Conversion of viridin to viridiol by viridin-producing fungi

1987 ◽  
Vol 33 (11) ◽  
pp. 963-966 ◽  
Author(s):  
Richard W. Jones ◽  
Joseph G. Hancock
Keyword(s):  
Carbon Source ◽  
Nitrogen Source ◽  
Production System ◽  
Liquid Culture ◽  
Calcium Nitrate ◽  
Peat Moss ◽  
Significant Extent ◽  
Gliocladium Virens ◽  
Culture Conversion ◽  
Simple Production

The fungistatic compound viridin, produced by the fungus Gliocladium virens, was found to be irreversibly reduced to the phytotoxin viridiol in liquid culture. Conversion occurred only in the presence of viridin-producing fungi and was subsequent to viridin production. Radiolabelled viridin was rapidly taken up by the mycelium of G. virens and reduced to radiolabelled viridiol, while labelled viridiol was not taken up to any significant extent by the mycelium. Reduction of viridin to viridiol was independent of culture pH, carbon source, and nitrogen source or quantity. A simple production system consisting of peat moss amended with dextrose and calcium nitrate and inoculated with G. virens supported production of 86 μg viridiol/g peat. This production system, when applied to soil, may have value as a herbicide.

Cell growth and pigment production in suspension cultures of a mycobiont isolated from the lichen Cladonia cristaiella

1995 ◽  
Vol 73 (S1) ◽  
pp. 590-594 ◽  
Author(s):  
Y. Yamamoto ◽  
Y. Kinoshita ◽  
T. Kurokawa ◽  
I. Yoshimura ◽  
V. Ahmadjian ◽  
...  
Keyword(s):  
Cell Growth ◽  
Carbon Source ◽  
Nitrogen Source ◽  
Liquid Culture ◽  
Pigment Production ◽  
Malt Extract ◽  
Nutritional Factors ◽  
Cultural Conditions ◽  
Acetone Extracts ◽  
Affect Cell Growth

This is the first study on the factors that affect cell growth and the production of secondary metabolites of a lichen mycobiont in liquid culture. An ascospore-derived strain of Cladonia cristatella mycobiont accumulated and excreted red pigments into a liquid medium. Growth of the mycobiont was increased by using liquid Lilly–Barnett medium containing 16% (w/v) sucrose as a carbon source, 0.2% (w/v) L-glutamine as a nitrogen source, and 0.2% (w/v) polypeptone, adjusting pH to 5.0 before autoclaving, and incubating cultures at 20 °C. Pigment production by the mycobiont was increased by using liquid Lilly–Barnett medium containing 4% (w/v) sucrose as a carbon source, 0.2% (w/v) L-asparagine as a nitrogen source, and 0.2% (w/v) malt extract, adjusting pH to 5.0 before autoclaving and incubating cultures at 20 °C. All acetone extracts under any cultural conditions yielded similar HPLC chromatograms. We proved no relationship between cell growth and secondary metabolism based on the nutritional factors in the cultured C. cristatella mycobiont. Key words: lichen, suspension culture, Cladonia cristatella mycobiont, red pigment, production, and growth factor.

Studies on the Biological Characteristics of Termitomyces Albuminosus Hypha

2013 ◽  
Vol 709 ◽  
pp. 810-813 ◽  
Author(s):  
Xiong Ya ◽  
Min Jie Li
Keyword(s):  
Growth Factors ◽  
Carbon Source ◽  
Nitrogen Source ◽  
Biological Characteristics ◽  
Edible Fungi ◽  
Growth Environment ◽  
Wild Edible Fungi ◽  
Development And Utilization

Termitomyces albuminosus is a kind of local distinctive wild edible fungi in southwest of China. It is delicious, rich in nutrition and has high development and utilization value, but owing to the restrictions of growth environment, it can not be cultivated artificially. This article mainly studied on the biological characteristics of Termitomyces albuminosus Hypha, and found out the optimal carbon source, nitrogen source, growth factors and the C/N ratio that are suitable for the growth of Hypha of Termitomyces albuminosus .

