No abstract available.
Acute Lung Injury* ; Animals ; Hydroxyl Radical* ; Rats*

This study investigated the antioxidant activity of methanol (MeOH) and water extracts from roots of Cirsium japonicum in vitro. MeOH extract showed a stronger free radical scavenging activity than water extract. However, both of extracts showed a concentration dependent hydroxyl radical scavenging activity, reducing power and metal chelating ability. MeOH extract had greater phenolic and flavonoid contents than water extract. The antidiabetic activity of these two extracts was evaluated by the alpha-glucosidase inhibition assay. The water extract showed a considerable alpha-glucosidase inhibitory activity. To our knowledge, this may be the first time to report the antioxidant and antidiabetic activities in Cirsium japonicum roots.
alpha-Glucosidases ; Cirsium ; Hydroxyl Radical ; Methanol ; Phenol ; Water

No abstract available.
Animals ; Brain* ; Hydroxyl Radical* ; Hypothermia ; Rats* ; Reactive Oxygen Species

Our study focused on the antioxidant activities of Mosidae leaf ethanol extract (MLE) and included measurements of reducing power, total phenolic compounds, DPPH radical scavenging activity, and hydroxyl radical scavenging activity. In order to determine whether or not MLE evidences any chemopreventive activities, experimental lung metastasis was induced via the i.v. inoculation of colon26-M3.1 carcinoma cells into BALB/c mice. Additionally, we attempted to characterize any possible cytotoxic effects in murine normal splenocytes and tumor cells (B16-BL6 and colon26-M3.1). The total phenolic content and reducing capacity were measured at 39 mg/100 mL and 1.24, respectively, whereas the DPPH and hydroxyl radical scavenging activities of MLE were measured to be 88.89% and 22.10%, respectively. Prophylactic i.v. treatment with MLE resulted in a dose-dependent and significant inhibition of lung metastasis. Specifically, a MLE dose of 200 ug per mouse resulted in an 88.90% inhibition of lung metastasis. For the cytotoxicity assay, MLE doses up to 100 ug/mL were not shown to affect the growth of normal murine splenocytes. Additionally, the survival of normal cells was not affected at MLE doses below 500 ug/mL. However, MLE doses up to 500 ug/mL reduced the percentage of tumor cell growth for B16BL6 (67% alive) and colon26-M3.1 (62% alive) cells.
Animals ; Ethanol ; Hydroxyl Radical ; Lung ; Mice ; Neoplasm Metastasis ; Phenol

The aim of this study was to measure and compare polyphenol content, antioxidant, and anti-inflammatory activity of six halophytes (Limonium tetragonum, Suaeda glauca, Suaeda japonica, Salicornia europaea, Triglochin maritimum, and Sonchus brachyotus). Depending on the total polyphenol content, the plants were categorized into two groups: (1) a high total polyphenol content group that included L. tetragonum, S. brachyotus, and S. europaea, and, (2) a low total polyphenol content group consisting of S. glauca, T. maritima, and S. japonica. Antioxidant activity was evaluated using DPPH and hydroxyl radical scavenging assays, and by measuring ROS. Anti-inflammatory activity was evaluated by measuring NO and PGE₂. L. tetragonum and S. brachyotus, that have high polyphenol content, also showed strong antioxidant activity. In addition, L. tetragonum, S. brachyotus, and S. europaea showed good anti-inflammatory activity. Consequently, the total polyphenol content was thought to be related to antioxidant and anti-inflammatory activity. Therefore, S. brachyotus and L. tetragonum are good candidates for use in pharmaceuticals and functional foods.
Chenopodiaceae ; Functional Food ; Hydroxyl Radical ; Korea ; Salt-Tolerant Plants ; Sonchus

OBJECTIVE: To investigate the eliminating ability of catechin to eliminate O2-* and *OH. METHODS: The ability of catechin to clear away O2-* and *OH was respectively measured by faintness chemiluminescence and spin trapping assay. RESULTS: IC50 that catechin eliminated O2-* and *OH was 6.16, 0.59 g/mL respectively, and the eliminating ability of catechin was much stronger than that of the extract from liquorice, rosemary, grape pip, giant knotweed and ginkgo leaf. CONCLUSION Compared with several important natural plants of antioxidants, the eliminating ability of cathechin is the best.
Antioxidants ; pharmacology ; Catechin ; pharmacology ; Free Radical Scavengers ; pharmacology ; Hydroxyl Radical ; metabolism ; Luminescent Measurements ; Superoxides ; metabolism

