between the use of different phosphorus levels and the different planting dates of pigeon pea (p = 0.348). In the second year, phosphate levels had significant influence on grain yield (p = 0.014) and the highest grain and straw yields occurred where TSP and Aspergillus niger were used to plant rice. Inoculating rice with or without Aspergillus niger had no significant influence on grain yields (p = 0.447). No significant interaction existed between phosphate levels and level of inoculation (p = 0.206). The use of TSP and Aspergillus niger to grow rice improved rice yield followed by 45 kg P2O5/ha RP + Inoculation.(au)

  1. Identification of a Classical Mutant in the Industrial Host Aspergillus niger by Systems Genetics: LaeA Is Required for Citric Acid Production and Regulates the Formation of Some Secondary Metabolites

    DEFF Research Database (Denmark)

    Niu, Jing; Arentshorst, Mark; Nair, P. Deepa S.;

    2015-01-01

    The asexual filamentous fungus Aspergillus niger is an important industrial cell factory for citric acid production. In this study, we genetically characterized a UV-generated A. niger mutant that was originally isolated as a nonacidifying mutant, which is a desirable trait for industrial enzyme...... with high-throughput genome sequencing to identify the mutation responsible for the nonacidifying phenotype. Since A. niger has no sexual cycle, parasexual genetics was used to generate haploid segregants derived from diploids by loss of whole chromosomes. We found that the nonacidifying phenotype was...

  2. Secretome analysis of Trichoderma reesei and Aspergillus niger cultivated by submerged and sequential fermentation processes: Enzyme production for sugarcane bagasse hydrolysis.

    Science.gov (United States)

    Florencio, Camila; Cunha, Fernanda M; Badino, Alberto C; Farinas, Cristiane S; Ximenes, Eduardo; Ladisch, Michael R

    2016-08-01

    Cellulases and hemicellulases from Trichoderma reesei and Aspergillus niger have been shown to be powerful enzymes for biomass conversion to sugars, but the production costs are still relatively high for commercial application. The choice of an effective microbial cultivation process employed for enzyme production is important, since it may affect titers and the profile of protein secretion. We used proteomic analysis to characterize the secretome of T. reesei and A. niger cultivated in submerged and sequential fermentation processes. The information gained was key to understand differences in hydrolysis of steam exploded sugarcane bagasse for enzyme cocktails obtained from two different cultivation processes. The sequential process for cultivating A. niger gave xylanase and β-glucosidase activities 3- and 8-fold higher, respectively, than corresponding activities from the submerged process. A greater protein diversity of critical cellulolytic and hemicellulolytic enzymes were also observed through secretome analyses. These results helped to explain the 3-fold higher yield for hydrolysis of non-washed pretreated bagasse when combined T. reesei and A. niger enzyme extracts from sequential fermentation were used in place of enzymes obtained from submerged fermentation. An enzyme loading of 0.7 FPU cellulase activity/g glucan was surprisingly effective when compared to the 5-15 times more enzyme loadings commonly reported for other cellulose hydrolysis studies. Analyses showed that more than 80% consisted of proteins other than cellulases whose role is important to the hydrolysis of a lignocellulose substrate. Our work combined proteomic analyses and enzymology studies to show that sequential and submerged cultivation methods differently influence both titers and secretion profile of key enzymes required for the hydrolysis of sugarcane bagasse. The higher diversity of feruloyl esterases, xylanases and other auxiliary hemicellulolytic enzymes observed in the enzyme

  3. Bioconversion of Agave tequilana fructans by exo-inulinases from indigenous Aspergillus niger CH-A-2010 enhances ethanol production from raw Agave tequilana juice.

    Science.gov (United States)

    Huitrón, Carlos; Pérez, Rosalba; Gutiérrez, Luís; Lappe, Patricia; Petrosyan, Pavel; Villegas, Jesús; Aguilar, Cecilia; Rocha-Zavaleta, Leticia; Blancas, Abel

    2013-01-01

    Agave tequilana fructans are the source of fermentable sugars for the production of tequila. Fructans are processed by acid hydrolysis or by cooking in ovens at high temperature. Enzymatic hydrolysis is considered an alternative for the bioconversion of fructans. We previously described the isolation of Aspergillus niger CH-A-2010, an indigenous strain that produces extracellular inulinases. Here we evaluated the potential application of A. niger CH-A-2010 inulinases for the bioconversion of A. tequilana fructans, and its impact on the production of ethanol. Inulinases were analyzed by Western blotting and thin layer chromatography. Optimal pH and temperature conditions for inulinase activity were determined. The efficiency of A. niger CH-A-2010 inulinases was compared with commercial enzymes and with acid hydrolysis. The hydrolysates obtained were subsequently fermented by Saccharomyces cerevisiae to determine the efficiency of ethanol production. Results indicate that A. niger CH-A-2010 predominantly produces an exo-inulinase activity. Optimal inulinase activity occurred at pH 5.0 and 50 °C. Hydrolysis of raw agave juice by CH-A-2010 inulinases yielded 33.5 g/l reducing sugars, compared with 27.3 g/l by Fructozyme(®) (Novozymes Corp, Bagsværd, Denmark) and 29.4 g/l by acid hydrolysis. After fermentation of hydrolysates, we observed that the conversion efficiency of sugars into ethanol was 97.5 % of the theoretical ethanol yield for enzymatically degraded agave juice, compared to 83.8 % for acid-hydrolyzed juice. These observations indicate that fructans from raw Agave tequilana juice can be efficiently hydrolyzed by using A. niger CH-A-2010 inulinases, and that this procedure impacts positively on the production of ethanol. PMID:23160922

  4. Construction of a promoter probe vector autonomously maintained in Aspergillus and characterization of promoter regions derived from A. niger and A. oryzae genomes.

    Science.gov (United States)

    Ozeki, K; Kanda, A; Hamachi, M; Nunokawa, Y

    1996-03-01

    We used a plasmid carrying a sequence for autonomous maintenance in Aspergillus (AMA1) and the E. coli uidA gene as a reporter gene to search the A. oryzae and A. niger genomes for DNA fragments having strong promoter activity. Beta-glucuronidase (GUS)-producing A. oryzae transformants containing the No. 8AN derived from A. niger, or the No. 9AO derived from A. oryzae, were constitutive for the expression of the uidA gene when cultivated in the presence of a variety of carbon and nitrogen sources. When the GUS-producing transformants were grown in liquid culture, the No. 8AN showed an increase of approximately 3-fold in GUS activity compared to the amyB (alpha-amylase encoding gene) promoter. There was also a corresponding increase in the amount of GUS gene-specific mRNA. When these transformants were grown as rice-koji, the No. 8AN showed an increase of approximately 6-fold compared to the amyB promoter, and the amount of GUS protein produced also increased. These strong promoter regions might be applicable to the production of other heterologous proteins in Aspergillus species. PMID:8901095

  5. Response surface methodology for optimization of culture conditions for dye decolorization by a fungus, Aspergillus niger HM11 isolated from dye affected soil

    Directory of Open Access Journals (Sweden)

    P Lakshmanaperumalsamy

    2010-12-01

    Full Text Available Background and Objectives: Discharge of wastewater from textile dyeing industries has been a problem in terms of pollution and treatment of these waters is a great task. Keeping this in mind, the aim of our current research is to study the effect of various bioprocess variables on decolorization of an azo dye, Congo red, by a fungal isolate, Aspergillus niger HM11."nMaterials and Methods: Central composite design (CCD and response surface methodology (RSM have been applied to design experiments to evaluate the interactive effects of the operating variables: on the decolorization of Congo red. A total of 30 experiments were conducted in the present study and a regression coefficient between the variables was generated."nResults: The RSM indicated that pH 6.0, 150 rpm agitation, incubation time of 36 hrs and a glucose concentration of 1.0% were optimal for maximum decolorization of Congo red and the response indicated excellent evaluation of experimental data."nConclusion: From this study, it is very obvious that the fungal isolate, Aspergillus niger HM11 can be used as a promising microbial strain for decolorization of textile dyeing effluent containing similar dyes.

  6. Evaluasi Nilai Nutrisi dan Kecernaan In Vitro Pelepah Kelapa Sawit (Oil Palm Fronds yang Difermentasi Menggunakan Aspergillus niger dengan Penambahan Sumber Karbohidrat yang Berbeda

    Directory of Open Access Journals (Sweden)

    Sitti Wajizah

    2015-04-01

    Full Text Available (The evaluation of  nutritive value and In Vitro digestibility of oil palm fronds through fermentation by using  Aspergillus niger  with  different soluble carbohydrate sources  ABSTRACT. Oil palm frond (OPF is one of potential sources of alternative feed, but has limited use due to high crude fiber and low crude protein contents. Fermentation is one of the methods widely applied to improve nutritive value of animal feed. The purpose of this research is to increase nutritive value of fermented oil palm fronds by adding different soluble carbohydrate source into fermentation media. The results of the experiments indicated that fermented oil palm fronds by Aspergillus niger had a significant effect (P<0,05  on the content of crude protein, crude fiber, and ash. Generally, fermented oil palm fronds with different soluble carbohydrate was able to increase the content of crude protein of oil palm fronds, but not optimal yet in reducing the crude fiber content of fermented substrate. However, the addition of rice bran on the fermentation medium showed the best results, characterized by increasing crude protein and decreasing crude fiber contents as well as improved dry matter and organic matter digestibility, reflected in high concentration of VFA.

  7. 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 ...

  8. Relation between citric acid production by solid-state fermentation from cassava bagasse and respiration of Aspergillus niger LPB 21 in semi-pilot scale

    Directory of Open Access Journals (Sweden)

    Flávera Camargo Prado

    2005-06-01

    Full Text Available The aim of this work was to study the relation between citric acid production and respiration of Aspergillus niger LPB 21 in solid-state fermentation of cassava bagasse. The experiments were carried out in horizontal drum bioreactor coupled with a gas chromatography system. Fermentation was conduced for 144 h with initial substrate moisture of 60% using heat-treated cassava bagasse as sole carbon source. The exhausted air from the bioreactor was analyzed for the monitoring of CO2 produced and O2 consumed in order to estimate the biomass biosynthesis by the fungal culture. The metabolic activity of A. niger growth was associated to citric acid production. The system using FERSOL software determined 4.372 g of biomass/g of consumed O2. Estimated and analytically determined biomass values followed the same pattern showing that the applied mathematical model was adapted.Este estudo permitiu verificar a relação ente a produção de ácido cítrico e a respiração do Aspergillus niger LPB 21 na fermentação no estado sólido do bagaço de mandioca. Os experimentos foram realizados em biorreator tipo tambor horizontal acoplado com um sistema de cromatografia gasosa. A fermentação foi conduzida durante 144 h com 60% de umidade inicial do substrato usando bagaço de mandioca termicamente tratado como única fonte de carbono. O ar de saída do biorreator foi analisado para monitorar a produção de CO2 e o consumo de O2 com o objetivo de estimar a biomassa sintetizada pelo fungo. A atividade metabólica do crescimento do Aspergillus niger está associada à produção de ácido cítrico. Usando o software FERSOL, o sistema determinou uma biomassa de 4.372 g de biomassa/g de O2 consumido. Os valores da biomassa estimada e da determinada analiticamente seguiram a mesma tendência mostrando que o modelo matemático aplicado foi adaptado.

  9. Impact of alg3 gene deletion on growth, development, pigment production, protein secretion, and functions of recombinant Trichoderma reesei cellobiohydrolases in Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Ziyu; Aryal, Uma K.; Shukla, Anil; Qian, Wei-Jun; Smith, Richard D.; Magnuson, Jon K.; Adney, William S.; Beckham, Gregg T.; Brunecky, Roman; Himmel, Michael E.; Decker, Stephen R.; Ju, Xiaohui; Zhang, Xiao; Baker, Scott E.

    2013-12-01

    ALG3 is a Family 58 glycosyltransferase enzyme involved in early N-linked glycan synthesis. Here, we investigated the effect of the alg3 gene disruption on growth, development, metabolism, and protein secretion in Aspergillus niger. The alg3 gene deletion resulted in a significant reduction of growth on complete (CM) and potato dextrose agar (PDA) media and a substantial reduction of spore production on CM. It also delayed spore germination in the liquid cultures of both CM and PDA media, but led to a significant accumulation of red pigment on both CM and liquid modified minimal medium (MM) supplemented with yeast extract. The relative abundance of 55 proteins of the total 190 proteins identified in the secretome was significantly different as a result of alg3 gene deletion. Comparison of a Trichoderma reesei cellobiohydrolase (Cel7A) heterologously expressed in A. niger parental and Δalg3 strains showed that the recombinant Cel7A expressed in the mutant background was smaller in size than that from the parental strains. This study suggests that ALG3 is critical for growth and development, pigment production, and protein secretion in A. niger. Functional analysis of recombinant Cel7A with aberrant glycosylation demonstrates the feasibility of this alternative approach to evaluate the role of N-linked glycosylation in glycoprotein secretion and function.

  10. The oxygen isotope composition of phosphate released from phytic acid by the activity of wheat and Aspergillus niger phytase

    Science.gov (United States)

    von Sperber, C.; Tamburini, F.; Brunner, B.; Bernasconi, S. M.; Frossard, E.

    2015-07-01

    Phosphorus (P) is an essential nutrient for living organisms. Under P-limiting conditions plants and microorganisms can exude extracellular phosphatases that release inorganic phosphate (Pi) from organic phosphorus compounds (Porg). Phytic acid (myo-inositol hexakisphosphate, IP6) is an important form of Porg in many soils. The enzymatic hydrolysis of IP6 by phytase yields available Pi and less phosphorylated inositol derivates as products. The hydrolysis of organic P compounds by phosphatases leaves an isotopic imprint on the oxygen isotope composition (δ18O) of released Pi, which might be used to trace P in the environment. This study aims at determining the effect of phytase on the oxygen isotope composition of released Pi. For this purpose, enzymatic assays with histidine acid phytases from wheat and Aspergillus niger were prepared using IP6, adenosine 5'-monophosphate (AMP) and glycerophosphate (GPO4) as substrates. For a comparison to the δ18O of Pi released by other extracellular enzymes, enzymatic assays with acid phosphatases from potato and wheat germ with IP6 as a substrate were prepared. During the hydrolysis of IP6 by phytase, four of the six Pi were released, and one oxygen atom from water was incorporated into each Pi. This incorporation of oxygen from water into Pi was subject to an apparent inverse isotopic fractionation (ϵ ~ 6 to 10 ‰), which was similar to that imparted by acid phosphatase from potato during the hydrolysis of IP6 (ϵ ~ 7 ‰), where less than three Pi were released. The incorporation of oxygen from water into Pi during the hydrolysis of AMP and GPO4 by phytase yielded a normal isotopic fractionation (ϵ ~ -12 ‰), similar to values reported for acid phosphatases from potato and wheat germ. We attribute this similarity in ϵ to the same amino acid sequence motif (RHGXRXP) at the active site of these enzymes, which leads to similar reaction mechanisms. We suggest that the striking

  11. The oxygen isotope composition of phosphate released from phytic acid by the activity of wheat and Aspergillus niger phytase

    Directory of Open Access Journals (Sweden)

    C. v. Sperber

    2015-03-01

    Full Text Available Phosphorus (P is an essential nutrient for living organisms. Under P-limiting conditions plants and microorganisms can exude extracellular phosphatases that release inorganic phosphate (Pi from organic phosphorus compounds (Porg. Phytic acid (IP6 is an important form of Porg in many soils. The enzymatic hydrolysis of IP6 by phytase yields plant available inorganic phosphate (Pi and less phosphorylated inositol derivates as products. The hydrolysis of organic P-compounds by phosphatases leaves an isotopic imprint on the oxygen isotope composition (δ18O of released Pi, which might be used to trace P in the environment. This study aims at determining the effect of phytase on the oxygen isotope composition of released Pi. For this purpose, enzymatic assays with histidine acid phytases from wheat and Aspergillus niger were prepared using IP6, adenosine 5'monophosphate (AMP and glycerophosphate (GPO4 as substrates. For a comparison to the δ18O of Pi released by other extracellular enzymes, enzymatic assays with acid phosphatases from potato and wheat germ with IP6 as substrate were prepared. During the hydrolysis of IP6 by phytase, four Pi are released, and one oxygen atom from water is incorporated into each Pi. This incorporation of oxygen from water into Pi is subject to an apparent inverse isotopic fractionation (ϵ ∼ 6 to 10‰, which is similar to that imparted by acid phosphatase from potato during the hydrolysis of IP6 (ϵ ∼ 7‰ where less than three Pi are released. The incorporation of oxygen from water into Pi during the hydrolysis of AMP and GPO4 by phytase yielded a normal isotopic fractionation (ϵ ∼ −12‰, again similar to values reported for acid phosphatases from potato and wheat germ. We attribute this similarity in ε to the same amino acid sequence motif (RHGXRXP at the active site of these enzymes, which leads to similar reaction mechanisms. We suggest that the striking substrate

  12. Transcriptomic and molecular genetic analysis of the cell wall salvage response of Aspergillus niger to the absence of galactofuranose synthesis.

