• Journal of Microbiology
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• v.45 no.6
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• pp.578-582
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• 2007

The primary objective of this study was to assess the in vitro melanogenesis inhibitory effects of methanolic extracts of the edible and medicinal lichens, Umbilicaria (Gyrophora) esculenta and Usnea longissima. The quantities of the total phenolic compounds of methanolic extract of the two lichen extracts were determined to be 1.46% and 2.62%, respectively. In order to evaluate the antioxidative effects of the extracts, we also measured electron donating abilities (EDA) and lipid peroxidation rates. The EDA values measured by the reduction of 1.1'-diphenyl-2-picrylhydrazyl (DPPH) were 72.8% and 80.7% for the extracts, with $SC_{50}$ (median scavenging concentration) values of $1.29{\pm}0.05\;mg/ml$ and $1.03{\pm}0.06\;mg/ml$, respectively. The rates of inhibition of lipid peroxidation using linoleic acid were 92.1% and 97.3% for the extracts, with $IC_{50}$ (median inhibitory concentration) values of $0.57{\pm}0.05\;mg/ml$ and $0.53{\pm}0.06\;mg/ml$, respectively. The inhibitory rates of the extracts against tyrosinase were 67.4% and 84.8%, respectively. The extracts were shown to reduce melanin formation in human melanoma cells. Melanin contents in the samples treated with 0.01% and 0.1% U. esculenta were 47.1% and 31.2%, respectively, and those treated with 0.01% and 0.1% Usnea longissima were 51.1% and 34.9%, respectively, whereas a value of 54.0% was registered when ascorbic acid was utilized as a positive control. In addition to direct tyrosinase inhibition, it was determined that the lichen extracts affected the activity of tyrosinase via the inhibition of tyrosinase glycosylation. As a result, the methanolic extracts of U. esculenta and Usnea longissima evidenced melanogenesis inhibitory effects, which occurred via multiple routes.

• YAKHAK HOEJI
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• v.49 no.1
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• pp.30-37
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• 2005

Xuesaitong Ruanjiaonang (XR), a soft capsule containing Panax notoginseng saponins as main ingredients, is believed to remove extravasated blood and increase cerebral blood flow by improving blood circulation, and therefore, has been used in China to treat ischemic stroke or hemiplegia caused by cerebral thrombosis. To characterize pharmacological actions of XR, the present study evaluated its effects on neuronal cell damage induced by various oxidative insults or excitotoxic amino acids in primary cultured rat cortical cells. The neuronal cell viability was not affected by XR with the exposure for 2 h at the concentrations tested in this study ($10{\sim}1000\;{\mu}g/ml$). However, significant reduction of the cell viability was observed when the cultured cells were exposed to XR at $1000\;{\mu}g/ml$ for 24 h. XR was found to concentration-dependently inhibit the oxidative neuronal damage induced by $H_{2}O_2$, xanthine/xanthine oxidase or $Fe^{2+}$/ascorbic acid. In addition, it dramatically inhibited the excitotoxic damage induced by glutamate or N-methyl-D-aspartate (NMDA). We found that the NMDA-induced neurotoxicity was inhibited more effectively and potently than the glutamate-induced toxicity. Moreover, XR was found to exert mild inhibition of lipid peroxidation induced by $Fe^{2+}$/ascorbic acid in rat brain homogenates and some 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity. Taken together, these results demonstrate neuroprotective and antioxidant effects of XR, showing inhibition of oxidative and excitotoxic damage in the cultured cortical neurons, as well as inhibition of lipid peroxidation and its radical scavenging activity. Considering that excitotoxicity and oxidative stress pl ay crucial roles in neuronal cell damage during ischemia and reperfusion, these results may provide pharmacological basis for its clinical usage to treat ischemic stroke.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2003.06a
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• pp.119-119
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• 2003

• Proceedings of the Korean Aquaculture Society Conference
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• 2004.05a
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• pp.144-145
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• 2004

• Journal of Pharmacopuncture
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• v.11 no.1
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• pp.109-118
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• 2008

