• Applied Chemistry for Engineering
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• v.32 no.2
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• pp.132-138
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• 2021

This review investigated the types of physiologically active substances isolated and extracted from Pinus densiflora and koraiensis native to Republic of Korea, and the current status of research on their effectiveness and industrial use. They contain various bioactive substances including essential oils, polyphenols, resins, and stilbene derivatives. In recent, physiological activities such as antioxidant, anti-inflammatory, antibacterial, cataract prevention, and neuroprotection from extracts of Pinus densiflora and koraiensis have been identified by domestic researchers. The extracts have been used in different industrial fields like food, health functional foods, cosmetics, and household goods, but the high proportion of them is industrially made from exotic species. Therefore, various studies on industrial applicability are needed due to the lack of cases in which the activity is applied to actual products, with respect to the effects that have been scientifically recognized.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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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.

• 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.13 no.4
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• pp.145-152
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• 1982

Three species of genus Polygonum, namely P. cuspidatum, P. sachalinense and P. ellipticum are distributed in Korea. Polygonum ellipticum Migo is a perennial herb in Polygonaceous plants. The root of the plant (Polygoni Rhizoma, 'Ho-jang') have been used as laxative, diuretic and for the treatment suppurative dermatitis in the oriental medicine. As the part of the study for the comparison of the three species in their components, the authors attempted to isolate the anthraquinones and stilbene derivative from the rhizome of P. ellipticum. The methanolic extract of dried rhizome of this plant was fractionated into ether soluble and insoluble fraction and each fraction was applied to column chromatography to isolate above mentioned components. Anthraquinone derivatives were isolated first; comp. I, mp $204{\sim}205^{\circ}$ (physcion), comp. II, mp $254{\sim}255^{\circ}$ (emodin), comp. IV, mp $191{\sim}192^{\circ}$ $(emodin-8-O-{\beta}-D-glucoside)$ and comp. III, mp $280{\sim}282^{\circ}$ $({\beta}-sitosterol-glucoside)$. They were identified by chemical properties and UV, IR and NMR spectra and by the direct comparison with authentic samples. Stilbene derivative was isolated secondly; comp. V, mp $255{\sim}256^{\circ}$ which was reported to possess antibacterial and antifungal activities.

• Molecules and Cells
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• v.38 no.4
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• pp.318-326
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• 2015

We previously reported that the SbROMT3syn recombinant protein catalyzes the production of the methylated resveratrol derivatives pinostilbene and pterostilbene by methylating substrate resveratrol in recombinant E. coli. To further study the production of stilbene compounds in E. coli by the expression of enzymes involved in stilbene biosynthesis, we isolated three stilbene synthase (STS) genes from rhubarb, peanut, and grape as well as two resveratrol O-methyltransferase (ROMT) genes from grape and sorghum. The ability of RpSTS to produce resveratrol in recombinant E. coli was compared with other AhSTS and VrSTS genes. Out of three STS, only AhSTS was able to produce resveratrol from p-coumaric acid. Thus, to improve the solubility of RpSTS, VrROMT, and SbROMT3 in E. coli, we synthesized the RpSTS, VrROMT and SbROMT3 genes following codon-optimization and expressed one or both genes together with the cinnamate/4-coumarate:coenzyme A ligase (CCL) gene from Streptomyces coelicolor. Our HPLC and LC-MS analyses showed that recombinant E. coli expressing both ScCCL and RpSTSsyn led to the production of resveratrol when p-coumaric acid was used as the precursor. In addition, incorporation of SbROMT3syn in recombinant E. coli cells produced resveratrol and its mono-methylated derivative, pinostilbene, as the major products from p-coumaric acid. However, very small amounts of pterostilbene were only detectable in the recombinant E. coli cells expressing the ScCCL, RpSTSsyn and SbROMT3syn genes. These results suggest that RpSTSsyn exhibits an enhanced enzyme activity to produce resveratrol and SbROMT3syn catalyzes the methylation of resveratrol to produce pinostilbene in E. coli cells.

• Korean Journal of Pharmacognosy
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• v.17 no.1
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• pp.73-77
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• 1986

Anthraquinones, physcion (I), mp $204{\sim}205^{\circ}$ and emodin (II), mp $254{\sim}255^{\circ}$, and $emodin-8-O-{\beta}-{_D}-glucoside$ (IV), mp $191{\sim}192^{\circ}$ together with ${\beta}-sitosterol$ glucoside (III), mp $280{\sim}282^{\circ}$ were isolated from the roots of Polygonum ellipticum Migo and P. sachalinense Fr. Schm. (Polygonaccae). Stilbene derivatives, 3,5,4'-trihydroxystibene (V), mp $258{\sim}260^{\circ}$ and $3,5,4'-trihydroxystilbene-3-O-{\beta}-{_D}-glucoside$ (VI), mp $142{\sim}144^{\circ}$ were also isolated.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05a
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• pp.92-92
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• 2002

Recently we have reported that various hydroxystilbenes show strong inhibition of human P450 1 activity. A series of synthetic trans-stilbene derivatives were prepared and their inhibitory potentials were evaluated with the bacterial membrane of recombinant human P450 1A1, 1A2 or 1B1 coexpressed with human P450/NADPH-450 reductase to find new candidates for cancer chemoprevention.(omitted)

• Journal of the Korean Wood Science and Technology
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• v.37 no.5
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• pp.474-479
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• 2009

Pinus koraiensis inner bark was collected and extracted with 95% ethanol. The extracts were concentrated and then sequentially fractionated using n-hexane, $CH_2Cl_2$, EtOAc, and $H_2O$ to be freeze dried. A portion of EtOAc fraction (6.6 g) was chromatographed on a Sephadex LH-20 column using aqueous methanol to isolate (+)-catechin (1), (-)-epicatechin (2), and trans-pinostilbenoside (3). Resveratrol (4) and trans-pinostilbene (5) were isolated by column chromatography using EtOH-hexane mixture after purification with aqueous methanol. The structures of these stilbenosides and flavans were characterized by spectroscopic tools using NMR and MS.

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3655-3659
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• 2011

The hydrogenolysis of polymer-bound arenesulfonates by 2-propylmagnesium chloride was performed through reductive cleavage of the C-S bond in the presence of a nickel catalyst. The reaction underwent in the highest efficiency by adding 15 equiv of the nucleophile in two additions with $dppfNiCl_2$ in THF. Various unfunctionalized naphthalene, biphenyl, and stilbene derivatives were produced in good yields by the traceless sulfonate linker system at room temperature.

• Bulletin of the Korean Chemical Society
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• v.1 no.2
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• pp.68-70
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• 1980

1,4,5,8-Tetraazaphenanthrene, a new tetraazaheteroaromatic compound, has been synthesized photochemically in 90 % yield and quantum yield of $5.1{\times}10^{-2}$ from dilute benzene solutions of 1,2-bispyrazyl ethylene(BPE) in the presence of oxygen as an oxidant. Iodine was not appropriate oxidant because of strong complexing with BPE and also enhanced intersystem crossing of BPE and thereby decreasing the photocyclization of BPE. Salt effect, solvent effect, and quenching and sensitization studies on the photocyclization of BPE have shown that ($^l(n, {\pi}^*$) is the reactive state for the cyclization in comparison to ($^1{\pi}, {\pi}^*$) state for the ordinary stilbene derivatives.