scholarly journals CONSTITUENTS OF ELEMENTARY BODIES OF VACCINIA

1941 ◽  
Vol 74 (1) ◽  
pp. 69-80 ◽  
Author(s):  
Charles L. Hoagland ◽  
S. M. Ward ◽  
Joseph E. Smadel ◽  
Thomas M. Rivers
Keyword(s):  
Cytochrome Oxidase ◽  
Potassium Cyanide ◽  
Emission Spectra ◽  
Fold Increase ◽  
Dry Weight ◽  
Copper Component ◽  
Ph Range

A search by means of spectroscopic and enzymatic techniques has failed to demonstrate either cytochrome or cytochrome oxidase in purified elementary bodies of vaccinia. A constituent of the virus which catalyzes the oxidation of cystein has been found and identified as copper in a concentration amounting to 0.05 per cent of the dry weight of the virus. The copper constituent was not removed by repeated washing, ultrafiltration, dialysis against 0.1 molar potassium cyanide, or by electrodialysis over a pH range which did not inactivate the virus. During the process of purification of the virus a 25-fold increase of the copper constituent was observed. Emission spectra obtained from the dry virus also revealed copper but no significant traces of other metallic substances. No biological rôle can yet be ascribed to the copper component of virus.

The ability of Distichlis spicata to grow sustainably within a saline discharge zone while improving the soil chemical and physical properties

Soil Research ◽  
2008 ◽  
Vol 46 (1) ◽  
pp. 37 ◽  
Author(s):  
M. R. Sargeant ◽  
C. Tang ◽  
P. W. G. Sale
Keyword(s):  
Electrical Conductivity ◽  
Hydraulic Conductivity ◽  
Physical Properties ◽  
Soil Nitrogen ◽  
Fold Increase ◽  
Dry Weight ◽  
Saturated Hydraulic Conductivity ◽  
Distichlis Spicata ◽  
Discharge Zone ◽  
Spatial And Temporal Variation

Landholder observations indicate that the growth of Distichlis spicata in saline discharge sites improves the soil condition. An extensive soil sampling survey was conducted at the Wickepin field site in Western Australia, where D. spicata had been growing for 8 years, to test the hypothesis that this halophytic grass will make improvements in chemical and physical properties of the soil. Soil measurements included saturated hydraulic conductivity, water-stable aggregates, root length and dry weight, electrical conductivity, pH, and soil nitrogen and carbon. Results confirm that marked differences in soil properties occurred under D. spicata. For example, a 12-fold increase in saturated hydraulic conductivity occurred where D. spicata had been growing for 8 years, compared to adjacent control soil where no grass had been growing. There were also improvements in aggregate stability, with the most notable improvements in the top 0.10 m of soil, again with the greatest improvements occurring where 8 years of growth had occurred. Soil nitrogen and carbon increased under the sward, with the biggest increases occurring in the top 0.10 m of soil. Electrical conductivity measurements were more variable, mostly due to the large spatial and temporal variation encountered. However, the findings generally support the proposition that the growth of D. spicata does not lead to an accumulation of salt within the rooting zone.

scholarly journals Effects of pH and Aeration on Sclerotium rolfsii sacc. Mycelial Growth, Sclerotial Production and Germination

2018 ◽  
Vol 7 (3) ◽  
pp. 123-129 ◽  
Author(s):  
Fakher Ayed ◽  
Hayfa Jabnoun-Khiareddine ◽  
Rania Aydi-Ben-Abdallah ◽  
Mejda Daami-Remadi
Keyword(s):  
Mycelial Growth ◽  
Sclerotium Rolfsii ◽  
Dry Weight ◽  
Ph Values ◽  
Effects Of Ph ◽  
Ph Range ◽  
Sclerotial Development ◽  
Sclerotial Germination

