• The Korean Journal of Physiology and Pharmacology
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• v.17 no.1
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• pp.37-42
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• 2013

Taxifolin glycoside is a new drug candidate for the treatment of atopic dermatitis (AD). Many drugs cause side effects such as long QT syndrome by blocking the human ether-a-go-go related gene (hERG) $K^+$ channels. To determine whether taxifolin glycoside would block hERG $K^+$ channels, we recorded hERG $K^+$ currents using a whole-cell patch clamp technique. We found that taxifolin glycoside directly blocked hERG $K^+$ current in a concentration-dependent manner ($EC_{50}=9.6{\pm}0.7{\mu}M$). The activation curve of hERG $K^+$ channels was negatively shifted by taxifolin glycoside. In addition, taxifolin glycoside accelerated the activation time constant and reduced the onset of the inactivation time constant. These results suggest that taxifolin glycoside blocks hERG $K^+$ channels that function by facilitating activation and inactivation process.

• Journal of the Korean Wood Science and Technology
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• v.29 no.2
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• pp.133-139
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• 2001

The structures of six flavonoids isolated from heartwood of Prunus sargentii(Rosaceae) were analyzed by Mass and NMR spectrometry. These flavonoids were grouped into dihydroflavonol, flavanone, and flavanone glycoside, and identified as follows : 3,3',4',5,7-pentahydroxyflavanone(taxifolin) as a dihydroflavonol, 5-hydroxy-7-methoxyflavanone(pinostrobin), 4',5,7-trihydroxyflavanone(naringenin), 3',4',5,7-tetrahydroxyflavanone(eriodictyol), 5,7-dihydroxyflavanone(pinoccmbrin) as a flavanone and 7-hydroxyflavanone 5-O-${\beta}$-D-glucopyranoside(verecundin) as a flavanone glycoside.

• Food Science and Biotechnology
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• v.15 no.3
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• pp.424-430
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• 2006

Low molecular weight polyphenols were isolated from hot water extracts of radiata pine (Pinus radiata) bark using a Sephadex LH-20 column and characterized by $^1H$ and $^{13}C$ NMR, UV, FT-IR, and GC-MS analyses. Major compounds isolated and identified were protocatechuic acid, trans-taxifolin, and quercetin. Trans-taxifolin, an important intermediate in biosynthetic route of proanthocyanidin (PA), was isolated in large quantities and indicates that PA is a major component of radiata pine bark. Small amounts of polyphenols were identified by GC-MS analysis. The presence of p-hydroxybenzoic acid, vanillic acid, protocatechuic acid, cis- and trans-feruic acid, p-coumaric acid, trans-caffeic acid, (-)-epicatechin, (+)-catechin, trans- and cis-taxifolin, (+)-gallocatechin, and quercetin was confirmed by comparison of mass fragmentation patterns and retention times (RT) with authentic samples. In addition, the presence of astringenin, astringenin glycoside, trans- and cis-leucodelphinidin was strongly assumed from characteristic mass fragment ions due to their conjugated structure and retro Diels-Alder reaction, and also from biosynthetic route of PA. GC-MS analysis allowed us to detect small amounts of phenolic acids and flavonoids and eventually discriminate trans- and cis-configuration in the identified polyphenols.

• Journal of the Korean Wood Science and Technology
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• v.34 no.6
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• pp.51-60
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• 2006

Juglans mandshurica barks were collected, extracted with acetone-$H_2O$ (7:3, v/v), fractionated with n -hexane, $CH_2Cl_2$, and EtOAc, and freeze dried to give some dark brown powder. The EtOA cand $H_2O$ soluble fractions were chromatographe d on a Sephadex LH-20 column using $H_2O$-MeOH and EtOH-hexane mixture as eluents. Spectrometric analysis such as NMR and MS, including TLC,were performed to characterize the structures of the isolated compounds. From the EtOAc and $H_2O$ soluble fractions, three flavanols (1~3), three flavonols (4~6) and five flavonol glycosides (7~11) were isolated and elucidated.

• Journal of Korea Foresty Energy
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• v.20 no.2
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• pp.9-19
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• 2001

This study was carried out to investigate natural insectifuge materials from tree extractives in order to substitute for organic synthetic insecticides for food wrapping corrugated board. Tree samples were collected, extracted, fractionated with hexane, $CH_2Cl_2$, ethylacetate(EtOAc) and $H_2O$, and then freezed dried for further study. EtOAc or $H_2O$ fractions were chromatographed on a Sephadex LH-20 column for isolation and purification, and the isolated compounds were characterized by spectroscopic tools such as NMR and MS. Crude extractives of EtOAc and $H_2O$ fractions were added to the printing ink for corrugated board with the concentration of 2% or 3% based on the weight of the ink, then the prepared ink was printed on the corrugated board to be used for evasion test using larva of indian meal moth(Plodia interpunctella(Hubner)). Robtin, dihydrorobinetin and leucorobinetinidin were isolated from the wood extractives of black locust(Robinia pseudoacacia) and the bark of poplar(Populus alba $\times$ glandulosa) contained many kinds of compounds such as (+)-catechin, naringenin, aromadendrin, eriodictyol, sakuranetin and its glycoside, taxifolin, neosaturanin, salireposide, p-coumaric acid and aesculin. Much of (+)-catechin was isolated from the bark extractives of willow(Salix koreensis) in addition to (+)-gallocatechin and p-coumaric acid and the bark of weeping willow(Salix babylonica) also contained (+)-catechin, (+)-gallocatechin, dihydromyricetin and myricetin.