• Journal of the Korean Wood Science and Technology
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• v.29 no.4
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• pp.97-102
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• 2001

EtOAc extract from the bark of Pinus koraiensis Sieb. et Zucc was isolated by column chromatography which was packed with Sephadex LH-20 or TSK-gel HW-40F. Several stilbene glycosides were identified by $^1H{\cdot}^{13}C$-NMR, HMQC, HMBC and $FAB^+$ MS. Three stilbene glycosides, Z-pinostilbenoside, E-desoxyrhaponticin, and E-resveratroloside, were identified.

• YAKHAK HOEJI
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• v.39 no.1
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• pp.85-93
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• 1995

Acidic and alkaline hydrolysis of diol-type ginseng saponins produced a new glycoside, (20E)-ginsenoside Rh$_{3}$, and its stereoisomer (20Z)-, which were further subjected to alkaline by drolysis to give their aglycones, (20E)- and (20Z)-3$\beta$, 12$\beta$-dihydroxy-dammar-20(22),24-diene. The ratio of stereoisomeric mixtures was estimated to be ca. 5:1 from intensities of the peaks in $^{1}$H- and $^{13}$C-NMR spectra. The $^{1}$H- and $^{13}$C-NMR signals of ginsenoside Rh$_{3}$, which have remained unclarified, were completely assigned by the extensive application of modern NMR techniques.

• Korean Journal of Pharmacognosy
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• v.11 no.1
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• pp.15-23
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• 1980

A new iridoid glucoside was isolated from the whole plant of Ajuga spectabilis Nakai (Jaran-cho; Labiatae). This compound was obtained as white plate-like crystal and named as Jaranidoside. It has a molecular formula $C_{17}H_{26}O_{12}$ and mp $128{\sim}130^{\circ}C$. The structure of the Jaranidoside was assumed from data of chemical reactions and PMR specturum of the compound. To determine the most favorable conformation, informations on the proton coupling and chemical shift were used. Jaranidoside exhibited a stimulating activity on smooth muscle and cardiac muscle. No antimicrobial activity on five microorganism strains was observed.

• Journal of Microbiology and Biotechnology
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• v.34 no.6
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• pp.1270-1275
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• 2024

Human gut bacterium Dorea sp. MRG-IFC3 is unique in that it is capable of metabolizing puerarin, an isoflavone C-glycoside, whereas it shows broad substrate glycosidase activity for the various flavonoid O-glycosides. To address the question on the substrate specificity, as well as biochemical characteristics, cell-free biotransformation of flavonoid glycosides was performed under various conditions. The results showed that there are two different enzyme systems responsible for the metabolism of flavonoid C-glycosides and O-glycosides in the MRG-IFC3 strain. The system responsible for the conversion of puerarin was inducible and comprised of two enzymes. One enzyme oxidizes puerarin to 3"-oxo-puerarin and the other enzyme converts 3"-oxo-puearin to daidzein. The second enzyme was only active toward 3"-oxo-puerarin. The activity of puerarin conversion to daidzein was enhanced in the presence of Mn²⁺ and NAD⁺. It was concluded that the puerarin C-deglycosylation by Dorea sp. MRG-IFC3 possibly adopts the same biochemical mechanism as the strain PUE, a species of Dorea longicatena.

• Korean Journal of Pharmacognosy
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• v.11 no.3_4 s.43
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• pp.141-148
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• 1980

• Applied Biological Chemistry
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• v.19 no.4
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• pp.233-242
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• 1976

In this paper, new methods for the determination of the total and the individual saponin glucosides were proposed. One of them was a colorimetric method following Two-dimensional Thin layer chromatography. And the method employing Thinchrograph TFG-10 or Densitorol DMU-33C followed the separation of the saponins by means of a preparative thin layer chromatography. In accordance with the density of the chromatogram of each saponin, Thinchrogram or Densitogram of the individual saponin fraction was plotted and determined.

