• Natural Product Sciences
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• 제12권3호
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• pp.138-143
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• 2006

Our continuing interest on Garcinia and Mesua species has led us to carry out a detail study on the chemistry of the root bark of Garcinia mangostana (Guttiferae) since this part of the plant has not been investigated before, and the strm bark of Mesua corneri (Guttiferae) an uninvestigated species. This study has yielded six xanthones, ${\alpha}-mangostin$ (1), ${\beta}-mangostin$ (2), ${\gamma}-mangostin$ (3), garcinone-D (4), mangostanol (5) and gartanin (6) from Garcinia mangostana and two xanthones rubraxanthone (7) and inophyllin B (8) from Mesua corneri. Structural elucidations were achieved using $^1H,\;^{13}C$ NMR and MS data. The crude hexane and chloroform extracts of the root bark of Garcinia mangostana and the hexane extract of the stem bark of Mesua corneri were found to be active against CEM-SS cell lines with $IC_{50}$ values less than $30\;{mu}g/ml$. Moreover, ${\gamma}-mangostin$ gave a very low $LC_{50}$ value of $4.7\;{mu}g/ml$ while rubraxanthone gave an $LC_{50}$ value of $5.0\;{mu}g/ml$ indicating these two compounds to be potential lead compounds for anti-cancer activity against the CEM-SS cell line. This paper reports the isolation and identification of these compounds as well as bioassay data for the crude extracts, ${\gamma}-mangostin$ and rubraxanthone.

• 공업화학
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• 제4권2호
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• pp.381-392
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• 1993

탄소수 10~18 범위에 있는 고급지방산 즉, decanoic acid, dodecanoic acid, tetradecanoic acid, hexadecanoic acid 및 octadecanoic acid 등을 $SO_3$-dioxane complex로 ${\alpha}$-술폰화 한 다음, dodecanol-1에 에틸렌옥사이드를 5몰, 10몰, 20몰씩 부가시켜 제조한 POE 알킬 에테르류와 각각 반응시켜 15종의 올리고머 음이온성 계면활성제를 좋은 수율로 합성하였고, 이들 최종 합성화합물에 대하여 IR, NMR, 원서분석 등 기기분석을 행하여 분리확인하였다.

• Archives of Pharmacal Research
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• 제29권1호
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• pp.50-58
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• 2006

Translationally controlled tumor protein (TCTP), also known as histamine releasing factor (HRF), is found abundantly in different eukaryotic cell types. The sequence homology of TCTP between different species is very high, belonging to the MSS4/DSS4 superfamily of proteins. TCTP is involved in both cell growth and human late allergy reaction, as well as having a calcium binding property; however, its primary biological functions remain to be clearly elucidated. In regard to many possible functions, the TCTP of Plasmodium falciparum (Pf) is known to bind with an antimalarial agent, artemisinin, which is activated by heme. It is assumed that the endoperoxide-bridge of artemisinin is opened up by heme to form a free radical, which then eventually alkylates, probably to the Cys14 of PfTCTP. Study of the docking of artemisinin with heme, and subsequently with PfTCTP, was carried out to verify the above hypothesis on the basis of structural interactions. The three dimensional (3D) structure of PfTCTP was built by homology modeling, using the NMR structure of the TCTP of Schizosaccharomyces pombe as a template. The quality of the model was examined based on its secondary structure and biological function, as well as with the use of structure evaluating programs. The interactions between artemisinin, heme and PfTCTP were then studied using the docking program, FlexiDock. The center of the peroxide bond of artemisinin and the Fe of heme were docked within a short distance of $2.6{\AA}$, implying the strong possibility of an interaction between the two molecules, as proposed. When the activated form of artemisinin was docked on the PfTCTP, the C4-radical of the drug faced towards the sulfur of Cys14 within a distance of $2.48{\AA}$, again suggesting the possibility of alkylation having occurred. These results confirm the proposed mechanism of the antimalarial effect of artemisinin, which will provide a reliable method for establishing the mechanism of its biological activity using a molecular modeling study.

