• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.11a
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• pp.64-64
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• 2003

It is thought that highly reactive oxygen radicals generated at the ischemia-reperfusion in case of strokes play an important role in damaging the brain. We examined the neuroprotective effects from the several medicinal herbs in the transient ischemic rat model and compared their effects with the free radical scavenging activities. Transient ischemia was induced by intraluminal occusion of the right middle cerebral artety for 120 min and reperfusion was continued for 22 h in rats. The free radical scavenging properties of medicinal herbs were examined in vitro by determination of the interaction with the 1,l-diphenyl-2-picrylhydrazyl (DPPH) stable free radical. Aqueous extracts of 11 medicinal herbs (200 mg/kg) were orally administered, promptly prior to reperfusion and 2 h after reperfusion. Total infarction volume in the ipsilateral hemisphere of ischemia reperfusion rats was significantly lowered by the treatment of 7 medicinal herbs (Sophora flavescens, Lycopus lucidus, Sanguisorba officinalis, Caesalpinia sappan, Albizia julibrissin, Rubia akane, Psoralea corylifolia, Prunella vulgaris). However, all of these medicinal herbs did not show antioxidative activities. These results suggest that neuroprotective effects of several drugs are not always correlated with their antioxidative properties.

• Biomolecules & Therapeutics
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• v.15 no.1
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• pp.46-51
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• 2007

Bioassay-directed chromatographic fractionation of an ethyl acetate extract from leaves of sweet potato (Ipomoea batatas L.) afforded six quinic acid derivatives: 3,5-epi-dicaffeoylquinic acid (1), 3,5-dicaffeoylquinic acid (2), methyl 3,5-O-dicaffeoylquinate (3), methyl 3,4-dicaffeoylquinate (4), methyl 4,5-dicaffeoylquinic acid (5),4,5-dicaffeoylquinate (6), and two phenolic compounds: caffeic acid (7) and caffeic acid methyl ester (8) together with three flavonoids: quercetin 3-O-${\beta}$-D-glucopyranoside (9), quercetin 3-O-${\beta}$-D-glucopyranoside, isoquercitrin (10) and kaempferol 3-O-${\beta}$-D-glucopyranoside (11). The structures of these compounds were elucidated by the aid of spectroscopic methods. These compounds were assessed for antioxidant activities using three different cell-free bioassay systems. All isolates except 11 showed potent DPPH and superoxide anion radicals scavenging, and lipid peroxidation inhibitory activities. 3,5-epi-DCQA (1) and methyl quinates (3-5) along with flavonoide 9 were isolated for the first time from this plant.

• Natural Product Sciences
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• v.17 no.4
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• pp.285-290
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• 2011

The rhizome of Alisma orientale Juzep (Alismataceae) has been used as a crude drug for diabetes, edema, inflammation and urinary disturbances in oriental medicine. Recent animal studies have shown that the extract of Alisma orientale rhizome (AOR) can potently lower high levels of serum lipids and improve insulin resistance, which are usually detected in patients and animals with non-alcoholic fatty liver disease. So, we studied the antioxidative effects of AOR extracts and fraction in vitro and their protective effects against acute hepatotoxicity induced by $CCl_4$ in vivo.. We then investigated the effects of each fraction on hepatotoxicity induced by tert-butyl hydroperoxide (t-BHP). DAOR (dichloromethane fraction of the Alisma orientale rhizome) scavenged free radicals and superoxide anions. DAOR protected against $CCl_4$ induced hepatotoxicity. DAOR had hepatoprotective and antioxidative effects against t-BHP-induced hepatotoxicity in HepG2 cells and in rats.