• Archives of Pharmacal Research
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• v.19 no.6
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• pp.551-553
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• 1996

A genuine dammarane glycoside, named ginsenoside $Rg_{5}$, has been isolated by repeated column chromatography and preparative HPLC from the MeOH extract of Korean red ginseng (Panax ginseng C.A. Meyer). The chemical structure of ginsenoside$ Rg_{5}$ was determined as $3-O-[{\beta}-D-glucopyranosyl (1{\rightarrow}2)-{\beta}-D-glucopyranosyl]$ dammar-20(22), $24-diene-3{\beta},12{\beta}-diol$ by spectral and chemical methods. The stereostructure of a double bond at C-20(22) of ginsenoside $Rg_{5}$ was characterized as (E) from the chemical shift of C-21 in the $^{13}C-NMR $and a NOESY experiment in the $^{1}H-NMR$.

• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1692-1697
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• 2012

We report a glycoside hydrolase (GH)-118 ${\beta}$-agarase from a strain of Agarivorans, in which we previously reported recombinant expression and characterization of the GH-50 ${\beta}$-agarase. The GH comprised an open reading frame of 1,437 base pairs, which encoded a protein of 52,580 daltons consisting of 478 amino acid residues. Assessment of the entire sequence showed that the enzyme had 97% nucleotide and 99% amino acid sequence similarities to those of GH-118 ${\beta}$-agarase from Pseudoalteromonas sp. CY24, which belongs to a different order within the same class. The gene corresponding to a mature protein of 440 amino acids was inserted, recombinantly expressed in Escherichia coli, and purified to homogeneity with affinity chromatography. It had maximal activity at $35^{\circ}C$ and pH 7.0 and had 208.1 units/mg in the presence of 300 mM NaCl and 1 mM $CaCl_2$. More than 80% activity was maintained after 2 h exposure to $35^{\circ}C$; however, < 40% activity remained at $45^{\circ}C$. The enzyme hydrolyzed agarose to yield neoagarooctaose as the main product. This enzyme could be useful for industrial production of functional neoagarooligosaccharides.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.2
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• pp.242-247
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• 1997

A flavone glycoside was separated from the aerial part of Circium japonicum var ussuriense Kitamura and the effect on cardiovascular system was investigated. The cadiovascular contractility of this compound was observed in the artria and aortae from normal rats. It increased the spontancous beat in right atria and the contractile force in left atria, and caused the contraction of thoracic aortae. For the blood pressure, it had ascending effect. The effective component, which acted on stimulation and contraction in the artria and aortae of rats was fractionated with n-BuOH, separated and identified by column chromatography, UV, IR, $^1H-NMR$ and $^{13}C-NMR$. The chemical structure for this component was determined to be $hispidulin-7-{\alpha}-rhamnopyranosyl(1{\rightarrow}2)-{\beta}-D-glucopyranoside$.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.10a
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• pp.371-374
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• 2004

본 연구는 식물성 에스트로겐인 isoflavone 배당체의 ${\beta}-1,4\;glycoside$ 결합을 ${\beta}-galactosidase$로 분해하여 그 생리적 작용이 더욱 효과적인 aglycone화 하기 위한 조건을 연구하여 기능성식품개발에 응용토록 하는데 목적이 있다. 실험 결과, 모든 ${\beta}-galactosidase$가 ${\beta}-1,4\;glycoside$ 결합의 분해력이 인정되지는 않았으며, 분해 가능성이 인정된 효소를 선택하여 실험한 결과 효소의 함량이 증가함에 따라 aglycone의 성분비율이 증대된 반면, 그 손실률 또한 증대되었고 배양시간이 길수록 aglycone의 성분비율이 증가하였으나 배양초기에 급격한 증가율을 보였으며, pH6과 7, 8에서 유사한 정도의 증가율을 보였고, 온도가 증가함에 따라 aglycone 성분비율이 증가되었지만 $40^{\circ}C$이상에서는 그 손실률이 크게 증가하였다. 결과적으로 판단해 볼 때, isoflavone을 aglycone화 하는데 있어 인체 내 유사조건에서 aglycone의 증가율이 높았으며 최적의 조건과 많은 차이를 나타내지 않았고 그 손실률 또한 최소화된 결과를 나타내어 isofalvone을 적용한 기능성 유제품을 연구하는데 있어 긍정적인 가능성을 보였다.