• Natural Product Sciences
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• 제27권4호
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• pp.245-250
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• 2021

The methylglyoxal (MGO) trapping constituents from Malus baccata L. were investigated using incubation of MGO and crude extract under physiological conditions followed by HPLC analysis. The peak areas of MGO trapping compounds decreased, and their chemical structures were identified by HPLC-ESI/MS. Sieboldin was identified as a major active molecule representing MGO-trapping activity of the crude extract. After reaction of sieboldin and MGO, remaining MGO was calculated by microplate assay method using imine (Schiff base) formation of 2,4-dinitrophenylhydrazine (DNPH) and aldehyde group. After 4 h incubation, sieboldin trapped over 43.8% MGO at a concentration of 0.33 mM and showed MGO scavenging activity with an RC₅₀ value of 0.88 mM for the incubation of 30 min under physiological conditions. It was also confirmed that sieboldin inhibited the production of advanced glycation end products (AGE) produced by bovine serum albumins (BSA)/MGO. Additionally, MGO trapping mechanism of sieboldin was more specifically identified by ¹H-, ¹³C-, 2D NMR and, confirm to be attached to the position of C-3' (or 5').

• Macromolecular Research
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• 제15권5호
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• pp.430-436
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• 2007

The dinuclear half-sandwich CGCs (constrained geometry catalyst) with a polymethylene bridge, $[Ti({\eta}^5 : {\eta}^1-indenyl)SiMe_2NCMe_3]_2(CH_2)_n]$[n = 6 (1) and 12 (2)], have been employed in the copolymerization of ethylene and norbornene (NBE). To compare the mononuclear metallocene catalysts; $Ti({\eta}^5 : {\eta}^1-2-hexylindenyl)SiMe_2NCMe_3$ (3), $(Cp^* SiMe_2NCMe_3)$Ti (Dow CGC) (4) and ansa-$Et(Ind)_2ZrCI_2$ (5), were also studied for the copolymerization of ethylene and NBE. It was found that the activity increased in the order: 1 < 2 < 3 < 5 < 4, indicating that the presence of the bridge between two the CGC units contributed to depressing the polymerization activity of the CGCs. This result strongly suggests that the implication of steric disturbance due to the presence of the bridge may playa significant role in slowing the activity. Dinuclear CGCs have been found to be very efficient for the incorporation of NBE onto the polyethylene backbone. The NBE contents in the copolymers formed ranged from 10 to 42%, depending on the polymerization conditions. Strong chemical shifts were observed at ${\delta}$42.0 and 47.8 of the isotactic alternating NBE sequences, NENEN, in the copolymers with high NBE contents. In addition, a resonance at 47.1 ppm for the sequences of the isolated NBE, EENEE, was observed in the $^{13}C-NMR$ spectra of the copolymers with low NBE contents. The absence of signals for isotactic dyad at 48.1 and 49.1 ppm illustrated there were no isotactic or microblock (NBE-NBE) sequences in the copolymers. This result indicated that the dinuclear CGCs were effective for making randomly distributed ethylene-NBE copolymers.

• 폴리머
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• 제31권5호
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• pp.454-459
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• 2007

본 연구에서는 folic acid(FA)가 복합화된 저분자량 수용성 키토산(LMWSC) 나노입자(water soluble chitosan-folic acid nanoparticle, WSCFA)를 제조하고, 또한 DNA와 나노복합체 합성 및 특성을 분석함으로써 in vitro에서 세포내 독성을 평가하였다. WSCFA 합성을 확인하기 위하여 분광학적 분석 방법을 사용하여 분석하였으며, WSCFA 나노입자는 110 nm 이하의 입자 크기인 구형의 형태를 가지고 있음을 알 수 있었다. In vitro 세포내 독성 실험에서, WSCFA-DNA 복합체는 세포내 독성을 전혀 나타내지 않음으로 높은 세포 생존율을 보여주었다. 전기영동 실험을 통해 WSCFA의 DNA 응축능력을 확인하였고, in vitro에서의 전이효율은 형광 광도계에 의해 평가하였다.

