• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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• pp.89-94
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• 1998

Marine sponges are recognized as a plentiful source of diverse biologically active secondary metabolites. Recently, we have initiated a research to discover antitumor constituents from the marine sponges collected from Korean Waters. Marine sponges collected from the South Sea of Korea were screened for several biological activities including such as brine shrimp lethality and cytotoxicity. Significant brine shrimp lethality was detected in the crude extract of a two-sponge association of Poecillastra sp. and Jaspis sp. A cross-section of this sample showed two layers of morphologically distinct sponges. The thin and dirty yellow outer layer was identified as Poecillastra sp. (Pachastrellidae), the surface of which was very rough. The light-grey inner layer was identified as Jaspis sp. (Jaspidae), the surface of which was smooth. This two-sponge association appears to be consistent as these sponges were always found in associated form regardless of collection site or collection period. Investigation of the bioactive constituents monitored by brine shrimp lethality assay led to the isolation of pectenotoxin II (PTX2) and psammaplin A as causative compounds for the brine shrimp lethality. $^1$H- and $\^$13/C-nmr signals of PTX2 was fully assigned utilizing TOCSY, HETCOR, Long-range HETCOR, and Homonuclear J-resolved 2D experiments. PTX2 displayed very potent and selective cytotoxicities in the 60 cell line panel antitumor assay at the NCI. PTX2 has progressed to acute toxicity determination and in vivo antitumor assay at the NCI (Table 1). However, significant in vitro antitumor activity of PTX2 can not be affirmed in the in vivo assay.

• Journal of Microbiology and Biotechnology
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• 제20권7호
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• pp.1061-1068
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• 2010

The biological synthesis of nanoparticles has gained considerable attention in view of their excellent biocompatibility and low toxicity. We isolated and purified rhamnolipids from Pseudomonas aeruginosa strain BS-161R, and these purified rhamnolipids were used to synthesize silver nanoparticles. The purified rhamnolipids were further characterized and the structure was elucidated based on one- and two-dimensional $^1H$ and $^{13}C$ NMR, FT-IR, and HR-MS spectral data. Purified rhamnolipids in a pseudoternary system of n-heptane and water system along with n-butanol as a cosurfactant were added to the aqueous solutions of silver nitrate and sodium borohydride to form reverse micelles. When these micelles were mixed, they resulted in the rapid formation of silver nanoparticles. The synthesized nanoparticles were characterized by UV-Visible spectroscopy, transmission electron microscopy, and energy dispersive X-ray spectroscopy (EDS). The nanoparticles formed had a sharp adsorption peak at 410 nm, which is characteristic of surface plasmon resonance of the silver nanoparticles. The nanoparticles were monodispersed, with an average particle size of 15.1 nm (${\sigma}={\pm}5.82$ nm), and spherical in shape. The EDS analysis revealed the presence of elemental silver signal in the synthesized nanoparticles. The formed silver nanoparticles exhibited good antibiotic activity against both Grampositive and Gram-negative pathogens and Candida albicans, suggesting their broad-spectrum antimicrobial activity.

• Archives of Pharmacal Research
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• 제29권11호
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• pp.937-941
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• 2006

Ixeris dentata forma albiflora was extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and $H_{2}O$. Eight sesquiterpenes were isolated through repeated silica gel and octadecyl silica gel ($C_{18},\;ODS$) column chromatography of the EtOAc and n-BuOH fractions. Physicochemical analysis using NMR, MS and IR revealed the chemical structures of the sesquiterpenes, which were zaluzanin (1), 9a-hydroxyguaian-4(15), 10(14), 11 (13)-triene-6, 12-olide(2), $3{\beta}-O-{\beta}-D-glucopyranosyl-8{\beta}-hydroxyguaian$-4(15), 10(14)-diene-6, 12-olide (3), $3-O-{\beta}-D-glucopyranosyl-8{\beta}-hydroxyguauan$-10(14)-ene-6, 12-olide (4), ixerin M (5), glucozaluzanin C (6), crepiside I (7), and ixerin D (8). This is the first time that these sesquiterpene lactones have been isolated from this plant. Compounds 1, 2 and 7 revealed relatively high cytotoxicities on human colon carcinoma cell and lung adeno-carcinoma cell, while compounds 5 and 7 showed acyl-CoA: cholesterol acyltransferase (ACAT) inhibitory activity.

