INHIBITION OF CATALASE BY CARBOXYLIC ACIDS RELATED TO DISSOCIATION AND ASSOCIATION OF THE APOPROTEIN

1962 ◽  
Vol 40 (1) ◽  
pp. 1327-1334 ◽  
Author(s):  
Michio Itoh ◽  
Yasuharu Nakamura ◽  
Kazuo Shibata
Keyword(s):  
Absorption Spectrum ◽  
Formic Acid ◽  
Carboxylic Acids ◽  
Free Acid ◽  
Second Step ◽  
Benzoic Acids ◽  
Reagent Concentration ◽  
Inhibitory Effects ◽  
Different Types ◽  
Aliphatic Carboxylic Acids

The inhibitory effects of aliphatic and aromatic carboxylic acids (formic, acetic, propionic, butyric, benzoic, and salicylic acids) on catalase at pH 7.0 were studied by measuring the catalatic activity as a function of reagent concentration, and the results were correlated with the data obtained simultaneously by spectroscopic and ultracentrifugal analyses. The inhibition by salicylic and benzoic acids proceeds in two steps. In the first step, the activity drops to a certain level, and the sedimentation peak of the native catalase is unaltered. The second step of inhibition is accompanied by the dissociation of the catalase molecule into subunits, and the absorption spectrum is changed greatly. The inhibition by the aliphatic carboxylic acids except formic acid proceeds also in two steps in which the second step of inhibition is accompanied by the association of the catalase molecules. The inhibition by formic acid obeys the mechanism of the combination between heme and the free acid rather than its anion. These different types of inhibitions at neutral pH are discussed in relation to the data obtained previously at acidic pH's.

INHIBITION OF CATALASE BY CARBOXYLIC ACIDS RELATED TO DISSOCIATION AND ASSOCIATION OF THE APOPROTEIN

1962 ◽  
Vol 40 (10) ◽  
pp. 1327-1334 ◽  
Author(s):  
Michio Itoh ◽  
Yasuharu Nakamura ◽  
Kazuo Shibata
Keyword(s):  
Absorption Spectrum ◽  
Formic Acid ◽  
Carboxylic Acids ◽  
Free Acid ◽  
Second Step ◽  
Benzoic Acids ◽  
Reagent Concentration ◽  
Inhibitory Effects ◽  
Different Types ◽  
Aliphatic Carboxylic Acids

The inhibitory effects of aliphatic and aromatic carboxylic acids (formic, acetic, propionic, butyric, benzoic, and salicylic acids) on catalase at pH 7.0 were studied by measuring the catalatic activity as a function of reagent concentration, and the results were correlated with the data obtained simultaneously by spectroscopic and ultracentrifugal analyses. The inhibition by salicylic and benzoic acids proceeds in two steps. In the first step, the activity drops to a certain level, and the sedimentation peak of the native catalase is unaltered. The second step of inhibition is accompanied by the dissociation of the catalase molecule into subunits, and the absorption spectrum is changed greatly. The inhibition by the aliphatic carboxylic acids except formic acid proceeds also in two steps in which the second step of inhibition is accompanied by the association of the catalase molecules. The inhibition by formic acid obeys the mechanism of the combination between heme and the free acid rather than its anion. These different types of inhibitions at neutral pH are discussed in relation to the data obtained previously at acidic pH's.

