• Korean Journal of Pharmacognosy
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• v.42 no.2
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• pp.195-200
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• 2011

In this study, we investigated on antioxidative activity, tyrosinase inhibitory activity and nitric oxide(NO) production inhibitory activity in the hot water extract of Taraxacum coreanum and its fractions. The total polyphenol and flavonoid contents of the extract were found to be 65.42 mg/g and 9.83 mg/g, respectively. And the total polyphenol and flavonoid contents of the ethyl acetate fraction were found to be 168.23 mg/g and 31.92 mg/g, respectively. In DPPH radical scavenging ability, $SC_{50}$ values of the ethyl acetate and butanol fraction were exhibited 64.65 ${\mu}g/ml$ and 277.42 ${\mu}g/ml$, respectively. Moreover, ethyl acetate fraction showed higher inhibitory activity than other samples in tyrosinase inhibitory activity. In NO production inhibitory activity, the extract and its fractions showed NO production inhibitory effect. Especially, the ethyl acetate, chloroform and butanol fraction was exhibited higher NO production inhibitory activity than other samples. As a result, the ethyl acetate and butanol fraction from the water extract of T. coreanum could be applicable to functional materials for skin-related fields.

• YAKHAK HOEJI
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• v.59 no.1
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• pp.12-16
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• 2015

Several 8-cycloalkoxychrysin analogs were synthesized from 6-benzyloxy-5,8-dihydroxyflavone and cycloalkanols in 2 steps and we evaluated their inhibitory activities against NO production from LPS-induced RAW 264.7 cells. Among tested analogs, two analogs with cyclopentyl substructure (796 and 798) showed strong inhibitory activity against NO production.

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2481-2486
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• 2014

Twelve thienyl/furanyl-hydroxyphenylpropenones were systematically designed and synthesized, and evaluated for their inhibitory effect on LPS-induced ROS and NO production in RAW 264.7 macrophages. Compound 11 displayed the most significant inhibitory activity of LPS-induced ROS and NO production in RAW 264.7 macrophages. Structure-activity relationship study indicated that para-hydroxyphenyl moiety plays an important role for inhibitory activities on both LPS-induced ROS and NO production as well as 3-thienyl moiety on molecule.

• Korean Journal of Medicinal Crop Science
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• v.21 no.3
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• pp.191-196
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• 2013

The effect on the antioxidant activity and Nitric Oxide activity production inhibitory activity of Taraxacum has not been known. Therefore, phenolics and flavonoid contents were investigated from the ethanol extracts of five different Taraxacum species. The results showed that, among the five Taraxacum, T. hallaisanensis contains the highest total phenolic and flavonoid contents. When the antioxidant activity was measured by DPPH, $ABTS^+$ and reducing power activity, the free radical scavenging activity of T. hallaisanensis was also the highest among five Taraxacum species. However, measurement by CCK-8 assay in Raw264.7 cells indicated that the extracts of Taraxacum species have no effect on cell viability. Moreover, we also investigated the effect of Taraxacum species on NO scavenging activity in lipopolysaccharide (LPS)-stimulated Raw264.7 cells. The results clearly showed that Taraxacum species inhibited NO production, and the inhibitory effect of T. hallaisanensis was the strongest. The above results suggested that Taraxacum species affected the antioxidant and NO scavenging activity, and among the five species, antioxidant and NO scavenging activity assay of T. hallaisanensis was significantly higher than those of other four Taraxacum species. Therefore, T. hallaisanensis could be used as a potential drug with anti-oxidant and anti-inflammatory effect.

• Biomolecules & Therapeutics
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• v.9 no.3
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• pp.183-187
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• 2001

Nitric oxide (NO) produced in large amounts by the inducible nitric oxide synthase (iNOS) is known to be responsible for the vasodilation and hypotension observed in septic shock and inflammation. The inhibitors of iNOS, thus, may be useful candidate for the treatment of inflammatory diseases accompanied by the overproduction of NO. We prepared alcoholic extracts of Chinese medicinal plants and screened their inhibitory activity against NO production in lipopolysaccharide (LPS)-activated macrophages. Among the 80 kinds of extracts of herbal drugs, 15 extracts showed potent inhibitory activity of NO production above 80% at the concentration o$50\mu\textrm{g}/ml$. These potent extracts showed dose dependent inhibition of NO production of LPS-activated macrophages at the concentration of 50, 30,$10\mu\textrm{g}/ml$. Especially, Rhus chinensis, Senecio scandens and Wikstroemia indica showed most potent inhibition above 50% at the concentration of $10\mu\textrm{g}/ml$. These plants are promising candidates for the study of the activity-guided purification of active compounds and would be useful for the treatment of inflammatory diseases and endotoxemia accompanying the overproduction of NO.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1339-1344
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• 2013

We have synthesized several glycosyl ergosterols and 5,6-dihydroergosterols (DHE) and examined their effects on production of nitric oxide (NO) and iNOS protein expression in LPS-treated RAW264.7 macrophage cells. Our results showed that DHE derivatives inhibited production of NO and iNOS protein expression more strongly than ergosterol derivative. Especially, DHE-Glc exhibited most potent inhibitory activity without cytotoxicity up to the concentration of $100{\mu}M$.