Development of mutants of Gliocladium virens tolerant to benomyl

1990 ◽  
Vol 36 (7) ◽  
pp. 484-489 ◽  
Author(s):  
G. C. Papavizas ◽  
D. P. Roberts ◽  
K. K. Kim
Keyword(s):  
Carbon Source ◽  
Type Strain ◽  
Wild Type Strain ◽  
Carbon Sources ◽  
Sclerotium Rolfsii ◽  
Wild Type ◽  
Gliocladium Virens ◽  
Rhizosphere Competence ◽  
Filter Paper Cellulase ◽  
Type Strains

Aqueous suspensions of conidia of Gliocladium virens strains Gl-3 and Gl-21 were exposed to both ultraviolet radiation and ethyl methanesulfonate. Two mutants of Gl-3 and three of Gl-21 were selected for tolerance to benomyl at 10 μg∙mL−1, as indicated by growth and conidial germination on benomyl-amended potato dextrose agar. The mutants differed considerably from their respective wild-type strains in appearance, growth habit, sporulation, carbon-source utilization, and enzyme activity profiles. Of 10 carbon sources tested, cellobiose, xylose, and xylan were the best for growth, galactose and glucose were intermediate, and arabinose, ribose, and rhamnose were poor sources of carbon. The wild-type strains and the mutants did not utilize cellulose as the sole carbon source for growth. Two benomyl-tolerant mutants of Gl-3 produced less cellulase (β-1,4-glucosidase, carboxymethylcellulase, filter-paper cellulase) than Gl-3. In contrast, mutants of Gl-21 produced more cellulase than the wild-type strain. Only Gl-3 provided control of blight on snapbean caused by Sclerotium rolfsii. Wild-type strain Gl-21 and all mutants from both strains were ineffective biocontrol agents. Key words: Gliocladium, benomyl tolerance, Sclerotium, rhizosphere competence.

scholarly journals Monomethylamine as a Nitrogen Source for a Nonmethylotrophic Bacterium, Agrobacterium tumefaciens

2010 ◽  
Vol 76 (12) ◽  
pp. 4102-4104 ◽  
Author(s):  
Yin Chen ◽  
Kathryn L. McAleer ◽  
J. Colin Murrell
Keyword(s):  
Agrobacterium Tumefaciens ◽  
Carbon Source ◽  
Nitrogen Source ◽  
Sole Nitrogen Source ◽  
Key Enzymes ◽  
Genes Encoding

ABSTRACT Monomethylamine can be used by nonmethylotrophs as a sole nitrogen source but not as a carbon source; however, little is known about the genes and enzymes involved. The γ-glutamylmethylamide/N-methylglutamate pathway for monomethylamine utilization by methylotrophs has recently been resolved. We have identified genes encoding key enzymes of this pathway in nonmethylotrophs (e.g., Agrobacterium tumefaciens) and demonstrated that this pathway is also involved in the utilization of monomethylamine as a nitrogen source by nonmethylotrophs.

scholarly journals Mutants affecting histidine utilization inAspergillus nidulans

1975 ◽  
Vol 25 (2) ◽  
pp. 119-135 ◽  
Author(s):  
Meryl Polkinghorne ◽  
M. J. Hynes
Keyword(s):  
Carbon Source ◽  
Nitrogen Source ◽  
Sole Carbon Source ◽  
Nitrogen Sources ◽  
Limiting Factor ◽  
Sole Nitrogen Source ◽  
Wild Type ◽  
Exogenous Substrate ◽  
Growth Properties ◽  
Type Strains

SUMMARYWild-type strains ofAspergillus nidulansgrow poorly onL-histidine as a sole nitrogen source. The synthesis of the enzyme histidase (EC. 4.3.1.3) appears to be a limiting factor in the growth of the wild type, as strains carrying the mutantareA102 allele have elevated histidase levels and grow strongly on histidine as a sole nitrogen source.L-Histidine is an extremely weak sole carbon source for all strains.Ammonium repression has an important role in the regulation of histidase synthesis and the relief of ammonium repression is dependent on the availability of a good carbon source. The level of histidase synthesis does not respond to the addition of exogenous substrate.Mutants carrying lesions in thesarA orsarB loci (suppressor ofareA102) have been isolated. The growth properties of these mutants on histidine as a sole nitrogen source correlate with the levels of histidase synthesized. Mutation at thesarA andsarB loci also reduces the utilization of a number of other nitrogen sources. The data suggest that these two genes may code for regulatory products involved in nitrogen catabolism. No histidase structural gene mutants were identified and possible explanations of this are discussed.

scholarly journals Production of Feruloyl Esterase from Aspergillus niger by Solid-State Fermentation on Different Carbon Sources

2011 ◽  
Vol 2011 ◽  
pp. 1-4 ◽  
Author(s):  
Shiyi Ou ◽  
Jing Zhang ◽  
Yong Wang ◽  
Ning Zhang
Keyword(s):  
Carbon Source ◽  
Nitrogen Source ◽  
Wheat Bran ◽  
Cell Walls ◽  
Carbon Sources ◽  
Feruloyl Esterase ◽  
Plant Cell Walls ◽  
Optimal Conditions ◽  
Carbon And Nitrogen ◽  
Maize Bran

A mixture of wheat bran with maize bran as a carbon source and addition of (NH4)SO4 as nitrogen source was found to significantly increase production of feruloyl esterase (FAE) enzyme compared with wheat bran as a sole carbon and nitrogen source. The optimal conditions in conical flasks were carbon source (30 g) to water 1 : 1, maize bran to wheat bran 1 : 2, (NH4)SO4 1.2 g and MgSO4 70 mg. Under these conditions, FAE activity was 7.68 mU/g. The FAE activity on the mixed carbon sources showed, high activity against the plant cell walls contained in the cultures.

