Screening of Cellulase, Pectinase and Xylanase activities and optimization of radial Mycelial growth of two Thermophilic Fungi

The enzymatic activity of Thermomyces lanuginosus BPJ-10 and Rhizomucor pusillus BPJ-2 were observed through qualitative screening programme which was demonstrated by the hydrolysis of substrate on solid media. Both the fungi exhibited potential xylanolytic and pectinolytic activities whereas no cellulase activity was observed in T. lanuginosus BPJ-10 and very low cellulase activity was found in R. pusillus BPJ- 2. The optimum temperature for mycelial growth of T. lanuginosus BPJ-10 and R. pusillus BPJ-2 were found to be 50 and 45°C, respectively, whereas the optimum pH for both of them were 6.5 and 5, respectively. Out of five culture media used, both the fungi showed maximum radial mycelia growth on Potato Dextrose Agar. DOI: http://dx.doi.org/10.3329/bjb.v42i2.18021 Bangladesh J. Bot. 42(2): 207-213, 2013 (December

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Production of Aflatoxins B and G on Solid and Broth Culture Media

Journal of Food Protection ◽

10.4315/0362-028x-40.12.828 ◽

1977 ◽

Vol 40 (12) ◽

pp. 828-830 ◽

Cited By ~ 3

Author(s):

A. J. DELUCCA ◽

R. Y. MAYNE ◽

A. O. FRANZ ◽

R. L. ORY

Keyword(s):

Mycelial Growth ◽

Aspergillus Parasiticus ◽

Culture Media ◽

Aflatoxin Production ◽

The Other ◽

Broth Culture ◽

Solid Media

Mycelial growth and production of aflatoxins by Aspergillus parasiticus NRRL A-16,462, on whole peanuts, undelintered cottonseed, and shredded wheat was compared to growth and aflatoxin production on 10% broths of the same substrates. The greatest amount of toxins was produced on shredded wheat as a whole substrate. The least amount was produced in shredded wheat broth medium. Intermediate levels of toxin were produced on cottonseed in both types of media. More aflatoxin was produced on peanut broth than on whole peanuts. Mycelial growth on whole shredded wheat was greater than growth on the other solid media though it had the lowest amount of growth of the three broth media. Among whole substrates, growth on fuzzy cottonseed was least but mycelial growth on cottonseed broth was second of the three broth media. Growth on whole peanuts was as great as on shredded wheat; on peanut broth, it was the greatest of the three broth media. On whole substrates, the ratio of aflatoxins B:G produced was highest on shredded wheat and lowest on peanuts. In broth culture the B:G ratio was largest on the cottonseed and lowest on shredded wheat.

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

Processes ◽

10.3390/pr9081360 ◽

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.

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Chain extension of ribonucleic acid by enzymes from rat liver cytoplasm

Biochemical Journal ◽

10.1042/bj1090485 ◽

1968 ◽

Vol 109 (4) ◽

pp. 485-494 ◽

Cited By ~ 24

Author(s):

N. M. Wilkie ◽

R. M. S. Smellie

Keyword(s):

Rat Liver ◽

Alkaline Hydrolysis ◽

Actinomycin D ◽

Chain Extension ◽

Supernatant Fraction ◽

Inorganic Pyrophosphate ◽

Optimum Ph ◽

Microsome Fraction ◽

Hydrolysis Of ◽

Generating System

1. The 105000g supernatant fraction of rat liver catalyses the incorporation of ribonucleotides from ribonucleoside triphosphates into polyribonucleotide material. The reaction requires Mg2+ ions and is enhanced by the addition of an ATP-generating system and RNA, ATP, UTP and CTP but not GTP are utilized in this reaction. In the case of UTP, the product is predominantly a homopolymer containing 2–3 uridine residues, and there is evidence that these may be added to the 3′-hydroxyl ends of RNA or oligoribonucleotide primers. 2. The microsome fraction of rat liver incorporates ribonucleotides from ATP, GTP, CTP and UTP into polyribonucleotide material. This reaction requires Mg2+ ions and is enhanced slightly by the addition of an ATP-generating system, and by RNA but not DNA. Supplementation of the reaction mixture with the three complementary ribonucleoside 5′-triphosphates greatly increases the utilization of a single labelled ribonucleoside 5′-triphosphate. The optimum pH is in the range 7·0–8·5, and the reaction is strongly inhibited by inorganic pyrophosphate and to a much smaller degree by inorganic orthophosphate. It is not inhibited by actinomycin D or by deoxyribonuclease. In experiments with [32P]UTP in the absence of ATP, GTP and CTP, 80–90% of 32P was recovered in UMP-2′ or −3′ after alkaline hydrolysis of the reaction product. When the reaction mixture was supplemented with ATP, GTP and CTP, however, about 40% of the 32P was recovered in nucleotides other than UMP-2′ or −3′. Although the reactions seem to lead predominantly to the synthesis of homopolymers, the possibility of some formation of some heteropolymer is not completely excluded.

