Environmental factors affecting the antagonism of Pseudomonas cepacia against Trichoderma viride

1991 ◽  
Vol 37 (11) ◽  
pp. 880-884 ◽  
Author(s):  
Ram S. Upadhyay ◽  
Luisa Visintin ◽  
R. K. Jayaswal
Keyword(s):  
Antifungal Activity ◽  
Environmental Factors ◽  
Key Words ◽  
Environmental Conditions ◽  
Trichoderma Viride ◽  
Carbon Sources ◽  
Ammonium Nitrogen ◽  
Antagonistic Activity ◽  
Pseudomonas Cepacia ◽  
Factors Affecting

Antagonistic activity of the bacterium Pseudomonas cepacia against Trichoderma viride was greatly influenced by nutritional and environmental conditions. Xylose and trehalose strongly enhanced the antifungal activity of P. cepacia, whereas mannitol and glucose had little effect. The carbon sources that enhanced the antagonistic activity also inhibited sporulation of T. viride. Antagonism of P. cepacia was enhanced by ammonium nitrogen; however, with nitrite or nitrate there was only a little antagonism. The antagonism of P. cepacia was optimal at pH 5.0. Although P. cepacia showed maximum antagonism against T. viride at 37 °C, the antagonism was fairly good at temperatures as low as 18 °C, indicating that there is a broad range of temperature for the antifungal activity of P. cepacia. Key words: antagonism, environmental factors, Pseudomonas cepacia, Trichoderma viride.

Environmental factors affecting 17th–19th century whaling in the Greenland Sea

Polar Record ◽  
1991 ◽  
Vol 27 (161) ◽  
pp. 77-86 ◽  
Author(s):  
Chesley W. Sanger
Keyword(s):  
Environmental Factors ◽  
19Th Century ◽  
Environmental Conditions ◽  
Detailed Knowledge ◽  
Greenland Sea ◽  
Factors Affecting ◽  
Whale Oil ◽  
Unique Character ◽  
Ice Edge ◽  
Sea Wind

AbstractCommercial pelagic whaling of the 17th–19th centuries in the Greenland Sea was heavily influenced by environmental factors. Much of the fishery took place along a constantly shifting ice-edge, variations in which stamped a unique character on each season's operation. Environmental conditions required expert interpretation, both to procure paying cargoes of whale oil and bone and to survive hazards posed by sea, wind and ice. Detailed knowledge of currents, temperatures and winds enhanced greatly the chance that a master would have a successful voyage.

Error Analysis and Calibration of Infra-Red Temperature Measurement

2013 ◽  
Vol 333-335 ◽  
pp. 290-295
Author(s):  
Ke Qin Bao ◽  
Gu Xiang Ding ◽  
Yi Bo Song
Keyword(s):  
Environmental Factors ◽  
Error Analysis ◽  
Temperature Measurement ◽  
Environmental Conditions ◽  
Electrical Equipment ◽  
Factors Affecting ◽  
Temperature Measuring ◽  
Infra Red ◽  
Main Factors ◽  
Distance Coefficient

R temperature measurement in electrical equipment is more and more used in temperature measurement, but accuracy of temperature measurement is susceptible to outside interference. The main factors affecting the accuracy of measuring temperature, such as environmental factors, equipment emissivity and distance coefficient, are analyzed, the solution has been put forward. In the environmental conditions under the condition of relatively unchanged ,change rule of the temperature value along with the temperature measuring distance changing from 0.7 to 5 meters is found, and temperature value is calibrated . The result after calibrating shows that the method is valid,and error of temperature is less than 0.7°C within 5 meters.

scholarly journals Soils from HNV agriculture systems as source of microorganisms with antifungal activity