A mathematical model, which represents the radio-chemical reactions in water, was developed to study the effect of the radio-chemical products on cell kiling. The five differential equations were solved using dose rate equation and cell survival as a function of dose was computed. The known chemical rate constants were taken from the literature and unknown constants were determined by curve fitting to an experimental data. Sensitivity studies were performed by varying the rate constants and showed that the yield of H-radical had little effect whereas the change in concentration of OH-radical and direct interaction resulted in significant change on cell survival. The sensitivity studies showed good agreement with the observed effects. In conclusion, we developed a mathematical model that could be used as a means for the estimation of radiation damage.
Cell Survival ; DNA/*chemistry ; Free Radicals/*chemistry ; Hydroxyl Radical/chemistry ; *Models, Molecular

No abstract available.
Erythrocyte Membrane* ; Erythrocytes* ; Hydroxyl Radical* ; Lipid Peroxidation* ; Macrophages, Alveolar* ; Mineral Fibers*

OBJECTIVETo investigate the kinetic rate constants ozone and hydroxyl radicals towards two groups of antimicrobials -sulfadiazine (SD) and sulfamethoxazole (SMX).

METHODSThe solute consumption method was used to detect the rate constants of ozone alone with sulfadiazine and sulfamethoxazole, and tertiary butanol was selected as a scavenging agent and pH was adjusted to 2.5 by adding orthophosphate buffers (OB); and the competition kinetics studying methodwith nitrobenzene as a reference was applied to measure the rate constants of hydroxyl radicals towards sulfadiazine and sulfamethoxazole, and pH was adjusted to 7.0 by adding OB.

RESULTSThe rate constants of SD and SMX with ozone alone were 261 mol(-1) · dm(3) · s(-1) and 303 mol(-1) · dm3 · s(-1) by calculating in low reaction system. The rate constants of hydroxyl radicals with SD and SMX were 2.2×1010 mol(-1) · dm(3) · s(-1) and 2.7×1010 mol(-1) · dm(3) · s(-1), respectively. Moreover, the rate constants of hydroxyl radicals with SMX were found to have increased from 3.6×109 mol(-1) · dm(3) · s(-1) to 2.8×1010 mol(-1) · dm(3) · s(-1) with pH value rising from 5.0 to 7.8.

CONCLUSIONSMX and SD are both refractory to ozone oxidation alone, and are liable to be degraded by hydroxyl radicals, and the rate constants of SMX with the hydroxyl radical slightly increases with pH rise.

Hydroxyl Radical ; chemistry ; Kinetics ; Ozone ; chemistry ; Sulfamethoxazole ; chemistry ; Sulfonamides ; chemistry ; Water ; chemistry

The free radicals generated during the ischemic/reperfusion period have been suggested as a possible cause for tissue damage in organs. This state was conducted to investigate protective effects of free radical scavengers through changes in the lipid peroxide content of the testis when administered before reperfusion of testicular torsion. These protective agents include superoxide dismutase(SOD), an oxygen radical scavenger and dimethylthiourea(DMTU), a hydroxyl radical scavenger. Forty five Sprague-Dawley rats were divided into 9 groups, each containing 5 rats. Group 1 served to determine basal values of the lipid peroxide content of the testis ; group 2 underwent sham operation as a control ; group 3 was subjected to unilateral testicular torsion lasting 3 hours; group 4, 5 were subjected to the detorsion lasting 1 hour and 2 hours following torsion for 3 hours; group 6, 7, 8, 9 were treated with SOD or DMTU before detorsion following torsion lasting 3 hours. The measurement of thiobarbituric acid reactive products of lipid peroxidation(TBAR) were employed to assess the extent of lipid peroxidation in testicular tissues. TBAR from sham operation control groups did not differ significantly from basal groups (p>0.05). Testicular torsion caused a significant increase in TBAR in the testis (p<0.05) when compared with basal values and detorsion caused a further significant increase when compared with values obtained after torsion. But TBAR after 1 hr detorsion did not change significantly compared with values obtained after 2 hours detorsion. The pretreatment with SOD prevented this further increase but the pretreatment with DMTU didn't. In conclusion, biochemically, reperfusion injury occurs in testis following detorsion after testicular torsion of 720 lasting 3 hours. The pretreatment with SOD, an oxygen radical scavenger, is effective in preventing reperfusion injury.
Animals ; Free Radical Scavengers* ; Free Radicals ; Hydroxyl Radical ; Lipid Peroxidation ; Oxygen ; Protective Agents ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury* ; Reperfusion* ; Spermatic Cord Torsion* ; Superoxides ; Testis