• Natural Product Sciences
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• v.18 no.3
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• pp.141-146
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• 2012

Veronica peregrina (Scrophylariaceae) has been widely used as a Korean traditional medicine for the treatment of various pathological conditions including infection, hemorrhage and gastric ulcer. In the current study, we investigated the inhibitory effect of methanolic extracts of V. Peregrina (VPM) on the LPS-mediated nitric oxide (NO) production in mouse (C57BL/6) peritoneal macrophages. NO production was significantly down-regulated by the treatment of VPM dose dependently. To evaluate the mechanism of the inhibitory action of VPM on NO production, we performed iNOS enzyme activity assay and checked the change of inducible nitric oxide synthase (iNOS) levels by Western blotting. Although VPM did not affect iNOS enzyme activity, iNOS protein expression was attenuated by VPM indicating VPM inhibits NO production via suppression of iNOS enzyme expression. In addition, VPM attenuated the expression of another pro-inflammatory mediator such as cyclooxygenase-2 (COX-2) in a dose dependent manner. We also found that VPM can reduce trypsin-induced paw edema in mice. Based on this study, we suggest that V. peregrina may be beneficial in diseases which related to macrophage-mediated inflammatory disorders.

• Korean Journal of Medicinal Crop Science
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• v.24 no.2
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• pp.129-135
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• 2016

Background: In this study, we investigated the antibacterial and nitric oxide (NO) production inhibitory activities of 75% ethanol extract of Prunus sargentii branches and its fractions against acne pathogens. Methods and Results: The antibacterial activity against acne causing pathogens was determined using the disc diffusion assay. The ethyl acetate fraction showed higher activities against Propionibacterium acnes, Staphylococcus aureus and Staphylococcus epidermidis than those shown by other fractions. In the DPPH radical and NO scavenging assays, the butanol fraction showed strong DPPH radical and NO scavenging abilities. These activities were related to the total polyphenol and flavonoid contents of butanol fraction. On the other hand, the chloroform and ethyl acetate fractions exhibited the highest NO production inhibitory activity in Lipopolysaccharide (LPS)-stimulated Raw 264.7 cells compared to those exhibited by other fractions. Conclusions: The extract and its ethyl acetate fraction from the branches of P. sargentii exhibited antibacterial activity and could be used as functional materials in antimicrobial related fields. Moreover, the chloroform and ethyl acetate fractions are potential antiinflammatory agents and butanol fraction acts as an effective radical scavenger.

• Natural Product Sciences
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• v.11 no.1
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• pp.16-21
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• 2005

Nitric Oxide (NO), derived from L-arginine, is produced by two types (constitutive and inducible) of nitric oxide synthase (NOS: cNOS and iNOS). The NO produced in large amounts by the iNOS is known to be responsible for the vasodilation and hypotension observed in septic shock, cancer metastasis and inflammation. The inhibitors of iNOS, thus, may be useful candidates for the treatment of inflammatory diseases accompanied by the overproduction of NO. We prepared alcoholic extracts of herbal drugs which have been used for the treatment of inflammation in oriental medicine. We have screened the inhibitory activity of NO production in lipopolysaccharide (LPS)-activated macrophages after the treatment of these extracts. Among 82 kinds of extracts of herbal drugs, 35 extracts showed the potent inhibitory activity of NO production above 50% at the concentration of $50\;{\mu}g/mL$. The inhibitory activities of NO production were also evaluated for several solvent fractions at two different concentrations. Especially, hexane and EtOAc fractions of Alpinia officinarum, Angelica gigas, Ostericum koreanum, Saussurea lappa, Torilis japonica, and hexane fractions of Agrimonia pilosa, Machilus thunbergii, Hydrangea serrata, Magnolia obovata, Prunella vulgaris, Tussilago farfara, and EtOAC fractions of Perilla frutescence showed a significant activity at 10 and/or $25\;{\mu}g/mL$. In Western blot analysis, the hexane fractions ($5\;{\mu}g/mL$) of Magnolia obovata and Saussurea lappa, and EtOAc fractions ($20\;{\mu}g/mL$) of Hydrangea Serrata, Perilla frutescence and Torilis japonica inhibited the expression of iNOS protein in LPS-activated macrophages. These plants may be promising candidates for the study of the activity-guided purification of active compounds and might be useful for the treatment of inflammatory diseases and endotoxemia accompanying overproduction of NO.

• Biomolecules & Therapeutics
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• v.17 no.1
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• pp.79-85
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• 2009

Polyphenolic compounds are reported to have various pharmacological activities such as anti-oxidative, anti-cancerous, anti-inflammatory and anti-aging effects. Although numerous papers explore their functional roles in many different cellular actions, not many studies handle their structural features in anti-inflammatory responses. In this study, therefore, we examined structural role of substituted transstilbenes in their NO inhibitory and NF-${\kappa}B$ suppressive activities. Of 10 compounds tested, 4 compounds (cinnamic acid, resveratrol, piceatannol and curcumin) displayed NO inhibitory activities in a dose-dependent manner. Similarly, these compounds blocked LPS-induced cytotoxicity of RAW264.7 cells. All NO inhibitory compounds also inhibited $I{\kappa}B{\alpha}$ phosphorylation, a hallmark for NF-${\kappa}B$ activation. However, these inhibitory compounds exhibited distinct suppressive pattern in tumor necrosis factor (TNF)-${\alpha}$- or phorbol-12-myristate-13-acetate (PMA)-induced NF-${\kappa}B$ and AP-1 activation. According to structure-activity relationship study, polarity and size of ring B seem to be important for diminishing NO production. Therefore, our data suggest that substituted trans-stilbenes can be developed as novel anti-inflammatory drug or further developed as lead compounds for another improvement.