Formation of Aliphatic Carboxylic Acids during Soda-AQ Pulping of Kenaf Bark

Holzforschung ◽  
2002 ◽  
Vol 56 (4) ◽  
pp. 388-394 ◽  
Author(s):  
Z. Feng ◽  
R. Alén ◽  
K. Niemelä
Keyword(s):  
Acetic Acid ◽  
Formic Acid ◽  
Carboxylic Acids ◽  
Dicarboxylic Acids ◽  
Hydroxy Acids ◽  
Hydroxy Carboxylic Acids ◽  
Aliphatic Carboxylic Acids ◽  
Cooking Conditions ◽  
Acetic Acids

Summary The formation of aliphatic carboxylic acids during soda-AQ pulping of kenaf bark was studied. In addition to formic and acetic acids, a variety of hydroxy monocarboxylic and dicarboxylic acids were monitored. The results showed that the formation of hydroxy acids and formic acid significantly depend, in contrast to acetic acid, on the cooking conditions employed. Detailed gas chromatographic studies revealed that the most abundant hydroxy carboxylic acids were glucoisosaccharinic, lactic, glycolic, 3-deoxypentonic, 2-hydroxybutanoic, xyloisosaccharinic, 3,4-dideoxypentonic, 2-hydroxyglutaric, and glucoisosaccharinaric acids. The total amount of aliphatic carboxylic acids corresponded to 12–16% of o.d. kenaf bark.

Generation of Phosphoranyl Radicals via Photoredox Catalysis Enables Voltage–Independent Activation of Strong C–O Bonds

2018 ◽  
Author(s):  
Erin Stache ◽  
Alyssa B. Ertel ◽  
Tomislav Rovis ◽  
Abigail G. Doyle
Keyword(s):  
Carboxylic Acids ◽  
Functional Groups ◽  
Single Step ◽  
Direct Access ◽  
Photoredox Catalysis ◽  
Acyl Radical ◽  
Synthetic Strategy ◽  
Acyl Radicals ◽  
Benzyl Radicals ◽  
Aliphatic Carboxylic Acids

Alcohols and carboxylic acids are ubiquitous functional groups found in organic molecules that could serve as radical precursors, but C–O bonds remain difficult to activate. We report a synthetic strategy for direct access to both alkyl and acyl radicals from these ubiquitous functional groups via photoredox catalysis. This method exploits the unique reactivity of phosphoranyl radicals, generated from a polar/SET crossover between a phosphine radical cation and an oxygen centered nucleophile. We first show the desired reactivity in the reduction of benzylic alcohols to the corresponding benzyl radicals with terminal H-atom trapping to afford the deoxygenated product. Using the same method, we demonstrate access to synthetically versatile acyl radicals which enables the reduction of aromatic and aliphatic carboxylic acids to the corresponding aldehydes with exceptional chemoselectivity. This protocol also transforms carboxylic acids to heterocycles and cyclic ketones via intramolecular acyl radical cyclizations to forge new C–O, C–N and C–C bonds in a single step.

Improved QSAR Analysis of the Toxicity of Aliphatic Carboxylic Acids

2003 ◽  
Vol 73 (11) ◽  
pp. 1792-1798 ◽  
Author(s):  
F. P. Maguna ◽  
M. B. Ninez ◽  
N. B. Okulik ◽  
E. A. Castro
Keyword(s):  
Carboxylic Acids ◽  
Qsar Analysis ◽  
Aliphatic Carboxylic Acids

Radical addition to acrylonitrile via catalytic photochemical decarboxylation of aliphatic carboxylic acids

2013 ◽  
Vol 54 (32) ◽  
pp. 4324-4326 ◽  
Author(s):  
Yasuharu Yoshimi ◽  
Sonoka Washida ◽  
Yoshiki Okita ◽  
Keisuke Nishikawa ◽  
Kousuke Maeda ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Radical Addition ◽  
Aliphatic Carboxylic Acids

Syntheses, structures, and properties of multidimensional lithium coordination polymers based on aliphatic carboxylic acids

2013 ◽  
Vol 42 (8) ◽  
pp. 2765-2772 ◽  
Author(s):  
Pei-Chi Cheng ◽  
Wei-Cheng Lin ◽  
Feng-Shuen Tseng ◽  
Ching-Che Kao ◽  
Ting-Guang Chang ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Coordination Polymers ◽  
Structures And Properties ◽  
Aliphatic Carboxylic Acids
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