Free radical scavenging

This thesis documents a research program in which Australian grown Danshen extracts and related bioactive compounds have been demonstrated to be effective in scavenging free radicals, namely ROS generation, in a cell free system and NADPH oxidase derived superoxide (O2-) generation in vascular tissue (rat aorta). Danshen extracts, both aqueous and ethanol, and their active compounds (Tanshinone IIA, Salvianolic Acid B and Danshensu) demonstrated anti-oxidant activity however findings exhibited stronger activity in a cell free system than in the aortic vascular tissue.

138p runthenight07 01-03-2023 9 3   Download

The diversity of medicinal plants in Vietnam is a rich source to develop novel health products. In this study, the antioxidant and antimicrobial activities of ethanolic extracts of Pluchea indica, Drynaria fortunei, Stephania glabra, lemongrass (Cymbopogon citratus) and lime (Citrus aurantifolia) mixture, and ginger (Zingiber officinale) and kumquat (Citrus japonica) mixture, were evaluated.

7p guitaracoustic02 08-12-2021 13 1   Download

In this study, methanolic extracts from the stems, leaves and flowers of Ipomoea pes-caprae that were collected in Xuan Thuy National Park were evaluated for their antibacterial and antioxidative activities, and their ability to inhibit plant growth. The DPPH free radical scavenging activity of crude methanol extracts was evaluated.

7p tamynhan8 04-11-2020 20 2   Download

This fraction showed the highest antioxidant activity by dose-dependent free radical scavenging action (IC50 69.50 ± 1.55 µg/mL). R. tomentosa leaf extracts, especially the n-hexane fraction, also exhibited strong antimicrobial activity against Gram-negative and Gram-positive bacteria and fungi as well as moderate inhibitory effect on L-DOPA (L-3,4-dihydroxyphenylalanine) oxidase activity of tyrosinase in the melanin biosynthesis pathway.

9p tamynhan8 04-11-2020 13 1   Download

Colloidal silver nanoparticles were synthesized by
Co-60 ray irradiation of Ag+ in aqueous solution containing polyvinyl alcohol (PVA) as stabilizer and 0.5 M ethyl alcohol as free radical (OH• ) scavenger. The effect of Ag+ concentration which varied from 1 to 50 mM on the saturated conversion dose (D) of Ag+ into Ag determined by UV-vis spectroscopy and the size of Ag nanoparticles characterized by transmission electron microscopy (TEM) were investigated. The dependence of D (kGy) and average size (d, nm) of Ag nanoparticles on Ag+ concentration was found out to be as: D (kGy) = 0.

5p uocvong03 24-09-2015 36 4   Download

Metformin (1,1-dimethylbiguanide) is an antihyperglycae-mic drug used to normalize glucose concentrations in type 2 diabetes. Furthermore, antioxidant benefits have been reported in diabetic patients treated with metformin. This work was aimed at studying the scavenging capacity of this drug against reactive oxygen species (ROS) like Æ OH and O Æ
2 -free radicals. ROS were produced by gamma radio-lysis of water. The irradiated solutions of metformin were analyzed by UV/visible absorption spectrophotometry.

8p awards 05-04-2013 60 1   Download

Galloylated and nongalloylated catechin conjugates with cysteine deriva-tives have been synthesized and evaluated for their capacity to scavenge free radicals and to influence crucial functions (cell cycle, apoptosis) in HT29 colon carcinoma cells. We show that the nonphenolic part of the molecule modified the capacity of catechins to donate hydrogen atoms and to transfer electrons to free radicals.

12p inspiron33 26-03-2013 34 4   Download

Pycnogenol  , which is extracted from the bark of French maritime pine, has been shown to have antioxidant and free radical scavenging activities. Thioredoxin reductase (TrxR), glutathione peroxidase (GPx) and glutathi-one reductase (GR) are three central redox enzymes that are active in endogenous defence against oxidative stress in the cell.

9p vinaphone15 27-02-2013 42 2   Download

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Free radical scavenging activity and lipoxygenase inhibition of Mahonia aquifolium extract and isoquinoline alkaloids,,,

7p thulanh27 13-12-2011 60 2   Download

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Wertheim cung cấp cho các bạn kiến thức về ngành y đề tài: Beneficial effect of the oxygen free radical scavenger amifostine (WR-2721) on spinal cord ischemia/reperfusion injury in rabbits...

12p thulanh24 21-11-2011 56 3   Download