2018 ◽  
Vol 2 (4) ◽  
pp. 196-199
Author(s):  
Matei Sorin ◽  
Matei Gabi-Mirela ◽  
Dumitrașcu Monica
Keyword(s):  
Antifungal Activity ◽  
Plant Pathogens ◽  
Culture Media ◽  
Trichoderma Viride ◽  
Culture Method ◽  
Sole Source ◽  
Fungal Species ◽  
Antagonistic Activity ◽  
Dual Culture ◽  
Agriculture Systems

Abstract Soils from rural zones with high natural value (HNV) agriculture systems are an important source of beneficial microbial species that can be useful for various biotechnological purposes, such as transfer of suppressiveness against plant pathogens from suppressive to disease-inducing soils by using inoculation with antagonistic selected strains. The main goal of the paper was to present the results of the research carried out on strains isolated from soil microbial populations in HNV agriculture system (Mureș county, Romania) responsible for specific suppressiveness against soil-borne phytopathogens. The dual culture method was used for assessing the mechanisms involved in antagonism against a plant pathogenic strain from genus Fusarium. The global microbial activity measured as soil respiration was intense. Total counts of bacteria and fungi estimated by dilution plate were also high. The community of heterotrophic aerobic bacteria included 13 species. Associations of fluorescent pseudomonads and actinomycetes were dominant and presented antagonistic activity against Fusarium. Twenty fungal species presented cellulolytic capability evidenced by growth on culture media with cellulose as sole source of carbon. Over cellulolytic capacity, the selected isolate of Trichoderma viride presented antagonistic activity against pathogenic Fusarium strain. Both biochemical mechanism and hyperparasitism were evidenced as involved in its antifungal activity.

Some nutritional and environmental factors affecting growth and production of sclerotia by a strain of Aspergillus niger

1969 ◽  
Vol 15 (8) ◽  
pp. 835-840 ◽  
Author(s):  
V. P. Agnihotri
Keyword(s):  
Aspergillus Niger ◽  
Environmental Factors ◽  
Synergistic Effect ◽  
Magnesium Sulfate ◽  
Sodium Sulfite ◽  
Agar Medium ◽  
Carbon Sources ◽  
Dry Weight ◽  
Factors Affecting ◽  
Nutritional Elements

The effects of two nutritional elements (carbon and sulfur) and two environmental factors (pH and temperature) on growth and sclerotial production of Aspergillus niger were determined on a synthetic agar medium. The fungus grew and produced sclerotia under laboratory conditions on media containing wide ranges of carbon and sulfur sources. Of the 20 carbohydrates tested, only ribose, mannitol, and malonic, fumaric, and citric acids failed to induce production of sclerotia. A synergistic effect was observed on the formation of sclerotia when favorable and unfavorable carbon sources were supplied in different combinations. Of the 14 sulfur compounds tested, magnesium sulfate yielded the highest and sodium sulfite the lowest number of sclerotia. Raising the concentration of magnesium sulfate to 3 g/l increased the number of sclerotium initials and the number and dry weight of those which matured. In general, no correlation occurred between the number of sclerotia formed and their dry weights on different carbon or sulfur sources. Sclerotia were most numerous at pH 7.0 and 35 °C.

Questions on the role of biofilms for the adaptation of microorganisms to unfavorable environmental factors by the example of P. aeruginosa

2020 ◽  
Vol 99 (4) ◽  
pp. 379-383
Author(s):  
Vasily N. Afonyushkin ◽  
N. A. Donchenko ◽  
Ju. N. Kozlova ◽  
N. A. Davidova ◽  
V. Yu. Koptev ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Environmental Factors ◽  
Barrier Function ◽  
Infectious Agent ◽  
Antagonistic Activity ◽  
The Body ◽  
Main Function ◽  
Pathogenic Potential ◽  
The Face

