• Journal of Microbiology and Biotechnology
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• 제16권4호
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• pp.637-638
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• 2006

Bioassay-guided fractionation of an organic extract of the culture broth from an unidentified marine-derived fungus led to the isolation of a new metabolite, N-[2-(4-hydroxyphenyl) acetyl]formamide (1), along with four known polyketides, 4-hydroxyphenyl acetamide (2), 4-hydroxyphenyl acetic acid (3), 3,4-dihydroxyphenyl acetic acid (4), and N-[2-(4-hydroxyphenyl)ethenyl]formamide (5). The structures of 1-5 were elucidated by spectral data analyses. Among them, compounds 1, 4, and 5 exhibited significant radical scavenging activity against 1, 1-diphenyl-2-picrylhydrazyl (DPPH) with $IC_{50}$ values of 8.4, 11.9, and $0.2{\mu}M$, respectively.

• Journal of Applied Biological Chemistry
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• 제43권4호
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• pp.264-268
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• 2000

High activity of acidic ethylacetate extract from the culture supernatant of ginseng growth-promoting bacterium Pseudomonas fluorescens KGPP 207 and its fractions were demonstrated through wheat coleoptile bioassay. The following auxins and auxin-like compounds were identified in these fractions by combined gas chromatography-mass spectrometry: indole-3-acetic acid, indole-3-acetic acid methyl and ethyl ester, indole-3-butyric acid, indole-3-lactic acid and its methyl ester, indole-3-propionic acid, indole-3-pyruvic acid, p-hydroxyphenyl acetic acid, p-hydroxyphenyl acetic acid methyl and ethyl ester, phenyl acetic acid and its methyl ester. The bacterium KGPP 207 belongs to the strain of P. fluorescens which produces plant growth regulators and its beneficial effect on the ginseng growth may be due to the formation of the identified compounds.

• Advances in nano research
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• 제14권2호
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• pp.201-210
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• 2023

A ZnO/poly (amide-imide) hybrid nanocomposite film with different weight percentages of Zinc oxide (ZnO) nanoparticles is synthesized and characterized in this paper. A two-step reaction successfully synthesized a new kind of heteroaromatic diamine with bulky pendant groups. In order to produce 3, 5-dinitro-3, 3-bis (4-(4-Nitrophenoxy) phenyl) -2- benzofuran-1-one, 3, 3'-bis (4-hydroxyphenyl) benzofuran-1-one and 3'-bis (4-hydroxyphenyl) benzofuran-1-one were combined with 3'-bis (3-hydroxyphenyl) benzofuran-1-one. The obtained dinitro was then reduced by zinc dust and hydrochloric acid. The reaction of 4, 4^* carbonyl diphthalic anhydride with amino acid L-alanine in acetic acid leads to the production of very high yields of chiral diacid monomer. As a result of the direct polymerization of these monomers, new optically active polymers were formed (amide-imide). In order to synthesize poly (amide-imide)/ZnO nanocomposites with different weight percentages (2, 4, 6, 8, and 10%), PAI and ZnO nanoparticles were combined using ultrasonication SEM, Fourier transform infrared spectroscopy, X-ray diffraction and thermal gravimetry were used to characterize the PAI films.

• Current Research on Agriculture and Life Sciences
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• 제31권3호
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• pp.165-169
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• 2013

Rutin is one of the major flavonoids found in buckwheat (Fagopyrum esculentum Moench). While rutin is already known to exhibit anti-oxidative, anti-inflammatory, and anti-carcinogenic activities. However, the health beneficial function of rutin metabolites is not well understood. In DPPH radical scavenging assays, the present study found that 3,4-dihydroxyphenyl acetic acid had the highest total anti-oxidant activity, followed by 3,4-dihydroxyphenylacetic acid, rutin, homovanillic acid, and 3-hydroxyphenyl acetic acid. Further, 3,4-dihydroxyphenylacetic acid strongly reduced LPS-induced IL-6 production in RAW 264.7 cells, compared with other metabolites. Therefore, these results suggest that rutin metabolites have potential to be utilized as food ingredients with anti-oxidant and anti-inflammatory activities.