• Advances in Traditional Medicine
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• v.10 no.4
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• pp.271-277
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• 2010

We tested to determine if Mori Cortex Radicis extract has antioxidant activities and its potential mechanism of action was explored. Anti-oxidative effects were tested by measuring free radical and nitric Oxide (NO) scavenging activity, and reducing power. Since iNOS and COX-2 are important enzymes responsible for the production of free radicals in the cell, Mori Cortex Radicis extract was tested as to whether it could inhibit iNOS and COX-2 expression in LPS stimulated Raw cells. 70% methanolic extract of Mori Cortex Radicis exerted significant DPPH free radical and NO scavenging activities. In addition, the Mori Cortex Radicis extract exerted dramatic reducing power with maximal activity observed at 1 mg/ml (11-fold over control). Production of iNOS induced by LPS was significantly inhibited by the Mori Cortex Radicis extract, suggesting it could inhibit NO production by suppressing iNOS expression. COX-2 induced by LPS was also significantly inhibited by the Mori Cortex Radicis extract. The extract contains well known antioxidant components including phenolics, flavonoids and anthocyanin at the concentration of 0.23 mg/g, 42.97 mg/g and 12.08 mg/g, respectively. These results suggest that 70% methanolic extract of Mori Cortex Radicis exerts significant anti-oxidant activity via inhibiting iNOS and COX-2 induction.

• Journal of the Mineralogical Society of Korea
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• v.28 no.3
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• pp.245-253
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• 2015

The performance of $TiO_2$ photo-catalytic oxidation process is significantly dependent on the amount of hydroxyl radicals produced during the process, and it is an essential prerequisite to quantify its production. However, precise and accurate methods for quantification of hydroxyl radicals have not been developed so far. For this reason, this study was initiated to compare existing methods for analysis of hydroxyl radicals produced by $TiO_2$ photo-catalytic oxidation and to propose a new method to overcome the limitation of established methods. To simulate $TiO_2$ photo-catalytic oxidation process, Degussa P25 which has been widely used as a standard $TiO_2$ photo-catalyst was used with the dose of 0.05 g/L. The light source of process was UVC mercury low-pressure lamp (11 W, $2,975mW/cm^2$). The results indicate that both potassium iodide (KI)/UV-vis spectrometer and terephthalic acid (TPA)/fluorescence spectrometer methods could be applied to qualitatively measure hydroxyl radicals via detection of triiodide ion ($I_3{^-}$) and 2-hydroxyterephthalic acid which are produced by reactions of iodine ion ($I^-$) and TPA with hydroxyl radicals, respectively. However, it was possible to quantitatively measure hydroxyl radicals using TPA method coupled with high-performance liquid chromatograph (HPLC). The analytical results using TPA/HPLC method show that hydroxyl radical of 0.013 M was produced after 8 hours operation of photo-catalytic oxidation under specific experimental conditions of this study. The proposed method is expected to contribute to precise the evaluation of the performance of photo-catalytic oxidation process.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.46-51
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• 2008

The objective of this study was to investigate antioxidant activities of freeze-dried, main root, and fine root of ginseng (Panax ginseng CA. Meyer), which were extracted with various solvents including ethanol, methanol, and water. Ethanol extracts in both parts showed the most powerful scavenging activities against DPPH radicals. Especially, ethanol extract of fine root had higher reducing power and antioxidant capacity than that of main root. The highest antioxidant activity in linoleic acid emulsion system was also observed in fine root extracted with ethanol, followed by methanol and water. Both ferrous ion chelating activity and ferric reducing antioxidant power (FRAP) of extracts were increased with the increase of extracts concentration. These results suggest that ethanol extract of fine root of ginseng has the most effective antioxidant capacity compared to the methanol and water extracts tested in the present study. Thus it can be applied for the effective extraction of functional material from ginseng for the usage of pharmaceutical and/or food industries.

• Natural Product Sciences
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• v.9 no.4
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• pp.235-240
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• 2003

Tectorigenin has an apoptosis-inducing ability and immunosuppressive activity. We investigated the effect of tectorigenin on Phase I and II enzyme activities to elucidate the pharmacological action of the immunosuppressive tectorigenin in the diabetic rat. This compound was obtained from the hydrolysis of tetoridin isolated from the flower of Pueraria thumbergiana (Leguminosae). This crude drug (Puerariae Flos) has been used as a therapeutic for diabetes mellitus in traditional Korean medicine. Tecotrigenin inhibited the formation of malondialdehyde (MDA) and hydroxy radicals in serum and liver but promoted superoxide dismutase (SOD) activity. Low MDA contents and low xanthine oxidase and aldehyde oxidase activities were observed in the tectorigenin-treated rats, suggesting that such Phase I enzyme activities are the major source of lipid peroxidation. However, tectorigenin increased Phase II enzyme activities such as SOD, glutathione peroxidase and catalase, suggesting the activation of free radical-scavenging enzymes. The activities of tectorigenin were comparable to those of glibenclamide, which was employed as a positive control. These results suggest that tectorigenin may share some biological properties with glibenclamide in insulin-dependent-diabetes mellitus (IDDM).

