• 생약학회지
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• 제35권2호통권137호
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• pp.157-163
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• 2004

Twenty two polyphenols containing ten gallotannins, seven ellagitannins, two phenylpropanoids and three stilbenes isolated from the higher plants were tested inhibitory effects on melanogenesis in cultured B-16 mouse melanoma cell lines. Among the tested samples, 1-desgalloyleugeniin exhibited the most potent inhibitory effect on melanogenesis in cultured cell lines.

• Bulletin of the Korean Chemical Society
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• 제31권8호
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• pp.2175-2179
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• 2010

Quantum mechanical properties of unsymmetrical and unfunctionalized trans-stilbene derivatives 1-3, which had been prepared by solid-phase parallel syntheses, were characterized using mPW1PW91/6-311G(d,p) (hybrid HF-DF) calculations. The total electronic energies, normal vibrational modes, Gibbs free energies, and HOMOs and LUMOs of sixteen different structures from three different groups were analyzed. The energy differences between the HOMOs and LUMOs of the various unsymmetrical trans-stilbenes are in accord with the maximum absorption peaks of the experimental UV spectra of 1-3. The calculated normal vibrational modes of 21 were comparable with its experimental IR spectrum. The $\pi$-conjugation in the para-connected biphenyl group of 2 is better than the one in the metaconnected biphenyl group on the shorter side of 3.

• Biomolecules & Therapeutics
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• 제17권1호
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• pp.79-85
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• 2009

Polyphenolic compounds are reported to have various pharmacological activities such as anti-oxidative, anti-cancerous, anti-inflammatory and anti-aging effects. Although numerous papers explore their functional roles in many different cellular actions, not many studies handle their structural features in anti-inflammatory responses. In this study, therefore, we examined structural role of substituted transstilbenes in their NO inhibitory and NF-${\kappa}B$ suppressive activities. Of 10 compounds tested, 4 compounds (cinnamic acid, resveratrol, piceatannol and curcumin) displayed NO inhibitory activities in a dose-dependent manner. Similarly, these compounds blocked LPS-induced cytotoxicity of RAW264.7 cells. All NO inhibitory compounds also inhibited $I{\kappa}B{\alpha}$ phosphorylation, a hallmark for NF-${\kappa}B$ activation. However, these inhibitory compounds exhibited distinct suppressive pattern in tumor necrosis factor (TNF)-${\alpha}$- or phorbol-12-myristate-13-acetate (PMA)-induced NF-${\kappa}B$ and AP-1 activation. According to structure-activity relationship study, polarity and size of ring B seem to be important for diminishing NO production. Therefore, our data suggest that substituted trans-stilbenes can be developed as novel anti-inflammatory drug or further developed as lead compounds for another improvement.

• Bulletin of the Korean Chemical Society
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• 제9권3호
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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$^-$:

• 대한약침학회지
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• 제25권3호
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• pp.199-208
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• 2022

Objectives: In recent decades, the trend for treating diabetes mellitus (DM) has shifted toward alternative medicines that are obtained from plant sources. Existing literature suggests that phenolic compounds derived from plants possess promising health-promoting properties. This study aimed to discuss the role of plant-derived phenolic compounds in the effective treatment and management of diabetes. Methods: Information about plant secondary metabolites, phenolic compounds, and their role in the treatment and management of diabetes was collected from different databases, such as Pubmed, ScienceDirect, Scopus, and Google Scholar. Keywords like secondary metabolites, phenolic compounds, simple phenol, flavonoids, lignans, stilbenes, and diabetes were searched. Research and review articles with relevant information were included in the study. Results: Anti-diabetic studies of the four major classes of phenolic compounds were included in this review. The plant-derived phenolic compounds were reported to have potent anti-diabetic activities. However, each class of phenolic compounds was found to behave differently according to various mechanisms. Conclusion: The obtained results suggest that phenolic compounds derived from natural sources display promising anti-diabetic activities. Based on the available information, it can be concluded that phenolic compounds obtained from various natural sources play key roles in the treatment and management of diabetes.