• 대한화학회지
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• 제56권3호
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• pp.348-356
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• 2012

In an attempt to find a new class of bisazo disperse dyes with better dyeing properties, a series of novel bisazo dyestuffs based on 4-arylhydrazono-3-(2'-hydroxyphenyl)-1-phenyl-2-pyrazolin-5-ones $\mathbf{3a-f}$ were prepared by diazocoupling of p-nitrophenyl diazonium chloride with 4-arylhydrazono-3-(2'-hydroxyphenyl)-1-phenyl-2-pyrazolin-5-ones $\mathbf{2a-f}$. Compounds $\mathbf{3a-f}$ were subsequently reacted with acetic anhydride in the presence of p-toluenesulfonic acid afford the corresponding O-acetyl derivatives $\mathbf{4a-f}$. The latter products as well as spectral data indicated that compounds $\mathbf{3a-f}$ exist predominantly in the azo-hydrazone tautomeric form (H) as the ZE-configuration. Additionally, two series of the synthesized dyes $\mathbf{3a-f}$ and $\mathbf{4a-f}$ were applied as disperse dyes for dyeing polyester fabrics and their fastness properties were evaluated. Also the position of color in CIELAB coordinates ($L^*$, $a^*$, $b^*$, $H^*$, $C^*$*) was assessed.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.529-529
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• 2012

Dispersion of carbon nanotubes in biocompatible media are of particular interest for diverse biomedical and nanomedicine applications. Various biomolecules and biopolymers such as DNA, proteins, poly L-lysine, starch, gelatin, steroid biosurfactants, and chitosan have shown capability for the effective dispersion of carbon nanotubes in water. Chitosan has demonstrated capacity for effective dispersion of single-walled carbon nanotubes (SWCNTs) in acidic medium and it also showed tendency to preferentially disperse smaller diameter nanotubes. Chemical functionalizations of chitosan enable its solubility in neutral pH water by reducing the intra and inter molecular hydrogen bonding. Herein, we present a neutral pH water soluble chitosan derivative, chitosan-hydroxyphenyl acetamide (CHPA), obtained by functionalizing the amino groups of chitosan with 4-hydroxyphenyl acetic acid, as an efficient biocompatible dispersant for debundling and solubilization of SWNTs in neutral aqueous solutions. Various process conditions for individual dispersion of SWCNTs are analyzed based on optical absorption and Raman spectroscopy.

• Applied Biological Chemistry
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• 제40권6호
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• pp.501-507
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• 1997

파라과이 원산의 국화과 식물 Stevia rebaudiana Bertoni는 steviol (ent-13-hydroxy kaur-16-en-19-oic acid)을 기본 골격으로 하는 stevia 감미료를 건물 중량의 5-10%를 생합성하여 축적을 한다. 감미성분은 Gibberellin 생합성의 전구체로 알려진 ent-kaurenoic acid (ent-kaur-16-en-19-oic acid; ent-KA)의 7번과 13번의 어느 탄소에 hydroxylation을 시키느냐에 따라 gibberellin 대사와 steviol 대사로 나뉘어진다. ent-KA 13-hydroxylase를 stevia 엽록체의 stroma에 존재하는 것을 확인했다. Stroma 분획 단백질 $100\;{\mu}g$으로 효소 반응의 cofactor 요구성을 조사해 본 결과, 반응 혼합액에 NADPH를 첨가하지 않았을 때는 85%의 효소활성의 감소를 보였고, NADPH 대신 NADH를 첨가해도 34%의 감소를 보였다. anaerobic 조건에서는 2.1%의 활성을 뛰었다. 이 결과로 ent-KA 13-hydroxylase는 NADPH와 $O_2$ 요구성임을 밝혔다. FAD, FMN, riboflavin을 첨가함으로써 FAD는 1.5배, riboflavin은 1.7배의 효소활성 증가 효과가 나타났다. 효소의 기질 특이성을 조사한 결과, t-cinnamic acid, 4-hydroxyphenyl acetic acid, choline과 resorcinol에는 전혀 활성이 검출되지 않았으며, $[^(14)C]-methyl-KA$를 ent-KA 대신에 기질로 사용했을 때는 16.7% 의 활성이 검출되어 ent-KA 13-hydroxylase는 기질특이성이 높은것으로 확인되었다.

