Initial studies on the influence of Aspergillus niger on the wood components of Populus sp.

2020 ◽  
Vol 110 ◽  
pp. 140-147
Author(s):  
Ewa Lisiecka ◽  
Anna Lesiak ◽  
Jan Szadkowski ◽  
Dominika Szadkowska ◽  
Andrzej Radomski ◽  
...  
Keyword(s):  
Aspergillus Niger ◽  
Growth Conditions ◽  
Wood Chips ◽  
Spore Suspension ◽  
Sodium Chlorite ◽  
Poplar Wood ◽  
Chemical Analyses ◽  
Structural Components ◽  
Wood Degradation ◽  
Degree Of Degradation

Initial studies on the influence of Aspergillus niger on the wood components of Populus sp. An attempt was made to determine the content of structural substances (cellulose, holocellulose, lignin) and non-structural substances in poplar wood (Populus sp.) infected with the mentioned fungus. For this purpose, wood chips were infected with spore suspension and then incubated under sterile and suitable growth conditions. After 7, 14 and 21 days the degree of poplar wood degradation was assessed by determining the substances contained in the wood by performing chemical analyses: Kürschner-Hoffer cellulose, holocellulose by the sodium chlorite method, lignin in accordance with PN-92/P50092 standard and non-structural components. The conducted analyses made it possible to determine the effect of Aspergillus niger’s presence time on the degree of degradation of individual wood components.

scholarly journals Improvement of Enzymatic Saccharification of Cellulose-Containing Raw Materials Using Aspergillus niger

Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1360
Author(s):  
Ekaterina Budenkova ◽  
Stanislav Sukhikh ◽  
Svetlana Ivanova ◽  
Olga Babich ◽  
Vyacheslav Dolganyuk ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Aspergillus Niger ◽  
Filter Paper ◽  
Raw Materials ◽  
Enzymatic Saccharification ◽  
Wood Chip ◽  
Cellulase Activity ◽  
Wood Chips ◽  
Acid Pretreatment ◽  
Hydrolysis Of

Enzymatic hydrolysis of cellulose-containing raw materials, using Aspergillus niger, were studied. Filter paper, secondary cellulose-containing or starch-containing raw materials, miscanthus cellulose after alkaline or acid pretreatment, and wood chip cellulose, were used as substrates. The study focused on a wild A. niger strain, treated, or not (control), by ultraviolet (UV) irradiations for 45, 60, or 120 min (UV45, UV60, or UV120), or by UV irradiation for 120 min followed by a chemical treatment with NaN3 + ItBr for 30 min or 80 min (UV120 + CH30 or UV120 + CH80). A mixture of all the A. niger strains (MIX) was also tested. A citrate buffer, at 50 mM, wasthe most suitable for enzymatic hydrolysis. As the UV exposure time increased to 2 h, the cellulase activity of the surviving culturewas increased (r = 0.706; p < 0.05). The enzymatic activities of the obtained strains, towards miscanthus cellulose, wood chips, and filter paper, were inferior to those obtained with commercial enzymes (8.6 versus 9.1 IU), in some cases. Under stationary hydrolysis at 37 °C, pH = 4.7, the enzymatic activity of A. niger UV120 + CH30 was 24.9 IU. The enzymatic hydrolysis of secondary raw materials, using treated A. niger strains, was themost effective at 37 °C. Similarly, the most effective treatment of miscanthus cellulose and wood chips occurred at 50 °C. The maximum conversion of cellulose to glucose was observed using miscanthus cellulose (with alkaline pretreatment), and the minimum conversion was observed when using wood chips. The greatest value of cellulase activity was evidenced in the starch-containing raw materials, indicating that A. niger can ferment not only through cellulase activity, but also via an amylolytic one.