• International Journal of Oral Biology
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• v.30 no.3
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• pp.77-84
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• 2005

EGCG[(-)-epigallocatechin gallate], is a major component of green tea has been considered as a major antioxidant constituent. It has been considered as potential chemopreventive and chemotherapeutic agents. However, very little is known about the cellular actions by which EGCG mediates its therapeutic effects. Various aspects of antioxidant activity of EGCG were evaluated in this study. EGCG itself did not show significant cytotoxicity. Significant 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was observed in all ranges of concentration ($0.8-100{\mu}g/ml$) used in this study. Protective effect of EGCG against hydrogen peroxide induced cell death was observed. Relatively high lipid peroxidation inhibitory activity were detected ($IC_{50}$ was about $20{\mu}g/ml$). EGCG also dose-dependently enhanced the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in V79-4 cells. In concentrations of $100{\mu}g/ml$ of EGCG, activities of SOD, CAT and GPX were measured as 36.9 U/mg of protein, 22.9 U/mg of protein and 17.8 U/mg of protein, respectively. When these values were compared with those of the control groups (24.9 U/mg of protein, 14.9 U/mg of protein and 11.7 U/mg of protein), the relative increases were calculated as 48, 54 and 52%, respectively. Taken together, our findings suggest that EGCG can act as an antioxidant by scavenging radicals and enhancing antioxidant enzyme activities.

• Natural Product Sciences
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• v.12 no.2
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• pp.67-73
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• 2006

Antiallergic activities of two variants of Artemisia princeps Pampanini SJ-1 (named as Sajabalssuk) and SS-1 (named as Sajuarissuk) cultivated in Ganghwado, which contain high content of eupatilin compared to those cultured by other places, were investigated to evaluate the possibility as inhibitors against allergic diseases. Ethanol and supercritical fluid extracts of SJ-1 and SS-1 inhibited the release of ${\beta}-hexosaminidase$ from RBL-2H3 cells, although their water extracts were inactive. These extracts potently inhibited lipopolysaccharide-induced NO production of RAW264.7. However, these extracts almost did not scavenge free radicals. Oral administration of these extracts to mice inhibited passive cutaneous anaphylaxis reaction induced by IgE, and acute dermatitis induced by 12-O-tetradecanoylphorbol-13-acetate. However, these extracts did not inhibit chronic dermatitis. Scratching behaviors, vascular permeability, and writhing syndromes were weakly inhibited by these extract at a dose of 50 mg/kg. Based on these findings, we believe that SJ-1 and SS-1 can improve IgE-induced allergic diseases such as rhinitis and asthma.

• The Journal of Korean Medicine
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• v.29 no.5
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• pp.52-66
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• 2008

Objectives :Ginkgo-Chunghyul-dan (GCHD) is newly developed herbal medicine to prevent and treat stroke. In this study, we investigated whether the GCHD had antioxidant activity and anti-platelet aggregation effect in vitro and hypolipidemic activities in vivo. Methods :Anti-oxidant activity of GCHD was measured using the Blois method, anti-platelet effect of GCHD was assessed by the Born method, and hypolipidemic activities of GCHD were evaluated in corn oil- or Triton WR-1339-induced and cholesterol-fed rats. Results :GCHD showed anti-oxidant activity in the study inhibiting the formation of 1-diphenyl-2-picrylhydrazyl radicals and xanthine oxidase activity. GCHD had anti-platelet aggregation activity. GCHD significantly lowered total cholesterol (TC), triglyceride (TG), and low density lipoprotein cholesterol (LDL-C) in high cholesterol diet and Triton WR-1339 induced model TG in corn oil-induced model. GCHD had no acute toxicity at a single dosage. Conclusion : These results suggest that GCHD has the potential to treat hyperlipidemia and stroke.