Viscosities and Carbon Dioxide Solubilities of Guanidine Carbonate and Malic Acid-Based Eutectic Solvents

2016 ◽  
Vol 62 (1) ◽  
pp. 348-354 ◽  
Author(s):  
Nouman R. Mirza ◽  
Nathan J. Nicholas ◽  
Yue Wu ◽  
Kathryn H. Smith ◽  
Sandra E. Kentish ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Malic Acid ◽  
Guanidine Carbonate

ON THE EXTRACTION OF ENZYMES FROM SUCCULENT PLANTS

1957 ◽  
Vol 35 (1) ◽  
pp. 25-30 ◽  
Author(s):  
C. H. Coles ◽  
E. R. Waygood
Keyword(s):  
Carbon Dioxide ◽  
Malic Acid ◽  
Enzyme Purification ◽  
Acid Metabolism ◽  
Ammonia Solution ◽  
High Concentration ◽  
A New Technique ◽  
Succulent Plants ◽  
Short Days

The extraction of enzymes concerned with malic acid metabolism from succulent plants, notably Bryophyllum calycinum, has been made possible by the introduction of a new technique. The high concentration of organic acids in the vacuoles of leaf cells was neutralized in situ by vacuum infiltration with ammonia solution. Thus, during maceration, the enzyme proteins are neither precipitated nor inactivated and conventional methods of enzyme purification may be applied. Further experiments have shown that whereas B. calycinum plants may lose their ability to fix carbon dioxide actively in the dark following exposure to short days ([Formula: see text] hours) the enzymes involved in malic acid metabolism and carbon dioxide fixation in the dark are not necessarily depleted.

scholarly journals Key Process Conditions for Production of C4 Dicarboxylic Acids in Bioreactor Batch Cultures of an Engineered Saccharomyces cerevisiae Strain

2009 ◽  
Vol 76 (3) ◽  
pp. 744-750 ◽  
Author(s):  
Rintze M. Zelle ◽  
Erik de Hulster ◽  
Wendy Kloezen ◽  
Jack T. Pronk ◽  
Antonius J. A. van Maris
Keyword(s):  
Carbon Dioxide ◽  
Saccharomyces Cerevisiae ◽  
Process Parameters ◽  
Malic Acid ◽  
Acid Production ◽  
Shake Flask ◽  
Simultaneous Optimization ◽  
Process Conditions ◽  
Recent Effort ◽  
Shake Flasks

ABSTRACT A recent effort to improve malic acid production by Saccharomyces cerevisiae by means of metabolic engineering resulted in a strain that produced up to 59 g liter−1 of malate at a yield of 0.42 mol (mol glucose)−1 in calcium carbonate-buffered shake flask cultures. With shake flasks, process parameters that are important for scaling up this process cannot be controlled independently. In this study, growth and product formation by the engineered strain were studied in bioreactors in order to separately analyze the effects of pH, calcium, and carbon dioxide and oxygen availability. A near-neutral pH, which in shake flasks was achieved by adding CaCO3, was required for efficient C4 dicarboxylic acid production. Increased calcium concentrations, a side effect of CaCO3 dissolution, had a small positive effect on malate formation. Carbon dioxide enrichment of the sparging gas (up to 15% [vol/vol]) improved production of both malate and succinate. At higher concentrations, succinate titers further increased, reaching 0.29 mol (mol glucose)−1, whereas malate formation strongly decreased. Although fully aerobic conditions could be achieved, it was found that moderate oxygen limitation benefitted malate production. In conclusion, malic acid production with the engineered S. cerevisiae strain could be successfully transferred from shake flasks to 1-liter batch bioreactors by simultaneous optimization of four process parameters (pH and concentrations of CO2, calcium, and O2). Under optimized conditions, a malate yield of 0.48 ± 0.01 mol (mol glucose)−1 was obtained in bioreactors, a 19% increase over yields in shake flask experiments.

scholarly journals Uptake and Conversion of Radioactive Carbon Dioxide and Glucose in the Acerola and their Relationship to Ascorbic Acid Biosynthesis

1969 ◽  
Vol 50 (1) ◽  
pp. 1-9
Author(s):  
A. Maretzki ◽  
H. J. Teas ◽  
C. F. Asenjo
Keyword(s):  
Carbon Dioxide ◽  
Amino Acids ◽  
Ascorbic Acid ◽  
Malic Acid ◽  
West Indian ◽  
Acid Biosynthesis ◽  
Radioactive Carbon ◽  
Ascorbic Acid Biosynthesis

A study of the fate of radiocarbon-labeled glucose and carbon dioxide in the acerola (West Indian Cherry) has shown that these substances follow patterns of conversion comparable to those observed in other plants. These substances were not preferentially incorporated into ascorbic acid by acerola fruit. Sucrose, several amino acids, and malic acid appear to compete successfully with ascorbic acid for the label from these precursors.

Malic Acid as a Source of Carbon Dioxide in Cucumber Juice Fermentations

1982 ◽  
Vol 47 (6) ◽  
pp. 1862-1865 ◽  
Author(s):  
R. F. McFEETERS ◽  
H. P. FLEMING ◽  
R. L. THOMPSON
Keyword(s):  
Carbon Dioxide ◽  
Malic Acid

Electron Cytochemical Study of Carbon Dioxide Laser Effect on Rhesus Monkey Cornea

1974 ◽  
Vol 32 ◽  
pp. 224-225
Author(s):  
K. C. Tsou ◽  
J. Morris ◽  
P. Shawaluk ◽  
B. Stuck ◽  
E. Beatrice
Keyword(s):  
Carbon Dioxide ◽  
Electron Microscope ◽  
Rhesus Monkey ◽  
Carbon Dioxide Laser ◽  
Cytochemical Study ◽  
Laser Effect

While much is known regarding the effect of lasers on the retina, little study has been done on the effect of lasers on cornea, because of the limitation of the size of the material. Using a combination of electron microscope and several newly developed cytochemical methods, the effect of laser can now be studied on eye for the purpose of correlating functional and morphological damage. The present paper illustrates such study with CO2 laser on Rhesus monkey.

The Critical Point Drying Method Applied to Scanning Electron Microscopy of L-929 Cells

1970 ◽  
Vol 28 ◽  
pp. 278-279
Author(s):  
Charles TurnbiLL ◽  
Delbert E. Philpott
Keyword(s):  
Electron Microscopy ◽  
Carbon Dioxide ◽  
Surface Tension ◽  
Critical Point ◽  
Freeze Drying ◽  
Attractive Alternative ◽  
Crystal Formation ◽  
Critical Point Drying ◽  
Time Required ◽  
Scanning Electron

The advent of the scanning electron microscope (SCEM) has renewed interest in preparing specimens by avoiding the forces of surface tension. The present method of freeze drying by Boyde and Barger (1969) and Small and Marszalek (1969) does prevent surface tension but ice crystal formation and time required for pumping out the specimen to dryness has discouraged us. We believe an attractive alternative to freeze drying is the critical point method originated by Anderson (1951; for electron microscopy. He avoided surface tension effects during drying by first exchanging the specimen water with alcohol, amy L acetate and then with carbon dioxide. He then selected a specific temperature (36.5°C) and pressure (72 Atm.) at which carbon dioxide would pass from the liquid to the gaseous phase without the effect of surface tension This combination of temperature and, pressure is known as the "critical point" of the Liquid.

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