• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1199-1203
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• 2003

Polyphenols were isolated from Korean green tea using Sephadex LH-20 and HPLC. The isolated polyphenols were procyanidin B-4, procyanidin B-2-3,3'-digallate, prodelphinidin C-2-3,3'-di-O-digallate, (+)-catechin-3-O-rhamnose, procyandin B-5, procyanidin B-7-3-0-gallate, gallate, epiafzelechin-$(4{\beta}{\rightarrow}8)$-epiafzelechin, procyanidin B-3-3-O-rhamnose, afzelechin-$(4{\alpha}{\rightarrow}8)$-catechin, prodelphinidin B-5-3,3'-di-O-digallate and (+)-taxifolin-3-O-D-xyloside. The inhibitory effects of prodelphinidin C-2-3,3'-di-O-gallate and procyanidin B-2-3,3'-digallate $(at\;100{\mu}M)$ on angiotensin.converting enzyme were 68.8 and 54.6%, respectively, while the inhibitory effects of prodelphinidin C-2-3,3'-di-O-gallated and procyanidin B-2-3,3'-digallate $(at\;100{\mu}m)$ on xanthine oxidase were 54.5 and 38.2%, respectively. Lastly, the inhibitory activities of prodelphinidin C-2-3,3'-di-O-gallate $(at\;100{\mu}m)$ on tyrosinase was 42.1%.

• Applied Biological Chemistry
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• v.37 no.6
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• pp.498-502
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• 1994

For glucosyltransferase(GTase) inhibitors, two flavan-3-ols were isolated from Theobroma cacao beam husk. They showed positive reaction with $anisaldehyde-H_2SO_4$ solution, $FeCl_3$ to be confirmed as dimeric flavan-3-ols on TLC and were identified as procyanidin B-1 [(-)-epicatechin-$(4{\beta}{\rightarrow}8)$-catechin] and procyanidin B-3 [(+)-catechin-$(4{\beta}{\rightarrow}8)$-catechin by spectroscopic analysis. Their inhibitory effect on glucosyltranaferase activity was also investigated and procyanidin B-1 showed 50% inhibition at 0.3 mM. They inhibited on the glucosyltransferasa noncompetitively and dimeric flavan-3-ol containing (-)-epicatechin had higer inhibitory activity.

• Applied Biological Chemistry
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• v.41 no.1
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• pp.110-117
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• 1998

Seven kinds of polyphenol compounds having ACE activities were isolated and purified by Sephadex LH-20, MCI-gel CHP-20, ${\um}-Bondapak\;C_{18}$ and Fuji-gel ODS $G_3$ sucessively from cacao bean(Ghana). The chemical structures of each compound were determined and identified using analyzers such as $^1H-NMR$, $^{13}C-NMR$, IR, MS, polarimeter and Elemental Analysis. Inhibition effects of isolated polyphenols on angiotensin converting enzyme (concerned with hypertension) were also observed. The results obtained were as follows,; The compounds isolated and identified were confirmed and determined as compound 1 [(+)-catechin], compound 2 [(-)-epicatechin], compound 3 [procyanidin B-1 : (-)-epicatechin-$(4{\beta}{\rightarrow}8)$-(+)catechin], compound 4 [procyanidin B-2 : (-)-epicatechin-$(4{\beta}{\rightarrow}8)$-(-)-epicatechin], compound 5 [procyanidin B-7 : (-)-epicatechin-$(4{\beta}{\rightarrow}6)$-(+)-catechin], campound 6 (procyanidin B-2,3,3'-O -digallate), compound 7 [cinnamtannin A-2 : (-)-epicatechin-$(4{\beta}{\rightarrow}8)$-(-)-epicatechin-$(4{\beta}{\rightarrow}8)$-(-)-epicatechin-$(4{\beta}{\rightarrow}8)$-(-)-epicatechin]. In the inhibition effect on ACE, procyanidin B-2,3,3'-O-digallate (compound 6) showed a higher value of 94.6% for ACE in $100\;{\um}M$ than other compounds such as (+)-catechin (compound 1), (-)-epicatechin (compound 2), procyanidin B-1 (compound 3), procyanidin B-2 (compound 4), procyanidin B-7 (compound 5) and cinnamtannin A-2 (compound 7) showing 67.9%, 61.9%, 88.6%, 82.5%, 72.2% and 82.3% for ACE, respectively. Inhibition of $4{\beta}{\rightarrow}8$ in coupling bond on the ACE enzyme was more effective than that of $4{\beta}{\rightarrow}6$. Procyanidin containing gallate inhibited more effectively than those containing not any. It was also observed that a lot of hydroxy group in the compounds increased the inhibitory effect.

• Natural Product Sciences
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• v.9 no.2
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• pp.49-51
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• 2003

The underground part of Rosa rugosa Thunb. has been used in Korean folk medicine for treating diabetes. The $^{1}H-NMR$ signal of procyanidin B3 isolated from Rosa rugosa was fully assigned by utilizing $^{1}H-^{1}H$ COSY. Procyandin B3 showed a moderate inhibitory activity against HIV-1 protease.