• Macromolecular Research
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• 제8권1호
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• pp.44-52
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• 2000

Styrenic macromonomers with/without a silyloxy-functional group were synthesizedvia chain-end functionalization using 4-vinylbenzyl chloride as a terminating agent insec-butyllithium-initiated polymerization of styrene. The yields were 92 mol% for the silyloxy group and 88 mol% for the styrenic unit. Crystalline polystyrene-g-amorphous polystyrenes were synthesized by (η$^{5}$ -indenyl)-trichlorotitanium ((Ind)TiCl$_3$)-catalyzed copolymerizations of the macromonomers with styrene in the presence of methyl-aluminoxane (MAO) in toluene at 4$0^{\circ}C$. The macromonomer having $\alpha$, $\alpha$'-bis (4-[tert-butyldimethylsilyl-oxy]phenyl) group was also utilized for the preparation of a precursor of hydroxyl-functionalized syndio-tactic polystyrene. The obtained polymers were characterized by a combination of$^1$H, $^{13}$ C NMR spectroscopic, size exclusion chromatographic, and differential scanning calorimetric analysis. The (Ind)TiCl$_3$-catalyzed copolymerization of styrene with the macromonomer carrying the silyloxy functional group was found to be an efficient method to modify syndiotactic polystyrene without a great loss of physica] property by controlling the feud ratio of the macromonomer.

• BMB Reports
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• 제44권5호
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• pp.335-340
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• 2011

In this study, we attempted to isolate novel mast cell-stimulating molecules from Staphylococcus aureus. Water-soluble extract of S. aureus cell lysate strongly induced human interleukin-8 in human mast cell line-1 and mouse interleukin-6 in mouse bone marrow-derived mast cells. The active molecule was purified to homogeneity through a $C_{18}$ reverse phase HPLC column. By determination of its structure by MALDITOF and $^1H$- and $^{13}C$-NMR, adenosine was revealed to be responsible for the observed cytokine induction activities. Further studies using 8-sulfophenyl theophylline, a selective adenosine receptor blocker, verified that purified adenosine can induce interleukin-8 production via adenosine receptors on mast cells. Moreover, adenosine was purified from S. aureus-engulfed RAW264.7 cells, a murine macrophage cell line, used to induce phagocytosis of S. aureus. These results show a novel view of the source of exogenous adenosine in vivo and provide a mechanistic link between inflammatory disease and bacterial infection.

• 한국식품영양과학회지
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• 제46권6호
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• pp.759-764
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• 2017

당뇨합병증에 효과적인 천연물 유래의 신소재를 개발하기 위하여 본 연구를 수행하여 단풍취 70% 에탄올 추출물의 EtOAc 가용부로부터 최종당화산물 생성 억제능($IC_{50}=5.5{\pm}1.1{\mu}g/mL$)을 확인하였다. 활성을 나타내는 성분의 동정을 위하여 $C_{18}$겔 등을 활용한 칼럼크로마토그래피를 수행하여 4종의 dicaffeoylquinic acid 유도체 화합물을 분리하였고, 각 화합물의 화학구조는 NMR 스펙트럼 데이터 해석 및 표품과의 HPLC 직접 비교를 통하여 methyl 3,5-di-O-caffeoyl-epi-quinate(1), 3,5-di-O-caffeoyl-epi-quinic acid(2), 4,5-di-O-caffeoyl-quinic acid(3) 및 methyl 4,5-di-O-caffeoyl-quinate(4)로 동정하였다. 이들 화합물에 대해 최종당화산물 생성 억제능을 평가한 결과 4,5-di-O-caffeoyl-quinic acid(3)가 가장 강한 $0.4{\pm}0.1{\mu}M$의 $IC_{50}$ 값을 나타내었으며, 3,5-di-O-caffeoyl-epi-quinic acid(2)가 $0.6{\pm}0.1{\mu}M$의 $IC_{50}$ 값을 나타내었다. 또한, 이들 물질에 대해 $ABTS^+$ 소거 활성을 평가하여 4,5-di-O-caffeoyl-quinic acid(3)가 가장 강한 라디칼 소거 활성인 $14.6{\pm}0.4{\mu}M$의 $IC_{50}$ 값을 나타내었으며, 구조 이성질체인 3,5-di-O-caffeoyl-epi-quinic acid(2)가 $18.8{\pm}0.4{\mu}M$의 $IC_{50}$ 값을 확인하였다. 단풍취에서 분리한 화합물의 활성은 caffeic acid의 결합방식 및 methyl화 여부에 따른 화합물의 구조에 따라 다름이 시사되었다. 향후 우수한 활성을 나타낸 이들 화합물의 in vivo 실험을 통한 활성기작의 검증이 필요하다고 생각된다. 또한, 추가적인 연구를 통하여 식의약 소재로 활용이 가능한 새로운 천연신소재 발굴을 위한 기초자료제공 및 당뇨합병증에 효과적인 천연 물질의 상업화를 위한 귀중한 자료로 활용할 수 있으리라 판단된다.