Formation of Cr-rich Nano-clusters and Columns in (Zn,Cr)Te Grown by MBE

2009 ◽  
Vol 1183 ◽  
Author(s):  
Yôtarõ Nishio ◽  
Kôichirô Ishikawa ◽  
Shinji Kuroda ◽  
Masanori Mitome ◽  
Yoshio Bando
Keyword(s):  
Magnetic Properties ◽  
Substrate Temperature ◽  
Crystallographic Orientation ◽  
Vertical Direction ◽  
Growth Conditions ◽  
Chemical Analyses ◽  
Mbe Growth ◽  
One Dimensional ◽  
X Ray ◽  
Cr Content

AbstractThe correlation between the Cr aggregation and magnetic properties are investigated for the series of Zn1-xCrxTe films grown by MBE with a systematic variation of growth conditions. Structural and chemical analyses using TEM and energy-dispersive X-ray spectroscopy (EDS) reveal that the crystallinity and the Cr distribution change significantly with the substrate temperature during the MBE growth. For a relatively low average Cr content x ≅ 0.05, it is found that the crystal quality is improved with the increase of the substrate temperature. For a higher average Cr content x ≅ 0.2, the shape of Cr-rich regions is transformed from isolated clusters into one-dimensional nanocolumns with the increase of the substrate temperature. The direction of the nanocolumn formation changes depending on the crystallographic orientation of the grown films. In the magnetization measurements, anisotropic magnetic properties are observed in the films in which Cr-rich nanocolumns are formed in the vertical direction, depending on the relation between the direction of the nanocolumns and the applied magnetic fields.

scholarly journals Mycotoxins in Crude Building Materials from Water-Damaged Buildings

2000 ◽  
Vol 66 (5) ◽  
pp. 1899-1904 ◽  
Author(s):  
Tapani Tuomi ◽  
Kari Reijula ◽  
Tom Johnsson ◽  
Kaisa Hemminki ◽  
Eeva-Liisa Hintikka ◽  
...  
Keyword(s):  
Building Materials ◽  
Growth Conditions ◽  
Fungal Species ◽  
Aspergillus Versicolor ◽  
Chemical Analyses ◽  
Bulk Materials ◽  
Toxigenic Fungi ◽  
Three Samples

ABSTRACT We analyzed 79 bulk samples of moldy interior finishes from Finnish buildings with moisture problems for 17 mycotoxins, as well as for fungi that could be isolated using one medium and one set of growth conditions. We found the aflatoxin precursor, sterigmatocystin, in 24% of the samples and trichothecenes in 19% of the samples. Trichothecenes found included satratoxin G or H in five samples; diacetoxyscirpenol in five samples; and 3-acetyl-deoxynivalenol, deoxynivalenol, verrucarol, or T-2-tetraol in an additional five samples. Citrinine was found in three samples. Aspergillus versicolor was present in most sterigmatocystin-containing samples, and Stachybotrys spp. were present in the samples where satratoxins were found. In many cases, however, the presence of fungi thought to produce the mycotoxins was not correlated with the presence of the expected compounds. However, when mycotoxins were found, some toxigenic fungi usually were present, even if the species originally responsible for producing the mycotoxin was not isolated. We conclude that the identification and enumeration of fungal species present in bulk materials are important to verify the severity of mold damage but that chemical analyses are necessary if the goal is to establish the presence of mycotoxins in moldy materials.

scholarly journals The AngFus3 Mitogen-Activated Protein Kinase Controls Hyphal Differentiation and Secondary Metabolism in Aspergillus niger

2015 ◽  
Vol 14 (6) ◽  
pp. 602-615 ◽  
Author(s):  
Bert-Ewald Priegnitz ◽  
Ulrike Brandt ◽  
Khomaizon A. K. Pahirulzaman ◽  
Jeroen S. Dickschat ◽  
André Fleißner
Keyword(s):  
Aspergillus Niger ◽  
Map Kinase ◽  
Secondary Metabolism ◽  
Filamentous Fungi ◽  
Cell Types ◽  
Growth Conditions ◽  
Mitogen Activated Protein Kinase ◽  
Content Type ◽  
Mitogen Activated Protein ◽  
Upstream Kinase

