Search results for "redox"

Effect of Ti(IY) on some indicators of physiological activity inCapsicum annuum, L.

1994

SummaryPaprika pepper (Capsicum annuum, L., cv. Negral) plants grown in a greenhouse were supplied Ti(IV) ascorbate through the roots or through leaves. Biomass production, peroxidase (donor: H2O, oxidoreductase; EC 1.11.1.7) activity, and malic acid, starch and chlorophyll concentrations were determined in different plant organs. It was observed that Ti increased the concentration of some of the metabolites studied and promoted both peroxidase activity and biomass production. The profitable effect of the Ti treatments could occur because they enhance the availability of other nutrients. This effect could be due to the low redox potential of the Ti+3/Ti+4 system that catalyzes the activity …

A Photoredox-Catalyzed Four Component Reaction for the Atom-Efficient Synthesis of Complex Secondary Amines

2020

The one-pot sulfonylation/aminoalkylation of styrene derivatives furnishing highly substituted gamma-sulfonylamines was accomplished through a photoredox-catalyzed four-component reaction. Apart from one molecule of water and the sodium counterion of the sulfinate, all atoms of the starting materials are transferred to the final product, rendering this process highly atom-efficient. The operationally simple protocol allows for the simultaneous formation of three new single bonds (C–S, C–N, and C–C) and therefore grants rapid access to structurally diverse products. The reaction proceeds under mild conditions in aqueous acetonitrile and shows a broad scope, including natural products and dru…

Relationship between Auxin-Dependent Proton Extrusion and Plasmalemma Redox System in Maize Coleoptile Segments

1988

Abraded coleoptile segments reduce ferricyanide utilizing endogenous substrates. The kinetics of ferricyanide reduction shows an initial rapid rate followed by a slow rate of reduction. The duration of the initial phase is about 5 minutes. The slow phase is observed for more than 30 minutes. A Lineweaver-Burk plot of the slow phase was linear and revealed maximum velocity of the reaction of 42 nmols ferricyanide reduced/hour*coleoptile segment and an apparent Km (ferri) of 2.25mM.

Über polymerisationen mit hilfe von redox-systemen

1951

Bei der durch Eisen-Redox-Systeme ausgelosten Polymerisation von Styrol und von Dimethylbutadien -2.3 wird die peroxydische Komponente (Diacylperoxyd) in die Makromolekule eingebaut. Es wird gezeigt, das bei der Polymerisation des Styrols mit Dibrombenzoylperoxyd-Eisenbenzoat-Benzoin die Zahl der eingebauten, markierten Endgruppen die gleiche ist wie bei der peroxydischen Polymerisation mit Di-Brombenzoylperoxyd. Dies spricht dafur, das auch die peroxydische Polymerisation durch Radikale ausgelost wird, die bei einer Redox-Reaktion zwischen Peroxyd und Monomerem entstehen. Fur das polymere Dimethylbutadien wurde nachgewiesen, das alle markierten Endgruppen, die bei der eisen-redox-katalysie…

Redox and Photochemistry of Bis(terpyridine)ruthenium(II) Amino Acids and Their Amide Conjugates – from Understanding to Applications (Eur. J. Inorg.…

2014

Early reductive stress followed by a late onset oxidative stress in acute myocardial infarction

2018

Introduction The idea that the cells might suffer from reductive rather than oxidative stress and that such stress may be relevant in pathophysiology has gained momentum. Aim We aimed at studying markers of oxidative stress and damage as well as the expression of antioxidant enzymes in a swine model of acute myocardial infarction (AMI) followed by reperfusion. Results and Discussion We found an increase in the GSH to GSSG ratio, a decrease in protein glutathionylation and a decrease in p38 MAPK phosphorylation after 90 minutes of ischaemia in heart samples. It was accompanied by an increase in the expression of Thioredoxin (TrX) and Peroxiredoxin (PrX) and a decrease in the expression of Gl…

Electrochemical reduction of the nitrite to ammonium ions in presence of [MoO2(O2CC(S)C6H5)2]2−

1995

Abstract Ammonia is formed during potentiostatic reduction of sodium nitrite solutions on the nafion-complex-coated electrode. When (NH4)2[MoO2(O2CC(S)(C6H5)2)2] is present in NaNO2 solutions a polarographic wave is associated to electrocatalytic reduction of nitrite ion. The wave height varies linearly on the concentration of nitrite ion, allowing a procedure for analysing this ion. This electrochemical behaviour distinguishes the nitrite from the nitrate ions. The Mo(VI), Mo(V), and Mo(IV) are involved in catalytic redox processes determining formation of NH4+ from nitrite ions.

Cellular redox status by alternariol in caco-2 cells

2013

Epigenetics and role of glutathione in redox regulation

2012

A new type of pi-electron donors with one dithiole unit: Substituted 7-(1,3-dithiol-2-ylidene)-7-hydrobenz[d,e]anthracenes

1999

New electron donors 11a–c bearing only one 1,3-dithiole ring conjugated with an acene backbone have been synthesized by Wittig–Horner reactions from 7H-benz[d,e]anthracen-7-one (10) and differently substituted phosphonate esters 9a–c. The donor properties of 11 have been characterized by means of both experimental techniques and quantum chemical calculations. Cyclic voltammetry measurements on the novel compounds predict donor abilities comparable to those of TTF and BEDT-TTF. The voltammograms show a multi-stage redox behaviour with oxidation up to the trication, where the first two oxidation processes take place at very close potentials. These processes have been assigned to a simultaneou…