This study was designed to analyse the antioxidant capacity of lactic acid bacteria (LAB) in order to provide characteristic parameters and theoretical basis for its further utilization as a natural antioxidant. Further experiment was carried out to study its protection mechanism through oxidative stress Caco-2 cell model in vitro. For this purpose, antioxidative activity of cells and different...

Oxygen radicals are known to be produced by the cerebral vasculature during acute, pressor-induced hypertension and are also known to inactivate endothelium-derived relaxing factor. The objective of our present study was to determine if the oxygen radical scavenger superoxide dismutase (24,000 units/kg plus 1,600 units/kg/min) alters the pressor, cerebral blood flow, and mortality responses to ...

Reactive oxygen species comprise oxygen-based free radicals and non-radical such as peroxynitrite electronically excited (singlet) oxygen. These reactive often have short lifetimes, much of our understanding their formation reactivity in biological especially medical environments has come from complimentary fast reaction methods involving pulsed lasers high-energy radiation techniques. related ...

Thiyl radicals are formed from one-electron oxidation of thiols. Thiyl radicals participate in a number of reactions including electron transfer, hydrogen abstraction and addition reactions with several biological constituents and xenobiotics. Thiyl radicals can be detected by optical spectroscopy or by electron spin resonance (ESR) spectroscopy. Thiyl radicals appear to play a role in the nitr...

Diminished amounts of manganese-containing superoxide dismutase have been found in all the tumors examined to date. Lowered amounts of the copper-zinc-containing superoxide dismutase have been found in many, but not all, tumors. At the same time, tumors have been shown to produce superoxide radicals. It is shown how diminished enzyme activities along with radical production may lead to many of ...

Superoxide radicals are produced in trace amounts by the mitochondrial respiratory chain. Most are removed rapidly by superoxide dismutase in the matrix. Superoxide is also known to react with glutathione. Reported values of the rate constant for this reaction range from 10(2) to in excess of 10(5) M(-1).s(-1). The magnitude of this rate constant has important physiological implications because...

Superoxide dismutase is antioxidant enzyme responsible for the quenching of superoxide radicals which are released during the chemical reactions of the various metabolic pathways. It is a non-heme protein. Different iso-enzymes of superoxide dismutase are described. The mitochondrial enzyme is manganese dependent, cytoplasmic enzyme is copper-zinc dependent. These enzymes are evenly and ubiquit...

PURPOSE This study was designed to evaluate the relationship among free radicals and vascular endothelial growth factor (VEGF) and inducible nitric oxide synthase (iNOS) during the progression of left ventricular hypertrophy (LVH) in pressure-overload rat heart. METHODS Hypertrophied rat heart created by abdominal aortic banding at the age of 4 weeks was studied at the ages of 14, 15, 18, 21,...

Hydrogen peroxide, superoxide radical, and hydroxyl radical were all formed during the autoxidation of four cytotoxic agents, namely, 6-hydroxydopamine, 6-aminodopamine, 6,7-dihydroxytryptamine, and dialuric acid. Ascorbic acid and 5-hydroxydopamine, two autoxidizable agents of biological interest but without similar cytotoxic actions, were used as negative controls. The results tend to implica...