    Science.gov (United States)

    Park, Joohae; Hulsman, Mark; Arentshorst, Mark; Breeman, Matthijs; Alazi, Ebru; Lagendijk, Ellen L; Rocha, Marina C; Malavazi, Iran; Nitsche, Benjamin M; van den Hondel, Cees A M J J; Meyer, Vera; Ram, Arthur F J

    2016-09-01

    The biosynthesis of cell surface-located galactofuranose (Galf)-containing glycostructures such as galactomannan, N-glycans and O-glycans in filamentous fungi is important to secure the integrity of the cell wall. UgmA encodes an UDP-galactopyranose mutase, which is essential for the formation of Galf. Consequently, the ΔugmA mutant lacks Galf-containing molecules. Our previous work in Aspergillus niger work suggested that loss of function of ugmA results in activation of the cell wall integrity (CWI) pathway which is characterized by increased expression of the agsA gene, encoding an α-glucan synthase. In this study, the transcriptional response of the ΔugmA mutant was further linked to the CWI pathway by showing the induced and constitutive phosphorylation of the CWI-MAP kinase in the ΔugmA mutant. To identify genes involved in cell wall remodelling in response to the absence of galactofuranose biosynthesis, a genome-wide expression analysis was performed using RNAseq. Over 400 genes were higher expressed in the ΔugmA mutant compared to the wild-type. These include genes that encode enzymes involved in chitin (gfaB, gnsA, chsA) and α-glucan synthesis (agsA), and in β-glucan remodelling (bgxA, gelF and dfgC), and also include several glycosylphosphatidylinositol (GPI)-anchored cell wall protein-encoding genes. In silico analysis of the 1-kb promoter regions of the up-regulated genes in the ΔugmA mutant indicated overrepresentation of genes with RlmA, MsnA, PacC and SteA-binding sites. The importance of these transcription factors for survival of the ΔugmA mutant was analysed by constructing the respective double mutants. The ΔugmA/ΔrlmA and ΔugmA/ΔmsnA double mutants showed strong synthetic growth defects, indicating the importance of these transcription factors to maintain cell wall integrity in the absence of Galf biosynthesis. PMID:27264789

  13. 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

  14. 含顺丁烯二酸酐结构化合物抑制黑曲霉性能的研究%Research on Inhibition of the Compound with Maleic Anhydride Structure on the Performance of Aspergillus niger

    Institute of Scientific and Technical Information of China (English)

    金侃华; 陈小龙

    2009-01-01

    [Objective]The aim was to research the relationships between the side chain of maleic anhydride structure compounds and inhibition effect on Aspergillus niger. [Method]Choosing 7 kinds of common compounds with maleic anhydride structure and tautomycin, the test of inhibiting Aspergillus niger was carried out by using oxford cup method. [Result]Diphenylmaleic anhydride with the concentration of 10 g/L had a good inhibition on Aspergillus niger, while tautomycin with the lower concentration of 1 g/L also had a considerable inhibition effect. [Conclusions]The side chain of maleic anhydride structure compounds containing chlorine could promote the inhibition effect on Aspergillus niger, and containing benzene couldn't enhance the activity of inhibition on Aspergillus niger.%[目的]研究含顺丁烯二酸酐结构化合物侧链结构与抑制黑曲霉效果的关系. [方法]选取7种常见含顺丁烯二酸酐结构化合物以及变构霉素,用牛津杯法进行抑制黑曲霉试验.[结果]3, 6-二氯邻苯二甲酸酐在10 g/L浓度下对黑曲霉有较好的抑制作用,变构霉素在1 g/L 浓度下仍对黑曲霉有一定的抑制作用. [结论]含顺丁烯二酸酐结构化合物侧链含有氯对抑制黑曲霉有促进作用,而含有苯环则不能增强其对抑制黑曲霉的活性.

  15. Degradation and Application of Aflatoxin B1 by Aspergillus Niger%黑曲霉对黄曲霉毒素B1的降解与应用研究

    Institute of Scientific and Technical Information of China (English)

    李冰; 董征英; 常维山

    2012-01-01

    试验利用黑曲霉对黄曲霉毒素B1进行了降解率、活性组分的确定、安全性及对饲料中降解黄曲霉毒素效果的研究。研究结果表明,黑曲霉对黄曲霉毒素B1的降解率达93.28%,其中黑曲霉的胞外粗提液对黄曲霉毒素B1的降解活性最高,证明黑曲霉对黄曲霉毒素B1的降解是一种生物化学反应,黑曲霉发酵液对饲料中的黄曲霉毒素B1具有很强的降解作用。小鼠的急性毒理学试验证明,试验用黑曲霉本身具有良好的安全性。%The determination of degradation efficiency and active components of aflatoxin B1 safety and the effect of degradation aflatoxin in feed about the screened aspergillus was researched in this experiment used aspergillus niger. The result showed that the degradation of aflatoxin B1 by aspergillus niger was 93.28%, the degrading efficiencies of aflatoxin B1 by exocellular coarse extraction liquid was highest, and this proved that the degration of aflatoxin B1 by aspergillus niger was a biological reaction. The degrading effect of aflatoxin B1 in feed by aspergillus fermented liquid was strong. A favorable safety of aspergillus niger was testified through the acute toxicology experiments in mice.

  16. Optimization of productions of cellulolytic enzymes by Aspergillus niger using residue of mango a substrate Otimização da produção de enzimas celulolíticas obtidas de Aspergillus niger utilizando o resíduo da manga como substrato

    OpenAIRE

    Tamires Carvalho dos Santos; Ingrid Souza Cavalcanti; Renata Cristina Ferreira Bonomo; Nivio Batista Santana; Marcelo Franco

    2011-01-01

    The present paper analyses the effects of water activity (0.88, 0.94 and 0.97) and of fermentation time (24, 48, 72, 96 and 120 hours) on the kinetic activity of enzymes cellulolytic, produced during the solid state fermentation of waste from the improvement of mango, with the aid of fungus species Aspergillus niger. Solid state fermentation was carried out at 35°C inside a bacteriological incubator. The statistical results indicated that the best activity for enzyme CMCase was 7.26U g-1 ...

  17. Aminopeptidases from Aspergillus niger

    NARCIS (Netherlands)

    Wijk, van D.

    2004-01-01

    Aspergillusis a filamentous fungus that can grow in many environments, on several substrates at different conditions. In the soil,Aspergillirecycle nutrients by the degradation of plant material. In particular,Aspergilliare known for their capabili

  18. Solid-state fermentation for gluconic acid production from sugarcane molasses by Aspergillus niger ARNU-4 employing tea waste as the novel solid support.

    Science.gov (United States)

    Sharma, Amit; Vivekanand, V; Singh, Rajesh P

    2008-06-01

    Solid-state fermentation (SSF) was evaluated to produce gluconic acid by metal resistant Aspergillus niger (ARNU-4) strain using tea waste as solid support and with molasses based fermentation medium. Various crucial parameters such as moisture content, temperature, aeration and inoculum size were derived; 70% moisture level, 30 degrees C temperature, 3% inoculum size and an aeration volume of 2.5l min(-1) was suited for maximal (76.3 gl(-1)) gluconic acid production. Non-clarified molasses based fermentation media was utilized by strain ARNU-4 and maximum gluconic acid production was observed following 8-12 days of fermentation cycle. Different concentrations of additives viz. oil cake, soya oil, jaggary, yeast extract, cheese whey and mustard oil were supplemented for further enhancement of the production ability of microorganism. Addition of yeast extract (0.5%) was observed inducive for enhanced (82.2 gl(-1)) gluconic acid production. PMID:17881224

  19. Simultaneous Cellulase Production, Saccharification and Detoxification Using Dilute Acid Hydrolysate of S. spontaneum with Trichoderma reesei NCIM 992 and Aspergillus niger.

    Science.gov (United States)

    Sateesh, Lanka; Rodhe, Adivikatla Vimala; Naseeruddin, Shaik; Yadav, Kothagauni Srilekha; Prasad, Yenumulagerard; Rao, Linga Venkateswar

    2012-06-01

    Bioethanol production from lignocellulosic materials has several limitations. One aspect is the high production cost of cellulases used for saccharification of substrate and inhibition of fermenting yeast due to inhibitors released in acid hydrolysis. In the present work we have made an attempt to achieve simultaneous cellulases production, saccharification and detoxification using dilute acid hydrolysate of Saccharum spontaneum with and without addition of nutrients, supplemented with acid hydrolyzed biomass prior to inoculation in one set and after 3 days of inoculation in another set. Organisms used were T. reesei NCIM 992, and Aspergillus niger isolated in our laboratory. Cellulase yield obtained was 0.8 IU/ml on fourth day with T. reesei. Sugars were found to increase from fourth to fifth day, when hydrolysate was supplemented with nutrients and acid hydrolyzed biomass followed by inoculation with T. reesei. Phenolics were also found to decrease by 67%. PMID:23729891

  20. Producción de ácido cítrico con Aspergillus niger NRRL 2270 a partir de suero de leche

    OpenAIRE

    CARLOS ANDRÉS LÓPEZ RÍOS; ALEJANDRO ZULUAGA MENESES; SARA NATALIA HERRERA PENAGOS; ANGELA ADRIANA RUIZ COLORADO; VICTORIA ISABEL MEDINA DE PÉREZ

    2006-01-01

    Con el fin de aprovechar el subproducto de la fabricación de queso blanco, se evaluó el suero de leche como sustrato para la producción de ácido cítrico utilizando Aspergillus niger NRRL 2270. Para este sustrato se comparó la hidrólisis ácida y enzimática de la lactosa con el fin de proporcionar al microorganismo una fuente de carbono más asimilable. En el suero entero (SE) y desproteinizado e hidrolizado (SDH), se estudió el efecto del pH y la adición de nitrógeno, además en el ...

  1. Producción de ácido cítrico con aspergillus niger nrrl 2270 a partir de suero de leche

    OpenAIRE

    López Ríos, Carlos Andrés; Zuluaga Meneses, Alejandro; Herrera Penagos, Sara Natalia; Ruiz Colorado, Angela Adriana

    2008-01-01

    Con el fin de aprovechar el subproducto de la fabricación de queso blanco, se evaluó el suero de leche como sustrato para la producción de ácido cítrico utilizando Aspergillus niger NRRL 2270. Para este sustrato se comparó la hidrólisis ácida y enzimática de la lactosa con el fin de proporcionar al microorganismo una fuente de carbono más asimilable. En el suero entero (SE) y desproteinizado e hidrolizado (SDH), se estudió el efecto del pH y la adición de nitrógeno, además en el suero hidroli...

  2. Production and Optimization of Cellulase Enzyme Using Aspergillus niger USM AI 1 and Comparison with Trichoderma reesei via Solid State Fermentation System

    OpenAIRE

    Ibrahim, C. O.; Darah, I.; Lee, C. K.

    2011-01-01

    Novel design solid state bioreactor, FERMSOSTAT, had been evaluated in cellulase production studies using local isolate Aspergillus niger USM AI 1 grown on sugarcane bagasse and palm kernel cake at 1 : 1 (w/w) ratio. Under optimised SSF conditions of 0.5 kg substrate; 70% (w/w) moisture content; 30°C; aeration at 4 L/h · g fermented substrate for 5 min and mixing at 0.5 rpm for 5 min, about 3.4 U/g of Filter paper activity (FPase) was obtained. At the same time, comparative studies of the enz...

  3. Effect of agitation speed on the morphology of Aspergillus niger HFD5A-1 hyphae and its pectinase production in submerged fermentation

    Institute of Scientific and Technical Information of China (English)

    Darah; Ibrahim; Haritharan; Weloosamy; Sheh-Hong; Lim

    2015-01-01

    AIM: To investigate the impact of agitation speed on pectinase production and morphological changing of Aspergillus niger(A. niger) HFD5A-1 in submerged fermentation. METHODS: A. niger HFM5A-1 was isolated from a rotted pomelo. The inoculum preparation was performed by adding 5.0 m L of sterile distilled water containing 0.1% Tween 80 to a sporulated culture. Cultivation was carried out with inoculated 1 × 107 spores/m L suspension and incubated at 30 ℃ with different agitation speed for 6 d. The samples were withdrawn after 6 d cultivation time and were assayed for pectinase activity and fungal growth determination. The culture broth was filtered through filter paper(Whatman No. 1, London) to separate the fungal mycelium. The cell-free culture filtrate containing the crude enzyme was then assayed for pectinase activity. The biomass was dried at 80 ℃ until constant weight. The fungal cell dry weight was then expressed as g/L. The 6 d old fungal mycelia were harvested from various agitation speed, 0, 50, 100, 150, 200 and 250 rpm. The morphological changing of samples was then viewed under the light microscope and scanning electron microscope.RESULTS: In the present study, agitation speed was found to influence pectinase production in a batch cultivation system. However, higher agitation speeds than the optimal speed(150 rpm) reduced pectinase production which due to shear forces and also collision among the suspended fungal cells in the cultivation medium. Enzyme activity increased with the increasing of agitation speed up to 150 rpm, where it achieved its maximal pectinase activity of 1.559 U/m L. There were significant different(Duncan, P < 0.05) of the pectinase production with the agitation speed at static, 50, 100, 200 and 250 rpm. At the static condition, a well growth mycelial mat was observed on the surface of the cultivation medium and sporulation occurred all over the fungal mycelial mat. However with the increased in agitation speed, the mycelial

  4. Assessing Capacity Of Aspergillus Niger And Aspergillus TERREUS For Co2+, Cd2+ And Pb2+ Uptake Using Energy Dispersive X-Ray Analysis

    International Nuclear Information System (INIS)

    The microbial removal of various cations could be useful for removal of toxic heavy metals from contaminated water. This study aims to investigate the uptake of metals in submerged culture of A. niger and A. terreus. The effect of Co2+, Cd2+ and Pb2+ on the fungal growth was studied in Czapek's Dox media. Maximum growth for A. niger and A. terreus was obtained at 0.01 and 0.01 - 0.1 mM/L, respectively. The concentration higher than 5 and 10 mM/L inhibited the growth, respectively. The results showed the ability of both fungal isolates to remove the three tested metals from the cultural media with percentage of removal 96.4, 95.5 and 99.98% at 1mM/L for the three metals respectively for A. niger, and it was 99.2% at 5 mM/L for Co2+ and 97.3 and 99.9% at 1mM/L for Cd2+ and Pb2+ for A. terreus. The EDX analysis showed that A. niger was effective than A. terreus in accumulating Cd2+ and Pb2+ while both recorded low Co2+ uptake.

  5. Influencia de la concentración de inóculo en la producción de celulasa y xilanasa por Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Myriam L. Izarra

    2010-10-01

    Full Text Available Título en inglés: Influence of inoculum concentration on the cellulase and xylanase production by Aspergillus niger Resumen Existe un gran interés por el uso de enzimas lignocelulolíticas en varias industrias, y en la biodegradación de biomasa para la producción de biocombustibles y otras aplicaciones. Entre las fuentes microbianas de enzimas, Aspergillus niger es uno de los microorganismos más utilizados en la producción de enzimas industriales, debido a sus niveles altos de secreción de proteína y a su condición GRAS (generally regarded as safe. El objetivo del presente estudio fue evaluar la influencia de la concentración de inóculo en la morfología y producción de celulasas y xilanasas con A. niger en cultivo sumergido. Para ello, fueron inoculados matraces de 250 mL con 40 mL de medio con 3% (v/v de una suspensión de 104 o 108 esporas por mililitro e incubados a 28 ºC y 175 rpm durante 120 horas. Se utilizaron 10 g*L-1 de lactosa como fuente de carbono. En cada caso se determinó la cantidad de biomasa, la proteína extracelular soluble, lactosa residual, actividad celulasa total y xilanasa cada 24 horas. Aunque no hubo un efecto notorio en la morfología de crecimiento, salvo en el color y el diámetro de pellets obtenidos, sí se afectó la µmax (0,06 y 0,03 h-1 para 104 y 108 esporas*mL-1, respectivamente y la concentración máxima de biomasa. Además, mientras que las productividades volumétricas de celulasa (ΓFPA (8,2 y 8,0 UI.*L-1*h-1 para 104 y 108 esporas*mL-1, respectivamente fueron similares para ambos inóculos, la productividad de xilanasa (ΓXIL fue mayor para el inóculo más concentrado (29,7 y 33,4 UI¨*L-1*h-1 para 104 y 108 esporas*mL-1, respectivamente. Los resultados indican que la productividad de celulasas y xilanasas está estrechamente relacionada con la concentración de inóculo. Palabras clave: celulasa; xilanasa; cultivo sumergido; morfología; Aspergillus niger. Abstract There is a great

  6. Utilization of molasses and sugar cane bagasse for production of fungal invertase in solid state fermentation using Aspergillus niger GH1.

    Science.gov (United States)

    Veana, F; Martínez-Hernández, J L; Aguilar, C N; Rodríguez-Herrera, R; Michelena, G

    2014-01-01

    Agro-industrial wastes have been used as substrate-support in solid state fermentation for enzyme production. Molasses and sugarcane bagasse are by-products of sugar industry and can be employed as substrates for invertase production. Invertase is an important enzyme for sweeteners development. In this study, a xerophilic fungus Aspergillus niger GH1 isolated of the Mexican semi-desert, previously reported as an invertase over-producer strain was used. Molasses from Mexico and Cuba were chemically analyzed (total and reducer sugars, nitrogen and phosphorous contents); the last one was selected based on chemical composition. Fermentations were performed using virgin and hydrolyzate bagasse (treatment with concentrated sulfuric acid). Results indicated that, the enzymatic yield (5231 U/L) is higher than those reported by other A. niger strains under solid state fermentation, using hydrolyzate bagasse. The acid hydrolysis promotes availability of fermentable sugars. In addition, maximum invertase activity was detected at 24 h using low substrate concentration, which may reduce production costs. This study presents an alternative method for invertase production using a xerophilic fungus isolated from Mexican semi-desert and inexpensive substrates (molasses and sugarcane bagasse). PMID:25242918

  7. Utilization of molasses and sugar cane bagasse for production of fungal invertase in solid state fermentation using Aspergillus niger GH1

    Directory of Open Access Journals (Sweden)

    F. Veana

    2014-06-01

    Full Text Available Agro-industrial wastes have been used as substrate-support in solid state fermentation for enzyme production. Molasses and sugarcane bagasse are by-products of sugar industry and can be employed as substrates for invertase production. Invertase is an important enzyme for sweeteners development. In this study, a xerophilic fungus Aspergillus niger GH1 isolated of the Mexican semi-desert, previously reported as an invertase over-producer strain was used. Molasses from Mexico and Cuba were chemically analyzed (total and reducer sugars, nitrogen and phosphorous contents; the last one was selected based on chemical composition. Fermentations were performed using virgin and hydrolyzate bagasse (treatment with concentrated sulfuric acid. Results indicated that, the enzymatic yield (5231 U/L is higher than those reported by other A. niger strains under solid state fermentation, using hydrolyzate bagasse. The acid hydrolysis promotes availability of fermentable sugars. In addition, maximum invertase activity was detected at 24 h using low substrate concentration, which may reduce production costs. This study presents an alternative method for invertase production using a xerophilic fungus isolated from Mexican semi-desert and inexpensive substrates (molasses and sugarcane bagasse.