Objective : The objective of this study was to compare the antioxidant effects of hot pepper extract and capsaicin. Methods : In vitro, antioxidant activities were examined by DPPH radical scavenging activity, total antioxidant capacity(TAC), oxygen radical scavenging capacity(ORAC), inhibition of induced lipid peroxidation using liver mitochonria and total phenolic contents. Results : 1. DPPH free radical scavenging activities at the concentrations of both 1 and $10mg/m{\ell}$ were 1.2 to 1.9 times higher in capsaicin than in hot pepper extract. The concentration of capsaicin required for 50% radical scavenging was lower than that of hot pepper extract(3.9 vs $5.9mg/m{\ell}$), indicating that capsaicin had higher DPPH radical scavenging activity than hot pepper extract. 2. Total antioxidant capacities of capsaicin at the concentrations of 0.1 and 1mg/ml(13.8 and 41.3 nmol Trolox equivalent) were not significantly different from those at the concentrations of 1 and $10mg/m{\ell}$(11.4 and 41.2nmol Trolox equivalent), indicating that capsaicin showed 10 times higher ABTS radical scavenging activity compared to hot pepper extract. 3. ORAC of capsaicin at the concentrations of 1, 5, 10 and 100 mg/ml were 0.04, 0.17, 0.29 and 1.74nmol gallic acid equivalent, respectively. On the other hand, ORAC of hot pepper extract at the concentrations of 1, 5, 10 and $100{\mu}g/m{\ell}$ were 0.15, 0.44, 0.75 and 2.49nmol gallic acid equivalent, respectively, indicating that capsaicin showed higher peroxyl radical scavenging activity than hot pepper extract. 4. Inhibition of lipid peroxidation caused by hot pepper extract at the concentrations of 1 and $10mg/m{\ell}$ were 12.2 and 61.4%, respectively. Inhibition of lipid peroxidation caused by capsaicin at the concentrations of 1 and $10mg/m{\ell}l$ were 64.0 and 96.8%, respectively. Thus capsaicin showed 10 times stronger effect in inhibiton of lipid peroxidation than hot pepper extract. 5. Total phenolic contents of hot pepper extract at the concentrations of 0.1 and $1mg/m{\ell}$ were 1.4 and 20.8nmol gallic acid equivalent, respectively. Total phenolic contents of capsaicin at the concentrations of 0.1 and $1mg/m{\ell}$ were 6.1 and 55.4 nmol gallic acid equivalent, respectively, indicating that capsaicin had 2.7 to 4.3 times higher total phenolic contents than hot pepper extract. Conclusions : In summary, the results of this study demonstrate significant antioxidant activity of hot pepper extract, although the activity was lowered compared to capsaicin, suggesting that hot pepper extract play a role in prevention of oxidative-related diseases.

• Archives of Pharmacal Research
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• v.16 no.1
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• pp.13-17
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• 1993

Several naturally occurring furanocoumarins significantly inhibited microsomal lipid peroxidation not only mediated by endogeneous iron and NADPH but also initiated by $CCL_4$ metabolites, phellopterin, a potent inhibibitor of cytochrome p-450, exhibited an almost complete inhibition of $CCL_4$-induced hepatotoxicity as measured by sGPT activity 24 hr after $CCL_4$ intoxication, whereas other furanocoumarins such as imperation, byakangelicin and oxypeucedanin methanolate exerted no protective effect. When compared with other cytochrome P-450 inhibitors(SKF-52A, AIA) and silymarin given at the same dose level $(ED_{50})$, phellopterin still showed a significant inhibition of hepatotoxicity which was even stronger than that of AIA, known as a typical suicide inhibitor. Phellopterin was partially effective when given 30 min after $CCL_4$ treatment. Repeated administrations of phellopterin, however, resulted in a complete loss of the protection against $CCL_4$-induced hepatotoxicity.

• Preventive Nutrition and Food Science
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• v.15 no.1
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• pp.30-35
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• 2010

The potential biological activities of methanol extract and 5 fractions (hexane, $CH_2Cl_2$, EtOAc, BuOH and water) from roots of Astragalus membranaceus were examined by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, hydroxyl radical (${\cdot}OH$) scavenging activity, reducing power assays, lipid peroxidation inhibitory activity, $\alpha$-amylase and $\alpha$-glucosidase inhibition assays. The EtOAc fraction showed high DPPH free radical scavenging activity ($EC_{50}=170.34\;{\mu}g/mL$), hydroxyl radical scavenging activity ($EC_{50}=32.14\;{\mu}g/mL$), lipid peroxidation inhibitory activity ($EC_{50}=52.46\;{\mu}g/mL$) and a concentration dependence, with OD value ranging from 0.234 to 0.345 (0.1 to 0.5 mg/mL), for reducing power. The EtOAc fraction has the highest total phenolic content ($142.13\;Gal\;{\mu}g/mg$) and the $CH_2Cl_2$ fraction has the highest flavonoid content ($71.63\;Que\;{\mu}g/mg$). Meanwhile, hexane and EtOAc showed certain $\alpha$-amylase and $\alpha$-glucosidase inhibition activities. These results suggest that the methanol extract and fractions from Astragalus membranaceus root have significant antioxidant and anti-diabetes activities, which could be used as a potential source of pharmaceutical materials.

