• Bulletin of the Korean Chemical Society
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• v.31 no.4
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• pp.971-975
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• 2010

Eight hydroxylated stilbene derivatives including resveratrol, desoxyrhapontigenin and piceatannol as potential radical scavenger and tyrosinase inhibitor are synthesized using optimized Wittig-Horner reaction for excellent trans-selectivity in good yields. Antioxidant activity was tested against ABTS radical and tyrosinase inhibitory activity was performed with L-tyrosine as the substrate based on previous procedure with some modification. In general, catecholic stilbenes showed stronger activity against ABTS radical and resorcinolic moiety showed stronger tyrosinase inhibitory activity. Synthetic piceatannol which containing both catecholic and resorcinolic moieties showed the strongest activity in both as ABTS radical scavenger and tyrosinase inhibitor with $IC_{50}$ values of 4.1 and $8.6\;{\mu}M$, respectively.

• YAKHAK HOEJI
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• v.58 no.1
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• pp.12-15
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• 2014

Polygonum cuspidatum which is widely distributed in Korea has been used as treatments of dermatitis, gonorrhea, favus athlete's foot, hyperlipidemia and inflammation in traditional medicine. We examined anti-oxidant and antiinflammatory activity by measuring DPPH radical scavenging activity and the inhibition of IFN-${\gamma}$ and LPS-induced NO production in RAW 264.7 murine macrophage cells. We isolated and characterized resveratrol (1), trans-resveratrol 3-O-${\beta}$-Dglucopyranoside (2). Compounds 1 and 2 showed potent activities compared with L-NMMA ($N^G$-monomethyl-L-arginine). These results suggested that the stilbene compounds isolated from Polygonum cuspidatum might be used as antiinflammatory agents.

• Natural Product Sciences
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• v.27 no.1
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• pp.45-48
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• 2021

One new compound, macasiamenene V (1), and two known stilbenes (2-3) were isolated from Macaranga inermis Pax & K.Hoffm leaves. The structure of 1 was fully assigned based on the information on high-resolution MS and (1D, 2D) NMR spectra. The cytotoxic of compounds 1-3 was evaluated against 4T1 and HeLa cells. Compounds 2-3 showed high activity against HeLa cells with an IC50 value of 1.09 and 0.88 ㎍/mL, respectively.

• Korean Journal of Food Science and Technology
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• v.44 no.2
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• pp.251-256
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• 2012

Stilbenes are known as antioxidants and some of them demonstrate anti-pigmentation activity. The purpose of the present study was to investigate whether two stilbene compounds produced by biotransformation of the extract of $Morus$ $alba$ root show skin irritation and sensitization. In skin irritation test, 1% oxyresveratrol (OXY), and 5% OXY, and 1% oxyresveratrol-3-$O$-glucoside (OXY-3) showed a P.I.I score of 0, 0.04, and 0, respectively. Accordingly, the two stilbenes were evaluated to be virtually 'non-irritant' materials. In a skin sensitization study by GPMT, 1% OXY, 5% OXY, and 1% OXY-3 did not cause edema and erythema at 24 h and 48 h after topical application and exhibited a sensitization score of 0 and a rate of 0%. Consequently, it was confirmed that OXY and OXY-3 had no contact allergic sensitization in GPMT. Therefore, OXY and OXY-3 might be potential candidates as skin-whitening agents without posing any serious side effects.

• Journal of Nutrition and Health
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• v.53 no.6
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• pp.570-582
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• 2020