ABSTRACTAdaptation to a changing environment is essential for the survival and propagation of sessile organisms, such as plants or fungi. Filamentous fungi commonly respond to a worsening of their growth conditions by differentiation of asexually or sexually produced spores. The formation of these specialized cell types is, however, also triggered as part of the general life cycle by hyphal age or density. Spores typically serve for dispersal and, therefore, translocation but can also act as resting states to endure times of scarcity. Eukaryotic differentiation in response to environmental and self-derived signals is commonly mediated by three-tiered mitogen-activated protein (MAP) kinase signaling cascades. Here, we report that the MAP kinase Fus3 of the black moldAspergillus niger(AngFus3) and its upstream kinase AngSte7 control vegetative spore formation and secondary metabolism. Mutants lacking these kinases are defective in conidium induction in response to hyphal density but are fully competent in starvation-induced sporulation, indicating that conidiation inA. nigeris triggered by various independent signals. In addition, the mutants exhibit an altered profile of volatile metabolites and secrete dark pigments into the growth medium, suggesting a dysregulation of the secondary metabolism. By assigning the AngFus3 MAP kinase pathway to the transduction of a potentially self-derived trigger, this work contributes to the unraveling of the intricate signaling networks controlling fungal differentiation. Moreover, our data further support earlier observations that differentiation and secondary metabolism are tightly linked in filamentous fungi.

scholarly journals Simultaneous amyloglucosidase and exo-polygalacturonase production by Aspergillus niger using solid-state fermentation

2007 ◽  
Vol 50 (5) ◽  
pp. 759-766 ◽  
Author(s):  
Jorge Alberto Vieira Costa ◽  
Eliane Colla ◽  
Glênio Magagnin ◽  
Lucielen Oliveria dos Santos ◽  
Mauricio Vendruscolo ◽  
...  
Keyword(s):  
Solid State ◽  
Aspergillus Niger ◽  
Rice Bran ◽  
Solid State Fermentation ◽  
Culture Media ◽  
Spore Suspension ◽  
Defatted Rice Bran ◽  
Polygalacturonase Production ◽  
Different Strains ◽  
Inoculum Type

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.

Continuous weighing of a pile of poplar wood chips – A comparison of methods to determine the dry matter losses during storage

2017 ◽  
Vol 96 ◽  
pp. 119-129 ◽  
Author(s):  
Hannes Lenz ◽  
Ralf Pecenka ◽  
Christine Idler ◽  
Sabrina Dumfort ◽  
Carly Whittaker ◽  
...  
Keyword(s):  
Dry Matter ◽  
Wood Chips ◽  
Comparison Of Methods ◽  
Poplar Wood

scholarly journals Effect of growth conditions on β-glucosidase production by local isolate of Aspergillus niger using rice bran substrate

2020 ◽  
Vol 21 (9) ◽  
Author(s):  
Sri Sugiwati ◽  
Muhammad Hanafi ◽  
Hanifah Lioe ◽  
Maggy Suhartono
Keyword(s):  
Aspergillus Niger ◽  
Rice Bran ◽  
Incubation Time ◽  
Incubation Temperature ◽  
Glycosyl Hydrolase ◽  
Fermentation Medium ◽  
Growth Conditions ◽  
Mineral Salts ◽  
Local Isolate ◽  
Substrate Ratio

Abstract. Sugiwati S, Hanafi M, Lioe HN, Suhartono MT. 2020.  Effect of growth conditions on β-glucosidase production by local isolate of Aspergillus niger using rice bran substrate. Biodiversitas 21: 4058-4066. β-Glucosidase is the family of glycosyl hydrolase that have potential role in various food industry, such as in tea, wine and vanilla industries to increase the aroma and production of isoflavone aglycons in soybean flour. The present work produced β-glucosidase from local isolate of Aspergillus niger InaCC F57 under solid-state fermentation (SSF) using rice bran substrate. Fermentation process was made in various conditions with respect to carbon source as substrate, initial pH of fermentation medium, incubation time, water to substrate ratio, fermentation temperature, and addition of Mandels mineral salts solution. The results showed that activity of β-glucosidase was best at, i.e., 2.45 U/mL, with the use of rice bran as substrate. Furthermore, optimum condition for the highest production of β-glucosidase occurred at pH 2.0, incubation time of 5 days, water to substrate ratio of 1.5: 1, and incubation temperature of 32°C. Additionally, in optimum fermentation conditions, production of β-glucosidase could be enhanced up to 26.22% with the presence of Mandels mineral salts solution as compared to the control.

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