  8. PENGARUH PERLAKUAN DELIGNIFIKASI DENGAN LARUTAN NAOH DAN KONSENTRASI SUBSTRAT JERAMI PADI TERHADAP PRODUKSI ENZIM SELULASE DARI ASPERGILLUS NIGER NRRL A-II, 264

    Directory of Open Access Journals (Sweden)

    IDA BAGUS WAYAN GUNAM

    2010-12-01

    Full Text Available his research was done in order to utilize agricultural waste (rice straw as substrate to produce crude cellulase enzyme from Aspergillus niger. This research was conducted in two stages; the first stage was determination of the initial pH and fermentation time by pH treatment (5, 6 and 7 and fermentation time (7, 9 and 11 days. The second stage was determination of concentration of NaOH treatment and concentration of substrate, namely: concentrations of NaOH (2, 4 and 6% and concentrations of substrate (1, 2 and 3% (w/v. The results showed that the fermentation time of 9 days with the initial pH 6.0 was the optimal condition for production of crude cellulase enzyme from A. niger with rice straw as a substrate. The highest enzyme activity derived from interaction of delignification treatment with NaOH concentration of 6% and 2% rice straw substrate which produces endoglukanase enzyme activity (0.037 units/ml, filter paperase activity (0.033 units/ml, soluble protein (0.362 mg/ml, and specific activity of filter paperase (0.123 units/mg.

  9. Glucose uptake and growth of glucose-limited chemostat cultures of Aspergillus niger and a disruptant lacking MstA, a high-affinity glucose transporter

    DEFF Research Database (Denmark)

    Jørgensen, Thomas R; vanKuyk, Patricia A; Poulsen, Bjarne R;

    2007-01-01

    This is a study of high-affinity glucose uptake in Aspergillus niger and the effect of disruption of a high-affinity monosaccharide-transporter gene, mstA. The substrate saturation constant (K(s)) of a reference strain was about 15 microM in glucose-limited chemostat culture. Disruption of mst......A resulted in a two- to fivefold reduction in affinity for glucose and led to expression of a low-affinity glucose transport gene, mstC, at high dilution rate. The effect of mstA disruption was more subtle at low and intermediate dilution rates, pointing to some degree of functional redundancy in the high......-affinity uptake system of A. niger. The mstA disruptant and a reference strain were cultivated in glucose-limited chemostat cultures at low, intermediate and high dilution rate (D=0.07 h(-1), 0.14 h(-1) and 0.20 h(-1)). Mycelium harvested from steady-state cultures was subjected to glucose uptake assays...

  10. Expression and biochemical characterization of recombinant α-l-rhamnosidase r-Rha1 from Aspergillus niger JMU-TS528.

    Science.gov (United States)

    Li, Lijun; Yu, Yue; Zhang, Xia; Jiang, Zedong; Zhu, Yanbing; Xiao, Anfeng; Ni, Hui; Chen, Feng

    2016-04-01

    A putative cDNA of α-l-rhamnosidase was PCR-cloned from Aspergillus niger JMU-TS528 and further extracellular over-expressed in Pichia pastoris GS115. The activity of the recombinant α-l-rhamnosidase r-Rha1 was 711.9U/mL, eightfold higher than the native α-l-rhamnosidase from A. niger JMU-TS528. r-Rha1 is a N-glycosylated protein of 90kDa and possesses broad substrate specificities by hydrolyzing α-1,2, α-1,3 α-1,4, and α-1,6 linkages to β-d-glucosides. This is the first report presenting that α-l-rhamnosidase showed activity on four kinds of glucosidic linkages. Compared with other previously characterized α-l-rhamnosidases, r-Rha1 showed a good thermostability and wide range of pH-stability with the optimum pH of 5.0 and temperature of 60°C. r-Rha1 activity was not greatly affected by representative metal ions and other detected effectors and showed excellent tolerance abilities against glucose and ethanol. These beneficial characteristics of r-Rha1 suggest that r-Rha1 should be considered a potential new biocatalyst for food and drug industrial applications. PMID:26769090

  11. Phytase production by solid-state fermentation of groundnut oil cake by Aspergillus niger: A bioprocess optimization study for animal feedstock applications.

    Science.gov (United States)

    Buddhiwant, Priyanka; Bhavsar, Kavita; Kumar, V Ravi; Khire, Jayant M

    2016-08-17

    This investigation deals with the use of agro-industrial waste, namely groundnut oil cake (GOC), for phytase production by the fungi Aspergillus niger NCIM 563. Plackett-Burman design (PBD) was used to evaluate the effect of 11 process variables and studies here showed that phytase production was significantly influenced by glucose, dextrin, distilled water, and MgSO4 · 7H2O. The use of response surface methodology (RSM) by Box-Behnken design (BBD) of experiments further enhanced the production by a remarkable 36.67-fold from the original finding of 15 IU/gds (grams of dry substrate) to 550 IU/gds. This is the highest solid-state fermentation (SSF) phytase production reported when compared to other microorganisms and in fact betters the best known by a factor of 2. Experiments carried out using dried fermented koji for phosphorus and mineral release and also thermal stability have shown the phytase to be as efficient as the liquid enzyme extract. Also, the enzyme, while exhibiting optimal activity under acidic conditions, was found to have significant activity in a broad range of pH values (1.5-6.5). The studies suggest the suitability of the koji supplemented with phytase produced in an SSF process by the "generally regarded as safe" (GRAS) microorganism A. niger as a cost-effective value-added livestock feed when compared to that obtained by submerged fermentation (SmF). PMID:26176365

  12. 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

  13. STATISTICAL OPTIMIZATION OF AQUEOUS LEAF EXTRACT OF AERVA LANATA FOR CITRININ AND FUNGAL BIOMASS REDUCTION IN SUBMERGED FERMENTATION BY ASPERGILLUS NIGER USING RESPONSE SURFACE METHODOLOGY

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    Ajaz Ahmad

    2013-12-01

    Full Text Available Citrinin, a nephrotoxic mycotoxin produced by several fungal strains belonging to the genera Penicillium, Aspergillus, and Monascus. Generally found in stored grains and after their harvest. The objective of the present investigation was to study the antimicrobial activity (anti-fungal of aqueous leaf extract of Aerva lanata and to optimize its conditions for the maximum inhibition of citrinin and fungal biomass by Aspergillus niger. Optimization of culture conditions was carried out using Box-Behnken method of response surface methodology. Extent of inhibition of citrinin was carried out using HPLC and reduction in fungal biomass was carried out using dry cell weight after comparing with controls. Optimized culture conditions as per the point prediction tool were found to be 11.27 mg/L for concentration of Aerva lanata extract, nine and half days of incubation period and temperature of 25.5 °C resulted in maximum inhibition of citrinin. These optimized values of tested parameters were and compared with control citrinin production (243.28 mg/L and dry cell weight production (362.28mg.An average of 87.77±1.21% inhibition of citrinin and 80.02±1.42% of dry cell weight was obtained in an optimized medium at 9.5th d of fermentation with 97.82 % and 96.21% validity, respectively.

  14. Isolation and NMR Characterization of Fumonisin B-2 and a New Fumonisin B-6 from Aspergillus niger

    DEFF Research Database (Denmark)

    Månsson, Maria; Klejnstrup, Marie Louise; Phipps, Richard Kerry;

    2010-01-01

    FBI and iso-FB1, having hydroxyl functions at C3, C4, and C5. Analysis of the NMR data for FB2 showed very similar chemical shift values when compared to an authentic Fusarium FB2 standard, strongly indicating identical molecules despite that an absolute stereochemical assignment of FB2 from A. niger...

  15. Expression of agsA, one of five 1,3-α-d-glucan synthase-encoding genes in Aspergillus niger, is induced in response to cell wall stress

    NARCIS (Netherlands)

    Damveld, R.A.; Kuyk, P.A. van; Arentshorst, M.; Klis, F.M.; Hondel, C.A.M.J.J. van den; Ram, A.F.J.

    2005-01-01

    1,3-α-d-Glucan is an important component of the cell wall of filamentous fungi. We have identified a family of five 1,3-α-d-glucan synthase-encoding genes in Aspergillus niger. The agsA gene was sequenced and the predicted protein sequence indicated that the overall domain structure of 1,3-α-d-gluca

  16. Gallic acid formation from gallotannins-rich agricultural wastes using Aspergillus niger AUMC 4301 or its tannase enzyme

    International Nuclear Information System (INIS)

    Gallic acid is used in many fields including dye-making, leather and chemical industries. Seven agricultural wastes were chosen for their high gallotannin content. They were apple baggages, green tea waste, mango seed kernel, olive mill, palm kernel cake, peat moss and tamarind. Each waste was used as a carbon source instead of tannic acid in the fermentation medium. Some agricultural wastes under investigation were already contain free gallic acid especially mango seed kernel followed by green tea waste, while olive mill, peat moss and tamarind were found to be free from gallic acid. The highest concentration of liberated gallic acid from wastes fermented by A. niger AUMC 4301 was occurred at the third day of fermentation. After 72 h, a sharp decrease in gallic acid accumulation was noticed. To overcome this sharp decrease, agricultural wastes were treated with extracellular crude A. niger tannase directly in stead of tannase producer. The concentration of gallic acid increased gradually and reached its maximum at 18 h incubation in case of apple baggages, green tea waste and palm kernel cake. On the other hand, gallic acid production was delayed for a lag period (12-18) h depends on the complexity of used agriculture waste. To increase the tannase productivity by A. niger AUMC 4301, the producer fungus was irradiated by different doses of γ rays, D10 value was 0.81 kGy. Radiation dose 0.5 kGy shows a positive effect on tannase productivity. An experiment examined the change in amino acid profile between irradiated and unirradiated A. niger AUMC 4301 was also conducted.

  17. The role of Coproporphyrinogen III oxidase and Ferrochelatase genes in heme biosynthesis and regulation in Aspergillus niger

    NARCIS (Netherlands)

    Punt, P.J.; Weert, S. de; Ram, A.F.J.; Hondel, C.A.M.J.J. van den; Lokman, Christien; Haas, H.; Werner, E.R.; Franken, A.C.W.

    2013-01-01

    Heme is a suggested limiting factor in peroxidase production by Aspergillus spp., which are well-known suitable hosts for heterologous protein production. In this study, the role of genes coding for coproporphyrinogen III oxidase (hemF) and ferrochelatase (hemH) was analyzed by means of deletion and

  18. The role of coproporphyrinogen III oxidase and ferrochelatase genes in heme biosynthesis and regulation in Aspergillus niger

    NARCIS (Netherlands)

    Franken, A.C.W.; Werner, E.R.; Haas, H.; Lokman, B.C.; Hondel, C.A.M.J.J. van den; Ram, A.F.J.; Weert, S. de; Punt, P.J.

    2013-01-01

    Heme is a suggested limiting factor in peroxidase production by Aspergillus spp., which are well-known suitable hosts for heterologous protein production. In this study, the role of genes coding for coproporphyrinogen III oxidase (hemF) and ferrochelatase (hemH) was analyzed by means of deletion and

  19. Expression of exo-inulinase gene from Aspergillus niger 12 in E. coli strain Rosetta-gami B (DE3) and its characterization.

    Science.gov (United States)

    Yedahalli, Shreyas S; Rehmann, Lars; Bassi, Amarjeet

    2016-05-01

    Inulin is a linear carbohydrate polymer of fructose subunits (2-60) with terminal glucose units, produced as carbon storage in selected plants. It cannot directly be taken up by most microorganisms due to its large size, unless prior hydrolysis through inulinase enzymes occurs. The hydrolyzed inulin can be taken up by microbes and/or recovered and used industrially for the production of high fructose syrup, inulo-oligosaccharides, biofuel, and nutraceuticals. Cell-free enzymatic hydrolysis would be desirable for industrial applications, hence the recombinant expression, purification and characterization of an Aspergillus niger derived exo-inulinase was investigated in this study. The eukaroyototic exo-inulinase of Aspergillus niger 12 has been expressed, for the first time, in an E. coli strain [Rosetta-gami B (DE3)]. The molecular weight of recombinant exo-inulinase was estimated to be ∼81 kDa. The values of Km and Vmax of the recombinant exo-inulinase toward inulin were 5.3 ± 1.1 mM and 402.1 ± 53.1 µmol min(-1)  mg(-1) protein, respectively. Towards sucrose the corresponding values were 12.20 ± 1.6 mM and 902.8 ± 40.2 µmol min(-1)  mg(-1) protein towards sucrose. The S/I ratio was 2.24 ± 0.7, which is in the range of native inulinase. The optimum temperature and pH of the recombinant exo-inulinase towards inulin was 55°C and 5.0, while they were 50°C and 5.5 towards sucrose. The recombinant exo-inulinase activity towards inulin was enhanced by Cu(2+) and reduced by Fe(2+) , while its activity towards sucrose was enhanced by Co(2+) and reduced by Zn(2+) . © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:629-637, 2016. PMID:26833959

  20. A modelling implementation of climate change on biodegradation of Low-Density Polyethylene (LDPE by Aspergillus niger in soil

    Directory of Open Access Journals (Sweden)

    Farzin Shabani

    2015-07-01

    Main conclusions:  Accurately evaluating the impact of landfilling on land use and predicting future climate are vital components for effective long-term planning of waste management. From a social and economic perspective, utilization of our mapped projections to detect suitable regions for establishing landfills in areas highly sustainable for microorganisms like A. niger growth will allow a significant cost reduction and improve the performance of biodegradation of LDPE over a long period of time, through making use of natural climatic and environmental factors.

  1. Production and action pattern of inulinase from Aspergillus Niger-245: hydrolysis of inulin from several sources Produção e mecanismo de ação de inulinase de Aspergillus niger-245: hidrólise de inulinas de diferentes origens

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    Vinícius D’Arcadia Cruz

    1998-10-01

    Full Text Available A strain of Aspergillus niger isolated from soil samples showed great capacity to produce extracellular inulinase. Although the enzyme has been synthesized in presence of monosaccharides, sucrose and sugar cane molasse, the productivity was significantly higher (pUma linhagem de Aspergillus niger isolada de amostras de solo mostrou grande capacidade de produzir inulinase extracelular. Embora a enzima tenha sido sintetizada na presença de monossacarídeos, sacarose e melaço de cana, a produtividade foi significativamente maior (p<0.01 quando o microrganismo foi inoculado em meios formulados com extrato de dália e inulina pura, como fontes de carbono. Em relação à fonte de nitrogênio, os melhores resultados foram obtidos com caseína e outras fontes de nitrogênio proteico, comparativamente ao nitrogênio mineral. Entretanto, somente foi encontrada significância (p<0.01 entre a produtividade obtida nos meios preparados com caseína e sulfato de amônia. O pH ótimo da enzima purificada foi localizado entre 4.0 e 4.5 e a temperatura ótima a 60ºC. Quando tratada por 30 minutos nesta temperatura nenhuma perda de atividade foi observada. A enzima mostrou capacidade de hidrolisar sacarose, rafinose e inulina, da qual liberou apenas unidades de frutose, mostrando, portanto, um mecanismo de exo-ação. Atuando sobre inulinas de diversas fontes, a enzima mostrou maior velocidade de hidrólise sobre o polissacarídeo da chicória, comparativamente, às inulinas de raízes de dalia e alcachofra.

  2. Efeito da toxicidade de Cr (VI) e Zn (II) no crescimento do fungo filamentoso Aspergillus niger isolado de efluente industrial Toxicity effect of Cr (VI) and Zn (II) on growth of filamentous fungi Aspergillus niger isolated from industrial effluent

    OpenAIRE

    Maria do Socorro Vale; Katiany do Vale Abreu; Sandro Thomaz Gouveia; Renato Carrhá Leitão; Sandra Tédde Santaella

    2011-01-01

    Processos convencionais de tratamento de efluentes utilizam microrganismos vivos, o que sugere limitações relativas À toxicidade de metais para os microrganismos. O experimento consistiu em adicionar soluções monoelementares de Cr (VI) e Zn(II) em diferentes concentrações (0, 20, 50, 100, 200, 300, 400, 500 mg.L-1) ao meio de crescimento e observar a influência dos metais no crescimento micelial e germinativo do fungo Aspergillus Níger por verificação visual da expansão radial do micélio e da...

