Potent Antioxidant and Genoprotective Effects of Boeravinone G, a Rotenoid Isolated from Boerhaavia diffusa

Background and Aims: Free radicals are implicated in the aetiology of some gastrointestinal disorders such as gastric ulcer, colorectal cancer and inflammatory bowel disease. In the present study we investigated the antioxidant and genoprotective activity of some rotenoids (i.e. boeravinones) isolated from the roots of Boerhaavia diffusa, a plant used in the Ayurvedic medicine for the treatment of diseases affecting the gastrointestinal tract. Methods/Principal Findings: Antioxidant activity has been evaluated using both chemical (Electron Spin Resonance spectroscopy, ESR) and Caco-2 cells-based (TBARS and ROS) assays. DNA damage was evaluated by Comet assay, while pERK 1/2 and phospho-NF-kB p65 levels were estimated by western blot. Boeravinones G, D and H significantly reduced the signal intensity of ESR induced by hydroxyl radicals, suggesting a scavenging activity. Among rotenoids tested, boeravinone G exerted the most potent effect. Boeravinone G inhibited both TBARS and ROS formation induced by Fenton's reagent, increased SOD activity and reduced H 2O 2-induced DNA damage. Finally, boeravinone G reduced the levels of pERK 1 and phospho-NF-kB p65 (but not of pERK 2) increased by Fenton's reagent. Conclusions: It is concluded that boeravinone G exhibits an extraordinary potent antioxidant activity (significant effect in the nanomolar range). The MAP kinase and NF-kB pathways seem to be involved in the antioxidant effect of boeravinone G. Boeravinone G might be considered as lead compound for the development of drugs potentially useful against those pathologies whose aetiology is related to ROS-mediated injuries

Isolation and Identification of a Novel Antioxidant with Antitumour Activity from Serratia ureilytica Using Squid Pen as Fermentation Substrate

[[abstract]]The antioxidant activity of the culture supernatant of Serratia ureilytica TKU013 with squid pen as the sole carbon/nitrogen source was assessed by three methods, and the phenolic contents were assayed. The supernatant with the highest antioxidant activity was further purified by liquid–liquid partition, revealing the ethyl acetate extract exhibited the strongest antioxidant activity and the highest total phenolic content. Eight fractions were retrieved from silica gel column chromatography of this extract, designated F1–F8. F4 was found to possess the strong antioxidative activity and the highest total phenolic content and also exhibited strong cytotoxic activities against two different tumoural cell lines. A new compound (Serranticin) with antioxidant and antitumor activity was obtained from F4. The structure of Serranticin is analogous to that of siderophores (hexacoordinated catecholamine), which are iron chelators. As such, Serranticin has the potential for use as a deferration agent in various iron overload diseases.[[notice]]補正完畢[[journaltype]]國外[[incitationindex]]SCI[[ispeerreviewed]]Y[[booktype]]紙本[[countrycodes]]US

Evaluation of antioxidant and cytoprotective activities of <it>Arnica montana</it> L. and <it>Artemisia absinthium</it> L. ethanolic extracts

<p>Abstract</p> <p>Background</p> <p><it>Arnica montana</it> L. and <it>Artemisia absinthium</it> L. (Asteraceae) are medicinal plants native to temperate regions of Europe, including Romania, traditionally used for treatment of skin wounds, bruises and contusions. In the present study, <it>A. montana</it> and <it>A. absinthium</it> ethanolic extracts were evaluated for their chemical composition, antioxidant activity and protective effect against H₂O₂-induced oxidative stress in a mouse fibroblast-like NCTC cell line.</p> <p>Results</p> <p><it>A. absinthium</it> extract showed a higher antioxidant capacity than <it>A. montana</it> extract as Trolox equivalent antioxidant capacity, Oxygen radical absorbance capacity and 2,2-diphenyl-1-picrylhydrazyl free radical-scavenging activity, in correlation with its flavonoids and phenolic acids content. Both plant extracts had significant effects on the growth of NCTC cells in the range of 10–100 mg/L <it>A. montana</it> and 10–500 mg/L <it>A. absinthium</it>. They also protected fibroblast cells against hydrogen peroxide-induced oxidative damage, at the same doses. The best protection was observed in cell pre-treatment with 10 mg/L <it>A. montana</it> and 10–300 mg/L <it>A. absinthium</it>, respectively, as determined by Neutral red and lactate dehydrogenase assays. In addition, cell pre-treatment with plant extracts, at these concentrations, prevented morphological changes induced by hydrogen peroxide. Flow-cytometry analysis showed that pre-treatment with <it>A. montana</it> and <it>A. absinthium</it> extracts restored the proportion of cells in each phase of the cell cycle.</p> <p>Conclusions</p> <p><it>A. montana</it> and <it>A. absinthium</it> extracts, rich in flavonoids and phenolic acids, showed a good antioxidant activity and cytoprotective effect against oxidative damage in fibroblast-like cells. These results provide scientific support for the traditional use of <it>A. montana</it> and <it>A. absinthium</it> in treatment of skin disorders.</p