• Preventive Nutrition and Food Science
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• v.16 no.1
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• pp.89-94
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• 2011

The potential biological activities of water and ethanol extracts from two varieties of Rubus coreanus Miquel fruits produced in the Gochang-gun (GR) and Hoengseong-gun (HR) regions of Korea were examined. The hydroxyl radical ($\cdot$OH) scavenging activity, reducing power, lipid peroxidation inhibitory activity, and antiproliferative activity on cancer cells by these extracts were examined, and $\alpha$-amylase and $\alpha$-glucosidase inhibition assays were also performed. The EtOH extract from GR showed high hydroxyl radical scavenging activity ($EC_{50}=119.47{\pm}5.13\;{\mu}g/mL$), lipid peroxidation inhibitory activity ($EC_{50}=213.45{\pm}3.14\;{\mu}g/mL$) and a concentration dependence, with OD values ranging from 0.15 to 0.56 (50 to 200 ${\mu}g/mL$), for reducing power. The EtOH extract from GR has the highest antiproliferative activities on MDA-MB-231 and HepG2 cancer cells among four extracts. Meanwhile, all extracts showed certain $\alpha$-amylase and $\alpha$-glucosidase inhibition activities. These results indicate that extracts from two varieties of R. coreanus fruits have significant antioxidant, anti-diabetic and anti-tumorigenic activities, which suggest these extracts could be a potential source for pharmaceutical.

• Preventive Nutrition and Food Science
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• v.13 no.3
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• pp.176-181
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• 2008

This study analyzed the some of the physiological activities of 70% ethanol extracts of specialty rough rice ('Goami2', 'Keunnunbyeo', and 'Heugkwangbyeo' rough rice cultivars) before and after germination. The physiological activities of the extracts were analyzed for their inhibition of linoleic acid peroxidation, hydrogen peroxide radical scavenging activity, superoxide dismutase-like activity, xanthine oxidase inhibitory activity, and nitrite scavenging effects. The most active rough rice cultivar was 'Heugkwangbyeo' and germinated 'Heugkwangbyeo' rough rice was more effective than ungerminated rough rice, having higher inhibition activity of linoleic acid peroxidation (1.2-fold), hydrogen peroxide radical scavenging activity (1.4-fold), superoxide dismutase-like activity (1.2-fold), and xanthine oxidase inhibitory activity (1.1-fold). The nitrite scavenging effect was increased after germination (2.1-fold) and decreased as pH increased. According to the results obtained in this study, 70% ethanol extracts from germinated 'Heugkwangbyeo' rough rice can be used for industrial applications such as the functional food materials.

• Journal of Acupuncture Research
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• v.18 no.3
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• pp.123-133
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• 2001

Objective : This study was undertaken to determine whether Cordyceps sinensis Sacc. (CSS) extract exerts the protective effect against oxidant-induced alterations in membrane transport function in renal tubules. Methods : Membrane transport fucntion was estimated by examining alterations in p-aminohippurate (PAH) uptake in rabbit renal cortical slices. For induction oxidative stress, slices were treated with an organic peroxide cumene hydroperoxide for 60 min at $37^{\circ}C$. Cumene hydroperoxide inhibited PAH uptake in a time dependent manner. Results : CSS at 0.5-5% concentrations prevented cumene hydroperoxide-induced inhibition of PAH uptake. CSS at 1% also attenuated LDH release and lipid peroxidation induced by cumene hydroperoxide. When slices were treated with 0.2 mM mercury chloride, PAH uptake was inhibited and lipid peroxidation was increased. These changes by mercury were significantly prevented by CSS. Conclusion : These results suggest that CSS prevents oxidant-induced alterations in membrane transport function in rabbit renal cortical slices. Such protective effect of CSS may be attributed to inhibition of peroxidation of membrane lipid.