Pseudomonas aeruginosa is a widely represented species of bacteria possessing of a pathogenic potential. This infectious agent is causing wound infections, fibrotic cystitis, fibrosing pneumonia, bacterial sepsis, etc. The microorganism is highly resistant to antiseptics, disinfectants, immune system responses of the body. The responses of a quorum sense of this kind of bacteria ensure the inclusion of many pathogenicity factors. The analysis of the scientific literature made it possible to formulate four questions concerning the role of biofilms for the adaptation of P. aeruginosa to adverse environmental factors: Is another person appears to be predominantly of a source an etiological agent or the source of P. aeruginosa infection in the environment? Does the formation of biofilms influence on the antibiotic resistance? How the antagonistic activity of microorganisms is realized in biofilm form? What is the main function of biofilms in the functioning of bacteria? A hypothesis has been put forward the effect of biofilms on the increase of antibiotic resistance of bacteria and, in particular, P. aeruginosa to be secondary in charcter. It is more likely a biofilmboth to fulfill the function of storing nutrients and provide topical competition in the face of food scarcity. In connection with the incompatibility of the molecular radii of most antibiotics and pores in biofilm, biofilm is doubtful to be capable of performing a barrier function for protecting against antibiotics. However, with respect to antibodies and immunocompetent cells, the barrier function is beyond doubt. The biofilm is more likely to fulfill the function of storing nutrients and providing topical competition in conditions of scarcity of food resources.

ANALYSIS OF INNOVATION ACTIVITIES OF ENTERPRISES OF KAZAKHSTAN

2020 ◽  
Vol 384 (2) ◽  
pp. 137-145
Author(s):  
Zh. Abylkassimova ◽  
G. Orynbekova ◽  
М. Alibayeva ◽  
O. Osadchaya
Keyword(s):  
Key Words ◽  
Added Value ◽  
Human Potential ◽  
Innovation Activity ◽  
Factors Affecting ◽  
Innovation Potential ◽  
Innovation Activities ◽  
Innovation Economy

The article noted that the development of the innovation potential of enterprises in the regions of Kazakhstan contributes to the transition of the innovation economy, where goods with high added value will be produced. The article examines the factors affecting the innovation activity of the regions, considers the dynamics of innovation activity and identifies problems and tools for the development of innovative entrepreneurship. Key words: innovation, innovation activity, region, industrialization, human potential, infrastructure

Antifúngicos poliénicos. Mecanismo de acción y aplicaciones

2020 ◽  
Vol 63 (2) ◽  
pp. 7-17
Author(s):  
Evelyn Rivera-Toledo ◽  
Alan Uriel Jiménez-Delgadillo ◽  
Patricia Manzano-Gayosso
Keyword(s):  
Antifungal Activity ◽  
Key Words ◽  
Secondary Metabolism ◽  
Amphotericin B ◽  
Antifungal Agents ◽  
Fungal Infections ◽  
Variable Number ◽  
Therapeutic Failure ◽  
Morbidity And Mortality ◽  
Clinical Use

The first compounds with specific antifungal activity were identified in the middle of the last century as a product of the secondary metabolism of bacteria of the order Actinomycetales, and their clinical use significantly diminished the morbidity and mortality associated with severe fungal infections. Many of such biosynthetic compounds are characterized by a chemical polygenic structure, with a variable number of carbon-carbon double bonds. Currently, besides polygenic antimycotics, there are other antifungal agents, such as the azole compounds, that have less toxicity in patients; however, cases of therapeutic failure with such compounds have been documented, therefore, the use of polygenics is still the best alternative in such cases. This review presents data about the properties and applications of antifungal-polygenic compounds using amphotericin B as a model. Key words: Amphotericin B; antifungal polyenes; ergosterol

Environmental factors affecting reproducibility of bioremediation field assays in Antarctica

2020 ◽  
Vol 169 ◽  
pp. 102915 ◽  
Author(s):  
L.M. Martínez Álvarez ◽  
L.A.M. Ruberto ◽  
J.M. Gurevich ◽  
W.P. Mac Cormack
Keyword(s):  
Environmental Factors ◽  
Factors Affecting
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