  3. Producción de ácido cítrico con Aspergillus niger NRRL 2270 a partir de suero de leche

    Directory of Open Access Journals (Sweden)

    CARLOS ANDRÉS LÓPEZ RÍOS

    2006-01-01

    Full Text Available Con el fin de aprovechar el subproducto de la fabricación de queso blanco, se evaluó el suero de leche como sustrato para la producción de ácido cítrico utilizando Aspergillus niger NRRL 2270. Para este sustrato se comparó la hidrólisis ácida y enzimática de la lactosa con el fin de proporcionar al microorganismo una fuente de carbono más asimilable. En el suero entero (SE y desproteinizado e hidrolizado (SDH, se estudió el efecto del pH y la adición de nitrógeno, además en el suero hidrolizado (SH la complementación con sacarosa; posteriormente se estudió la adición de nitrógeno y fósforo en el SE y SDH; se determinó la producción de ácido cítrico al agregar magnesio, carboximetil celulosa (CMC, gelatina y metanol al SE. El proceso fermentativo se realizó en cultivo sumergido discontinuo agitado y a las mejores condiciones nutricionales se hizo un seguimiento de las variables del proceso en el tiempo.

  4. [Determination of the antimicrobial capacity of green tea (Camellia sinensis) against the potentially pathogenic microorganisms Escherichia coli, Salmonella enterica, Staphylococcus aureus, Listeria monocytogenes, Candida albicans and Aspergillus niger].

    Science.gov (United States)

    Mora, Andreína; Pawa, Jonathan; Chaverri, José M; Arias, María Laura

    2013-09-01

    Many studies can be found in scientific literature demonstrating the antimicrobial capacity of different herbs, including green tea. Never-theless, many results are divergent or cannot be compared. Several green tea formulations may be found in market, but there is scarce or non-information about its activity. In this work, the potential antimicrobial effect of 50 samples of dry green tea and in 10% infusion against Escherichia coli, Salmonella enterica, Listeria monocytogenes, Staphylococcus aureus, Candida albicans and Aspergillus niger distributed in the metropolitan area of Costa Rica, was determined. This activity was compared with the effect produced by Chinese origin green tea (Camellia sinensis). Different solvents were evaluated for preparing polyphenol enriched extracts from green tea samples. Total phenols were determined using the Folin-Ciocalteu spectrophotometric methodology, using galic acid as reference. Antimicrobial activity of green tea extracts and infusions was evaluated using the microplate methodology described by Breuking (2006). Ethanol was the most efficient solvent used for the polyphenol extractions. There was no antimicrobial effect of the different green tea extracts and infusions against the microorganisms evaluated, except for Listeria monocytogenes, where the extracts of 70% of samples analyzed and the control showed an inhibitory effect in the 10.5 mg/mL and 1.05 mg/L concentrations. None of the infusions tested, including the control, showed any effect against this bacteria. PMID:25362825

  5. SYNONYMOUS CONDON USAGE BIAS AND OVEREXPRESSION OF A SYNTHETIC xynB GENE FROM Aspergillus niger NL-1 IN Pichia pastoris

    Directory of Open Access Journals (Sweden)

    Fei Li, Shiyi Yang,

    2012-02-01

    Full Text Available To further improve the expression level of recombinant xylanase in Pichia pastoris, the xynB gene, encoding the mature peptide from Aspergillus niger NL-1, was designed and synthesized based on the synonymous condon bias of P. pastoris and optimized G+C content. 155 nucleotides were changed, and the GC content decreased from 57.7% to 43.6%. The synthetic xynB was inserted into the pPICZaA and then integrated into P. pastoris GS115. The activity of the recombinant xylanase reached 1414.7 U/mL, induced with 0.8% methanol after 14-day cultivation at a temperature of 28oC in shake flasks, which was 267% higher than that of the native gene. Furthermore, the maximum xylanase activity of 20424.2 U/mL was obtained by high-density fermentation in a 5-L fermenter, which was the highest xylanase expression in P. pastoris yet reported. The recombinant xylanase had its optimal activity at a pH of 5.0 and temperature of 50oC. The recombinant xylanase was stable over a pH range of 4.5 to 8.0. Thus, this report provides an industrial means to produce the recombinant xylanase in P. pastoris.

  6. Effect of C/N Ratio and Media Optimization through Response Surface Methodology on Simultaneous Productions of Intra- and Extracellular Inulinase and Invertase from Aspergillus niger ATCC 20611

    Directory of Open Access Journals (Sweden)

    Mojdeh Dinarvand

    2013-01-01

    Full Text Available The study is to identify the extraction of intracellular inulinase (exo- and endoinulinase and invertase as well as optimization medium composition for maximum productions of intra- and extracellular enzymes from Aspergillus niger ATCC 20611. From two different methods for extraction of intracellular enzymes, ultrasonic method was found more effective. Response surface methodology (RSM with a five-variable and three-level central composite design (CCD was employed to optimize the medium composition. The effect of five main reaction parameters including sucrose, yeast extract, NaNO3, Zn+2, and Triton X-100 on the production of enzymes was analyzed. A modified quadratic model was fitted to the data with a coefficient of determination (R2 more than 0.90 for all responses. The intra-extracellular inulinase and invertase productions increased in the range from 16 to 8.4 times in the optimized medium (10% (w/v sucrose, 2.5% (w/v yeast extract, 2% (w/v NaNO3, 1.5 mM (v/v Zn+2, and 1% (v/v Triton X-100 by RSM and from around 1.2 to 1.3 times greater than in the medium optimized by one-factor-at-a-time, respectively. The results of bioprocesses optimization can be useful in the scale-up fermentation and food industry.

  7. Citric acid fermentation by Aspergillus niger: Induction of high yielding mutants with the help of radiation, combination treatments, protoplast fusion and genetic engineering

    International Nuclear Information System (INIS)

    Conidia of the citric acid fermenting fungal mutant Aspergillus niger 14/20 was subjected to the gamma radiation treatment. Mutants giving higher total titrable acid values than their parent strain were selected and tested under varied environmental and cultural conditions. After screening of about 2000 mutants, two of them with the highest yield of citric acid in molasses medium (62-76 mg/ml) were selected for further experiments. Further step-wise improvements of these strains are feasible, and radiation is a potential mutagen for the selection of better strains of microorganisms for the industrial use. The cassava starch has been found to be a fairly good substract for citric acid fermentation under the solid state condition and also when mixed with molasses in surface culture condition. Agro-industrial residues such as bagasse, rice straw and saw-dust could be used as a support for the fermentation of sugars to citric acid under the solid state conditions. The use of mixed culture method (amylolytic + citric acid fermenting organisms) had not been found to improve the citric acid fermentation from cassava as a basic substrate. (author). 2 refs

  8. Characterization of β-Glucosidase Produced by Aspergillus niger under Solid-State Fermentation and Partially Purified Using MANAE-Agarose

    Directory of Open Access Journals (Sweden)

    Anderson Baraldo Junior

    2014-01-01

    Full Text Available β-Glucosidase (BGL is a hydrolytic enzyme with specificity for a wide variety of glycoside substrates, being an enzyme with a large range of biotechnological applications. However, enzyme properties can be different depending both on the microorganism and the cultivation procedure employed. Therefore, in order to explore potential biocatalytical applications of novel enzymes, their characterization is essential. In this work, a BGL synthesized by a selected strain of Aspergillus niger cultivated under solid-state fermentation (SSF was partially purified and fully characterized in terms of optimum pH, temperature, and thermostability. The single-step purification using MANAE-agarose in a chromatographic column yielded an enzyme solution with specific activity (17.1 IU/mg protein adequate for the characterization procedures. Electrophoresis SDS-PAGE and size-exclusion chromatography analysis resulted in an estimated molecular mass of 60 kDa. Higher enzyme activities were found in the range between 40 and 65°C and between pH 4 and 5.5, indicating an interesting characteristic for application in the hydrolysis of lignocellulosic biomass for biofuels production. Thermostability studies of purified BGL resulted in half-lives at 37°C of 56.3 h and at 50°C of 5.4 h. These results provide support for further studies of this enzyme towards revealing its potential biotechnological applications.

  9. Catalysis of Rice Straw Hydrolysis by the Combination of Immobilized Cellulase from Aspergillus niger on β-Cyclodextrin-Fe3O4 Nanoparticles and Ionic Liquid

    Directory of Open Access Journals (Sweden)

    Po-Jung Huang

    2015-01-01

    Full Text Available Cellulase from Aspergillus niger was immobilized onto β-cyclodextrin-conjugated magnetic particles by silanization and reductive amidation. The immobilized cellulase gained supermagnetism due to the magnetic nanoparticles. Ninety percent of cellulase was immobilized, but the activity of immobilized cellulase decreased by 10%. In this study, ionic liquid (1-butyl-3-methylimidazolium chloride was introduced into the hydrolytic process because the original reaction was a solid-solid reaction. The activity of immobilized cellulase was improved from 54.87 to 59.11 U g immobilized cellulase−1 at an ionic liquid concentration of 200 mM. Using immobilized cellulase and ionic liquid in the hydrolysis of rice straw, the initial reaction rate was increased from 1.629 to 2.739 g h−1 L−1. One of the advantages of immobilized cellulase is high reusability—it was usable for a total of 16 times in this study. Compared with free cellulase, magnetized cellulase can be recycled by magnetic field and the activity of immobilized cellulase was shown to remain at 85% of free cellulase without denaturation under a high concentration of glucose (15 g L−1. Therefore, immobilized cellulase can hydrolyze rice straw continuously compared with free cellulase. The amount of harvested glucose can be up to twentyfold higher than that from the hydrolysis by free cellulase.

  10. Optimization of Initial pH and Total Sugar Concentration Variables on Citric Acid Production from Pineapple Waste with Aspergillus niger Yeast by Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Widayat Widayat

    2011-06-01

    Full Text Available Citric acid can be produced from pineapple waste by using fermentation process. This process is done in bubble column reactor with Aspergillus niger yeast. The objective of this research is to find the optimum conditions of initial pH and total sugar concentration. The optimization method used was response surface methodology. This research was carried out at a temperature of 30 oC, spore concentration of 1.23 x 109 spore/ml, total volume 2.0 liter, flow rate of air 58.07 cc/sec and a 5% antifoam concentration. The fermentation process lasted 7 days and the citric acid concentration was analyzed by High Pressure Liquid Cromatography (HPLC method. Statistica 6 software was used for the data treatment. The mathematical model for the optimization citric acid fermentation in bubble column reactor is Y = 54.507 + 2.9851X - 8.987X12 - 2.581X2 - 15.446X22 - 7.989X1X2 The parameter of Y is citric acid yield, X1 is a coding initial pH and X2 is a coding total sugar concentration. The results has given an initial pH optimum 3.61 and total sugar concentration 19,285% w/v with optimum an yield of 55.03 % . Keywords: Bubble column bioreactor, Citric acid fermentation, Initial pH, Total sugar concentration, Response surface methodology

  11. 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...

  12. Physiology of Aspergillus niger in Oxygen-Limited Continuous Cultures: Influence of Aeration, Carbon Source Concentration and Dilution Rate

    DEFF Research Database (Denmark)

    Diano, Audrey; Peeters, J.; Dynesen, Jens Østergaard;

    2009-01-01

    of low oxygen availability, at different carbon source concentrations and at different specific growth rates, on the metabolism of A. niger, using continuous cultures. The results show that there is an increase in the production of tricarboxylic acid (TCA) cycle intermediates at low oxygen concentrations....... Indeed, at these conditions, a decrease in the mitochondrial respiratory chain activity leads to an accumulation of NADH and to a decreased ATP production which uncouples catabolism and anabolism, influences the intracellular pH and leads to production and excretion of organic acids. Moreover, mannitol...... is being produced in order to ensure reoxidation of NADH, and this is the main cellular response to balance the ratio NADH/NAD at low oxygen availability. Mannitol production is also coupled to low specific growth rate, which suggests a control of carbon catabolite repression on the mannitol pathway...

  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. The transcriptional repressor TupA in Aspergillus niger is involved in controlling gene expression related to cell wall biosynthesis, development, and nitrogen source availability.

    Directory of Open Access Journals (Sweden)

    Doreen Schachtschabel

    Full Text Available The Tup1-Cyc8 (Ssn6 complex is a well characterized and conserved general transcriptional repressor complex in eukaryotic cells. Here, we report the identification of the Tup1 (TupA homolog in the filamentous fungus Aspergillus niger in a genetic screen for mutants with a constitutive expression of the agsA gene. The agsA gene encodes a putative alpha-glucan synthase, which is induced in response to cell wall stress in A. niger. Apart from the constitutive expression of agsA, the selected mutant was also found to produce an unknown pigment at high temperatures. Complementation analysis with a genomic library showed that the tupA gene could complement the phenotypes of the mutant. Screening of a collection of 240 mutants with constitutive expression of agsA identified sixteen additional pigment-secreting mutants, which were all mutated in the tupA gene. The phenotypes of the tupA mutants were very similar to the phenotypes of a tupA deletion strain. Further analysis of the tupA-17 mutant and the ΔtupA mutant revealed that TupA is also required for normal growth and morphogenesis. The production of the pigment at 37°C is nitrogen source-dependent and repressed by ammonium. Genome-wide expression analysis of the tupA mutant during exponential growth revealed derepression of a large group of diverse genes, including genes related to development and cell wall biosynthesis, and also protease-encoding genes that are normally repressed by ammonium. Comparison of the transcriptome of up-regulated genes in the tupA mutant showed limited overlap with the transcriptome of caspofungin-induced cell wall stress-related genes, suggesting that TupA is not a general suppressor of cell wall stress-induced genes. We propose that TupA is an important repressor of genes related to development and nitrogen metabolism.

  15. Systems approaches to predict the functions of glycoside hydrolases during the life cycle of Aspergillus niger using developmental mutants ∆brlA and ∆flbA.

    Directory of Open Access Journals (Sweden)

    Jolanda M van Munster

    Full Text Available BACKGROUND: The filamentous fungus Aspergillus niger encounters carbon starvation in nature as well as during industrial fermentations. In response, regulatory networks initiate and control autolysis and sporulation. Carbohydrate-active enzymes play an important role in these processes, for example by modifying cell walls during spore cell wall biogenesis or in cell wall degradation connected to autolysis. RESULTS: In this study, we used developmental mutants (ΔflbA and ΔbrlA which are characterized by an aconidial phenotype when grown on a plate, but also in bioreactor-controlled submerged cultivations during carbon starvation. By comparing the transcriptomes, proteomes, enzyme activities and the fungal cell wall compositions of a wild type A. niger strain and these developmental mutants during carbon starvation, a global overview of the function of carbohydrate-active enzymes is provided. Seven genes encoding carbohydrate-active enzymes, including cfcA, were expressed during starvation in all strains; they may encode enzymes involved in cell wall recycling. Genes expressed in the wild-type during starvation, but not in the developmental mutants are likely involved in conidiogenesis. Eighteen of such genes were identified, including characterized sporulation-specific chitinases and An15g02350, member of the recently identified carbohydrate-active enzyme family AA11. Eight of the eighteen genes were also expressed, independent of FlbA or BrlA, in vegetative mycelium, indicating that they also have a role during vegetative growth. The ΔflbA strain had a reduced specific growth rate, an increased chitin content of the cell wall and specific expression of genes that are induced in response to cell wall stress, indicating that integrity of the cell wall of strain ΔflbA is reduced. CONCLUSION: The combination of the developmental mutants ΔflbA and ΔbrlA resulted in the identification of enzymes involved in cell wall recycling and sporulation

  16. Impact of alg3 gene deletion on growth, development, pigment production, protein secretion, and functions of recombinant Trichoderma reesei cellobiohydrolases in Aspergillus niger.