• 한국식품저장유통학회지
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• 제22권4호
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• pp.607-612
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• 2015

본 연구는 rutin 및 rutin 대사체인 DHPAA, HPAA, DHT, HVA가 버섯 유래 tyrosinase 활성과 마우스 피부표피 세포주인 JB6 P+ 세포의 증식에 미치는 영향에 대해 살펴보았다. HVA가 버섯유래 티로시나제 저해활성이 가장 우수한 것으로 관찰되었으며, DHPAA, HPAA, rutin, DHT 순서로 저해효능을 나타내었다. DHT를 제외한 rutin 및 rutin 대사체들 모두 $100{\mu}M$ 까지 세포 독성이 관찰되지 않은 것으로 관찰되었으며, DHT는 50 또는 $100{\mu}M$에서 세포증식을 저해하였으나 그 이하의 농도에서는 세포독성을 유도하지 않았다. 따라서 본 연구결과, rutin 대사체 모두 세포 독성이 없는 수준에서 버섯 유래 티로시나제 활성을 효과적으로 억제하였으므로, 앞으로 미백제제로 활용될 수 있을 것으로 기대된다.

• Macromolecular Research
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• 제17권7호
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• pp.522-527
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• 2009

A photocrosslinkable polyphosphazene was used for molecular imprinting. We synthesized polyphosphazene (3) having urea groups for complexation with N-carbobenzyloxyglycin (Z-Gly-OH, template) and chalcone groups for cross-linking reaction. As substituents, 4-hydroxycha1cone (1) and N-(4-hydroxyphenyl)-N'-ethylurea (2) were prepared. Choloro groups of poly(dichlorophosphazene) were replaced by the sequential treatment with sodium salts of compounds 1 and 2, and trifluoroethanol. The template molecule was complexed with the urea groups on the polymer chains via hydrogen bonding. A thin polymer film was prepared by casting a solution of the complex of polymer 3 and the template in dimethylformamide on a quartz cell and irradiated with 365 nm UV light to yield a cross-linked film with a thickness of about $16{\mu}m$. The template molecules in the film were removed by Soxhlet extraction with methanol/acetic acid. The control polymer film was prepared in the same manner for the preparation of the imprinted polymer film, except that the template and triethylamine were omitted. In the rebinding test, the imprinted film exhibited much higher recognition ability for the template than the control polymer. We also investigated the specific recognition ability of the imprinted polymer for the template and its structural analogues. The rebinding tests were conducted using Z-Glu-OH, Z-Asp($O^tBu$)-OH, and Z-Glu-OMe. The imprinted film showed higher specific recognition ability for the template and the lowest response for Z-Asp($O^tBu$)-OH.

• Biomolecules & Therapeutics
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• 제24권3호
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• pp.298-304
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• 2016

Dianthus superbus (D. superbus) is a traditional crude drug used for the treatment of urethritis, carbuncles and carcinomas. The objective of this study was to confirm the cognitive enhancing effect of D. superbus in memory impairment induced mice and to elucidate the possible potential mechanism. Effect of D. superbus on scopolamine induced memory impairment on mice was evaluated using the Morris water maze and passive avoidance tests. We also investigated acetylcholinesterase (AChE) activity and brain-derived neurotropic factor (BDNF) expression in scopolamine-induced mice. HPLC-DAD analysis was performed to identify active compounds in D. superbus. The results revealed that D. superbus attenuated the learning and memory impairment induced by scopolamine. D. superbus also inhibited AChE levels in the hippocampi of the scopolamine-injected mice. Moreover, D. superbus increased BDNF expression in the hippocampus. Eight compounds were identified using HPLC-DAD analysis. The content of 4-hydroxyphenyl acetic acid was higher than contents of other compounds. These results indicated that D. superbus improved memory functioning accompanied by inhibition of AChE and upregulation of BDNF, suggesting that D. superbus may be a useful therapeutic agent for the prevention or treatment of Alzheimer's disease.