Sclerotium rolfsii is one of the devastating soilborne fungus responsible for significant plant losses. The effects of pH and aeration on pathogen mycelial growth, sclerotial production and germination were investigated for three Tunisian isolates. Optimal mycelial growth occurred at pH 6 for Sr2 and Sr3 isolates and at pH 6-7 for Sr1. Dry mycelial growth was optimum at pH values ranging between 4 and 7. Sclerotial initiation started on the 3rd day of incubation at all pH values tested and mature sclerotia were formed after 6 to 12 days. Optimal sclerotial production was noted at pH 5. The dry weight of 100 sclerotia varied depending on isolates and pH and occurred at pH range 4-7. At pH 9, mycelial growth, sclerotial production and dry weight of 100 sclerotia were restricted. The optimum sclerotial germination, noted after 24 h of incubation, varied depending on isolates and pH and occurred at pH 4-9. Mycelial growth was optimum in aerated plates with a significant isolates x aeration treatments interaction. Sclerotial initiation occurred at the 3rd day of incubation and mature sclerotia were observed after 6-9 days. Sclerotial development was very slow in completely sealed plates and dark sclerotia were produced only after 15 days of incubation. The highest sclerotial yields were noted in aerated plates. The highest dry weight of 100 sclerotia for Sr1 isolate was recorded in ½ sealed, no sealed and completely sealed plates, while for Sr2, it was noted in ½ and ⅔ sealed plates. For Sr3, the maximum dry weight of 100 sclerotia was recorded in ½, ⅔ and completely sealed plates. Germination of S. rolfsii sclerotia, after 24 h of incubation, did not vary significantly depending on aeration treatments and ranged from 90 to 100% for all isolates.

scholarly journals Isolation and Assessment of the Symbiotic Efficiency of Faba bean (Vicia faba L.) Nodulating Rhizobial Isolates from Eastern Hararghe Highlands of Ethiopia

2021 ◽  
Vol 9 (2) ◽  
pp. 91-105
Author(s):  
Mulugeta Mekonnen ◽  
Ameha Kebede
Keyword(s):  
Vicia Faba ◽  
Faba Bean ◽  
Dry Weight ◽  
Symbiotic Efficiency ◽  
Shoot Dry Weight ◽  
Nacl Concentration ◽  
Vicia Faba L ◽  
Positive Correlations ◽  
Ph Range ◽  
Rhizobial Isolates

This particular work was devoted to isolate and assess the symbiotic efficiency of faba bean (Vicia faba L.)-nodulating rhizobia isolate at few faba bean growing areas of the eastern Hararghe highlands of Ethiopia. Overall 50 rhizobia isolates were obtained from soil samples of three Woredas (districts) of the eastern Hararghe highlands using the host trap method. Out of these 50 isolates, 40 were presumptively identified as rhizobia. Among these 40 rhizobia isolates, only 31 were successful to nodulate faba bean, and authenticated as true faba bean nodulating rhizobia. Concerning the symbiotic efficiency, about 52%, 35%, and 13% of the rhizobial isolates were found to be highly effective, effective, and lowly-effective, respectively. The correlation data on the sand experiment displayed that nodule dry weight was associated positively and significantly (r = 0.494, p<0.05) with shoot dry weight while shoot dry weight was associated positively and significantly (r=0.41, p<0.05) with plant total nitrogen. Positive correlations were also observed concerning shoot dry weight and dry weight of nodules (r = 0.7, p<0.05) on unsterilized soil. Among the observed rhizobium isolates, EHHFR (4A, 6A) showed the highest symbiotic efficiency above 110%, tolerated NaCl concentration ranging from 2% to 6% and 2% to 8%, respectively, and a pH range of 4.5 to 8 and 5 to 8, respectively. Thus, based on their symbiotic efficiency at the greenhouse level and relative tolerance to extreme conditions these faba bean nodulating rhizobia isolates were recommended to be used as nominees for the future development of faba bean rhizobial inoculants after being tested on field conditions.

scholarly journals Introducing a Thermo-Alkali-Stable, Metallic Ion-Tolerant Laccase Purified From White Rot Fungus Trametes hirsuta