• KSBB Journal
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• v.8 no.1
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• pp.69-74
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• 1993

For an anti-plaque agent, two flavan-3-ols isolated from Theobroma cacao bean husk showed positive reactions with $H_2SO_4$-anisaldehyde solution, $FeCl_3$, and were identified as monomeric, dimeric flavan-3-ots in TLC. They were (-)-epicatechin and procyanidin B-2(epicatechin-(4$\beta$$\rightarrow$8)-epicatechin). The structures were established by spectroscopic and chemical methods. (-)-Epicatechin had moderate inhibitory activity on GTase at concentration of 1.0mM while procyanidin B-2 showed complete inhibition activity at the same concentration. The hydroxyl group of flavan-3-ol was supposed to be the essential element for inhibition on GTase.

• KSBB Journal
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• v.11 no.5
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• pp.536-542
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• 1996

The isolation of active compounds showing the inhibitory effect on glucosyltransferase(GTase) from cacao bean husk(CBH) extract was carried out for screening of anti-plaque agents. These active compounds were purified by additional column chromatography of MCI-gel CHP-20 and Sephadex LH-20 and their chemical structures were determined by NMR and mass spectroscopy. Two compounds showing the inhibitory effect on GTase from CBH extract were obtained. These compounds showed positive reactions with anisaldehyde-H2SO4 solution and FeCl3, and were identified as dimeric flavan-3-ols on TLC. By NMR and MS data analyses, the structures of two different flavan-3-ols were identified as procyanidin B-1 and procyanidin B-3, respectively.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1084-1088
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• 1996

As a series of study for an anti-gout agent, two flavan-3-ols have been isolated from Oolong tea. They showed positive reaction in $anisaldehyde-H_2SO_4$ solution and $FeCl_3$, which were able to be confirmed in TLC with dimeric flavan-3-ols. The components were identified as procyanidin B-2 and procyanidin B-2-O-3, 3'-di-gallate by spectroscopic analysis. Their inhibitory effect on xanthine oxidase was also investigated and procyanidin B-2-O-3, 3'-digallate showed 60.6% inhibition at $50\;{\mu}mole$. The compound competitively inhibited the xantine oxidase and dimeric flavan-3-ols contanining gallate had higher inhibition activity.

• Journal of Life Science
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• v.30 no.11
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• pp.956-964
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• 2020

The radical scavenging activity measurement system linked with liquid chromatography (LC) is a useful tool for identifying the radical scavenging active compound in a sample composed of numerous compounds such as plant extracts. Using this system, DPPH and ABTS radical scavenging activity were measured on extracts of Ulmus pumila cortex, which is known as an herbal medicine with antioxidant activity. Mass spectrometry (MS) was performed on the identified radical scavenging active compounds to identify the four components estimated to be procyanidin B2, procyanidin B3, catechin-7-O-β-D-apiofuranoside, and catechin-5-O-β-D-apiofuranoside, respectively. In order to compare the relative contents between extract samples, multiple reaction monitoring (MRM) mode analysis conditions were set for the four compounds in order to examine the possibility of comparing the content of radical scavenging active compounds in Ulmus pumila cortex extract using LC-MS/MS. As a result of the relative content comparison, it was found that the higher the ethanol concentration of the extraction solvent, the higher the content of radical scavenging active compounds. As with the results of measuring the radical scavenging activity of each extract, it was confirmed that the content difference of three of the compounds (all except the compound estimated as procyanidin B3) was not significantly observed in the extracts with an ethanol concentration of 50% or more.

• Korean Journal of Food Science and Technology
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• v.40 no.5
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• pp.510-515
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• 2008

Microwave energy was applied to the extraction of functional catechins from grape seed. The solvent, absolute ethanol, reached the boiling point when exposed for less than 3 min microwave treatment at 100 W. The effects of independent variables in microwave-assisted extraction (MAE), including microwave power (0-160W, $X_1$), ethanol concentration (0-100%, $X_2$) and extraction time (1-5 min, $X_3$), were investigated on each response variable ($Y_n$), and the contents of catechin and its derivatives were determined via response surface methodology, thereby allowing us to predict their optimal extraction conditions. The predicted maximal values of (+)-catechin, procyanidin $B_2$, (-)-epicatechin, and (-)-epicatechin gallate were 137.99, 72.78, 222.38, and 9.59 mg%, respectively, under different MAE conditions. The predicted extraction conditions for maximum catechin responses were as follows: 104.10 W of microwave power, 45.35% of EtOH, and 4.89 min of extraction time for (+)-catechin (137.99 mg%), 133.16 W, 46.16% and 4.49 min for procyanidin $B_2$ (72.78 mg%), 136.00 W, 41.37% and 4.39 min for (-)-epicatechin (222.38 mg%), 143.20 W, 37.51% and 1.88 min for (-)-epicatechin gallate (9.59 mg%), respectively. The contents of (+)-catechin, procyanidin 1B2 and (-)-epicatechin in MAE were similarly influenced by three independent variables, whereas (-)-epicatechin gallate was influenced less profoundly by ethanol concentration and extraction time.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.376.1-376.1
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• 2002

Phytochemical examination of Barks of Ulmus macrocarpa isolated two flavanone, three flavanonol, three flavan 3-ol and one procyanidin compounds. We also determinated the antioxidative activity of these compounds by measuring the radical scavenging effect on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radicals. Three flavan 3-ol (catechin, epicatechin and catechin-7-O-$\beta$-O-xylopyranoside) and procyanidin B1 showed significant antioxidative activity. (omitted)