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CHOLESTEROL ESTER HYDROLYSIS BY HOMOGENATES OF WHOLE TESTIS, SEMINIFEROUS TUBULES AND INTERSTITIAL CELLS OF MATURE RATS

Journal of Endocrinology ◽

10.1677/joe.0.0750235 ◽

1977 ◽

Vol 75 (2) ◽

pp. 235-243 ◽

Cited By ~ 2

Author(s):

J. P. RENSTON ◽

T. J. IHRIG ◽

R. H. RENSTON ◽

B. GONDOS ◽

R. J. MORIN

Keyword(s):

Cholesterol Ester ◽

Incubation Temperature ◽

Hydrolytic Activity ◽

Interstitial Cells ◽

Seminiferous Tubules ◽

Cholesterol Ester Hydrolase ◽

Ester Hydrolase ◽

Optimum Ph ◽

Hormone Biosynthesis ◽

Hydrolysis Of

The characteristics and localization of a cholesterol ester hydrolase enzyme in homogenates of whole testis and in isolated seminiferous tubules and interstitial cells of mature rats have been investigated. Hydrolysis of cholesteryl [1-14C]oleate occurred at an optimum pH of 7·0 was linearly related to time up to 5–6 h of incubation and increased linearly up to 0·25 mg protein/incubation. Hydrolytic activity was inhibited by increasing the incubation temperature from 29 to 41 °C and by sonication. Cholesterol ester hydrolase activity/mg protein was three times greater in homogenates of seminiferous tubules than in interstitial cells. Cholesterol ester hydrolase may function to provide precursors for use in seminiferous tubular steroid hormone biosynthesis or germ cell maturation.

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Growth and sporulation of Metarhizium flavoviride var. Flavoviride on culture media and lighting regimes

Scientia Agricola ◽

10.1590/s0103-90162001000300026 ◽

2001 ◽

Vol 58 (3) ◽

pp. 613-616 ◽

Cited By ~ 6

Author(s):

Sideney Becker Onofre ◽

Cindia Mara Miniuk ◽

Neiva Monteiro de Barros ◽

João Lúcio Azevedo

Keyword(s):

Biological Control ◽

Mycelial Growth ◽

Culture Media ◽

Agar Medium ◽

Potato Dextrose Agar ◽

Continuous Illumination ◽

Agricultural Pests ◽

Dark Cycle ◽

Metarhizium Flavoviride ◽

Conidia Production

Entomopathogenic fungi from the genus Metarhizium are largely used for the biological control of agricultural pests by conidia spreading on the field. Although conidia production is well studied in M. anisopliae, only few research studies were done in M. flavoviride. The present work was carried out alming to evaluate the Mycelial growth and sporulation of the entomopathogenic fungus Metarhizium flavoviride var. flavoviride growing at 27 ± 2°C on Potato-dextrose-agar (PDA), Czapek-agar (CZP) and a complete agar medium (CM) under three lighting regimes, (continuous illumination, light/dark cycle and an black light/dark cycle) were investigated. A completely randomized 3 × 3 (culture media × lighting regime) factorial design with four replicates was used. The best mycelial growth and sporulation occurred on the PDA and CM media under continuous illumination (P <= 0,05).

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Production of Thermostable Lipase by Thermomyces lanuginosus on Solid-State Fermentation: Selective Hydrolysis of Sardine Oil

Applied Biochemistry and Biotechnology ◽

10.1007/s12010-014-1159-9 ◽

2014 ◽

Vol 174 (5) ◽

pp. 1859-1872 ◽

Cited By ~ 12

Author(s):

Nayeli Ávila-Cisneros ◽

Susana Velasco-Lozano ◽

Sergio Huerta-Ochoa ◽

Jesús Córdova-López ◽

Miquel Gimeno ◽

...

Keyword(s):

Solid State ◽

Solid State Fermentation ◽

Thermomyces Lanuginosus ◽

Selective Hydrolysis ◽

Thermostable Lipase ◽

Sardine Oil ◽

Hydrolysis Of

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Properties of a new fungal b-galactosidase with potential application in the dairy industry

Revista de Microbiologia ◽

10.1590/s0001-37141999000300014 ◽

1999 ◽

Vol 30 (3) ◽

pp. 265-271 ◽

Cited By ~ 5

Author(s):

Rubens Cruz ◽

Vinícius D'Arcádia Cruz ◽

Juliana Gisele Belote ◽

Marcelo de Oliveira Khenayfes ◽

Claudia Dorta ◽

...

