Oxygen inhibition

Mitochondria do three things oxidize substrates, consume oxygen, and make ATP. Uncouplers prevent the synthesis of ATP but do not inhibit oxygen consumption or substrate oxidation. Uncouplers work by destroying the pH gradient. The classic uncoupler is dinitrophenol (DNP). This phenol is a relatively strong acid and exists as the phenol and the phenolate anion. 

Quercetin and rutin suppressed photosensitized hemolysis of human erythrocytes with ho values equal to 40 p.mol l-1 and 150 jjlmt>I I 1, respectively [139]. Suppression of photohemolysis was accompanied by inhibition of lipid peroxidation. Morin inhibited oxygen radical-mediated damage induced by superoxide or peroxyl radicals to the human cells in the cardiovascular system, erythrocytes, ventricular myocytes, and saphenous vein endothelial cells [140]. Rutin protected against hemoglobin oxidation inside erythrocytes stimulated by prooxidant primaquine [141],... 

Thus, the mechanism of MT antioxidant activity might be connected with the possible antioxidant effect of zinc. Zinc is a nontransition metal and therefore, its participation in redox processes is not really expected. The simplest mechanism of zinc antioxidant activity is the competition with transition metal ions capable of initiating free radical-mediated processes. For example, it has recently been shown [342] that zinc inhibited copper- and iron-initiated liposomal peroxidation but had no effect on peroxidative processes initiated by free radicals and peroxynitrite. These findings contradict the earlier results obtained by Coassin et al. [343] who found no inhibitory effects of zinc on microsomal lipid peroxidation in contrast to the inhibitory effects of manganese and cobalt. Yeomans et al. [344] showed that the zinc-histidine complex is able to inhibit copper-induced LDL oxidation, but the antioxidant effect of this complex obviously depended on histidine and not zinc because zinc sulfate was ineffective. We proposed another mode of possible antioxidant effect of zinc [345], It has been found that Zn and Mg aspartates inhibited oxygen radical production by xanthine oxidase, NADPH oxidase, and human blood leukocytes. The antioxidant effect of these salts supposedly was a consequence of the acceleration of spontaneous superoxide dismutation due to increasing medium acidity. 

Cytochrome c oxidase (an enzyme in the mitochondrial respiratory chain) is sensitive to cyanide action (Way 1984). Due to its inhibition, oxygen cannot be utilized, histotoxic hypoxia develops, and this can lead to deaths of humans and animals (see Section 2.3.3). 

Azole compounds, poly-N-vinylimidazole (PVI-1) and 2-undecylimidazole (UDI), are studied as alternative inhibitors to benzotriazole (BTA) for copper corrosion in aqueous systems using electrochemical techniques. It is shown that UDI, either as a cast film or dissolved in solution at concentrations as low as 7 X inhibits oxygen reduction on... 

Azole compounds such as benzotriazole, benzimidazole, indazole and imidazoles are efficient anti-corrosion agents for copper and copper-base alloys [1-10]. Many experimental techniques [11-15] have been used to study the corrosion inhibition mechanisms, however, the mechanisms are still not well understood. It is believed that the complex formation between copper and nitrogen atoms would inhibit oxygen adsorption on copper surface [16-20]. 

In an in vitro study in an adipocyte cell line (3T3L1 cells), >75% of the 2,2, 4,4, 5,5 -hexabromobiphenyl taken up by the cells was associated with subcellular fractions that contained 85% of the cellular triglyceride, with only 20% of the compound found in the microsomal plasma-membrane fraction (Kraus and Bernstein 1986). This study also found that inhibition of respiration by cyanide at a concentration that completely inhibited oxygen consumption did not affect uptake of 2,2, 4,4, 5,5 -hexabromobiphenyl, supporting the assumption that because of their lipophilic nature, PBBs penetrate membranes by passive diffusion. 

Action of Ouabain on Kidney Tissue Ouabain specifically inhibits the Na+K+ ATPase activity of animal tissues but is not known to inhibit any other enzyme. When ouabain is added to thin slices of living kidney tissue, it inhibits oxygen consumption by 66%. Why What does this observation tell us about the use of respiratory energy by kidney tissue ... 

There is little published information of interest to carbohydrate chemists concerning the benzoic acid herbicides. The predominant member, 2,3,6-trichlorobenzoic acid, inhibited uptake and utilization109 of acetate-14C. It shows some auxin-like properties, whereas 2,3,5-triiodobenzoic acid appears to block the transport of natural and synthetic auxins, and has often been termed an antiauxin. The triiodo compound inhibited oxygen (86% at... 

Molten sodium borate or boric oxide (a low-melting glass) can cover and stabilize the unburned substrate/char and inhibit oxygen permeation. 

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