• 약학회지
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• 제35권5호
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• pp.432-437
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• 1991

A mixture of 20(R)- and 20(S)-ginsenoside Rg$_{3}$ was obtained under mild acidic hydrolysis from protopanaxadiol saponins, ginsenosides Rb$_{1}$, Rb$_{2}$, Rc and Rd. The product was acetylated to give the peracetates, which were further converted into 20(R)-ginsenoside Rg$_{3}$, 20(S)-ginsenoside Rg$_{3}$, 20(R)-ginsenoside Rh$_{2}$ and 20(S)-ginsenoside Rh$_{2}$ by the direct alkaline treatment depending upon two kinds of temperature conditions respectively. The structure and physicochemical properties of a prosapogenin, 20(R)-ginsenoside Rh$_{2}$, were investigated.

• Journal of Ginseng Research
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• 제15권3호
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• pp.188-191
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• 1991

The mild hydrolysis of ginsenosie Re with 50% acetic acid gave a prosapogenin mixture, 20(R)- and 20(S)-ginsenoside Rg2. The products were acetylated to give the peracetates, which were further converted into 20(R)- and 20(S)-ginsenoside Rh1 by the alcoholic alkaline treatment.

• Journal of Microbiology and Biotechnology
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• 제27권7호
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• pp.1233-1241
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• 2017

The ginsenoside Rh2 has strong anti-cancer, anti-inflammatory, and anti-diabetic effects. However, the application of ginsenoside Rh2 is restricted because of the small amounts found in Korean white and red ginsengs. To enhance the production of ginsenoside Rh2-MIX (comprising 20(S)-Rh2, 20(R)-Rh2, Rk2, and Rh3 as a 10-g unit) with high specificity, yield, and purity, a new combination of enzymatic conversion using the commercial enzyme Viscozyme L followed by acid treatment was developed. Viscozyme L treatment at pH 5.0 and $50^{\circ}C$ was used initially to transform the major ginsenosides Rb1, Rb2, Rc, and Rd into ginsenoside F2, followed by acid-heat treatment using citric acid 2% (w/v) at pH 2.0 and $121^{\circ}C$ for 15 min. Scale-up production in a 10-L jar fermenter, using 60 g of the protopanaxadiol-type ginsenoside mixture from ginseng roots, produced 24 g of ginsenoside Rh2-MIX. Using 2 g of Rh2-MIX, 131 mg of 20(S)-Rh2, 58 mg of 20(R)-Rh2, 47 mg of Rk2, and 26 mg of Rh3 were obtained at over 98% chromatographic purity. Then, the anti-cancer effect of the four purified ginsenosides was investigated on B16F10, MDA-MB-231, and HuH-7 cell lines. As a result, these four rare ginsenosides markedly inhibited the growth of the cancer cell lines. These results suggested that rare ginsenoside Rh2-MIX could be exploited to prepare an anti-cancer supplement in the functional food and pharmaceutical industries.

• 약학회지
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• 제45권4호
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• pp.328-333
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• 2001

Ginsenoside Rh$_2$, a minor glycoside constituent of the red ginseng is known as an unique antitumor compound. Several attempts to prepare it in a large scale including semisynthesis from betulafolientriol, an 3-epimer of 20(S)-protopanaxadiol, has been reported. We have previously reported a synthesis of ginsenoside Rh$_2$from 20(S)-protopanaxadiol obtained by alkaline hydrolysis of total ginsenoside. The regioselective synthesis of this compound was achieved by protection of 12-OH group.

• 약학회지
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• 제38권4호
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• pp.425-429
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• 1994

The genuine aglycone, 20(S)-protopanaxadiol, obtained from the leaves of Panax ginseng as a result of direct alkaline treatment was isolated and characterized by spectroscopic evidences. The study on the yield of genuine aglycone which is produced from the treatment of some kinds of alkali was carried out. $Ginsenoside-Rh_2$ was synthesized by conjugation of 2,3,4,6-tetra-O-acetyl-${\alpha}$-D-glucopyranosyl bromide to 20(S)-protopanaxadiol in the presence of silver carbonate and cadmium cabonate. The preparation of $ginsenoside-Rh_2$ by this method is a new one which the yield of this saponin can be improved in the mild condition.

