Biocontrol of wood-rotting fungi withStreptomyces violaceusnigerXL-2

2006 ◽  
Vol 52 (9) ◽  
pp. 805-808 ◽  
Author(s):  
Nilanshu Shekhar ◽  
Debaditya Bhattacharya ◽  
Dishant Kumar ◽  
Rajinder K Gupta

During the previous decade, chitinases have received increased attention because of their wide range of applications. Chito-oligomers produced by enzymatic hydrolysis of chitin have been of interest in recent years because of their broad applications in medical, agricultural, and industrial applications, such as antibacterial, antifungal, hypo cholesterolemic, and antihypertensive activity, and as food quality enhancer. Fungal cell walls being rich in chitin also enable the use of chitinases in biocontrol of fungal pathogens, as bio-fungicides. An actinomycete was isolated from the bark of trees of Dehradun in India and was later identified as Streptomyces violaceusniger. This strain exhibits strong antagonism towards various wood-rotting fungi, such as Phanerochaete chrysosporium, Postia placenta, Coriolus versicolor, and Gloeophyllum trabeum. Further, studies showed an extracellular bioactive compound was responsible for the antagonism. The conditions for the production of this biocontrol agent were optimized, and the effects of various stress factors (like nitrogen-deficient media, carbon-deficient media, etc.) were studied. The presence of chitin in the growth media was found to be an essential factor for the active production of the biocontrol agent. The pH and temperature optima for the biocontrol agent were determined. Purification and characterization of this specific biocontrol agent was performed through anion exchange chromatography using a DEAE–cellulose column, and a single protein band was obtained on a 10% sodium dodecyl sulfate – polyacrylamide gel. The protein was later identified as a 28 kDa endo chitinase by MALDI–TOF (matrix-assisted laser desorption ionization – time of flight) and by a chitobiose activity assay.Key words: actinomycetes, biocontrol agents, Streptomyces violaceusniger, chitinase.

2020 ◽  
Vol 8 (8) ◽  
pp. 1183
Author(s):  
Benjamin Trudgeon ◽  
Markus Dieser ◽  
Narayanaganesh Balasubramanian ◽  
Mitch Messmer ◽  
Christine M. Foreman

Surfactants, both synthetic and natural, are used in a wide range of industrial applications, including the degradation of petroleum hydrocarbons. Organisms from extreme environments are well-adapted to the harsh conditions and represent an exciting avenue of discovery of naturally occurring biosurfactants, yet microorganisms from cold environments have been largely overlooked for their biotechnological potential as biosurfactant producers. In this study, four cold-adapted bacterial isolates from Antarctica are investigated for their ability to produce biosurfactants. Here we report on the physical properties and chemical structure of biosurfactants from the genera Janthinobacterium, Psychrobacter, and Serratia. These organisms were able to grow on diesel, motor oil, and crude oil at 4 °C. Putative identification showed the presence of sophorolipids and rhamnolipids. Emulsion index test (E24) activity ranged from 36.4–66.7%. Oil displacement tests were comparable to 0.1–1.0% sodium dodecyl sulfate (SDS) solutions. Data presented herein are the first report of organisms of the genus Janthinobacterium to produce biosurfactants and their metabolic capabilities to degrade diverse petroleum hydrocarbons. The organisms’ ability to produce biosurfactants and grow on different hydrocarbons as their sole carbon and energy source at low temperatures (4 °C) makes them suitable candidates for the exploration of hydrocarbon bioremediation in low-temperature environments.


