• The Korean Journal of Food And Nutrition
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• v.17 no.2
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• pp.138-146
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• 2004

This study was designed to investigate antioxidative activity of substances isolated from 25 kinds of useful plants resources toward free radical and human low density lipoprotein(LDL). Methanol extracts of Oenothers odorate had the highest antioxidative activity similar with ${\alpha}$-tocopherol. Methanol extracts of Oenothers odorate was extracted again by the ethylacetate. The ethylacetate soluble acidic fraction obtained from methanol extract of Oenothers odorate showed highest activity toward human LDL. Each fraction was purified through Sepadex LH-20 chromatography by elution of chloroform-methanol mixture (90:10 v/v). Fraction, F-2 obtained from Oenothers odorate showed at highest levels of electron donating activity. Fraction, F-2 was identified as 3,4-dihydroxybenzoic acid and 3-hydroxycinnamic acid.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.493-497
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• 2002

The polyphenol compounds of Korea ginseng radix were extracted with 60% acetone for 4 days at room temperature and purified using Sephadex LH-20 column chromatography, MCI gel column chromatography, Bondapak $C_{18}$, column chromatography, TLC and HPLC. As a result in three compounds were isolated from Korean ginseng. In the inhibitory activities of angiotensin converting enzyme, compound Ⅱ showed the highest value of 31.86% inhibition at 157 ppm. Compound I showed 19.4% inhibition at 157 ppm. In the inhibitory activities of xanthine oxidase, compound I, II showed complete inhibition at 666 ppm but compound III didn't have inhibitory activity. In the inhibitory activities of tyrosninase, compound III showed 6.1% inhibition at 300 ppm and 28.6% at 400 ppm.

• YAKHAK HOEJI
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• v.36 no.3
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• pp.205-211
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• 1992

A simple dignostic method using Fast Atom Bombardment mass spectrometry was applied to the characterization of green tea flavonols from the eluates of Sepahadex LH-20 column chromatography. From the ethyl acetate extracts, crude mixture of flavonol fraction(Fr.$1{\sim}4$) were separated by the stepwise gradient elution with 30, 45, and 60% aqueous acetone. Procyanidine B analogues were found to be typical constituents of Fr. 1. Main components of Fr. 2 were catechins and gallo-catechins. Fr. 3 contained mainly ester type compounds, catechin-gallates, gallocatechin-gallates with their analogues. Fr. 4 was contaminated with some phthalate esters.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.959-967
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• 2003

The polyphenol compounds of Korean pears were extracted with 60% acetone for 4 days at room temperature and purified using Sephadex LH-20 column chromatography, MCI gel column chromatography, Bondapak $C_{18}$ column chromatography, TLC, and HPLC. As a result, three compounds were isolated. The chemical structures of each compound were determined and identified using NMR, FAM-mass, and FT-IR. The compounds were confirmed as (+)-catechin (compound A), (+)-gallocatechin (compound B), (-)-epigallocatechin (compound C), and procyanidin B-3-3-o-gallate (compound D).

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.129-133
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• 2004

The active compound responsible fer the anti-oxidant activity in Chinese cabbage kimchi were isolated and identified. The dichloromethane fraction of Chinese cabbage kimchi with the greatest anti-oxidant activity was used. Silica gel column chromatography, Sephadex LH-20 column chromatography, TLC, and Sep-pak catridge were used for isolating the active compounds and IR, EI-MS, GC-MS, $^{1}H-NMR$, $^{13}C-NMR$ were used to identify the structure of the isolated compounds. 3-(4'-Hydroxyl-3',5'-dimethoxyphenyl)propionic acid of molecular weight 226, which had 3.4 times greater free radical scavenging activity than Vit. C and significantly greater anti-oxidant activity against LDL oxidation than the control, was obtained, This active principle may be beneficial in preventing hyperlipidemia and artherosclerosis in human.

• Applied Biological Chemistry
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• v.46 no.3
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• pp.251-256
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• 2003

The polyphenol fractions of Korean ginseng were purified using Sephadex LH-20, MCI gel, Bondapak $C_{18}$ TLC, and HPLC from the 60% acetone soluble fraction. Fraction I showed 48.16%, 79.71% and 43.55% inhibition at 150 ppm against lipid oxidation in the presence of copper ion, superoxide and hydrogen peroxidation. Electron donating abilities of fraction II showed 35.17% inhibition at 200 ppm. Fraction III showed 48.49% and 25% inhibition at 150 ppm against lipid oxidation in the presence of ferrous ion and hydroxy radical ion. The phospholipase $A_2$ inhibitory effect of fraction III was 48.9% at the concentration of $60\;{\mu}g/ml$. The cytotoxic effects of fraction II was the highest (73.29% at 0.25 mg/ml) among the tested polyphenol fractions.