• Preventive Nutrition and Food Science
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• v.7 no.4
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• pp.447-450
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• 2002

Previously, a methanol extract from seeds of Paeonia lactiflora was shown to have a potent inhibitory activities against tyrosinase and soybean lipoxygenase (SLO). Seven stilbenes, trans-resveratrol-4-Ο-$\beta$-D-glucoside, trans resveratrol, trans-$\varepsilon$-viniferin, cis-$\varepsilon$-viniferin, gnetin H, suffruticosol A and B were isolated from the seeds as active principles for inhibition of the enzymatic activity. Among them, the resveratrol trimer, gnetin H exhibited the most potent inhibitory activities against tyrosinase and SLO, respectively. Additionally, the resveratrol dimers, trans-$\varepsilon$-viniferin and cis-$\varepsilon$-viniferin exhibited significant inhibitory activity against the two oxidative enzymes. Meanwhile, three other stilbene derivatives, such as trans-resveratrol, suffruticosol A and suffruticosol B had also weak inhibition activity. The least inhibitory activity was observed in transresveratrol-4-Ο-$\beta$-D-glucoside. These results suggest that resveratrol dimers and trimer in the seeds of Paeonia lactiflora are potentially useful therapeutic agents against pathological disorders such as hyperpigmentation and inflammation.

• YAKHAK HOEJI
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• v.27 no.1
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• pp.37-43
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• 1983

The rhizome of Polygonum sachalinense Fr. Schm. (=Reynoutria sachalinensis Nakai, Polygonaceae) has been used as "Polygoni Rhizoma" (Hu Zhang) in the Orient as laxatives, diuretics and for treatment of suppurative dermatitis, gonorrhoea, favus and athlete's foot. From the methanolic extract of the dried rhizome physcion, emodin, emodin-8-O-$\beta$-D-glucoside as anthraquinone derivatives and .betha.-sitosterol glucoside were isolated and identified. Stilbene derivatives which have antibacterial and antifungal activities were also isolated.

• Bulletin of the Korean Chemical Society
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• v.23 no.3
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• pp.528-530
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• 2002

• Proceedings of the PSK Conference
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• 2000.10a
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• pp.133.1-133.1
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• 2000

• Bulletin of the Korean Chemical Society
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• v.9 no.3
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• pp.167-171
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• 1988

Formation of intermolecular charge-transfer complexes between 7,7,8,8-tetracyanoquinodimethane (TCNQ) and two different series of stilbene derivatives has been studied spectroscopically at $25^{\circ}$C in 1,2-dichloroethane. The compounds of Series I include stilbene and derivatives which have fused phenyl rings on one end of the central ethylene structure and a phenyl ring on the other end. The other Series, II, is comprised of stilbenes which have various para substituents on one of the two phenyl rings. The equilibrium constant, $K_c^{AD}$ and the molar extinction coefficient, ${\varepsilon}_{\lambda}^{AD}$, were determined using the Scott equation. The values of the charge-transfer transition frequency, ${\vu}_AD$ and $K_c{AD}$ correlated well respectively with the ionization potentials of the fused rings of Series Ⅰ or of the compounds of Series II and with the values of ${\sigma}_p$, the Hammett constants of the Series II substituents. trans-4-N,N-Dimethylaminostilbene and trans-4-nitrostilbene were found to be able to participate in electron transfer reaction with TCNQ forming the corresponding anion radical, TCNQ$^-$:

• Archives of Pharmacal Research
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• v.28 no.9
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• pp.1027-1030
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• 2005

The antidiabetic-activity-guided fractionation and isolation of the $80\%$ EtOH extracts obtained from cultivated Korean Rhubarb rhizomes (Rheum undulatum, Polygonaceae) led to the isolation and characterization of one stilbene, desoxyrhapontigenin(1) and two anthraquinones, emodin (2) and chrysophanol (3). Their structures were established by chemical and spectroscopic methods. Compounds 1, 2, and 3 inhibited postprandial hyperglycemia by 35.8, 29.5, $42.3\%$, respectively.

• Korean Journal of Pharmacognosy
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• v.36 no.4 s.143
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• pp.257-262
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• 2005

This study was carried out to obtain the basic information that can be used to index rhubarbs in six regions of China and Korea. The anthraquinone and stilbene contest in various rhubarb produced in th different area were quantitatively analysed by HPLC. The average of sennoside A content of the Chinghai rhubarb was higher than that of the other palmata rhubarbs(high-quality rhubarbs) produced in China. As a result, the order of the sennoside A content was 1) Chinghai rhubarb, 2) Tsuchan rhubarb, 3)Kansu rhubarb 4) Neimenggu rhubarb. On the other hand, the total stilbenes content of each of the cultivated Korean rhubarb(Rheum undulatum) were higher than that of the Chinese rhapontica rhubarb(low-quality rhubarbs).

• Journal of Applied Biological Chemistry
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• v.44 no.4
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• pp.199-201
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• 2001

A phenolic substance was isolated from the bark of Pinus koraiensis. It was identified to be pinostilbenoside. Its anti-$LTD_4$ activity was evaluated using isolated guinea pig trachea, and its half maximal bronchodilating activity ($EC_{50}$) was $593{\pm}56{\mu}g{\cdot}ml^{-1}$. Because it is not known that stilbene derivatives possess anti-asthmatic activity through $LTD_4$ antagonism, here we report the result.

• Archives of Pharmacal Research
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• v.22 no.4
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• pp.401-403
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• 1999

In continued studies on cultivated Korean rhubarb rhizomes (Rheum undulatum), three known stillbenes (desoxyrhapontigenin, rhapontigenin, piceatannol) have been screened for activity on blood platelet aggregation. Both rhapontigenin and desoxyrhapontigenin exhibited strong inhibition on the aggregation induced by arachidonic acid collagen. However, piceatannol did not show inhibition. These inhibitory effects may partially contribute to anti-blood stagnancy activity of rhubarb.

• Proceedings of the PSK Conference
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• 2003.10a
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• pp.88-88
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• 2003

The syntheses of different types of stilbenoid libraries have been studied recently. In these courses, the screening of the generated natural product-mimic focused libraries led to the identification of the novel lead compounds for human cytochrome P450 (CYP) lAs, melanin production, and sortase A. A library of trans-stilbene derivatives was prepared through a new efficient solution pahse synthetic pathway and their inhibitory activities were evaluated on human cytochrome P450s(CYP) 1A1, 1A2, and 1B1 to find a potent and selective CYP1 inhibitor. (omitted)