1972 ◽  
Vol 130 (1) ◽  
pp. 121-132 ◽  
Author(s):  
J. P. Kitcher ◽  
P. W. Trudgill ◽  
J. S. Rees

1. 2-Furoyl-CoA hydroxylase of Pseudomonas putida F2 has been purified 60-fold by a combination of (NH4)2SO4 fractionation, DEAE-cellulose chromatography and agarose chromatography. 2. The purified enzyme catalyses the formation of 5-hydroxy-2-furoyl-CoA, which tautomerizes to form 5-oxo-Δ2-dihydro-2-furoyl-CoA. 3. The enzyme has a requirement for an electron acceptor that can be satisfied by a membrane preparation from 2-furoate-grown Ps. putida F2 or by artificial electron acceptors, and so presumably the incorporated oxygen atom is derived from water rather than molecular oxygen. 4. The enzyme is a large protein with a molecular weight of 3.27×106 and is disrupted to form inactive subunits in the presence of 0.2% (w/v) sodium dodecyl sulphate. It has a pH optimum of 8.5–9.5, a Km for 2-furoyl-CoA of 20.2μm and an absorption spectrum with a trough at 265nm and a single peak at 273nm. No absorption peaks are detectable in the visible region of the spectrum. 5. The enzyme is resistant to the effects of a wide range of potential inhibitors, but is inhibited by the copper-chelating agents bathocuproin and cuprizone, though not by sodium diethyldithiocarbamate. 6. Flavins are absent and the iron content does not show a sustained increase during purification. The copper content of the protein increases in close correlation with the increase in specific activity during purification. 7. A catalytic sequence for the hydroxylation of 2-furoyl-CoA by a copper protein is proposed.


1979 ◽  
Vol 177 (2) ◽  
pp. 509-520 ◽  
Author(s):  
R Casey

The potential of immunoaffinity chromatography as a means of purifying legumin from a wide range of Pisum (pea) types was assessed. The method required small amounts of highly purified legumin from a single Pisum type, and this was obtained by salting out with (NH4)2SO4 followed by zonal isoelectric precipitation, ion-exchange chromatography on DEAE-cellulose and sucrose-density-gradient centrifugation. Some physiocochemical properties of purified legumin were determined, a number of which (Strokes radius, subunit molecular weights, subunit N-terminal residues and subunit molar ratios) have not previously been reported for Pisum legumin. Examination of Pisum legumin by two-dimensional gel isoelectric focusing/electrophoresis indicated the existence of extensive subunit heterogeneity, and polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate showed apparent variation in the nature of this heterogeneity from one Pisum variety to another. Despite this variation, immunoaffinity chromatography on immobilized anti-legumin (which was prepared by affinity chromatography on the immubolized purified legumin from the single Pisum type) was shown to be a generally applicable method for the purification of undegraded legumin from a range of pisum types, including two primate lines.


Author(s):  
Ashwini Nilesh Puntambekar ◽  
Manjusha Sudhakar Dake

  Objective: The main objective of this study is to investigate the industrial applications of a thermophillic alkaline protease from a hot water spring bacterial isolate “A” and to study its production, optimization, and purification.Methods: The alkaline protease was produced using shake flask studies maintaining a pH of 9.0 and a temperature of 50°C. Optimization studies of the enzyme were carried out using variable pH, temperature, organic carbon, and nitrogen sources followed by purification of the enzyme using DEAE-cellulose ion exchange chromatography technique. Stability of the enzyme was analyzed in the presence of organic solvents and surfactants. The efficiency of the enzyme in the removal of proteinaceous stains in the presence of strong detergents under extreme conditions was assessed. The fibrinolytic activity of the enzyme in dissolving the blood clot was confirmed.Results: The isolated alkaline protease was purified to homogeneity with a 16-fold increase. Media optimization studies revealed that 1% glucose and 1 % casein-induced the production of alkaline protease. The purified enzyme retained stability in the presence of ethanol, methanol, and acetone and surfactants such as 0.5% (w/v) sodium dodecyl sulfate (SDS) and 0.5% (v/v) Triton-X-100. The isolated alkaline protease successfully removed the proteinaceous stains and showed significant results in the dissolution of blood clot.Conclusion: The above experimental results confirm that the isolated enzyme has both thermophilic and alkaliphilic protease properties. Thereby the enzyme finds promising industrial applications even in extreme conditions.


