The natural product jadomycin B, isolated from Streptomyces venezeulae ISP5230, has been found to cleave DNA in the presence of Cu(II) ions without the requirement for an external reducing agent. The efficiency of DNA cleavage was probed using supercoiled plasmid DNA in buffered solution as a model environment. EC₅₀ and t(½) values for cleavage were 1.7 μM and 0.75 h, respectively, and varied ±...

Reactive oxygen species (ROS) are generated constantly in vivo. They can lead to lipid peroxidation and oxidation of some enzymes, as well as protein oxidation and degradation. Cells possess several biological systems, defined as 'scavengers', to protect themselves from the radical-mediated damage. Immune cells may discharge their arsenal of toxic agents against host tissues, resulting in oxida...

The aim of this study was to determine the in vitro antioxidant activity, free radical scavenging property and the beneficial effects of extracts of various parts of Syzygium guineense in reducing oxidative stress damage in the liver. The effects of extracts on free radicals were determined on radicals DPPH, ABTS, NO and OH followed by the antioxidant properties using Ferric Reducing Antioxidan...

Granulocytes collected by reversible adhesion to nylon wool fiber (NWF) function relatively well in standard in vitro tests; however, they have an abnormally shortened survival time in the circulation. Assuming that this rapid disappearance represents clearance and that recognition by phagocytes is important for such clearance, we used an autologous in vitro cell:cell recognition assay to deter...

In this study, ZnO nanoparticles fixed on glass plates were employed as photocatalysts for the degradation of Acid Red 88 (AR88) dye in aquatic solution. ZnO nanoparticles were synthesized through coprecipitation method and fixed on glass plates. X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques were used for characterization of nanoparticle samples. A batch reactor equi...

Activation of leukocytes results in the release of a variety of vasoactive substances that may modulate vascular tone. We studied the effect of human polymorphonuclear (PMN) and mononuclear (MONO) leukocytes on quiescent femoral arteries in vitro. Arteries were obtained from normal and atherosclerotic cynomolgus monkeys. In normal arteries, stimulation of PMNs (3 and 5 x 10(6) cells/ml) with ei...

Page no. 65 Sir, Free radicals in systemic circulation lead to several forms of diseases involving cardiovascular, cerebrovascular, and respiratory system. They are highly unstable compounds which lead to oxidative damage to cellular lipids, protein, and DNA. A lot of research has been done to investigate the role of free radicals in several diseases.[1] This has led to the development of free ...

Plant biophenols have been shown to be effective in the modulation of Alzheimer's disease (AD) pathology resulting from free radical-induced oxidative stress and imbalance of the redox chemistry of transition metal ions (e.g., iron and copper). On the basis of earlier reported pharmacological activities, olive biophenols would also be expected to have anti-Alzheimer's activity. In the present s...

Antioxidant activity of Berry (Morus alba var. nigra) was investigated. For superoxide anion radical assay, the superoxide anion radicals were generated by a pyrogallol auto oxidation system, Nitric oxide radical inhibition by the use of Griess Illosvoy reaction and reducing power was determined according to the Oyaizu method. At least this sample was represented a potential antioxidant capacit...