2021 ◽  
Vol 12 ◽  
Author(s):  
Jing Si ◽  
Hongfei Ma ◽  
Yongjia Cao ◽  
Baokai Cui ◽  
Yucheng Dai
Keyword(s):  
Specific Activity ◽  
Endocrine Disrupting Chemicals ◽  
Environmental Pollutants ◽  
Fold Increase ◽  
Industrial Applications ◽  
White Rot ◽  
White Rot Fungus ◽  
Metallic Ions ◽  
Trametes Hirsuta ◽  
Ph Range

This study introduces a valuable laccase, designated ThLacc-S, purified from white rot fungus Trametes hirsuta. ThLacc-S is a monomeric protein in nature with a molecular weight of 57.0 kDa and can efficiently metabolize endocrine disrupting chemicals. The enzyme was successfully purified to homogeneity via three consecutive steps consisting of salt precipitation and column chromatography, resulting in a 20.76-fold increase in purity and 46.79% yield, with specific activity of 22.111 U/mg protein. ThLacc-S was deciphered as a novel member of the laccase family and is a rare metalloenzyme that contains cysteine, serine, histidine, and tyrosine residues in its catalytic site, and follows Michaelis-Menten kinetic behavior with a Km and a kcat/Km of 87.466 μM and 1.479 s–1μM–1, respectively. ThLacc-S exerted excellent thermo-alkali stability, since it was markedly active after a 2-h incubation at temperatures ranging from 20 to 70°C and retained more than 50% of its activity after incubation for 72 h in a broad pH range of 5.0–10.0. Enzymatic activities of ThLacc-S were enhanced and preserved when exposed to metallic ions, surfactants, and organic solvents, rendering this novel enzyme of interest as a green catalyst for versatile biotechnological and industrial applications that require these singularities of laccases, particularly biodegradation and bioremediation of environmental pollutants.

scholarly journals Effect of Ultraviolet-C Radiation and Melatonin Stress on Biosynthesis of Antioxidant and Antidiabetic Metabolites Produced in In Vitro Callus Cultures of Lepidium sativum L.

2019 ◽  
Vol 20 (7) ◽  
pp. 1787 ◽  
Author(s):  
Muhammad Asad Ullah ◽  
Duangjai Tungmunnithum ◽  
Laurine Garros ◽  
Samantha Drouet ◽  
Christophe Hano ◽  
...  
Keyword(s):  
Callus Culture ◽  
High Performance ◽  
Biological Activities ◽  
Fold Increase ◽  
Dry Weight ◽  
Callus Cultures ◽  
Lepidium Sativum ◽  
Uv C ◽  
Lepidium Sativum L

Lepidium sativum L. is a rich source of polyphenols that have huge medicinal and pharmaceutical applications. In the current study, an effective abiotic elicitation strategy was designed for enhanced biosynthesis of polyphenols in callus culture of L. sativum. Callus was exposed to UV-C radiations for different time intervals and various concentrations of melatonin. Secondary metabolites were quantified by using high-performance liquid chromatography (HPLC). Results indicated the total secondary metabolite accumulation of nine quantified compounds was almost three fold higher (36.36 mg/g dry weight (DW)) in melatonin (20 μM) treated cultures, whereas, in response to UV-C (60 min), a 2.5 fold increase (32.33 mg/g DW) was recorded compared to control (13.94 mg/g DW). Metabolic profiling revealed the presence of three major phytochemicals, i.e., chlorogenic acid, kaemferol, and quercetin, in callus culture of L. sativum. Furthermore, antioxidant, antidiabetic, and enzymatic activities of callus cultures were significantly enhanced. Maximum antidiabetic activities (α-glucosidase: 57.84%; α-amylase: 62.66%) were recorded in melatonin (20 μM) treated callus cultures. Overall, melatonin proved to be an effect elicitor compared to UV-C and a positive correlation in these biological activities and phytochemical accumulation was observed. The present study provides a better comparison of both elicitors and their role in the initiation of physiological pathways for enhanced metabolites biosynthesis in vitro callus culture of L. sativum.