• Applied Biological Chemistry
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• 제51권3호
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• pp.223-227
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• 2008

사자발쑥의 지상부를 80% MeOH용액으로 추출하고, 얻어진 추출물을 EtOAc, H-BuOH 및 $H_2O$로 용매 분획 하였다. 이 중 EtOAc 분획으로부터 silica gel과 octadecyl silica gel(ODS), Sephadex LH-20 column chromatography로 정제하여 4종의 triterpenoid를 분리하였다. 각 화합물의 화학구조는 NMR, MS 및 IR 등의 스펙트럼 데이터를 해석하여 wrightial(1), wrightial acetate(2), 27-norcycloart-20(21)-ene-25-al-3${\beta}$-ol acetate(3) 및 ursolic acid(4)로 동정하였다. 이 화합물들은 사자발쑥에서 처음으로 분리 보고 되었으며 특히, 화합물 3은 천연에서 처음으로 분리 보고 되었다. 또한 이번에 분리한 화합물에 대하여 항고지혈증 활성을 측정한 결과 화합물 1은 ACAT1과 ACAT2 효소에 대한 $IC_{50}$ 값이 33 ${\mu}g/ml$와 45 ${\mu}g/ml$로 나타났고, 화합물 2는 ACAT1 효소에 대하여 $IC_{50}$ 값이 12 ${\mu}g/ml$로 나타났다. 화합물 3은 ACATI 효소에 대하여 $IC_{50}$값이 16 ${\mu}g/ml$으로 나타났다.

• Journal of Ginseng Research
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• 제43권2호
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• pp.186-195
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• 2019

Background: Notoginseng stem-leaf (NGL) ginsenosides have not been well used. To improve their utilization, the biotransformation of NGL ginsenosides was studied using ginsenosidase type-I from Aspergillus niger g.848. Methods: NGL ginsenosides were reacted with a crude enzyme in the RAT-5D bioreactor, and the dynamic changes of multi-ginsenosides of NGL were recognized by HPLC. The reaction products were separated using a silica gel column and identified by HPLC and NMR. Results: All the NGL ginsenosides are protopanaxadiol-type ginsenosides; the main ginsenoside contents are 27.1% Rb3, 15.7% C-Mx1, 13.8% Rc, 11.1% Fc, 7.10% Fa, 6.44% C-Mc, 5.08% Rb2, and 4.31% Rb1. In the reaction of NGL ginsenosides with crude enzyme, the main reaction of Rb3 and C-Mx1 occurred through Rb3${\rightarrow}$C-Mx1${\rightarrow}$C-Mx; when reacted for 1 h, Rb3 decreased from 27.1% to 9.82 %, C-Mx1 increased from 15.5% to 32.3%, C-Mx was produced to 6.46%, finally into C-Mx and a small amount of C-K. When reacted for 1.5 h, all the Rb1, Rd, and Gyp17 were completely reacted, and the reaction intermediate F2 was produced to 8.25%, finally into C-K. The main reaction of Rc (13.8%) occurred through Rc${\rightarrow}$C-Mc1${\rightarrow}$C-Mc${\rightarrow}$C-K. The enzyme barely hydrolyzed the terminal xyloside on 3-O- or 20-O-sugar-moiety of the substrate; therefore, 9.43 g C-Mx, 6.85 g C-K, 4.50 g R7, and 4.71 g Fc (hardly separating from the substrate) were obtained from 50 g NGL ginsenosides by the crude enzyme reaction. Conclusion: Four monomer ginsenosides were successfully produced and separated from NGL ginsenosides by the enzyme reaction.

• 생명과학회지
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• 제30권4호
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• pp.359-369
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• 2020