2009 ◽  
Vol 36 (7) ◽  
pp. 1253-1264 ◽  
Author(s):  
Anjali Singhal ◽  
Gaurav Choudhary ◽  
Indu Shekhar Thakur

Cryptococcus albidus , isolated from the sediments of Century Pulp and Paper Mill, Lalkuan, Nainital, Uttarakhand, India, produced a copper containing oxidase, laccase, that was capable of degrading environmental pollutants. Bagasse was the most efficient inducer for laccase production. The Taguchi approach was used to optimize the growth media for five factors, i.e., pH, copper sulphate, carbon, nitrogen, and the inducer at four levels using an M-16 orthogonal array. The optimum conditions for laccase production were pH (6), CuSO4(2 mmol/L), meat peptone (0.5%), glucose (0.1%), and bagasse (1.0%). After optimization, laccase production increased seven times from 32 to 219 IU/mg. The inducer (bagasse) had maximum effect on laccase production leading to 52% increase, while pH had minimum effect with 7% increase. Growth media with laccase activity (2 U/mL) was applied for the bioremediation of dyes, effluent, and chemical compounds. These experiments showed that the growth media with laccase activity (2 U/mL) produced by Cryptococcus albidus had good potential for bioremediation of toxic and recalcitrant compounds. Further, the laccase enzyme extracted from the growth media was fractionated by DEAE-cellulose ion-exchange chromatography, and the molecular weight of the enzyme determined by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS–PAGE) was found to be 64 kDa. The activity of laccase was confirmed by native PAGE, in which ABTS was used for staining gel.


2019 ◽  
Author(s):  
James Ewen ◽  
Carlos Ayestaran Latorre ◽  
Arash Khajeh ◽  
Joshua Moore ◽  
Joseph Remias ◽  
...  

<p>Phosphate esters have a wide range of industrial applications, for example in tribology where they are used as vapour phase lubricants and antiwear additives. To rationally design phosphate esters with improved tribological performance, an atomic-level understanding of their film formation mechanisms is required. One important aspect is the thermal decomposition of phosphate esters on steel surfaces, since this initiates film formation. In this study, ReaxFF molecular dynamics simulations are used to study the thermal decomposition of phosphate esters with different substituents on several ferrous surfaces. On Fe<sub>3</sub>O<sub>4</sub>(001) and α-Fe(110), chemisorption interactions between the phosphate esters and the surfaces occur even at room temperature, and the number of molecule-surface bonds increases as the temperature is increased from 300 to 1000 K. Conversely, on hydroxylated, amorphous Fe<sub>3</sub>O<sub>4</sub>, most of the molecules are physisorbed, even at high temperature. Thermal decomposition rates were much higher on Fe<sub>3</sub>O<sub>4</sub>(001) and particularly α-Fe(110) compared to hydroxylated, amorphous Fe<sub>3</sub>O<sub>4</sub>. This suggests that water passivates ferrous surfaces and inhibits phosphate ester chemisorption, decomposition, and ultimately film formation. On Fe<sub>3</sub>O<sub>4</sub>(001), thermal decomposition proceeds mainly through C-O cleavage (to form surface alkyl and aryl groups) and C-H cleavage (to form surface hydroxyls). The onset temperature for C-O cleavage on Fe<sub>3</sub>O<sub>4</sub>(001) increases in the order: tertiary alkyl < secondary alkyl < primary linear alkyl ≈ primary branched alkyl < aryl. This order is in agreement with experimental observations for the thermal stability of antiwear additives with similar substituents. The results highlight surface and substituent effects on the thermal decomposition of phosphate esters which should be helpful for the design of new molecules with improved performance.</p>


Alloy Digest ◽  
1970 ◽  
Vol 19 (11) ◽  

Abstract PLATINUM is a soft, ductile, white metal which can be readily worked either hot or cold. It has a wide range of industrial applications because of its excellent corrosion and oxidation resistance and its high melting point. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Pt-1. Producer or source: Matthey Bishop Inc..