• Applied Biological Chemistry
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• 제38권2호
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• pp.184-189
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• 1995

인삼의 다이올계 조사포닌 분획으로 부터 및 단계의 화학반응을 이용하여 (20S)-ginsenoside $Rh_2$ 및 그 입체이성체인 (20R)-ginsenoside $Rh_2$를 제조하였다. 또한 DEPT, $^1H-^1H$ COSY, HMQC, HMBC 및 NOESY와 같은 NMR 기법을 이용하여 두 화합물의 $^1H-NMR$과 $^{13}C-NMR$의 signal들을 완전히 동정하였다.

• Journal of Ginseng Research
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• 제20권1호
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• pp.111-112
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• 1996

The chemical shifts of C-21 and C-23 in the $^{13}C$-NMR for (20R)-protopanaxatriol, (20R)-ginsenoside $Rh_1$ and (20R)-ginsenoside $Rg_3$ were revised by employing some extensive 2D-NMR techniques.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 1984년도 학술대회지
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• pp.159-168
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• 1984

생약의 화학적 특성에 대한 계속적인 연구가 이루어짐에 따라 우리는 홍삼 및 백삼의 화학성분을 상대적으로 규명하였다. 홍삼은 극성이 약한 분획에서 5개의 새로운 배당체(20R-ginsenoside $Rg_{2},\;Rh_{1};20R$, 20S-ginsenoside $Rg_{3}; ginsenoside\;Rh_{2}$와 새로운 아세칠렌 화합물(Panaxytriol)을 함유하는 특징적인 성분들이 gins - enoside Rh1, Rg2와 함께 분리되었다. ginsenoside Rh2는 배양된 종양세포에 대해 세포독소 효과를 보여주었다. 백삼은 수용성 분획에서 특징적인 성분이 있는 것으로 밝혀졌으며, 여기에서 malonly-ginsenosides Rb1, Rb2, Rc 및 Rd로 명명된 새로운 배당체 성분이 분리되었다. Malona-ginsenosides는 백삼에서는 주요한 배당체이지만, 홍삼에서는 검출되지 않았다.

• Natural Product Sciences
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• 제10권6호
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• pp.347-352
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• 2004

When saponin extracts of dried ginseng and red ginseng were anaerobically incubated with human intestinal microflora, these extracts were metabolized to compound K and ginsenoside $Rh_2$, respectively. However, when these extracts were incubated with commercial lactic acid bacteria, these did not metabolize these ginsenosides to compound K or ginsenoside $Rh_2$. Among some intestinal bacteria isolated from human feces, Bacteroides C-35 and C-36 transformed these saponin extracts to compound K and ginsenoside $Rh_2$, respectively. These bacteria also transformed water extracts of dried ginseng and red ginseng to compound K and ginsenoside $Rh_2$, respectively, similarly with that of the saponin extracts. Among transformed ginsenosides, compound K and 20(S)-ginsenoside $Rh_2$ exhibited the most potent cyotoxicity against tumor cells.

• Journal of Ginseng Research
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• 제41권4호
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• pp.496-502
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• 2017

Background: Ginsenosides are the major components of Panax ginseng Meyer, an herbal medicine used for the treatment of various diseases. Different ginsenosides contribute to the biological properties of ginseng, such as antimicrobial, anticancer, and immunomodulatory properties. In this study, we investigated the antiviral effects of 15 ginsenosides and compound K on gammaherpesvirus. Methods: The antiviral activity of ginsenosides was examined using the plaque-forming assay and by analyzing the expression of the lytic gene. Results: 20(R)-Ginsenoside Rh2 inhibited the replication and proliferation of murine gammaherpesvirus 68 (MHV-68), and its half-maximal inhibitory concentration ($IC_{50} $) against MHV-68 was estimated to be $2.77{\mu}M$. In addition, 20(R)-ginsenoside Rh2 inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced lytic replication of human gammaherpesvirus in the Kaposi's sarcoma-associated herpesvirus (KSHV)-positive cell line BC3. Conclusion: Our results indicate that 20(R)-ginsenoside Rh2 can inhibit the replication of mouse and human gammaherpesviruses, and thus, has the potential to treat gammaherpesvirus infection.