    Science.gov (United States)

    Dai, Ziyu; Aryal, Uma K; Shukla, Anil; Qian, Wei-Jun; Smith, Richard D; Magnuson, Jon K; Adney, William S; Beckham, Gregg T; Brunecky, Roman; Himmel, Michael E; Decker, Stephen R; Ju, Xiaohui; Zhang, Xiao; Baker, Scott E

    2013-12-01

    Dolichyl-P-Man:Man(5)GlcNAc(2)-PP-dolichyl α-1,3-mannosyltransferase (also known as "asparagine-linked glycosylation 3", or ALG3) is involved in early N-linked glycan synthesis and thus is essential for formation of N-linked protein glycosylation. In this study, we examined the effects of alg3 gene deletion (alg3Δ) on growth, development, pigment production, protein secretion and recombinant Trichoderma reesei cellobiohydrolase (rCel7A) expressed in Aspergillus niger. The alg3Δ delayed spore germination in liquid cultures of complete medium (CM), potato dextrose (PD), minimal medium (MM) and CM with addition of cAMP (CM+cAMP), and resulted in significant reduction of hyphal growth on CM, potato dextrose agar (PDA), and CM+cAMP and spore production on CM. The alg3Δ also led to a significant accumulation of red pigment on both liquid and solid CM cultures. The relative abundances of 54 of the total 215 proteins identified in the secretome were significantly altered as a result of alg3Δ, 63% of which were secreted at higher levels in alg3Δ strain than the parent. The rCel7A expressed in the alg3Δ mutant was smaller in size than that expressed in both wild-type and parental strains, but still larger than T. reesei Cel7A. The circular dichroism (CD)-melt scans indicated that change in glycosylation of rCel7A does not appear to impact the secondary structure or folding. Enzyme assays of Cel7A and rCel7A on nanocrystalline cellulose and bleached kraft pulp demonstrated that the rCel7As have improved activities on hydrolyzing the nanocrystalline cellulose. Overall, the results suggest that alg3 is critical for growth, sporulation, pigment production, and protein secretion in A. niger, and demonstrate the feasibility of this alternative approach to evaluate the roles of N-linked glycosylation in glycoprotein secretion and function. PMID:24076077

  17. 黑曲霉降酸菌株F1降解酒石酸关键酶的分离纯化%Isolation and Purification of Key Tartaric Acid Degrading Enzyme from Aspergillus niger F1

    Institute of Scientific and Technical Information of China (English)

    王贵珍; 董昕; 文连奎

    2012-01-01

    The purpose of this study was to prepare a key tartaric acid degrading enzyme from Aspergillus niger F1.Aspergillus niger F1 was cultured and the expression of tartaric acid degrading enzymes was induced by adding tartaric acid into the medium.Cultured mycelia of Aspergillus niger F1 were collected and homogenized in liquid nitrogen.Crude enzyme extract was obtained by ultrasonic assisted extraction,added with protamine sulfate for removing nucleic acids,denatured for removing unwanted proteins,concentrated by PEG treatment,dialyzed for desalting,and then purified by DEAE-cellulose 52 anion exchange chromatography and Sephadex G-75 gel filtration chromatography to obtain a single component with a purification factor of 14.32.The enzyme was proven to be a dehydrogenase.%为得到黑曲霉菌株F1中具有降酸作用的蛋白,将黑曲霉菌株F1经酒石酸诱导发酵得到菌丝体,用液氮研磨破碎细胞壁,超声波辅助提取得到粗酶液,硫酸鱼精蛋白去除核酸,热变除杂蛋白,聚乙二醇浓缩,透析脱盐,DEAE-纤维素52阴离子交换层析,Sephadex G-75葡聚糖凝胶柱分子筛层析,最终得到该蛋白的单一组分,其纯化倍数为14.32,并确定该酶为脱氢酶类。

  18. 产葡萄糖氧化酶黑曲霉紫外诱变及产酶条件的研究%Research on UV Mutation of Aspergillus niger and Glucose Oxidase-producing Conditions

    Institute of Scientific and Technical Information of China (English)

    朱洪菊; 袁建国; 高艳华; 李峰

    2012-01-01

    Objective To improve the production of glucose oxidase from Aspergillus niger. Methods The dominant bacterial strain was selected through UV mutation, and the conditions were optimized, including carbon source, nitrogen source, calcium carbonate, fermentation time and so on. Results The enzyme activity of Aspergillus niger fermentation liquid was 6.5 U/ml, which was five times higher than initial bacterial strain. The single factor test dedicated that the optimal carbon source was sucrose, nitrogen source was peptone and sodium nitrate, the pH of liquid medium was about 6.0, and the fermentation cycle was 48h at 30℃. Conclusion The vitality of glucose oxidase can be obviously improved through UV mutation of Aspergillus niger.%目的 提高黑曲霉中葡萄糖氧化酶的产量.方法 紫外诱变法选出产酶优势菌株,优化碳源、氮源、碳酸钙、发酵时间等条件.结果 黑曲霉发酵液酶活达到6.5 U/mL,比初始酶活提高5倍;单因素条件试验表明,最适碳源是蔗糖,最适氮源是蛋白胨和NaNO3,发酵周期为48 h,培养温度是30℃,液体培养基的初始pH值为6.0产酶效果最好.结论 紫外诱变后,葡萄糖氧化酶的活力有明显提高.

  19. Optimization of Aspergillus niger rock phosphate solubilization in solid-state fermentation and use of the resulting product as a P fertilizer.

    Science.gov (United States)

    Mendes, Gilberto de Oliveira; da Silva, Nina Morena Rêgo Muniz; Anastácio, Thalita Cardoso; Vassilev, Nikolay Bojkov; Ribeiro, José Ivo; da Silva, Ivo Ribeiro; Costa, Maurício Dutra

    2015-11-01

    A biotechnological strategy for the production of an alternative P fertilizer is described in this work. The fertilizer was produced through rock phosphate (RP) solubilization by Aspergillus niger in a solid-state fermentation (SSF) with sugarcane bagasse as substrate. SSF conditions were optimized by the surface response methodology after an initial screening of factors with significant effect on RP solubilization. The optimized levels of the factors were 865 mg of biochar, 250 mg of RP, 270 mg of sucrose and 6.2 ml of water per gram of bagasse. At this optimal setting, 8.6 mg of water-soluble P per gram of bagasse was achieved, representing an increase of 2.4 times over the non-optimized condition. The optimized SSF product was partially incinerated at 350°C (SB-350) and 500°C (SB-500) to reduce its volume and, consequently, increase P concentration. The post-processed formulations of the SSF product were evaluated in a soil-plant experiment. The formulations SB-350 and SB-500 increased the growth and P uptake of common bean plants (Phaseolus vulgaris L.) when compared with the non-treated RP. Furthermore, these two formulations had a yield relative to triple superphosphate of 60% (on a dry mass basis). Besides increasing P concentration, incineration improved the SSF product performance probably by decreasing microbial immobilization of nutrients during the decomposition of the remaining SSF substrate. The process proposed is a promising alternative for the management of P fertilization since it enables the utilization of low-solubility RPs and relies on the use of inexpensive materials. PMID:26112323

  20. Phosphate solubilization and promotion of maize growth by Penicillium oxalicum P4 and Aspergillus niger P85 in a calcareous soil.

    Science.gov (United States)

    Yin, Zhongwei; Shi, Fachao; Jiang, Hongmei; Roberts, Daniel P; Chen, Sanfeng; Fan, Bingquan

    2015-12-01

    Alternative tactics for improving phosphorus nutrition in crop production are needed in China and elsewhere, as the overapplication of phosphatic fertilizers can adversely impact agricultural sustainability. Penicillium oxalicum P4 and Aspergillus niger P85 were isolated from a calcareous soil in China that had been exposed to excessive application of phosphatic fertilizer for decades. Each isolate excreted a number of organic acids into, acidified, and solubilized phosphorus in a synthetic broth containing insoluble tricalcium phosphate or rock phosphate. Isolate P4, applied as a seed treatment, increased maize fresh mass per plant when rock phosphate was added to the calcareous soil in greenhouse pot studies. Isolate P85 did not increase maize fresh mass per plant but did significantly increase total phosphorus per plant when rock phosphate was added. Significant increases in 7 and 4 organic acids were detected in soil in association with isolates P4 and P85, respectively, relative to the soil-only control. The quantity and (or) number of organic acids produced by these isolates increased when rock phosphate was added to the soil. Both isolates also significantly increased available phosphorus in soil in the presence of added rock phosphate and effectively colonized the maize rhizosphere. Studies reported here indicate that isolate P4 is adapted to and capable of promoting maize growth in a calcareous soil. Plant-growth promotion by this isolate is likely due, at least in part, to increased phosphorus availability resulting from the excretion of organic acids into, and the resulting acidification of, this soil. PMID:26469739

  1. Optimization of ethanol, citric acid, and α-amylase production from date wastes by strains of Saccharomyces cerevisiae, Aspergillus niger, and Candida guilliermondii.

    Science.gov (United States)

    Acourene, S; Ammouche, A

    2012-05-01

    The present study deals with submerged ethanol, citric acid, and α-amylase fermentation by Saccharomyces cerevisiae SDB, Aspergillus niger ANSS-B5, and Candida guilliermondii CGL-A10, using date wastes as the basal fermentation medium. The physical and chemical parameters influencing the production of these metabolites were optimized. As for the ethanol production, the optimum yield obtained was 136.00 ± 0.66 g/l under optimum conditions of an incubation period of 72 h, inoculum content of 4% (w/v), sugars concentration of 180.0 g/l, and ammonium phosphate concentration of 1.0 g/l. Concerning citric acid production, the cumulative effect of temperature (30°C), sugars concentration of 150.0 g/l, methanol concentration of 3.0%, initial pH of 3.5, ammonium nitrate concentration of 2.5 g/l, and potassium phosphate concentration of 2.5 g/l during the fermentation process of date wastes syrup did increase the citric acid production to 98.42 ± 1.41 g/l. For the production of α-amylase, the obtained result shows that the presence of starch strongly induces the production of α-amylase with a maximum at 5.0 g/l. Among the various nitrogen sources tested, urea at 5.0 g/l gave the maximum biomass and α-amylase estimated at 5.76 ± 0.56 g/l and 2,304.19 ± 31.08 μmol/l/min, respectively after 72 h incubation at 30°C, with an initial pH of 6.0 and potassium phosphate concentration of 6.0 g/l. PMID:22193823

  2. Cloning, expression in Pichia pastoris, and characterization of a thermostable GH5 mannan endo-1,4-β-mannosidase from Aspergillus niger BK01

    Directory of Open Access Journals (Sweden)

    Sigoillot Jean-Claude

    2009-11-01

    Full Text Available Abstract Background Mannans are key components of lignocellulose present in the hemicellulosic fraction of plant primary cell walls. Mannan endo-1,4-β-mannosidases (1,4-β-D-mannanases catalyze the random hydrolysis of β-1,4-mannosidic linkages in the main chain of β-mannans. Biodegradation of β-mannans by the action of thermostable mannan endo-1,4-β-mannosidase offers significant technical advantages in biotechnological industrial applications, i.e. delignification of kraft pulps or the pretreatment of lignocellulosic biomass rich in mannan for the production of second generation biofuels, as well as for applications in oil and gas well stimulation, extraction of vegetable oils and coffee beans, and the production of value-added products such as prebiotic manno-oligosaccharides (MOS. Results A gene encoding mannan endo-1,4-β-mannosidase or 1,4-β-D-mannan mannanohydrolase (E.C. 3.2.1.78, commonly termed β-mannanase, from Aspergillus niger BK01, which belongs to glycosyl hydrolase family 5 (GH5, was cloned and successfully expressed heterologously (up to 243 μg of active recombinant protein per mL in Pichia pastoris. The enzyme was secreted by P. pastoris and could be collected from the culture supernatant. The purified enzyme appeared glycosylated as a single band on SDS-PAGE with a molecular mass of approximately 53 kDa. The recombinant β-mannanase is highly thermostable with a half-life time of approximately 56 h at 70°C and pH 4.0. The optimal temperature (10-min assay and pH value for activity are 80°C and pH 4.5, respectively. The enzyme is not only active towards structurally different mannans but also exhibits low activity towards birchwood xylan. Apparent Km values of the enzyme for konjac glucomannan (low viscosity, locust bean gum galactomannan, carob galactomannan (low viscosity, and 1,4-β-D-mannan (from carob are 0.6 mg mL-1, 2.0 mg mL-1, 2.2 mg mL-1 and 1.5 mg mL-1, respectively, while the kcat values for these

  3. 肉桂、紫苏精油对青霉和黑曲霉抑菌特性研究%Study on Antifungal Properties of Cinnamon and Perilla oil on Penicillium sp. and Aspergillus niger

    Institute of Scientific and Technical Information of China (English)

    许倩; 牛希跃; 张冰冰; 李述刚

    2014-01-01

    Penicillium sp.and Aspergillus niger were isolated from red dates as the tested strains. Through determination of cinnamon oil and perilla oil in different scale, different temperature and different pH conditions, study on inhibition of the two fungi, and on the basis of orthogonal test optimization to determine the optimum inhibited conditions. The test results show that:cinnamon oil to Penicillium sp. minimum inhibitory concentration (MIC) is 0.313μL/mL, Aspergillus niger MIC is 0.156μL/mL, and perilla oil on Penicillium sp. and Aspergillus niger MIC are 10 μL/mL and 5 μL/mL;cinnamon oil and perilla oil in the total content of 0.42 μL/mL, two concentration ratio was 3 ∶ 1, 5 ℃, pH 3 on Penicillium sp. antibacterial circle diameter up to 24 mm, on Aspergillus niger antibacterial circle diameter up to 22.7 mm. The composite essential oils of cinnamon and perilla which has obvious inhibiting effect on Penicillium sp. and Aspergillus niger, is a good storage of Dongzao jujube mildew inhibitor.%以冬枣中常见致病菌青霉(Penicillium sp.)和黑曲霉(Aspergillus niger)为控制对象,通过单因素和正交试验研究不同复配比、不同处理温度和pH条件下肉桂精油和紫苏精油对这两种霉菌的抑制效果。结果表明:(1)肉桂精油对青霉和黑曲霉的最小抑菌浓度(MIC)分别为:0.313μL/mL和0.156μL/mL;紫苏精油对青霉和黑曲霉的MIC分别是10μL/mL和5μL/mL;(2)肉桂精油与紫苏精油在总含量为0.42μL/mL,复配比为3∶1,处理温度为5℃和pH为3时抑菌效果最好,对青霉和黑曲霉的最大抑菌圈直径可高达24 mm和22.7 mm。说明复配精油对青霉和黑曲霉均有明显的抑制作用,是一种良好的冬枣贮藏霉菌抑制剂。

  4. Biodegradation of low-density polyethylene (LDPE by mixed culture of Lysinibacillus xylanilyticus and Aspergillus niger in soil.

    Directory of Open Access Journals (Sweden)

    Atefeh Esmaeili

    Full Text Available In this study, two strains of Aspergillus sp. and Lysinibacillus sp. with remarkable abilities to degrade low-density polyethylene (LDPE were isolated from landfill soils in Tehran using enrichment culture and screening procedures. The biodegradation process was performed for 126 days in soil using UV- and non-UV-irradiated pure LDPE films without pro-oxidant additives in the presence and absence of mixed cultures of selected microorganisms. The process was monitored by measuring the microbial population, the biomass carbon, pH and respiration in the soil, and the mechanical properties of the films. The carbon dioxide measurements in the soil showed that the biodegradation in the un-inoculated treatments were slow and were about 7.6% and 8.6% of the mineralisation measured for the non-UV-irradiated and UV-irradiated LDPE, respectively, after 126 days. In contrast, in the presence of the selected microorganisms, biodegradation was much more efficient and the percentages of biodegradation were 29.5% and 15.8% for the UV-irradiated and non-UV-irradiated films, respectively. The percentage decrease in the carbonyl index was higher for the UV-irradiated LDPE when the biodegradation was performed in soil inoculated with the selected microorganisms. The percentage elongation of the films decreased during the biodegradation process. The Fourier transform infra-red (FT-IR, x-ray diffraction (XRD and scanning electron microscopy (SEM were used to determine structural, morphological and surface changes on polyethylene. These analyses showed that the selected microorganisms could modify and colonise both types of polyethylene. This study also confirmed the ability of these isolates to utilise virgin polyethylene without pro-oxidant additives and oxidation pretreatment, as the carbon source.

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

    Directory of Open Access Journals (Sweden)

    Morahem Ashengroph

    2013-01-01

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

  6. Degradation of corn bran by solid-state fermentation using Aspergillus niger%黑曲霉固态发酵及酶解玉米皮

    Institute of Scientific and Technical Information of China (English)

    胡慧东; 许赣荣

    2011-01-01

    The residues of corn bran were used as main substrates for solid-state fermentation (SSF) and the cellulose in corn bran was degraded. The first step was cellulase production with Aspergillus Niger by SSF and the second step was enzymatic degradation of cellulose in corn bran. The PlackettBurman and Response Surface Methods were used for optimization. The fermentation conditions were as follows: temperature 30 ℃, 10% inoculum, initial moisture content of 60% , material thickness of 2.47 cm, pH of 5.79, fermentation time 6 d. The filter paper activity was 1 I. 01 U/g and increased 40.61% higher than the original enzyme activity. pH 4.8 acetate-sodium acetate buffer solution was added after fermentation and enzymolysis at 50 ℃ for 144 h, neutral detergent fiber and acid detergent fiber degradation rates were 46.09% and 48.82 %, respectively, and the reducing sugar content was 9.02 %.%以玉米提取淀粉后的玉米皮渣为主要原料,采用黑曲霉固态发酵法产酶再酶解的二步法降解玉米皮中纤维素类物质.经Plackett-Burman法及响应面设计优化发酵条件得:温度30℃,接种量10%,初始水分体积分数60%,物料厚度2.47 cm,初始pH 5.79,发酵时间6d;滤纸比酶活可达11.01 U/g,较原始酶活提高了40.61%;产酶结束后加入pH4.8醋酸-醋酸钠缓冲液,置于50℃下酶解144 h,中性洗涤纤维与酸性洗涤纤维降解率分别为46.09%、48.82%,还原糖质量分数达到9.02%.

  7. 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...

  8. Identification of a classical mutant in the industrial host Aspergillus niger by systems genetics: LaeA is required for citric acid production and regulates the formation of some secondary metabolites

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jing; Arentshorst, Mark; Nair, Deepa; Dai, Ziyu; Baker, Scott E.; Frisvad, Jens; Nielsen, Kristian F.; Punt, Peter J.; Ram, Arthur F.