• 생명과학회지
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• 제24권3호
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• pp.242-251
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• 2014

국내에서 자생하는 P. thunbergiana 잎의 메탄올 추출물로부터 사람의 간암세포주, SK-HEP-1에 apoptosis를 유도하는 광과민성물질을 찾기 위해 연구를 시작하였다. Apoptosis를 유도하는 광과민성물질을 순수분리하기 위해 column chromatography법과 TLC법을 이용하였으며, 순수분리한 물질의 구조동정을 위하여 1D-NMR과 2D-NMR 및 FAB-MS분석을 실시하였다. P. thunbergiana 잎으로부터 크로마토그래피법을 이용해 순수분리한 M4-3 화합물의 흡광도를 측정한 결과 410 nm에서 최대 흡수를 보였고, 668, 502, 533, 607 nm에서 흡수 peak가 나타나는 녹색의 물질로 chlorophyll a, b와는 다른 물질이었다. FAB-MS 분석결과와 NMR 분석결과, 분자량 622의 132-hydroxy pheophorbide a methyl ester($C_{36}H_{28}N_2O_6$) 화합물로 porphyrin 환으로부터 Mg이온이 떨어져나간 pheophorbide a유도체화합물로 동정되었다. M4-3화합물을 SK-HEP-1세포에 대한 세포독성을 조사한 결과, 0.04 ${\mu}M$ 농도로 처리한 곳에서는 40% 세포증식 억제효과가 나타났고, 0.08 ${\mu}M$ 농도로 처리한 곳에서는 80% 세포증식 억제효과가 나타나 농도의존적이었다. 그리고 M4-3화합물을 동일한 농도로 처리하고, 광의 조사 유무에 따른 활성차이를 조사한 결과, 광을 조사한 곳에서만 세포독성이 나타났기 때문에 M4-3화합물은 광과민성물질이라는 것을 알 수 있었다. M4-3화합물을 처리하고 세포의 형태학적 변화를 관찰한 결과, 핵이 응축되었고, 소낭이 형성되었으며, DNA 단편화가 일어나는 등 apoptosis의 대표적인 현상들이 일어났기 때문에 M4-3화합물의 세포사멸은 광역학활성에 의한 apoptosis유도로 확인하였다.

• 생명과학회지
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• 제26권5호
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• pp.545-554
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• 2016

히알루론산(HA, Hyaluronic acid)은 β-1, 3-N-acetyl glucosamine과 β-1, 4-glucuronic acid가 반복된 선형 폴리머 고분자로서 생물학적 활성 및 생체친화성 특성 때문에 의약 및 약학분야에서 중요한 분자로 여겨지고 있다. 본 연구는 HA을 S. dysgalactiae으로 얻고, 화학적 방법을 통해 황화된 히알루론산(S-HA, Sulfated hyaluronic acid) 유도체를 합성하여 그 구조와 항염증 활성을 비교하였다. HA의 생산은 S. dysgalactiae를 5 l 생물반응기를 이용하여 대량 배양하여 수용성 히알루론산(HA-WS, water soluble hyaluronic acid)과 비수용성 히알루론산(HA-WI, water insoluble hyaluronic acid)을 분리 정제하였다. 특히 HA-WI를 황화시켜 황화된 히알루론산(S-HA) 유도체를 합성하였으며, 그 수율은 90%로 나타났다. 합성된 S-HA의 구조를 FT-IR 및 ¹H/¹³C-NMR를 통해 S. dysgalactiae로부터 생산된 표준 HA, HA-WS 및 HA-WI와 비교 분석한 결과, 황으로 치환된 양상을 확인하였다. 또한, S-HA 의 항염증 활성을 RAW 264.7 대식세포를 통해 확인한 결과, S-HA는 천연 형태의 HA (HA, HA-WS)보다 nitric oxide (NO)와 COX-2 및 PGE₂ 유전자 발현이 유의하게 낮게 발현되었다. 염증 매개 cytokine인 TNF-α (<80 pg/ml) 및 IL-6 (<100 pg/ml)의 생성도 S-HA가 천연 HA보다 낮은 수준으로 정량되었다. 이 같은 결과에서 황화된 S-HA은 천연 히알루론산보다 용해성이 우수하고 염증관련 사이토카인의 생성 억제를 통해 항염증 효과를 나타내므로 염증치료제, 성형 및 생체 적용 약물전달 소재로 그 활용이 기대된다.