Influence of pH on the Absorption and Fluorescence Spectra of 6,7-Dihydroxycoumarin in Aqueous Solution

1982 ◽  
Vol 37 (3) ◽  
pp. 262-265 ◽  
Author(s):  
Jerzy Grzywacz ◽  
Stanisława Taszner
Keyword(s):  
Aqueous Solution ◽  
Fluorescence Spectra ◽  
Singlet State ◽  
Ph Value ◽  
Emission Spectra ◽  
Excited Singlet ◽  
Acid Base ◽  
Wide Ph Range ◽  
Ph Range ◽  
Influence Of Ph

Abstract Absorption and emission spectra of 6,7-dihydroxycoumarin [6,7-DHC] in aqueous solution over a wide pH range are reported. The absorption spectra proved to be strongly sensitive to the pH-value of the solution, whereas the emission spectra change in this range only insignificantly. An interpretation is attempted on the basis of the differences of the acid-base properties of the 6,7-DHC molecule in its ground and excited singlet state. For this purpose the pKa's and pKax's values have been calculated. It has been stated that in the excited state the phototautomer form is very unlikely.

scholarly journals Critical conditions of struvite growth and recovery using MgO in pilot scale crystallization plant

2020 ◽  
Vol 81 (12) ◽  
pp. 2511-2521 ◽  
Author(s):  
Nari Park ◽  
Hyangyoun Chang ◽  
Yeoju Jang ◽  
Hyunman Lim ◽  
Jinhong Jung ◽  
...  
Keyword(s):  
Pilot Plant ◽  
Wastewater Treatment Plants ◽  
Weight Fraction ◽  
Dry Weight ◽  
Xrd Analysis ◽  
Pilot Scale ◽  
Critical Conditions ◽  
Side Stream ◽  
Struvite Crystallization ◽  
Ph Range

Abstract The struvite crystallization process can recover struvite crystals as a valuable slow-release fertilizer from the side stream of wastewater treatment plants (WWTPs). The purpose of this study is to demonstrate the crystal growth characteristics and determine the appropriate recovery criteria for a struvite crystallization pilot plant. A pilot plant (8.6 m3/d) was designed with a feeding system of MgO (magnesium oxide), a pH controller, and a hydrocyclone for recovering struvite; the plant was operated for 42 hours at a pH range of 8.25–8.5. The removal efficiencies for PO4-P and NH4-N were 82.5–90.7% and 13.4–22.9%, respectively. The struvite recovered from the hydrocyclone was sifted using standard sieves and analyzed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The dry weight fraction of the precipitate in the 300–600 μm range increased gradually from 7% to 74% in 18 hours. The XRD analysis revealed that the crystalline structure of the precipitate in the 150–600 μm range indicates struvite without any peaks of MgO, Mg(OH)2, and MgCO3. This indicates that the critical conditions for recovering struvite from the side-stream of WWTPs are an operation period of 18 hours and a crystal size greater than 300 μm.

Laboratory adaptation ofBactrocera tryoni(Diptera: Tephritidae) decreases mating age and increases protein consumption and number of eggs produced per milligram of protein

2004 ◽  
Vol 94 (6) ◽  
pp. 517-524 ◽  
Author(s):  
A. Meats ◽  
H.M. Holmes ◽  
G.L. Kelly
Keyword(s):  
Dietary Protein ◽  
Egg Size ◽  
Adult Life ◽  
Fold Increase ◽  
Dry Weight ◽  
Egg Load ◽  
Fresh Weight ◽  
Bactrocera Tryoni ◽  
Laboratory Adaptation

