• Journal of the Korean Chemical Society
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• v.55 no.6
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• pp.926-931
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• 2011

A series of complexes of the type [$ML_2Cl_2$], where L=2-(o-anisylidene-2'-imino) amino benzimidazole (AIAB) and 2-(furfurylidene imino) amino benzimidazole (FIAB), M=Cu(II), Co(II), Ni(II) and Zn(II), have been synthesized and characterized on the basis of elemental analysis, thermal analysis, molar conductivity, magnetic moment, electronic, infrared, $^1H$-NMR spectral studies. The results are in consistent with bidentate chelation of ligand with azomethine nitrogen and ring nitrogen donors. All these Schiff bases and their complexes have also been screened for their antibacterial (Bacillus subtilis, Bacillus stearothermophilus, Escherichia coli and Salmonella typhi) and antifungal activities (Aspergillus niger and Aspergillus flavus).

• 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.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.970-975
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• 1998

Eighty percent of acetone extract were isolated from the leaves of Korean Oolong tea using Sephadex LH-20, MCI-gel, Fuji gel. The compound reacted the red and the blue with anisaldehyde and $FeCl_3$, respectively. Instrumental analysis of the derivatives of this compound showed that the chemical structure was decided to $epicatechin-(4{\beta}{\rightarrow}8)-epigallocatechin-3-O-gallate$ as a kind of dimeric proanthocyanidine, that bound with -(-)epicatechin and -(-)epigallocatechin-3-O-gallate, at the upper and the lower, respectively. Considering inhibition effect on xanthin oxidase by 62% levels at $50{\;}{\mu}mole$, this compound showed a possibility to be used as a new material for functional food.