많은 면역 소재 연구에서 RAW 264.7 세포를 이용한 결과는 많이 보고되어 있으나 T 세포 유래 TK-1 세포를 활용한 연구결과는 거의 보고되어 있지 않다. 또한 식물 유래 성분인 β-sitosterol의 효능 연구에 비하여 그 유사체인 daucosterol의 면역 활성 조절 기능에 관한 연구도 매우 부족하다. 본 연구에서는 산약, D. batatas, 에서 β-sitosterol과 daucosterol을 추출하여 분리하고 NMR 방법으로 동정하였다. 이후 분리된 phytosterols의 면역 증강 또는 억제 효능을 규명하기 위해 lipopolysaccharide로 염증반응이 유도된 RAW 264.7 세포와 TK-1 세포에 β-sitosterol과 daucosterol을 각각 농도별로 12시간 동안 처리한 후에 염증관련 유전자인 COX-2, TNF-α, IL-6, iNOS의 상대적인 발현양을 RT-PCR 방법으로 분석하였다. 대식세포주인 RAW 264.7에 β-sitosterol을 처리하였을 때, LPS만을 처리한 대조군의 발현 증가량과 비교하여 TNF-α와 iNOS의 상대적인 발현양이 3 fold 이상 증가하였다. TK-1 세포의 경우에서는 β-sitosterol의 처리 농도의존적으로 TNF-α의 발현양은 감소하고 iNOS의 발현양은 증가하였다. Daucosterol을 RAW 264.7 세포에 처리한 경우 COX-2, TNF-α, IL-6의 발현양이 0.7~1.2 fold 정도로 변화하였으며 iNOS의 경우는 특이하게 0.8~0.18 fold로 발현양이 농도의존적으로 감소하였다. TK-1 세포에 daucosterol을 처리한 경우에는, 놀랍게도 LPS만 처리된 경우와 비교하여 상대적으로 TNF-α, IL-6, iNOS의 발현량이 급격하게 감소하는 것을 확인하였다. 결과적으로, β-sitosterol의 처리는 RAW 264.7 세포에서 TNF-α, iNOS의 발현증가를 유도하여 면역 상승 효과에 관여하였다. TK-1 세포에서는, iNOS 발현 수준이 증가하였고, 반면에 TNF-α 발현수준은 감소하여, β-sitosterol의 면역 억제 활성을 보여주었다. Daucosterol은 RAW 264.7 세포의 iNOS 발현양을 억제하고 TK-1 세포에서 TNF-α, IL-6, iNOS의 발현을 크게 억제함으로써, 대식세포와 T 세포주에서 모두 면역 억제 효능을 보이는 것으로 판단된다.

• 한국의학물리학회지:의학물리
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• 제21권1호
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• pp.35-41
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• 2010

본 연구는 생체 외 $^1H$ 고분해능 매직앵글스핀닝($^1H$ High-Resolution Magic Angle Spinning; $^1H$ HR MAS) 기술을 이용하여 정상군 adult mice의 뇌에서의 부위별 뇌 신경화학 대사물질(brain neurochemical metabolites)을 정량적으로 분석하고, 이를 이용하여 정상군의 뇌 대사물질의 표준 data base를 정립하기 위함이다. 실험에 사용된 adult mice는 C57BL/6J 모델의 체중 25~28 g, 40주령 수컷 10마리를 사용하였으며, 연령과 성별을 일치시켰다. 또한 뇌의 전두엽(frontal cortex), 측두엽(temporal cortex), 해마(hippocampus), 시상(thalamus) 총 4개의 부위를 채취하여 생체 외 $^1H$ 고분해능 매직앵글 스핀닝 실험을 진행 하였다. 생체 조직의 뇌 대사물질의 절대농도를 획득하기 위하여 대표적인 대사물질(Ace, NAA, NAAG, tCr, Cr, tCho, Cho, mIns, GPC+PC, Lac, GABA, Glu, Gln, tau, Ala)을 각 피크의 면적과 대사물질의 프로톤 개수를 계산하였다. 결과적으로 정상 군에서의 mice 뇌의 신경화학 대사물질들을 Acet, NAA, NAAG, Cho, mIns가 부위별로 절대농도차의 유의성을 나타내었으며, 이 외의 대사물질에서는 유의성이 없는 것으로 나타났다. 본 연구 결과를 토대로 $^1H$ HR-MAS을 이용한 생체조직 실험은 뇌조직 내 대사물질의 절대농도를 측정하고 기본적인 지표를 확보하는데 매우 정확하고 정량적인 방법이 될 수 있을 것으로 사료되며, 더 나아가 mice를 이용한 인간질병 모델의 실험동물에서의 뇌 신경화학 대사물질의 표준 자료화 하는데 도움이 될 수 있을 것으로 판단된다.