    2016-01-11

    Rapid acidification of the culture medium by the production of organic acids and the production of acid-induced proteases are key characteristics of the filamentous fungus Aspergillus niger. The D15 mutant of A. niger is non-acidifying mutant and used often for the expression of recombinant proteins in A. niger, because of its reduced production of extracellular proteases under non-acidic conditions. In this study, the D15 mutant is characterized in detail. Strongly reduced levels of citric and oxalic acid were observed in the D15 mutant both in shake flask cultures and in controlled batch cultivations. To identify the mutation in the D15 mutant, we successfully combined high-throughput sequencing (Illumina) with bulk segregant analysis. Because of the lack of a sexual cycle for A. niger, the parasexual cycle was used to generate a pool of segregants. From the 52 single nucleotide polymorphisms (SNPs) between the parental strains, three SNPs were homozygous in the genomic DNA of pool of segregants. These three SNPs mapped to all the right arm of chromosome II, indicating that this region contains the genetic locus affecting the phenotype related to acid production. Of the three SNPs, one mutation resulted in a missense mutation in the gene encoding the A. niger homologue of the A. nidulans methyltransferase gene laeA. Complementation analysis of the original mutant with the laeA gene and targeted disruption of laeA further confirmed that LaeA is involved in citric acid production in A. niger lab (N402) and citric acid production strains (ATCC 11414). Analysis of the secondary metabolite (SM) profile of the laeA mutants indicate that LaeA is required for the production of several SMs (asperrubrol, atromentin and JBIR86), but deletion of laeA also resulted in the presence of SMs (aspernigrin A/B and BMS-192548) that were not detected in the wild-type strain. The levels of ten other SMs were not strongly affected as a result of laeA deletion indicating that only a

  9. Production of Fructooligosaccharides using Free-whole-cell Biotransformation by Aspergillus niger CGMCC No.6640%Aspergillusniger CGMCC No.6640全细胞生物转化制备蔗果低聚糖

    Institute of Scientific and Technical Information of China (English)

    周康; 刘冬梅; 范梦珂; 叶嘉伦

    2013-01-01

    Fructooligosaecharides (FOS) have received particular interest because of their excellent biological and functional properties for using as a prebiotic compound.The strain Aspergillus niger CGMCC No.6640 with independent intellectual property rights was found capable of producing FOS using sucrose as the substrate.To produce FOS using free-whole-cell biotransformation by A.niger 6640,the effects of production parameters on the biotransformation of sucrose were investigated by HPLC with the column of Rezex RCM-Monosaccharife Cat.The catalysate concentration of the Nystose (or 1F-Fructofuranosylnystose),kestose,sucrose,glucose and fructose were simultaneously detected,and their retention time was 8.403 min,8.853 min,9.705 min,11.473 min and 14.683 min,respectively.The free-whole-cell concentration and substrate concentration positively affected the maximum FOS yield.However CaCl2 concentration negatively affected the FOS yield.The free-whole-cell concentration,the initial reaction pH,the temperature for catalysis,biotransformation time and sucrose concentration were 60g/L,7.0,33 ℃,40 h and 600 g/L,respectively.Under the optimal conditions were as follows,the FOS contents reached 314.60 g/L.In summary,the free-whole-cell biocatalyst of A.niger 6640 can effectively produce FOS indicating a potential for industrial production.%蔗果低聚糖(FOS)作为一种益生元物质,由于其具有极好的生物和功能性质,受到人们极大的关注.具有独立知识产权的菌株Aspergillus niger CGMCC No.6640被发现能利用蔗糖制备FOS.为利用A.niger 6640的全细胞制备FOS,以蔗糖为底物,利用高效液相法对该菌株的全细胞生物转化参数进行了研究.利用色谱柱Rezex RCM-Monosaccharife Cat的高效液相法能同时检测催化产物中蔗果四糖(或蔗果五糖)、蔗果三糖、蔗糖、葡萄糖和果糖的浓度,其保留时间分别为8.403 min,8.853 min,9.705 rmin,11.473min和14.683 min.全细胞生物催化剂浓度和底

  10. 响应面法优化黑曲霉发酵产低聚异麦芽糖培养基%Response Surface Methodology for Optimization of Medium Composition for Isomaltooligosaccharide Production by Aspergillus niger CU-1

    Institute of Scientific and Technical Information of China (English)

    吴孔阳; 王学军; 周培华; 黄时海; 张云开; 陈桂光; 梁智群

    2012-01-01

    采用全因子试验、最陡爬坡试验以及Box—Behnken试验设计对黑曲霉CU-1(Aspergillus nigerCU-1)发酵生产低聚异麦芽糖培养基的主要成分进行优化。结果表明:最优培养基成分为:麸皮浸汁体积分数4%、玉米浆添加量19.67g/L、NaNO3添加量2.24g/L、木薯淀粉糖化液添加量250g/L,在该培养条件下,在3.6L发酵罐中进行验证,发酵液中异麦芽糖、潘糖和异麦芽三糖总产量达到37.4%,低聚异麦芽糖总产量高达83.1%,说NBox—Behnken试验设计法用于黑曲霉发酵生产低聚异麦芽糖培养基优化是可行的,数学模型的预测值与实验观察值相符。%The major fermentation medium components for isomaltooligosaccharide production by Aspergillus niger CU-1 were optimized by full factorial, steepest ascent and Box-Behnken designs. The optimal medium components were determined to be 4% wheat bran extract, 19.67 g/L corn steep liquor, 2.24 g/L NaNO3, and 250 g/L saccharified cassava starch. Fermentation of the optimized medium by Aspergillus niger CU-1 was carried out in a 3.6 L fermenter to obtain isomaltose, panose and isomaltotriose yield as high as 37.4%, an isomaltooligosaccharide yield as high as 83.1%. The good agreement between the predictive and actual values indicated that the mathematical model established based on Box- Behnken design was valid.

  11. Nariginase of Aspergillus niger: Production optimization by response surface methodology and utilisation of ultrasound for extractionNaringinase de Aspergillus niger: Otimização da produção por metodologia de superfície de resposta e uso do ultrassom para extração

    Directory of Open Access Journals (Sweden)

    Maria Antonia Pedrine Colabone Celligoi

    2011-08-01

    Full Text Available Brazil is the world's largest producer of orange and concentrated juice for export. Concentrated juice with high levels of naringin has excessive bitterness, which reduces the quality and value on the market. The debittering can be obtained by using naringinase, an enzymatic complex that degrades naringin. This study reports the production of naringinase by Aspergillus niger 426 utilizing both sugar cane molasses as carbon source and yeast extract as nitrogen source. Naringin was used as inducer. Five nitrogen sources were studied and yeast extract was found as the best one as 225.6 mU/mL of naringinase activity at 120 hours of fermentation was achivied. For optimization of naringinase production it was applied response-surface methodology, with 22 incomplete factorial design. An activity value of 354.26 mU/mL of naringinase was achivied when as independent variables yeast extract (14.0g/L and naringin (0.2g/L were used. When applied ultrasound waves at 20 kHz of intensity for 2 minutes in the fermented broth, the activity reached the highest value of 473.6 mU/mL. Thus, naringinase, this enzyme of great potential for biotechnological applications, has its production increased by using statistical design and ultrasound.O Brasil é o maior produtor mundial de laranja e de suco concentrado destinado à exportação. Sucos cítricos concentrados para exportação com níveis elevados de naringina são excessivamente amargos, o que reduz a qualidade e o valor comercial do produto. A redução do amargor pode ser obtida pela naringinase, um complexo enzimático que degrada a naringina. Neste trabalho Aspergillus niger 426 foi usado como produtor de naringinase utilizando matérias-prima da agroindústria, melaço como fonte de carbono e extrato de levedura como fonte de nitrogênio. Naringina foi usada como indutor. Dentre as cinco fontes de nitrogênio pesquisadas, extrato de levedura apresentou o melhor resultado de 225,6 mU/mL de naringinase em 120

  12. Treatment of both native and deamidated gluten peptides with an endo-peptidase from Aspergillus niger prevents stimulation of gut-derived gluten-reactive T cells from either children or adults with celiac disease

    DEFF Research Database (Denmark)

    Toft-Hansen, Henrik; Rasmussen, Karina Søndergård; Nielsen, Anne Staal;

    2014-01-01

    Celiac disease (CD) is characterized by an inappropriate immunological reaction against gluten driven by gluten-specific CD4+ T cells. We screened 25 proteases and tested 10 for their potential to degrade gluten in vitro. Five proteases were further tested for their ability to prevent the...... proliferative response by a gluten-specific CD4+ T cell clone and seven gluten-reactive T cell lines to protease-digested gluten peptides. A proline-specific endo-peptidase from Aspergillus niger (AnP2), was particularly efficient at diminishing proliferation after stimulation with cleaved antigen, and could...... completely block the response against both native and deamidated gluten peptides. We found that AnP2 was efficient down to a 1:64 protease:substrate ratio (w:w). When AnP2 was tested in assays using seven gluten-reactive T cell lines from individual CD patients (three adults and four children), the response...

  13. Removal of Heavy Metals from Urban Sewage by Aspergillus Niger and Pseudomonas Fluorescens%黑曲霉、荧光假单胞菌去除污水中重金属试验研究

    Institute of Scientific and Technical Information of China (English)

    李海华; 白国强; 付莹莹; 金艳艳

    2011-01-01

    将黑曲霉和荧光假单胞菌引入到传统的卡鲁塞尔氧化沟工艺模型中,参照规范中氧化沟的水力停留时间,分别选取12、16、20、24、28、32和36 h水力停留时间进行试验,研究了不同水力停留时间2种菌种对重金属Cd、Cr、Pb和Cu的吸附降解规律.对水力停留时间为36 h进行了接种对比试验研究.研究发现接种2种菌种后,当水力停留时间为20 h时,黑曲霉对4种重金属的去除率达到52%~91%.荧光假单胞菌对4种重金属的去除率均达到70%以上,去除效果非常显著,而这个时间参数也正是氧化沟常规的设计参数,由此可以说明,将黑曲霉和荧光假单胞菌引入到城市污水处理工艺中,可以明显提高常规工艺对重金属的吸附降解效率.%Aspergillus niger and Pseudomonas fluorescens were inoculated to the activated sludge in order to improve the removal effectiveness of the oxidation ditch. The comparative experimental study were car ried out when the Hydraulic Retention Time (HRT) was 36 h, and six different HRT of 12 h, 16 h, 20 h, 24 h, 28 h, and 32 h were considered to study the adsorption degradation of Cd, Cr, Pb and Cu by Asper gillus niger and Pseudomonas fluorescens in the oxidation ditch. The result indicated that each of the two strains removal efficiency of the four heavy metals compared with the control group was significantly im proved, and the removal increased with the increasing HRT. When the HRT was 20 h, the removal effi ciency of the four heavy metals by the Aspergillus niger were found to be in the range of 52% to 91%, and the removal efficiency by Pseudomonas fluorescens reached 70%. Most of the heavy metals can be degrad ed in the HRT of 20 h, and this time parameter is exactly the conventional design parameters of oxidation ditch. It can be say that the degradation efficiency of adsorption of heavy metals can be significantly im proved when inoculated with Aspergillus niger and Pseudomonas

  14. A single mutation in the hepta-peptide active site of Aspergillus niger PhyA phytase leads to myriad of biochemical changes

    Science.gov (United States)

    The active site motif of proteins belonging to ‘Histidine Acid Phosphatase’ (HAP) contains a hepta-peptide region, RHGXRXP. A close comparison among fungal and yeast HAPs has revealed the fourth residue of the hepta-peptide to be E instead of A, which is the case with A. niger phyA phytase. However,...

  15. Formation of Aspergillus niger-mineral aggregation and characterization of polysaccharide from aggregation%黑曲霉-矿物聚集体的形成及其分泌的多糖特性

    Institute of Scientific and Technical Information of China (English)

    胡婕; 连宾; 郁建平; 胡星

    2011-01-01

    [Objective]In order to understand the weathering on potassium-bearing mineral by Aspergillus niger, we studied the formation of A.niger-mineral aggregation and polysaccharide in the revolving and fermenting mode and their role in the process of weathering on potassium-bearing mineral.[Methods]We used four different media to study the morphology of A.niger-mineral aggregation; ultraviolet-visible spectrum ( UV-Vis ) , fourier transform infrared spectrum (IR), gas chromatography( GC) , scanning electron microscopy ( SEM ) and energy dispersive spectrometer ( EDS ) were combined to research the changes of polysaccharide and their significances in the micro-environment forming fungal-mineral aggregation.[Results]A, niger myclia intertwined, adsorbed and bonded mineral powder to form aggregation by the assistance of polysaccharide and other metabolites.After formation of the aggregation, the concentration and structure of polysaccharide were changed significantly.[Conclusion]The changes of polysaccharide would enhance the adsorption on minerals , chelation on metal ions and adsorption on water molecules, which provided a favorable micro-environment for the fungal using mineral nutrients effectively.%[目的]为深入理解黑曲霉(Aspergillus niger)对含钾矿粉的风化作用,研究在旋转发酵方式下形成的黑曲霉-矿物聚集体及其多糖,并分析它们在含钾矿粉风化过程中的作用.[方法]采用不同组合培养基,研究黑曲霉-矿物聚集体的形成和形貌;联合紫外-可见分光光谱(UV-Vis)、傅立叶变换红外光谱(FT-IR)、气相色谱(GC)、电子扫描显微镜(SEM)、x射线能谱仪(EDS)等分析手段研究黑曲霉-矿物聚集体形成前后微环境中多糖的变化以及这种改变对风化产生的意义.[结果]黑曲霉菌丝与矿粉在多糖等代谢产物帮助下,通过相互缠绕、吸附、粘合等作用形成黑曲霉-矿物聚集体,聚集体形成前后多糖浓度和多糖结构均发生显著

  16. Factors influencing leaching of uranium ore by organic acids from Aspergillus niger%黑曲霉产有机酸浸出铀矿石的影响因素

    Institute of Scientific and Technical Information of China (English)

    王永东; 李广悦; 丁德馨; 胡南; 邓钦文; 周支香

    2012-01-01

    Leaching uranium ores by fungi is a promising new bioleaching approach, and organic acids play key roles. However, little is known about the relationships between uranium leaching rate and organic acids produced by fungi. To explore the effects of medium types, culture temperature and pH value on uranium leaching by organic acids from Aspergillus niger, a strain of them was separated and purified from some water samples from a uranium mine. PSA and PCS medium were used for culture of Aspergillus niger, and mixed organic acids with different pH value produced by Aspergillus niger at diverse culture temperature were obtained and applied to tests of uranium leaching. The results show that leaching rate of uranium has statistically significant difference for these organic acids produced at different conditions, because there are different ingredients in these organic acids. All factors including of medium type, culture temperature and pH could influence composition and quantity of mixed organic acids. When Aspergillus niger was cultured in different medium, the composition of mixed organic acids is different, mainly oxalic acid and citric acid, and uranium leaching rates also different. Uranium leaching is better for the products obtained in PSA medium than in PCS one no matter different pH and culture temperature (p<0. 05). For same medium, due to difference in pH value culture temperature uranium leaching rate is also different (p<0.05). For example, for PSA the best culture temperature and pH value are 25℃ and 2.3 respectively, and mean uranium leaching rate were 76.14% and 82.40% at these conditions. While for PCS, the best conditions were 30℃ and 2.0, and the mean uranium leaching rate were 56.60% and 67.91%, respectively. The results also show that there are interaction effects between culture temperature and pH value of mixed organic acids (p<0. 05). Main factor influencing uranium leaching rate is pH value, and the second their interaction effects. Culture

  17. The Effect of Microwave-NaOH Pretreatment and Hydrolysis Enzyme Using Trichoderma reesei-Aspergillus niger on Rice Straw Bioethanol Production

    Directory of Open Access Journals (Sweden)

    Bambang Dwi Argo

    2016-01-01

    Full Text Available The process of bioethanol production from rice straw consists of two steps: (1 conversion of cellulose into simple sugars which is conducted by using microwave-NaOH pretreatment and straw hydrolysis using mold catalyst T.reesei and A. niger; and (2 fermentation of simple sugars into ethanol. In a microwave-NaOH pretreatment process has been obtained the best value content of cellulose in straw size of 100 mesh and a long exposure of 40 minutes for 72.70+1:10%. Crude cellulase enzyme activity of T.reesei isolation, A.niger and it mixtures were optimum at temperature of 50°C. The addition of crude enzyme from A.niger and T.reesei on a comparison of 1: 2 (v/v was able to increase the yield of the rice straw cellulose hydrolysis which is produces sugar at 12.89 mg/ml (1.29% w/v or 0.15% (w/v when converted into ethanol. The glucose yield from rice straw was 25.47% with 3% ethanol.

  18. Inhibitory Effects of Tea Tree Oil, Eugenol and Citral on Aspergillus niger in Litchi%茶树油、丁香酚和柠檬醛志荔枝黑曲霉的抑制作用

    Institute of Scientific and Technical Information of China (English)

    钟业俊; 徐欣源; 刘成梅; 孙健; 吴建永; 刘桃英

    2012-01-01

    研究茶树油、丁香酚和柠檬醛的挥发性香氛对荔枝致腐真菌黑曲霉的抑制作用,采用复配方法探究3种香料对黑曲霉的协同抑菌性。结果表明:丁香酚和柠檬醛的挥发性香氛对黑曲霉有较强的抑制作用,最低抑菌浓度分别为0.3μL/cm^3和0.4μL/cm^3;茶树油挥发性香氛抑制黑曲霉的作用稍差,但与丁香酚和柠檬醛复配后协同抑菌作用增强。%The inhibitory and synergistic inhibitory effects of volatile aromatic components from tea tree oil, eugenol and citral on rot-causing fungi such as AspergiUus niger in litchi were studied. The results showed that the volatile aromatic components from eugenol and citral had strong inhibitory effect on Aspergillus niger with minimum inhibition concentrations of 0.3 μL/cm^3 (air volume) and 0.4 μL/cm^3 (air volume), respectively. The anti-fungal effect of tea tree oil was weak, while its inhibitory effect could be enhanced in the attendance of eugenol and citral.

  19. 黑曲霉耐酸性α-淀粉酶的固态发酵条件研究%Solid State Fermentation of Acid Resistant α-Amylase from Aspergillus Niger

    Institute of Scientific and Technical Information of China (English)

    吴茜茜; 王红梅; 张增辉; 蔡敬民

    2012-01-01

    Solid state fermentation conditions of acid amylase from Aspergillus niger PZ30I were studied. The results showed that the optimal medium contained wheat bran 7. Og, glucose 0. 07g, starch 0. 21g, (NH4)2SO40.07g,optimal initial pH 4.2. Based on the above medium, PZ301 was cultured at 35? for 72 hours with 1:1 of wheat bran to water and inoculation 3mL( 107spores/mL) ,enzyme activity was 19. 6 lU/g dry medium. The biomass curve of PZ301 in solid slate fermentation was determined, and production kinetics was studied through studying the relation between the curve of strain PZ301 and the time of acid stable a-amyl-ase production. The result indicated that the synthesizing type of acid stable ot-amylase was synchronous synthesis model.%研究了固态发酵条件对黑曲霉(Aspergillus niger)PZ301合成酸性α-淀粉酶的影响.结果表明,固态发酵最佳培养基组成:麸皮7.0g,葡萄糖0.07g,淀粉0.21g,(NH4)2SO40.07g,起始pH4.2;最佳培养条件为培养温度35℃,料水比为1∶1,接种量3mL(孢子浓度为10 7个/mL).在上述条件下培养72h,酶活力可达19.6IU/g干培养基.另外还测定了PZ301固态发酵中生物量的变化,PZ301菌株的生物量和耐酸性α-淀粉酶在72h时均达到最高,这表明耐酸性α-淀粉酶系同步合成型酶.