Keyword(s):

Hydrolytic Activity ◽

Industrial Applications ◽

Transferase Activity ◽

Optimum Temperature ◽

Milk Whey ◽

Beneficial Effects ◽

Optimum Ph ◽

Semi Solid ◽

Good Productivity ◽

Hydrolysis Of

b-Galactosidase or b-D-galactoside-galactohydrolase (EC. 3.2.1.23) is an important enzyme industrially used for the hydrolysis of lactose from milk and milk whey for several applications. Lately, the importance of this enzyme was enhanced by its galactosyltransferase activity, which is responsible for the synthesis of transgalactosylated oligosaccharides (TOS) that act as functional foods, with several beneficial effects on consumers. Penicillium simplicissimum, a strain isolated from soil, when grown in semi-solid medium showed good productivity of b-galactosidase with galactosyltransferase activity. The optimum pH for hydrolysis was in the 4.04.6 range and the optimum pH for galactosyltransferase activity was in the 6.07.0 range. The optimum temperature for hydrolysis and transferase activity was 55-60°C and 50°C, respectively, and the enzyme showed high thermostability for the hydrolytic activity. The enzyme showed a potential for several industrial applications such as removal of 67% of the lactose from milk and 84% of the lactose from milk whey when incubated at their original pH (4.5 and 6.34, respectively) under optimum temperature conditions. When incubated with a 40% lactose solution in 150 mM McIlvaine buffer, pH 4.5, at 55°C the enzyme converted 86.5% of the lactose to its component monosaccharides. When incubated with a 60% lactose solution in the same buffer but at pH 6.5 and 50°C, the enzyme can synthetize up to 30.5% TOS, with 39.5% lactose and 30% monosaccharides remaining in the preparation.

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Fungicidal effect of silver nanoparticles on toxigenic fungi in cocoa

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x2016001200003 ◽

2016 ◽

Vol 51 (12) ◽

pp. 1929-1936 ◽

Cited By ~ 17

Author(s):

Raquel Villamizar-Gallardo ◽

Johann Faccelo Osma Cruz ◽

Oscar Orlando Ortíz-Rodriguez

Keyword(s):

Silver Nanoparticles ◽

Fusarium Solani ◽

Theobroma Cacao ◽

Mycelial Growth ◽

Culture Media ◽

Fungal Growth ◽

Inhibitory Effect ◽

Plant Tissues ◽

Inhibition Effect ◽

Toxigenic Fungi

Abstract: The objective of this work was to evaluate the microbicidal effect of silver nanoparticles (AgNPs) on potentially toxigenic fungi affecting cocoa (Theobroma cacao) crops. These fungi, isolated from diseased cocoa pods, were characterized phenotypically and genotypically. The microbicidal effect was assessed by measuring radial mycelial growth, in synthetic culture media, and at different AgNP concentrations in plant tissues. The inhibition effect was monitored in Petri dishes, and changes in fungal structures were observed through scanning electron microscopy. Two potentially toxigenic fungi were highly prevalent: Aspergillus flavus and Fusarium solani. The inhibition assays, performed in liquid and solid synthetic culture media, showed that AgNPs did not significantly affect the growth of these fungi, even at the highest concentration (100 ppm). By contrast, they showed a positive inhibitory effect in plant tissues, especially in the cortex, when infected with A. flavus, in which an 80 ppm dose completely inhibited fungal growth. However, once fungi have managed to penetrate inside the pods, their growth is unavoidable, and AgNP effect is reduced. On F. solani, the studied nanomaterial only induced some texture and pigmentation changes. The microbicidal effect of chemically synthesized silver nanoparticles is greater in plant tissues than in culture media.

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Selection of filamentous fungi that are resistant to the herbicides atrazine, glyphosate and pendimethalin

Acta Scientiarum Agronomy ◽

10.4025/actasciagron.v43i1.51656 ◽

2021 ◽

Vol 43 ◽

pp. e51656

Author(s):

Nara Priscila Barbosa Bravim ◽

Anatércia Ferreira Alves ◽

José Fábio França Orlanda ◽

Patricia Barbosa Rodrigues Silva

Keyword(s):

Filamentous Fungi ◽

Mycelial Growth ◽

Culture Medium ◽

Agricultural Soils ◽

Culture Media ◽

Fusarium Verticillioides ◽

Fungal Growth ◽

Relative Growth ◽

Maximum Inhibition ◽

Selection Of

The objective of the present study was to isolate fungi from agricultural soils and evaluate fungal growth in culture medium contaminated with atrazine, glyphosate and pendimethalin. Filamentous fungi were isolated from agricultural soils and cultured in a modified culture medium containing 0, 10, 20, 50, and 100 μg mL-1 atrazine, glyphosate and pendimethalin for 14 days at 28°C. The fungi that presented optimal and satisfactory growth were plated in Sabouraud culture medium with 4% dextrose and containing the herbicides at concentrations of 0, 10, 20, 50, and 100 μg mL-1 for seven days at 28°C. The mean mycelial growth values were submitted to analysis of variance and the Tukey test (p < 0.05%) for comparison and relative growth determination, and maximum inhibition rates were calculated. The isolated fungi Aspergillus fumigatus, Fusarium verticillioides and Penicillium citrinum were shown to be resistant to atrazine, glyphosate and pendimethalin. F. verticillioides showed higher mean mycelial growth in the culture media contaminated with atrazine and glyphosate than the other two fungi. In the culture medium contaminated with pendimethalin, F. verticillioides, and A. fumigatus presented the highest mean mycelial growth values.

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