Purpose: Obesity is a risk factor for various adult diseases such as type 2 diabetes, cardio-cerebrovascular disease, and cancer. With an increasing obesity population worldwide, the prevention of obesity with natural components has emerged as an alternative health care strategy. Ramulus mori (Sangzhi, RM) is widely used as a traditional herbal medicine in East Asia. It contains various phytochemicals, including stilbenes and 2-arylbenzofurans. In this study, we compared the anti-obesity effects of RM extracts and its major stilbene components (mulberroside A [MSA] and oxyresveratrol [ORT]) in high fat diet (HFD)-fed obese mice. Methods: Five week-old, male C57BL/6J mice were grouped into 7 experimental groups: normal diet (ND), HFD, HFD + 1% RM water extracts (MW), HFD + 0.1% MSA, HFD + 1% RM ethanol extracts (ME), HFD + 0.1% ORT, and HFD + 1% Garcinia cambogia extracts (GC) as a positive control. All mice were fed experimental diet for 13 weeks. Results: Compared to the HFD group, total body weight and weekly body weight gain were significantly decreased in the ME, ORT, and GC groups. Glucose tolerance level was significantly decreased in all experimental groups, whereas plasma insulin level was decreased in MSA, ME, ORT and GC groups. Plasma glucose, triglyceride (TG), and total cholesterol levels were significantly decreased, whereas high-density lipoprotein cholesterol levels were increased in the MSA, ORT, and GC groups. Hepatic TG accumulation was also significantly decreased in the MSA, ME, ORT, and GC groups. Adipose tissue weight and size of adipocytes were significantly decreased in the MSA, ME and ORT groups, and were comparable to values obtained in the GC group. The levels of adiponectin and SREBP1c mRNA expressions were increased in the ORT and GC groups. Conclusion: These results indicate that ME, ORT and MSA exert significant anti-obesity effect, and have the potential to be developed as a weight control ingredient of functional foods.

• Korean Journal of Pharmacognosy
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• v.40 no.4
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• pp.257-279
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• 2009

Plants of genus Dioscorea have long been served as important carbohydrate-stuffed foods in the tropical and subtropical regions, and utilized as traditional herb medicines to enhance digestive function, improve anorexia, and treat diarrhea in oriental countries. It is known that around 600 species of Dioscorea are distributed in the world including 107 species in Asia, but actually utilized Dioscorea species are restricted to small numbers. Phytochemical investigations for Dioscorea species have revealed a number of chemical components such as sapogenins, saponins, phenanthrenes, stilbenes, diterpenes and purine derivatives. According to recent pharmacological studies, Dioscorea species possess significant antioxidant, antibacterial and anti-inflammatory activities as well as anticancer, antidiabetic, cholesterol-lowering and hypolipidemic effects. Here, seven Dioscorea species (D. batatas, D. japonica, D. bulbifera, D. opposita, D. tokoro, D. nipponica and D. alata), mainly distributed and used in Korea, China, and Japan, are reviewed to provide their botanical, phytochemical and pharmacological properties were described.

• 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.

• Journal of Microbiology and Biotechnology
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• v.28 no.7
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• pp.1105-1111
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• 2018

The flavin-dependent monooxygenase Sam5 was previously reported to be a bifunctional hydroxylase with coumarate 3-hydroxylase and resveratrol 3'-hydroxylase activities. In this article, we showed the Sam5 enzyme has 3'-hydroxylation activities for methylated resveratrols (pinostilbene and pterostilbene), hydroxylated resveratrol (oxyresveratrol), and glycosylated resveratrol (piceid) as substrates. However, piceid, a glycone-type stilbene used as a substrate for bioconversion experiments with the Sam5 enzyme expressed in Escherichia coli, did not convert to the hydroxylated compound astringin, but it was converted by in vitro enzyme reactions. Finally, we report a novel catalytic activity of Sam5 monooxygenase for the synthesis of piceatannol derivatives, 3'-hydroxylated stilbene compounds. Development of this bioproduction method for the hydroxylation of stilbenes is challenging because of the difficulty in expressing P450-type hydroxylase in E. coli and regiospecific chemical synthesis.

• 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).

• Natural Product Sciences
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• v.25 no.3
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• pp.244-247
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• 2019

A new isoprenylated stilbene, flavestinK (1) together with two known isoprenylated stilbenes, flavestin B (2), flavestin G (3), and two isoprenilated flavanones, 4-O-methyl-8-isoprenylnaringenin (4) and 8-isoprenyl-5,7-dihydroxyflavanone (5) were isolated from the leaves of Macaranga recurvata Gage. All of the structures have been determined based on HRESIMS, 1D and 2D NMR spectral data. All of the isolated compounds were evaluated for their cytotoxicity against three human cancer cells (HeLa, T47D and WiDr). Compound 1 showed higher activity than doxorubicin against HeLa cells with $IC_{50}$ value of $13.1{\mu}g/mL$.