• 대한화장품학회지
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• 제32권4호
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• pp.227-231
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• 2006

주름생성의 주요 원인은 자외선, 공기 오염, 담배 연기, 스트레스 등을 들 수 있다. 특히, 자외선은 피부에 다양한 형태로 영향을 주어 깊은 주름, 잔주름, 피부거침, 피부건조와 같은 현상을 발생시켜 피부노화를 유발시킨다. 이러한 주름 생성 해결 및 피부 노화 문제의 해결은 화장품에서 가장 활발하게 연구되는 분야 중 하나이다. 최근에 열대 식물인 노니로부터 추출한 유효성분이 주름 개선에서 가장 중요한 콜라겐 생합성을 촉진하는 효과를 확인하였으며, 특히 노니 추출물로부터 분리한 스코폴레틴(scopoletin)이 이러한 효과를 주는 활성 성분임을 확인하였다. 스코폴레틴은 인체 섬유아 세포를 이용한 콜라겐 합성 촉진 효과 시험에서 농도 의존적으로 콜라겐 합성을 촉진하는 활성을 보였다($0.2{\mu}g/mL-89.5%$ 콜라겐 생합성 촉진. 또한, 주름 개선 효과를 확인하기 위해 3% (v/v) 노니 추출물을 함유한 크림을 이용하여 12주 동안 임상연구를 수행하여, 안면의 주름 감소 정도를 측정하였으며 이 제품이 주름을 감소시켜주는 뛰어난 효과가 있다는 것을 확인하였다. 이러한 결과들은 노니 추출물이 주름 개선효과가 매우 높으며, 노화 방지 원료로서 이용 가능성이 매우 높다는 것을 보여주는 것이라 할 수 있다.

• Bulletin of the Korean Chemical Society
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• 제30권4호
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• pp.873-881
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• 2009

Bis(phenylethynyl)dimethylsilane is branched by the hydrosilation of the phenylethynyl group with dichloromethylsilane, and then the resulting chlorosilane is reacted with lithium phenylacetylide to give the $1^{st}$ generation. The same hydrosilation and alkynylation are repeated to obtain the $7^{th}$ generation. In addition peripheral Si-Cl moiety of the seven kind generation dendrimers are reacted with alcoholic moiety of 9-hydroxymethylanthracene and 2-(2-hydroxyphenyl)benzoxazole group in the presence of TMEDA. Then three kinds of carbosilane dendrimers are prepared from the $1^{st}$ to the $7^{th}$ generations, the $7^{th}$ generation of each dendrimer has 256 phenylethynyl, 256 9-anthracenylmethoxy, or 128 2-(2-phenoxy)benzoxazole groups. Each synthesized dendrimer is unequivocally characterized by $^1H\;and\;^{13}C\;NMR$, elemental analysis, MALDI-MS, GPC, and PL (photoluminescence). Characteristically PDI (Polydisperse Index) values of the dendrimers’ peak in GPC are in the range of $1.00{\sim}1.07$, which indicates that each generation of carbosilane is in unified distribution. PL spectra of phenylethynyl and 9- anthracenemethoxy group substituted dendrimers show no significant change with increasing the generation from the $1^{st}$ to the $7^{th}$. However, the PL spectra of 2-(2-phenoxy)benzoxazole group substituted dendrimers show a blue-shift trend with increasing the generation from the $1^{st}$ to the $7^{th}$.