• Korean Journal of Pharmacognosy
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• v.29 no.4
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• pp.353-356
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• 1998

Seven flavonoids were isolated from the BuOH extract of the Stem bark of Platycarya strobilacea (Juglandaceae). On the basis of spectroscopic evidences, the structures of these compounds were established as quercetin, 3', 4', 5', 5, 6, 7-hexahydroxyflavone, morin, myricetin, myricitrin, quercitrin and afzelin, respectively.

• YAKHAK HOEJI
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• v.37 no.3
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• pp.306-310
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• 1993

The leaves of Cedrela sinensis have been used for food at south area in Korea and oriental medicine for treating enteritis, dysentery and itch. Kaempferol, methyl gailate, quercetin, afzelin, quercitrin, isoquercitrin and rutin were isolated from the leaves of this plant and characterized by spectral data. These compounds are reported for the first time from this plant.

• Korean Journal of Pharmacognosy
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• v.21 no.3
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• pp.197-200
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• 1990

Quercetin, trifolin and quercitrin were isolated from the leaves of Machilus thunbergii Sieb. et Zucc. (Lauraceae) and characterized by spectral data. These are reported for the first time from this plant.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.1
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• pp.76-79
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• 1996

생강나무 (Libdera obtusiloba BL.)의 페놀성 화합물들을 분리하기 위하여 잎고 줄기의 MeOH 엑스로부터 계통 분획한 EtOAc 분획물은 silica gel column chro-matography로 분리하여 2종의 화합물을 얻었다. IR, UV,$^1H-NMR$, $^13C-NMR$ 등의 분석을 행하여 화학구조를 밝힌 결과 이들 화합물의 화학구조는 잎에서 $quer-cetin-3-O-\alpha-L-rhamnopyranoside(quercitrin),$ 줄기에서는 quercetin $3-O-\beta-D-galactoyranoside(hyperoside)로$ 각각 결정하였다. 이 화합물들은 생강나무에서 처음으로 분리하였다.

• Korean Journal of Pharmacognosy
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• v.27 no.3
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• pp.219-223
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• 1996

From the rachis of Cedrela sinensis A. Juss., methyl gallate, quercitrin, bis-(p-hydroxyphenyl)ether, adenosine, isoquercitrin, rutin, (+)-catechin and (-)-epicatechin were isolated and characterized by spectral data.

• Preventive Nutrition and Food Science
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• v.13 no.3
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• pp.241-244
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• 2008

Methanol extracts were prepared from Z. schinifolium leaf and successively fractionated with chloroform, butanol, and water. The butanol fraction exhibited the highest antioxidative activities. Therefore the butanol fraction was purified and a chemical structure was identified by $^1H-^{13}C-NMR$ spectra, and FT-IR. The isolated antioxidative substance was identified as quercitrin.

• 한국약용작물학회:학술대회논문집
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• 2008.05a
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• pp.154-155
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• 2008

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.211.1-211.1
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• 2003

On the purpose of develcpement of antioxidative compound from natural sources, medicinal plants known to have antioxidant actuvity have been examined concening DPPH radical scavenging activity and SOD-liked activities. Among 8 plants exhibiting the activity, Houttuynia cordata THUNB was selected as resources to search for active compounds due to rareness of study. The antioxidative compounds from Houttuynia cordata THUNB,quercitrin was assayed using a DPPH free radical. The DPPH radical scavenging activity of quercitrin was similar to that of BHA and Ascorbic acid

• Applied Biological Chemistry
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• v.39 no.4
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• pp.320-326
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• 1996

Seven antioxidative flavonoids were isolated from Jindalrae flowers (Rhododendron mnonulatum Turcz.), an edible plant in Korea. These compounds were identified as afzelin, ampelopsin, catechin, myricetin, myricitrin, quercetin and quercitrin on the basis of IR, UV, FAB-MS, $^1H\;NMR,\;and\;^{13}C\;NMR$ data. These compounds were consisted of two flavonols, three flavonol glycosides, a flavane, and a dihydroflavonol. The flavonol glycosides (14.4 g) present in th ethyl ether and ethyl acetate fractions comprised up to 82% of their total flavonoid amount (17.6 g) finally recovered by means of polyamide C-200 column chromatography, preparative TLC, recrystallization, and Sephadex LH-20 column chromatography. The antioxidant activities were measured in an ethanol solution of linoleic acid in the presence of ferric thiocyanate. The antioxidant efficiency increased in the order of afzrlin<$\alpha-tocopherol$

• Korean Journal of Medicinal Crop Science
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• v.7 no.4
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• pp.303-307
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• 1999

Three antioxidative compounds were isolated from the EtOAc extract of the fruits of Pyrus ussuriensis. On the basis of spectroscopic evidences, the structures of these compounds were established as 1, 4-dibenzenediol, chlorogenic acid and quercitrin. The DPPH free radical scavenging activities of 1, 4-dibenzenediol $(RC_{50}\;:\;0.4{\mu}g)$ and chlorogenic acid $(RC_50\;:\;4{\mu}g)$ were more effective than those of BHA $(RC_{50}\;:\;14{\mu}g)$ and a-tocopherol $(RC_{50}\;:\;12{\mu}g)$