  20. Effectively expression of Thermomyces lanuginosus thermostable lipase in non-spore Aspergillus niger%疏棉状嗜热丝孢菌耐热脂肪酶在无孢黑曲霉中的高效表达

    Institute of Scientific and Technical Information of China (English)

    陈婧; 王斌; 李德明; 潘力

    2012-01-01

    We optimized the codon usage of Thermomyces lanuginosus lipase(tll) gene based on codon usage bias,RNA stability and free energy,and synthesized the optimized tll gene. The obtained tll gene was inserted into a clone vector,and then subcloned to the expression vector pHGWPT-tll. The vector pHGWPT-tll was transformed into non-spore Aspergillus niger SH-2 via Agrobacterium tumefaciens-mediated transformation using hygromycin B resistant gene as the selection marker. A. niger transformants bearing the tll gene,were selected by tributyrin hydrolyzing plate. The recombinant protein was verified by SDS-PAGE and Western blotting. After 72h fermentation,the lipase activity of transformants reached 36U/mL. Furthermore,the tll transformants was subjected to mutagenesis via atmospheric and room temperature plasma (ARTP). The specific activity of the mutants was 37% higher than that of the original transformants,suggesting that tll gene could be highly expressed in A. niger.%综合考虑密码子偏爱性、RNA稳定性以及自由能等因素,对疏棉状嗜热丝孢菌(Thermomyces lanuginosus)耐热脂肪酶(tll)基因序列进行密码子优化并全基因合成。将合成的tll基因连接到克隆载体,然后亚克隆到表达载体pHGWPT-tll,采用根癌农杆菌介导转化无孢黑曲霉SH-2。经过三丁酸甘油酯平板、SDS—PAGE以及Westem Blotting鉴定,成功表达了tll基因。发酵72h,转化子脂肪酶酶活最高达36U/mL。转化子经等离子诱变得到的突变株的脂肪酶比活力比出发菌株提高约37%。

  1. 黑曲霉液体发酵桔粉产纤维素酶的研究%Study on production of celluase by Aspergillus niger with orange powder by liquid fermentation

    Institute of Scientific and Technical Information of China (English)

    董基; 刘钊

    2012-01-01

    With orange powder as raw materials and Aspergillus niger as production strains,cellulase was producted by liquid fermentation.Three important factors of ratio of bran and peptone(C/N),liquid volume in flask,and inoculums size on cellulose activities were researched respectively by single factor test.Based on it,the enzyme production conditions were optimized by orthogonal test.The optimum conditions of enzyme production were adding 80 g/L orange powder,1∶2 ratio of bran and peptone,adding 30 mL Mandels nutrient solution to 250 mL flask,3 mL inoculums size,culturing 72 h at the temperature of 30 ℃.Activities of cellulase producted on the above conditions were 1885.71 U/g.%以桔粉为原料,以黑曲霉(Aspergillus niger)为发酵菌株,采用液体发酵法生产纤维素酶。通过单因素试验考查了麸皮和蛋白胨的比例(C/N)、装液量及接种量3个因素对产酶的影响,并在此基础上,通过正交试验确定了发酵产酶的工艺条件为:添加桔粉80 g/L,麸皮和蛋白胨质量比为1∶2、250 mL三角瓶装30 mL Mandels氏营养液、接种量3 mL,于30℃下培养72 h,纤维素酶产量达到1885.71 U/g。

  2. The Effect of Microwave-NaOH Pretreatment and Hydrolysis Enzyme Using Trichoderma reesei-Aspergillus niger on Rice Straw Bioethanol Production

    OpenAIRE

    Bambang Dwi Argo; Yusuf Hendrawan; Dewi Maya Maharani; Angky Wahyu Putranto; Sri Winarsih

    2016-01-01

    The process of bioethanol production from rice straw consists of two steps: (1) conversion of cellulose into simple sugars which is conducted by using microwave-NaOH pretreatment and straw hydrolysis using mold catalyst T.reesei and A. niger; and (2) fermentation of simple sugars into ethanol. In a microwave-NaOH pretreatment process has been obtained the best value content of cellulose in straw size of 100 mesh and a long exposure of 40 minutes for 72.70+1:10%. Crude cellulase enzyme activit...

  3. Maximization of organic acids production by Aspergillus niger in a bubble column bioreactor for V and Ni recovery enhancement from power plant residual ash in spent-medium bioleaching experiments.

    Science.gov (United States)

    Rasoulnia, P; Mousavi, S M

    2016-09-01

    Spent-medium bioleaching of V and Ni from a power plant residual ash (PPR ash) was conducted using organic acids produced by Aspergillus niger. The production of organic acids in a bubble column bioreactor was optimized through selecting three most influencing factors. Under optimum condition of aeration rate of 762.5(ml/min), sucrose concentration of 101.9(g/l) and inoculum size of 40(ml/l), respectively 17,185, 4539, 1042 and 502(ppm) of oxalic, gluconic, citric and malic acids were produced. Leaching experiments were carried out using biogenic produced organic acids under leaching environment temperature of 60°C and rotary shaking speed of 135rpm, with various pulp densities of 1, 2, 3, 5, 7 and 9(%w/v). The results showed that biogenic produced organic acids leached V much more efficiently than Ni so that even at high pulp density of 9(%w/v), 83% of V was recovered while Ni recovery yield was 30%. PMID:27295250

  4. Production and characterization of enzymatic cocktail produced by Aspergillus niger using green macroalgae as nitrogen source and its application in the pre-treatment for biogas production from Ulva rigida.

    Science.gov (United States)

    Karray, Raida; Hamza, Manel; Sayadi, Sami

    2016-09-01

    Marine macroalgae are gaining more and more importance as a renewable feedstock for durable bioenergy production, but polysaccharides of this macroalgae are structurally complex in its chemical composition. The use of enzymatic hydrolysis may provide new pathways in the conversion of complex polysaccharides to fermentable sugars. In this study, an enzymatic cocktail with high specificity was first isolated from Aspergillus niger using the green macroalgae Ulva rigida as nitrogen source. The cocktail is rich on β-glucosidase, pectinase and carboxy-methyl-cellulase (CMCase). The highest activity was obtained with β-glucosidase (109IUmL(-1)) and pectinase (76IUmL(-1)), while CMCase present the lowest activity 4.6IUmL(-1). The U. rigida pre-treatment with this enzymatic cocktail showed high rate of reduced sugar release, and could bring promising prospects for enzymatic pre-treatment of the biogas production from U. rigida biomass which reached 1175mLgCODint(-1). PMID:27285578

  5. Evaluation of temperature and moisture response surface on the lipase from pumpkin seeds fermentation using Aspergillus niger - doi: 10.4025/actascitechnol.v34i3.12497

    Directory of Open Access Journals (Sweden)

    Rafaela Cristiane Andrade Santos

    2012-05-01

    Full Text Available Agro-industrial waste has shown great potential for use in solid-state fermentation due to its low cost and promoting the growth of microorganisms. This study evaluated the interaction between temperature and moisture response surface on lipase from the fermentation of pumpkin seed flour, using Aspergillus niger. Fermentations were performed in Petri dishes in an experimental design using a 22 matrix with four replications at the center point and four axial points, varying substrate moisture between 30 and 60% and temperature between 30 and 40ºC. The maximum hydrolytic activity (71.88 U g-1 dry weight was obtained using flour with 30% moisture and 30°C temperature in 120 hours of fermentation. The interaction between fermentation temperature and initial moisture content of the residue was the parameter that most influenced the process at 95% significance level. The response surface analysis showed that the maximum lipase production can be obtained under temperature and moisture conditions of the flour ranging from 28 to 34.5°C and 25 to 32.5%; or between 32 and 40°C and 58 and 65%, respectively. Pumpkin seed flour showed potential for obtaining microbial lipase.  

  6. 内切葡聚糖酶基因在黑曲霉中的同源表达%Endo-glucanase gene homologous expressed in Aspergillus niger

    Institute of Scientific and Technical Information of China (English)

    李杰; 高博; 江连洲; 刘君; 邓晨旭; 陈璐璐; 张会

    2014-01-01

    An endo-glucanase can truncate long chains of cellulose in cellulose non-crystal ine region through random hydrolysis of β-1, 4-glycosidic linkage, which plays an important role in the overal degradation of cellulose. In order to improve the endo-glucanase activity of Aspergil us niger, a gene designated Eng1 encoding an endo-glucanase from Aspergil us niger CICC2462 was cloned by using the reverse transcription PCR method. Using the highly expressed elment of glaA encoding a glucoamylase, the recombinant expression vector pSZHG-Eng1 was constructed and transformed into the strain CICC2462 via the Agrobacterium-mediated method. Two strains were obtained by screening hygromycin resistant mutants and base pair substitution based on homologous recombination was established by PCR to exist in glaA gene loci gene. Under the shaking flask fermentation condition, the endo-glucanase activity of the A.niger transformant reached 272 U·mL-1 in the fermentation solution, which was 5.2-fold as high as that of the original strain. The approximately 36 ku protein band from two strains was observed on the SDS-PAGE, and the expressed enzyme was quantitated to be 165-193μg·mL-1. This results showed that the endo-glucanase gene was successful y transformed and homologously expressed in Aspergil us niger, which laid the foundation for the construction of an engineered strain to produce a food-grade endo-glucanase in large-scale industrial production.%内切葡聚糖酶作用于纤维素的非结晶区,随机水解β-1,4-糖苷键,将长链的纤维素截断,对纤维素的整体降解起重要作用。研究从黑曲霉CICC2462中扩增得到内切葡聚糖酶基因Eng1,并针对黑曲霉中高表达的糖化酶基因glaA位点,构建Eng1基因表达载体pSZHG-Eng1,进一步通过农杆菌介导法转化黑曲霉CICC2462。经潮霉素筛选和PCR鉴定获得2株在glaA基因位点发生基因置换的同源重组转化子。在摇瓶发酵条件下,发酵液上

  7. IN VITRO BIOACTIVITY OF CREOSOTE BUSH EXTRACTS (LARREA TRIDENTATA ON THE INHIBITION OF POSTHARVEST FUNGI: PENICILLIUM POLONICUM, ASPERGILLUS NIGER, RHIZOPUS ORYZAE Y ALTERNARIA TENUISSIMA

    Directory of Open Access Journals (Sweden)

    O. Peñuelas-Rubio

    2015-11-01

    Full Text Available En el presente estudio se evaluó la eficiencia de extractos vegetales deLarrea tridentataobtenidos con diclorometano, etanol, metanol y agua, sobre el crecimiento radial in vitro de cuatro hongos fitopatógenos, los cuales primeramente fueron identificados en género y especie empleando claves taxonómicas y técnicas moleculares. Para los bioensayosin vitrose aplicaron diseños completamente al azar con cuatro tratamientos y tres repeticiones en cada hongo, utilizando las concentraciones: 0, 250, 500 y 750 ppm paraAlternaria sp.; 0, 2000, 2500 y 3000 paraAspergillus sp.; 0, 1500, 1750 y 2000 paraPenicillium sp. y 0, 150, 200 y 250 ppm paraRhizopus sp. Cada tratamiento tuvo tres repeticiones. El análisis molecular determinó la especie tenuissima paraAlternaria,nigerparaApergillus,polonicumparaPenicilliumyoryzaeparaRhizopus. En cuanto a las pruebasin vitro, se determinaron inhibiciones del 100% para tres de los hongos en estudio:Alternaria tenuissimacon extracto EtOH a 750 ppm;Aspergillus nigercon extracto DCM a 3000 ppm yRhizopus oryzaea partir de 150 ppm y 250 ppm de los extractos DCM y EtOH respectivamente. Se presentó una inhibición del 82% a 2000 ppm paraPenicillium polonicum. Se concluye que a pesar de las diferencias en susceptibilidad entre las especies fúngicas, los extractos deLarrea tridentataobtenidos con etanol y dicloromentano son efectivos para el control de los hongos fitopatógenos bajo estudioin vitro.

  8. The Transcriptional Repressor TupA in Aspergillus niger Is Involved in Controlling Gene Expression Related to Cell Wall Biosynthesis, Development, and Nitrogen Source Availability

    DEFF Research Database (Denmark)

    Schachtschabel, Doreen; Arentshorst, Mark; Nitsche, Benjamin M; Morris, Sam; Nielsen, Kristian Fog; van den Hondel, Cees A M J J; Klis, Frans M; Ram, Arthur F J

    2013-01-01

    of the agsA gene. The agsA gene encodes a putative alpha-glucan synthase, which is induced in response to cell wall stress in A. niger. Apart from the constitutive expression of agsA, the selected mutant was also found to produce an unknown pigment at high temperatures. Complementation analysis with......A mutants were very similar to the phenotypes of a tupA deletion strain. Further analysis of the tupA-17 mutant and the ΔtupA mutant revealed that TupA is also required for normal growth and morphogenesis. The production of the pigment at 37°C is nitrogen source-dependent and repressed by ammonium. Genome......-wide expression analysis of the tupA mutant during exponential growth revealed derepression of a large group of diverse genes, including genes related to development and cell wall biosynthesis, and also protease-encoding genes that are normally repressed by ammonium. Comparison of the transcriptome of up...

  9. The use of 32P dilution techniques to evaluate the effect of mycorrhizal inoculation on plant uptake of P from products of fermentation mixtures including agrowastes, Aspergillus niger and rock phosphate

    International Nuclear Information System (INIS)

    Some microorganisms, such as filamentous fungi, are capable of solubilizing rock phosphate products, which are a less costly alternative to conventional P fertilizers used so far in agriculture. However, metabolizable C compounds must be supplied to the microbes to solubilize rock phosphate (RP). On another hand, huge quantities of organic materials are produced by cultivated plants every year and their residues became agrowastes, which may often pose significant environmental problems. An attractive approach to solubilize RP would therefore, be the application of microorganisms possessing a high acid-producing activity in fermentation processes based on agrowastes. In this context, Aspergillus niger was successfully cultivated on sugar beet (SB) waste material supplemented with 3.0 g/l RP acidifying the medium by releasing citric acid and thus decreasing the pH to 3.0-3.5. At the end of the solid-state fermentation process, the product contained mineralized (69%) organic matter, RP solubilized to 224 μg/ml and fungal mycelium. A series of microcosms greenhouse experiments were then carried out aimed at evaluating the effectiveness of such product, added at a rate of 5% (v/v), to a neutral, calcareous, P-deficient soil. Clover (Trifolium repens) inoculated or not with an arbuscular mycorrhizal fungus, was the test plant. It was shown that the product improved plant growth and P acquisition. Mycorrhizal inoculation further enhanced the effectiveness of the fermentation product. The use of the isotopic 32 P dilution technique showed a lowering of the specific activity of the treated plants, thus indicating that plants benefited from P solublilized from RP by the microbial treatments applied in this experiment. The reported biotechnological approach offers a potential application for sustainability purposes. (author)

  10. The use of 32P dilution techniques to evaluate the effect of mycorrhizal inoculation on plant uptake of P from products of fermentation mixtures including agrowastes, Aspergillus niger and rock phosphate

    International Nuclear Information System (INIS)

    Some microorganisms, such as filamentous fungi, are capable of solubilizing rock phosphate products, which are a less costly alternative to conventional P fertilizers used so far in agriculture. However, metabolizable C compounds must be supplied to the microbes to solubilize rock phosphate (RP). On another hand, huge quantities of organic materials are produced by cultivated plants every year and their residues became agrowastes, which may often pose significant environmental problems. An attractive approach to solubilize RP would therefore, be the application of microorganisms possessing a high acid-producing activity in fermentation processes based on agrowastes. In this context, Aspergillus niger was successfully cultivated on sugar beet (SB) waste material supplemented with 3.0 g/l RP acidifying the medium by releasing citric acid and thus decreasing the pH to 3.0-3.5. At the end of the solid-state fermentation process, the product contained mineralized (69%) organic matter, RP solubilized to 224 μg/ml and fungal mycelium. A series of microcosms greenhouse experiments were then carried out aimed at evaluating the effectiveness of such product, added at a rate of 5% (v/v), to a neutral, calcareous, P-deficient soil. Clover (Trifolium repens) inoculated or not with an arbuscular mycorrhizal fungus, was the test plant. It was shown that the product improved plant growth and P acquisition. Mycorrhizal inoculation further enhanced the effectiveness of the fermentation product. The use of the isotopic 32 P dilution technique showed a lowering of the specific activity of the treated plants, thus indicating that plants benefited from P solubilized from RP by the microbial treatments applied in this experiment. The reported biotechnological approach offers a potential application for sustainability purposes. (author)

  11. Two-stage statistical medium optimization for augmented cellulase production via solid-state fermentation by newly isolated Aspergillus niger HN-1 and application of crude cellulase consortium in hydrolysis of rice straw.