AbstractA significant reduction in age of mating occurred during the first four generations (G1–G4) of laboratory adaptation of wildBactrocera tryoni(Froggatt) and this was associated with the earlier attainment of peak egg load although no significant differences were detected in the peak egg load itself. A long term laboratory (LTL) strain had a significantly earlier mating age and higher peak egg load than flies of wild origin or those from the first four laboratory generations. The amount of protein consumed by females in the first week of adult life was significantly higher in the LTL strain than in flies of wild origin or G1–G4 but there were no significant changes (or only slight changes) with laboratory adaptation in the amounts of protein consumed up to the ages of mating and peak egg load. Laboratory adaptation resulted in no significant changes in egg size, egg dry weight, puparial fresh weight and the dry weight of newly emerged females. The large increase in fecundity with laboratory adaptation is associated with a 4- to 5-fold increase in the rate of conversion of dietary protein to eggs (i.e. eggs produced per mg of protein consumed).

scholarly journals Origin of the membrane potential in plasmodial droplets of Physarum polycephalum. Evidence for an electrogenic pump.

1981 ◽  
Vol 78 (6) ◽  
pp. 637-655 ◽  
Author(s):  
H Kuroda ◽  
R Kuroda
Keyword(s):  
Membrane Potential ◽  
Potassium Cyanide ◽  
Equilibrium Potential ◽  
Ion Pump ◽  
Electrophysiological Studies ◽  
Concentration Changes ◽  
Electrogenic Ion Pump ◽  
Ph Range ◽  
Physarum Plasmodia ◽  
Spherical Droplets

Spherical droplets, derived from Physarum plasmodia by incubation in 10 mM caffeine, seemed to be an excellent system for electrophysiological studies because they were large (less than or equal to 300 micrometer in diameter) and because they tolerated intracellular electrodes filled with 3 M KCl and 10 mM EDTA for a few hours. Intact plasmodia, by contrast, gave valid records for only a few minutes. Under standard conditions ([K+]o = 1 mM, [Na+]o = 5 mM, [Ca++]0 = 0.5 mM, [Mg++]o = 2 mM, and [Cl-]o = 6 mM at pH 7.0), the potential difference across droplet membranes was -80 to -120mV, interior negative. The membrane potential was only slightly sensitive to concentration changes for the above-mentioned ions, and was far negative to the equilibrium diffusion potentials calculated from the known internal contents of K, Na, Ca, Mg, and CL (29.4, 1.6, 3.7, 6.5, and 27.8 mmol/kg, respectively). Variations of external pH did have a strong influence on the membrane potential, yielding a slope of 59 mV/pH between pH 6.5 and 5.5. In this pH range, however, the equilibrium potential for H+ (assuming 6.2 less than or equal to pHi less than or equal to 7.0) was greater than 75 mV positive to the observed membrane potential. Membrane potential was directly responsive to metabolic events, being lowered by potassium cyanide, and by cooling from 25 to 12 degrees C. This ensemble of results strongly indicates that the major component of membrane potential in plasmodial droplets of Physarum is generated by an electrogenic ion pump, probably one extruding H+ ions.

scholarly journals THE DEVELOPMENT IN VITRO OF PARTICLES FROM CYTOPLASM

1958 ◽  
Vol 107 (5) ◽  
pp. 769-782 ◽  
Author(s):  
Eric L. Nelson
Keyword(s):  
Deoxyribonucleic Acid ◽  
Dry Weight ◽  
Weight Basis ◽  
Spherical Particles ◽  
Red Cell ◽  
Practical Applications ◽  
Unknown Factor ◽  
Development In Vitro ◽  
Ph Range

Spherical particles, 1 to 10 microns in diameter, resulted from the incubation at 37°C. of distilled water lysates of erythrocytes with deoxyribonucleic acid (DNA). The particles consisted of 88 per cent hemoglobin and 12 per cent DNA (dry weight basis). An unknown factor, presumably an enzyme, present only in fresh red cell lysates, was required for particle development. Particle size was a function of the pH of the reaction mixture. The pH range was 4.8–5.8. It was possible to trap extraneous proteins and polysaccharides in pockets within the hemoglobin particles during their development to the exclusion of some of the hemoglobin. The amount of any one substance so trapped was proportional to its concentration in the reaction mixture. Some practical applications of the particles, as a means for making particulate various soluble substances (enzymes, antigens, antibiotics), are suggested.

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