Plant Growth Response to the Phytotoxin Viridiol Produced by the FungusGliocladium virens

Weed Science ◽  
1988 ◽  
Vol 36 (5) ◽  
pp. 683-687 ◽  
Author(s):  
Richard W. Jones ◽  
W. Thomas Lanini ◽  
Joseph G. Hancock
Keyword(s):  
Root Zone ◽  
Wide Spectrum ◽  
Soil Surface ◽  
Application Rate ◽  
Herbicidal Activity ◽  
Peat Moss ◽  
Application Rates ◽  
Gliocladium Virens ◽  
Root Necrosis ◽  
Shoot Weight

Gliocladium virens, when grown on peat moss amended with sucrose and ammonium nitrate and then applied to soil, resulted in root necrosis. Herbicidal activity was correlated with fungal production of the phytotoxin viridiol. Viridiol had a wide spectrum of activity; it was particularly effective against annual composite species but was less effective in monocot control. Emergence of most weeds was reduced >90% at application rates of 8.7% (of total volume) or less. Treated seedling dry weights were drastically reduced. Applications of 4.5% reduced root and shoot weight of redroot pigweed by 93 and 98%, respectively. Crops were affected at higher treatment levels; however, the toxicity was readily avoided by applying the mycoherbicide out of the root zone of the crop, instead applying it between the seed and the soil surface. Viridiol production, which confers herbicidal activity, was detected 3 days after incorporation of the fungus-peat mixture. Viridiol production peaked on days 5 and 6 at approximately 25 μg viridiol/100 ml soil, based upon an application rate of 11%, then declined to undetectable levels by the end of 2 weeks.

scholarly journals KAJIAN PENGARUH PENINGKATAN KONSENTRASI EKSTRAK KHAMIR PADA MEDIA HESTRIN DAN SCHRAMM TERHADAP PEROLEHAN SELULOSA OLEH Acetobacter liquefaciens SRC-4

2014 ◽  
Vol 5 (2) ◽  
Author(s):  
Ermina Sari
Keyword(s):  
Carbon Source ◽  
Nitrogen Source ◽  
Vitamin B1 ◽  
Vitamin B2 ◽  
Static Culture

SRC-4 starin is one of bacteria sellulose producing strains. It was obtained from the rottencoconut meat from Semplak, Bogor. The objective of this study is to obtain the optimumcomposition of modified HS medium to produce cellulose, by increasing yeast extractconcentration and also combination of carbon and vitamin sources. The production of celluloseby SRC-4 was done by 18 treatments on static culture. The increasing of yeast extractconcentration, combination of carbon and vitamin sources gave significant effect to theproduction of cellulose. The highest yield of cellulose was produced at the treatment consist of1.0 % yeat extract (as nitrogen source), 1 % glucose + 1 % glycerol (as carbon source) and0.164 ppm vitamin B1 + 0.020 ppm vitamin B2 (as vitamin source).

Domestic Outsourcing and Workers’ Bargaining Power in a Simple Production System

2020 ◽  
Vol 39 (1) ◽  
pp. 42-56
Author(s):  
Aldo Barba
Keyword(s):  
Technical Progress ◽  
Technical Change ◽  
Production System ◽  
Bargaining Power ◽  
Wide Range ◽  
Regulated Firms ◽  
Domestic Outsourcing ◽  
A New Technique ◽  
Distributive Conflict ◽  
Simple Production

Abstract Outsourcing is normally conceived as the result of a cost-minimizing choice of a new technique that also implies a redefinition of the boundaries between firms and sectors. In this paper, we will argue instead that many outsourcing activities do not necessarily imply technical change and that the phenomenon can be explained by placing it in connection with the radical modification of the way in which wages are set for workers in a wide range of poorly regulated firms and industries. More than as an aspect of the spread of technical progress, outsourcing will be analyzed as an important mechanism through which workers are divided and their bargaining power is weakened, thus changing the outcome of the distributive conflict between profit and wages.

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