    Science.gov (United States)

    Sandhu, Simranjeet Kaur; Oberoi, Harinder Singh; Babbar, Neha; Miglani, Kanupriya; Chadha, Bhupinder Singh; Nanda, Dhiraj Kumar

    2013-12-26

    Cellulolytic enzyme production by newly isolated Aspergillus niger HN-1 was statistically optimized using Plackett-Burman and central composite design (CCD). Optimum concentrations of 2, 0.40, 0.01, and 0.60 g L (-1) for KH2PO4, urea, trace elements solution, and CaCl2·2H2O, respectively, were suggested by Design-Expert software. The two-stage optimization process led to a 3- and 2-fold increases in the filter paper cellulase (FP) and β-glucosidase activities, respectively. FP, β-glucosidase, endoglucanase, exopolygalaturonase, cellobiohydrolase, xylanase, α-l-arabinofuranosidase, β-xylosidase, and xylan esterase activities of 36.7 ± 1.54 FPU gds(-1), 252.3 ± 7.4 IU gds(-1), 416.3 ± 22.8 IU gds(-1), 111.2 ± 5.4 IU gds(-1), 8.9 ± 0.50 IU gds(-1), 2593.5 ± 78.9 IU gds(-1), 79.4 ± 4.3 IU gds(-1), 180.8 ± 9.3 IU gds(-1), and 288.7 ± 11.8 IU gds(-1), respectively, were obtained through solid-state fermentation during the validation studies. Hydrolysis of alkali-treated rice straw with crude cellulases resulted in about 84% glucan to glucose, 89% xylan to xylose, and 91% arabinan to arabinose conversions, indicating potential for biomass hydrolysis by the crude cellulase consortium obtained in this study. PMID:24328069

  12. In vitro and in vivo effects of Pseudomonas spp. and Bacillus sp. on Fusarium acuminatum, Botrytis cinerea and Aspergillus niger infecting cucumber

    Directory of Open Access Journals (Sweden)

    Jasmina Zdravković

    2015-09-01

    Full Text Available Cucumber (Cucumis sativus L is an important member of the Cucurbitaceae family. Production of healthy nursery is necessary for high-quality production of this crop in greenhouses and in fields. With the idea of minimizing the use of pesticides and mineral fertilizers to preserve soil quality, we investigated the effects of plant growth promoting bacteria (PGPB on growth promotion and protection of cucumber plants from phytopathogenic fungi. The effects of Pseudomonas spp. strains with different antifungal activities and Bacillus sp. Q10 strain with PGP activity were tested on cucumber plants. Antagonistic activity of Pseudomonas spp. against the growth of several phytopathogenic fungi isolated from cucumber: F. acuminatum, B. cinerea and A. niger, was observed. The influences of overnight cultures, supernatants and heat-stable antifungal factors were tested on the phytopathogenic fungi in vitro. Pseudomonas sp. K35 and K24 strains were more effective than P. chlororaphis Q16 and Pseudomonas sp. K27, showing 70-80% of fungal growth inhibition regardless of culture or fraction applied. The good antagonists that belong to pseudomonads and Bacillus sp. Q10 strain were used as mixtures for estimation of plant growth and health promoting effects on cucumber plants. Growth dynamics differed depending on the applied strain of Pseudomonas sp. The M3 treatment (a mixture of Bacillus sp. Q10 and P. chlororaphis Q16 stimulated the initial phase of growth, while M4 (a mixture of Bacillus sp. Q10 and Pseudomonas sp. K24 resulted in the maximal height at the final measurement. Significant differences in leaf and plant weight (M4, and leaf weight (M5, containing K35 strain were found after the treatments. No significant differences in chlorophyll and NBI level were observed in any of the tested combinations. The obtained results suggested that M3 was suitable for stimulation of the early phase of cucumber growth, while the mixtures M4 and M5 improved plant

  13. Morphological development of Aspergillus niger in submerged citric acid fermentation as a function of the spore inoculum level. Application of neural network and cluster analysis for characterization of mycelial morphology

    Directory of Open Access Journals (Sweden)

    Mattey Michael

    2006-01-01

    Full Text Available Abstract Background Although the citric acid fermentation by Aspergillus niger is one of the most important industrial microbial processes and various aspects of the fermentation appear in a very large number of publications since the 1950s, the effect of the spore inoculum level on fungal morphology is a rather neglected area. The aim of the presented investigations was to quantify the effects of changing spore inoculum level on the resulting mycelial morphology and to investigate the physiology that underlines the phenomena. Batch fermentations were carried out in a stirred tank bioreactor, which were inoculated directly with spores in concentrations ranging from 104 to 109 spores per ml. Morphological features, evaluated by digital image analysis, were classified using an artificial neural network (ANN, which considered four main object types: globular and elongated pellets, clumps and free mycelial trees. The significance of the particular morphological features and their combination was determined by cluster analysis. Results Cell volume fraction analysis for the various inoculum levels tested revealed that by rising the spore inoculum level from 104 to 109 spores per ml, a clear transition from pelleted to dispersed forms occurs. Glucosamine formation and release by the mycelium appears to be related to spore inoculum level. Maximum concentrations detected in fermentations inoculated with 104 and 105 spores/ml, where pellets predominated. At much higher inoculum levels (108, 109 spores/ml, lower dissolved oxygen levels during the early fermentation phase were associated with slower ammonium ions uptakes and significantly lower glucosamine concentrations while the mycelium developed in dispersed morphologies. A big increase in the main and total hyphal lengths and branching frequency was observed in mycelial trees as inoculum levels rise from 104 to 109 spores/ml, while in aggregated forms particle sizes and their compactness decreased

  14. Study on amylase production from solid-state fermentation of notoginseng residues by Aspergillus niger%黑曲霉固态发酵三七渣产淀粉酶的研究

    Institute of Scientific and Technical Information of China (English)

    胡伟; 谭显东; 王君君; 羊依金; 罗明江; 张伟

    2013-01-01

    以三七渣为基质,采用黑曲霉固态发酵产淀粉酶,考察了硫酸铵(氮源)添加量、三七渣粒径、固体培养基含水率、发酵温度、发酵时间、菌悬液接种量等因素对产淀粉酶效果的影响,并采用正交实验对发酵条件进行了优化.单因子实验结果表明,黑曲霉固态发酵三七渣产淀粉酶适宜的硫酸铵添加量为40~60 mg/g(以干药渣计),最佳三七渣粒径为100目,最适固体培养基含水率为55%,最佳发酵温度为34℃,最适发酵时间为7d,最佳菌悬液接种量为10%(质量分数).正交实验多重比较的结果表明,优化的发酵条件为:硫酸铵添加量50 mg/g,发酵温度34℃,发酵时间5d,在此发酵条件下,黑曲霉固态发酵三七渣产生的淀粉酶的酶活可达84.15 U/g(以湿物料计).%The solid-state fermentation of notoginseng residues by Aspergillus niger was performed to investigate the effect of fermentation condition such as ammonia sulfate dosage,particle size of notoginseng residues,water content of solid medium,incubation time and temperature and inoculation size of bacteria suspension on amylase production.The single factor experiments showed that feasible fermentation conditions for amylase production were ammonia sulfate dosage of 40-60 mg/g (counted dry drug residue),raw material sieved to 100 mesh,initial water content of solid medium 55%,fermentation temperature 34 ℃,fermentation time 7 d and inoculation size 10%.The fermentation conditions were optimized by orthogonal test.They were ammonia sulfate 50 mg/g and fermentation at 34 ℃ for 5 d,under these conditions,the enzyme activity of amylase produced by drug residue fermentation could reached to 84.15 U/g (counted by wet material).

  15. Genetics of amyloglucosidase production in Aspergillus niger and Aspergillus awamori

    International Nuclear Information System (INIS)

    The results obtained with the isolation and characterization of mutants induced by irradiating 5-8 days old spores with ultraviolet light are presented. The modification in the amyloglucosidase accumulation, the allelic interactions of these mutations and the inhibitory effects of glycerol are reported. (M.A.C.)

  16. 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.

  17. 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...

  18. 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...

  19. The Aspergillus niger D-xylulose kinase gene is co-expressed with genes encoding arabinan degrading enzymes, and is essential for growth on D-xylose and L-arabinose

    NARCIS (Netherlands)

    Kuyck, van P.A.; Groot, de M.J.L.; Ruijter, G.J.G.; Vries, de R.P.; Visser, J.

    2001-01-01

    The Aspergillus nigerd-xylulose kinase encoding gene has been cloned by complementation of a strain deficient in d-xylulose kinase activity. Expression of xkiA was observed in the presence of l-arabinose, l-arabitol and d-xylose. Expression of xkiA is not mediated by XLNR, the xylose-dependent posit

  20. Solid-state Fermentation Parameters Optimization and Nutritional Improvement of Sweet Potato Residue with Aspergillus niger%黑曲霉固态发酵甘薯渣条件优化及发酵对甘薯渣营养品质的影响

    Institute of Scientific and Technical Information of China (English)

    赵华; 王雪涛; 汤加勇; 汤小朋; 贾刚; 刘光芒; 陈小玲; 王康宁

    2015-01-01

    【目的】研究黑曲霉固态发酵对甘薯渣营养价值的影响,并探讨其最佳发酵工艺参数。【方法】采用单因素试验设计,对黑曲霉3.287固态发酵甘薯渣的发酵参数如接种量、发酵时间、料水比和温度等进行优化,在此基础上,进一步采用正交试验设计,筛选出最佳发酵工艺参数,考察在最佳发酵参数条件下黑曲霉固态发酵对甘薯渣营养品质的影响。【结果】结果表明:①每克发酵原料接种黑曲霉孢子1×106个,发酵时间4 d,料水比1∶1.3,发酵温度38℃条件下发酵效果最好。②在黑曲霉优化参数下发酵,以干物质为基础,粗蛋白含量从6.37%提高到9.14%;粗脂肪从2.71%提高到4.75%;发酵后还原糖含量达到从4.42%提高到7.34%,羧甲基纤维素酶活、滤纸酶活、β-葡萄糖苷酶活和淀粉酶活分别为:3.12、2.45、2.13和3.02 U。【结论】农副产品甘薯渣经过黑曲霉固态发酵可以有效改善其营养品质。%[Objective]This experiment was conducted to investigate the nutritional improvement of sweet potato residue by solid-state fermentation (SSF)using Aspergillus niger and the optimal fermentation parameters were investigated.[Method]Single factor experiment design was adopt-ed to investigate the effects of inoculation size,fermentation time,moisture and temperature on nutritional improvement of sweet potato residue and a orthogonal experiment design was further used to optimize the fermentation parameters described above.[Results]The results showed as following:① Inoculated 1 × 10 6 germ per gram fermentation materials with Aspergillus niger strain 3.287,controlled the ratio of substrate vs water ratio to 1∶1.3 and fermented at 38 ℃ for 4 days get a best nutritional improvement of sweet potato residue.② Fermented sweet potato res-idue under the optimized condition described above and calculated base on dry

  1. 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...

  2. 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

  3. 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...

  4. Aspergillus acidus from Puerh tea and black tea does not produce ochratoxin A and fumonisin B-2

    DEFF Research Database (Denmark)

    Mogensen, Jesper Mølgaard; Varga, J.; Thrane, Ulf;

    2009-01-01

    Puerh tea is a unique Chinese fermented tea. Unlike other teas it is stored for a long period of time. Aspergillus niger is claimed to be the dominant microorganism in the Puerh tea manufacturing process and also to be common on tea in general. A. niger sensu stricto is known to produce the...

  5. Metabolic control analysis of xylose catabolism in Aspergillus

    DEFF Research Database (Denmark)

    Prathumpai, Wai; Gabelgaard, J.B.; Wanchanthuek, P.;

    2003-01-01

    dogma specifying that flux control often resides at the step following an intermediate present at high concentrations was, therefore, shown not to hold. The intracellular xylitol concentration was measured in batch cultivations of two different strains of Aspergillus niger and two different strains of...

  6. 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...

  7. Niger - Threshold (IMAGINE)

    Data.gov (United States)

    Millenium Challenge Corporation — The IMAGINE program was designed to improve educational outcomes of girls in Niger. The Millennium Challenge Corporation (MCC) funded IMAGINE as a component of its...

  8. 二次正交旋转组合设计优化黑曲霉菌株F1降解酒石酸的条件研究%Research of degradation of tartaric acid by Aspergillus niger F1 by using the quadratic orthogonal rotational combination design

    Institute of Scientific and Technical Information of China (English)

    文连奎; 董昕; 徐璐; 路鑫

    2013-01-01

    为提高酒石酸降解率,以黑曲霉降酸菌株F1为研究对象,采用四元二次正交旋转组合设计研究黑曲霉菌株F1培养温度、孢子悬浮液接种量、培养基装液量及酒石酸浓度4个因素对酒石酸降解率的影响,用Design Expert 7.1软件分析得出4个因素的回归方程.结果表明,黑曲霉降酸菌株F1对酒石酸的最佳降解条件为:培养温度34.7℃、接种量4.3%、装液量163mL、酒石酸浓度9.3g/L.在此条件下,其降解率可达到98.3%.%A quadratic orthogonal rotation combination design was used to explore the effects of incubation temperature,inoculation amount of spore suspension,medium volume,tartaric acid concentration of Aspergillus niger F1 on degradation rate of tartaric acid.A regression equation was established using Design Expert 7.1 software.The optimum tartaric acid-degrading conditions were incubation temperature of 34.7℃,inoculation amount of 4.3%,medium volume 163mL,tartaric acid concentration 9.3g/LUnder such conditions,its degradation rate was 98.3%.

  9. 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.

  10. ВЫДЕЛЕНИЕ И ОЧИСТКА ПОЛИГАЛАКТУРОНАЗ ASPERGILLUS NIGER И PENICILLIUM DIERCKXII

    OpenAIRE

    Шубаков, А.; Донцов, А.; Челпанова, Т.; Елькина, Е.

    2008-01-01

    С помощью адсорбционной хроматографии на различных носителях из культуральных жидкостей грибов Aspergillus niger и Penicillium dierckxii выделены и очищены полигалактуроназы с удельной активностью 262,6 и 63,6 ед./мг белка соответственно. Методом электрофореза в полиакриламидном геле в культуральной жидкости P. dierckxii обнаружены две изоформы фермента, из которых только одна сохраняется в конечном очищенном препарате полигалактуроназы....

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

    Directory of Open Access Journals (Sweden)

    Jorge Enrique Madrigal-Arias

    2015-09-01

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

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

    Science.gov (United States)

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

    2015-01-01

    In an effort to develop alternate techniques to recover metals from waste electrical and electronic equipment (WEEE), this research evaluated the bioleaching efficiency of gold (Au), copper (Cu) and nickel (Ni) by two strains of Aspergillus niger in the presence of gold-plated finger integrated circuits found in computer motherboards (GFICMs) and cellular phone printed circuit boards (PCBs). These three metals were analyzed for their commercial value and their diverse applications in the industry. Au-bioleaching ranged from 42 to 1% for Aspergillus niger strain MXPE6; with the combination of Aspergillus niger MXPE6 + Aspergillus niger MX7, the Au-bioleaching was 87 and 28% for PCBs and GFICMs, respectively. In contrast, the bioleaching of Cu by Aspergillus niger MXPE6 was 24 and 5%; using the combination of both strains, the values were 0.2 and 29% for PCBs and GFICMs, respectively. Fungal Ni-leaching was only found for PCBs, but with no significant differences among treatments. Improvement of the metal recovery efficiency by means of fungal metabolism is also discussed. PMID:26413051

  13. 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...

  14. The Imouraren deposit, Niger

    International Nuclear Information System (INIS)

    Imouraren deposit has been discovered in the late sixties. It is located South of Arlit where two mines are mined, one open pit and one underground. The grades of reduced Imouraren Uranium ore are lesser than these of Arlit and Akouta. Imouraren deposit is owned by COGEMA (France): 70% and ONAREM (Niger): 30%. The concession area is about 45 square kilometers. The thickness of the deposit is between 50 and 60 meters and its depth reaches 110 to 170 meters. (author)

  15. 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...

  16. 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...

  17. Growth and production of amylotic enzymes by aspergillus spp

    OpenAIRE

    Murphy, Mary B.

    1987-01-01

    The growth and production of ©¿-amylase and amyloglucosidase by Aspergillus awamori NRRL 3112 and A. niger CBS 26265 were investigated, with a view to obtaining optimal levels of both these enzymes in shake flask culture, and subsequently on the large scale. The effect of various parameters, such as carbon source, nitrogen source, presence/absence of buffering agents, carbon:nitrogen ratio , pH values, and time were examined. Following the screening of ten strains of As...

  18. Niger experience in model project

    International Nuclear Information System (INIS)

    As a uranium-producing country Niger needs a strong radiation protection infrastructure. Strategy, regulations, control of occupational and medical exposure, environmental monitoring, and waste management issues were addressed in the scope of the IAEA Model Project. The associated training, scientific visits, coordination meetings, and expert visits have yielded substantial benefits to the people of Niger. (author)

  19. Productive mutants of niger

    International Nuclear Information System (INIS)

    Seeds of six niger (Guizotia abyssinica Cass.) varieties ('GA-10', 'ONS-8', 'IGP-72', 'N-71', 'NB-9' and 'UN-4') were treated with 0.5, 0.75 and 1% ethyl methanesulphonate. After four generations of selection, 29 mutant lines were developed and those were evaluated from 1990-92 during Kharif (July to October) and Rabi (December to March) seasons. Average plant characteristics and yield data of four high yielding mutants along with 'IGP-76' (National Check), GA-10 (Zonal Check) and 'Semiliguda Local' (Local Check) are presented

  20. Areva in Niger

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-02-01

    Niger is the second poorest country in the world but it has natural resources underground in the form of uranium ores deposits. This uranium is currently mined by two companies incorporated under Nigerian law: Somair and Cominak, operated by the principal shareholder Areva (through its subsidiary Cogema). After a presentation of Somair and Cominak key figures, this document details the working conditions and radiological protection, the environmentally friendly operations, the production traceability, the local economic development, the strengthening of the health care system and the development of the infrastructure. (A.L.B.)