• Journal of Photoscience
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• 제7권1호
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• pp.35-37
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• 2000

Photolysis of $\alpha$-(o-alkylphenyl) indanones resulted in $\alpha$-cleavage followed by disproportionation to form E-and Z- ortho-formyl stilbenes. No evidences of hydrogen abstraction reactions were collected from these indanones. The minimum rate constant of $\alpha$-cleavage in the $\alpha$-(o-alkylphenyl) indanones was estimated to be 5.5$\times$10$^{10}$ s$^{-1}$ .

• 원예과학기술지
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• 제30권5호
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• pp.493-500
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• 2012

포도 잎에서 병 발생을 경감하기 위한 수단으로 자외선의 활용 가능성을 확인하기 위하여, 자외선을 조사한 포도 잎에서 stilbene 화합물의 함량 변화와 Botrytis cinerea 생장의 차이를 조사하였다. 자외선의 조사는 포도 잎에서 resveratrol, piceatannol, piceid의 함량을 크게 증가시켰으며, 특히 resveratrol과 piceid는 B. cinerea의 포자 발아와 균사 생장을 억제하는 효과를 보였다. 자외선 조사에 의해 포도 잎에 축적되는 resveratrol과 piceid의 농도는 B. cinerea의 생장을 억제하기에 충분할 것으로 생각되며 자외선을 조사한 포도 잎에 B. cinerea의 포자를 접종하였을 때 괴사 반점의 형성이 억제되는 것으로 나타났다. 그러나 stilbene 화합물은 체내 이동성이 거의 없고 자외선에 직접 노출된 잎에서만 함량이 증가하므로 병 발생 경감의 수단으로 자외선을 활용하기 위해서는 수관 전체에 자외선을 균일하게 조사하는 방법의 도입이 필요해 보인다.

• Journal of Microbiology and Biotechnology
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• 제20권9호
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• pp.1295-1299
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• 2010

Recently, recombinant Streptomyces venezuelae has been established as a heterologous host for microbial production of flavanones and stilbenes, a class of plant-specific polyketides. In the present work, we expanded the applicability of the S. venezuelae system to the production of more diverse plant polyketides including flavones and flavonols. A plasmid with the synthetic codon-optimized flavone synthase I gene from Petroselium crispum was introduced to S. venezuelae DHS2001 bearing a deletion of the native pikromycin polyketide synthase gene, and the resulting strain generated flavones from exogenously fed flavanones. In addition, a recombinant S. venezuelae mutant expressing a codon-optimized flavanone $3{\beta}$-hydroxylase gene from Citrus siensis and a flavonol synthase gene from Citrus unshius also successfully produced flavonols.

• Natural Product Sciences
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• 제20권2호
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• pp.91-94
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• 2014

Column chromatographic separation of the MeOH extract from the tubers of Bletilla striata yielded seven phenolic components including four phenanthrenes, 3,7-dihydroxy-2,4-dimethoxyphenanthrene (1), 3,7-dihydroxy-2,4,8-trimethoxyphenanthrene (2), 9,10-dihydro-4,7-dimethoxyphenanthrene-2,8-diol (3), and 9,10-dihydro-1-(4'-hydroxybenzyl)-4,7-dimethoxyphenanthrene-2,8-diol (4) and three stilbenes, gigantol (5), 3',4"-dihydroxy-5',3",5"-trimethoxybibenzyl (6), and batatasin III (7). Their structures were determined on the basis of NMR spectroscopic data. Among them, compound 2, 3, and 6 were reported for the first time from this plant. The isolated compounds (1-7) were tested for cytotoxicity against four human tumor cell lines in vitro using a Sulforhodamin B bioassay.

• Preventive Nutrition and Food Science
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• 제8권2호
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• pp.200-218
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• 2003

Phenolic compounds in food and plant materials belong to the simple phenols, phenolic acids, coumarins, flavonoids, stilbenes, tannins, lignans and lignins, all of which are considered as secondary plant metabolites. These compounds may be synthesized by plants during normal development or in response to stress conditions. Phenolics are not distributed uniformly in plants. Insoluble phenolics are components of cell walls while soluble ones are present in vacuoles. A cursory account of phenolics of cereals, beans, pulses, fruits, vegetables and oilseeds is provided in this overview. The information on the bioavailability and absorption of plant phenolics remains fragmentary and diverse. Pharmacological potentials of food phenolics ave extensively evaluated. However, there are many challenges that must be overcome in order to fully understand both the function of phenolics in plant as well as their health effects.