2020 ◽  
Vol 16 (4) ◽  
pp. 537-542
Author(s):  
Zhigacheva Irina ◽  
Volodkin Aleksandr ◽  
Rasulov Maksud

Background: One of the main sources of ROS in stress conditions is the mitochondria. Excessive generation of ROS leads to oxidation of thiol groups of proteins, peroxidation of membrane lipids and swelling of the mitochondria. In this regard, there is a need to search for preparationsadaptogens that increase the body's resistance to stress factors. Perhaps, antioxidants can serve as such adaptogens. This work aims at studying the effect of antioxidant; the potassium anphen in a wide range of concentrations on the functional state of 6 day etiolated pea seedlings mitochondria (Pisum sativum L). Methods: The functional state of mitochondria was studied per rates of mitochondria respiration, by the level of lipid peroxidation and study of fatty acid composition of mitochondrial membranes by chromatography technique. Results: Potassium anphen in concentrations of 10-5 - 10-8 M and 10-13-10-16 prevented the activation of LPO in the mitochondrial membranes of pea seedlings, increased the oxidation rates of NAD-dependent substrates and succinate in the respiratory chain of mitochondria that probably pointed to the anti-stress properties of the drug. Indeed, the treatment of pea seeds with the preparation in concentrations of 10-13 M prevented the inhibition of growth of seedlings in conditions of water deficiency. Conclusion: It is assumed that the dose dependence of the biological effects of potassium anphen and the manifestation of these effects in ultra-low concentrations are due to its ability in water solutions to form a hydrate containing molecular ensembles (structures).


2020 ◽  
Vol 15 (1) ◽  
pp. 787-796 ◽  
Author(s):  
Marek Kieliszek ◽  
Kamil Piwowarek ◽  
Anna M. Kot ◽  
Katarzyna Pobiega

AbstractCellular biomass of microorganisms can be effectively used in the treatment of waste from various branches of the agro-food industry. Urbanization processes and economic development, which have been intensifying in recent decades, lead to the degradation of the natural environment. In the first half of the 20th century, problems related to waste management were not as serious and challenging as they are today. The present situation forces the use of modern technologies and the creation of innovative solutions for environmental protection. Waste of industrial origin are difficult to recycle and require a high financial outlay, while the organic waste of animal and plant origins, such as potato wastewater, whey, lignin, and cellulose, is dominant. In this article, we describe the possibilities of using microorganisms for the utilization of various waste products. A solution to reduce the costs of waste disposal is the use of yeast biomass. Management of waste products using yeast biomass has made it possible to generate new metabolites, such as β-glucans, vitamins, carotenoids, and enzymes, which have a wide range of industrial applications. Exploration and discovery of new areas of applications of yeast, fungal, and bacteria cells can lead to an increase in their effective use in many fields of biotechnology.


Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1711
Author(s):  
Heba A. Gad ◽  
Autumn Roberts ◽  
Samirah H. Hamzi ◽  
Haidy A. Gad ◽  
Ilham Touiss ◽  
...  

Jojoba is a widely used medicinal plant that is cultivated worldwide. Its seeds and oil have a long history of use in folklore to treat various ailments, such as skin and scalp disorders, superficial wounds, sore throat, obesity, and cancer; for improvement of liver functions, enhancement of immunity, and promotion of hair growth. Extensive studies on Jojoba oil showed a wide range of pharmacological applications, including antioxidant, anti-acne and antipsoriasis, anti-inflammatory, antifungal, antipyretic, analgesic, antimicrobial, and anti-hyperglycemia activities. In addition, Jojoba oil is widely used in the pharmaceutical industry, especially in cosmetics for topical, transdermal, and parenteral preparations. Jojoba oil also holds value in the industry as an anti-rodent, insecticides, lubricant, surfactant, and a source for the production of bioenergy. Jojoba oil is considered among the top-ranked oils due to its wax, which constitutes about 98% (mainly wax esters, few free fatty acids, alcohols, and hydrocarbons). In addition, sterols and vitamins with few triglyceride esters, flavonoids, phenolic and cyanogenic compounds are also present. The present review represents an updated literature survey about the chemical composition of jojoba oil, its physical properties, pharmacological activities, pharmaceutical and industrial applications, and toxicity.


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