• Title/Summary/Keyword: K4

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Flavonoids and Aromatic Compounds from the Rhizomes of Zingiber zerumbet

  • Jang Dae Sik;Han Ah-Reum;Park Gowooni;Jhon Gil-Ja;Seon Eun-Kyoung
    • Archives of Pharmacal Research
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    • v.27 no.4
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    • pp.386-389
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    • 2004
  • Repeated column chromatography of the CHCI_3-soluble fraction of Zingiber zerumbet led to the isolation and identification of two aromatic compounds, p-hydroxybenzaldehyde (1) and vanillin (2), and six kaempferol derivatives, kaempferol-3,4',7-O-trimethylether (3), kaempferol-3-O-methylether (4), kaempferol-3,4'-O-dimethylether (5), 4'-O-acetylafzel in (6), kaempferol-3-O-(4-O-acetyl-$\alpha$-L-rhamnopyranoside)], 2',4'-O-diacetylafzelin (7), kaempferol-3-O-(2,4-O-diacetyl-$\alpha$-L-rhamnopyranoside)], and 3',4'-O-diacetylafzelin (8), kaempferol-3-O-(3,4-O-diacetyl-$\alpha$-L-rhamnopyranoside)]. The structures of 1-8 were identifed by analysis of spectroscopic data as well as by comparison with published values. This is the first report on the isolation of compounds 1-3 from this plant.

Two Different Pathways (a Chlorocatechol and a Hydroquinone Pathway) for the 4-Chlorophenol Degradation in Two Isolated Bacterial Strains

  • Bae, Hee-Sung;Rhee, Sung-Keun;Cho, Young-Gyun;Hong, Jong-Ki;Lee, Sung-Taik
    • Journal of Microbiology and Biotechnology
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    • v.7 no.4
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    • pp.237-241
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    • 1997
  • Two isolated strains, Comamonas testosteroni CPW301 and Arthrobacter ureafaciens CPR706, were able to use 4-chlorophenol (4-CP) as a sole carbon and energy source. CPW301 was found to degrade 4-CP via a meta-cleavage pathway in which the chloro-substituent was eliminated even when 4-chlorocatechol was cleaved by the catechol 2, 3-dioxygenase. In contrast, CPR706 removed chloride from 4-CP prior to the ring-fission reaction, producing hydroquinone as a transient intermediate during 4-CP degradation. CPR706 exhibited much higher tolerance for 4-CP than CPW301, which was indicated by the maximum degradable concentration and degradation rate.

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A Pathway for 4-Chlorobenzoate Degradation by Pseudomonas sp. S-47

  • Seo, Dong-In;Chae, Jong-Chan;Kim, Ki-Pil;Kim, Young-Soo;Lee, Ki-Sung;Kim, Chi-Kyung
    • Journal of Microbiology and Biotechnology
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    • v.8 no.1
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    • pp.96-100
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    • 1998
  • Pseudomonas sp. S-47 degraded 4-chlorobenzoate (4CBA) to 4-chlorocatechol (4CC) that was subsequently ring-cleaved to form 5-chloro-2-hydroxymuconic semialdehyde. These intermediate compounds were identified by GC-mass spectrometry and UV-visible spectrophotometry. 5-chloro-2-hydroxymuconic acid converted from 5-chloro-2- hydroxymuconic semialdehyde (5C-2HMS) was dechlorinated to produce 2-hydroxypenta-2,4-dienoic acid (2HP-2,4DA) by the strain. These results indicate that Pseudomonas sp. S-47 degrades 4CBA to 2HP-2,4DA via a novel pathway including the meta-cleavage of 4CC and dechlorination of 5C-2HMS.

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Synthesis of the New Saccharin Derivatives Containing Imidazolidine-2,4,5-trione or 2-Thio-imidazolidine-4, 5-dione Group (Imidazolidine-2,4,5-trione 혹은 2-thio-imidazolidine-4,5-dione기를 포함하는 새로운 saccharin 유도체의 합성)

  • Jung, Dai-Il;Byun, Suk-In;Kim, Yun-Young;Kim, Young-Hwan;Lee, Do-Hun;Song, Hyun-Ae;Lee, Yong-Gyun;Park, Yu-Mi;Choi, Soon-Kyu;Han, Jung-Tae
    • Journal of Life Science
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    • v.14 no.2
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    • pp.351-355
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    • 2004
  • Saccharin derivatives were synthesized by means of 4 reaction steps involved the reaction of 1-methylurea (or 1-methylthiourea) and oxalyl chloride. 1-Alkyl(or phenyl)-3-(1,1,3-trioxo-1,3-dihydro-1$^{6}$ -benzo[d]isothiazol-2-ylmethyl)-imidazolidine-2,4,5-trione 5 and 1-alkyl(or phenyl)-2-thioxo- 3-(1,1,3-trioxo-1,3-dihydro-1$^{6}$ -benzo-[d]isothiazol-2-ylmethyl)-imidazolidine-4,5-dione 12 were obtained by means of 4 reaction steps involved the reaction of 1-methyl-urea(or 1-methylthiourea) and oxalyl chloride.

Effects of Paf1 complex components on H3K4 methylation in budding yeast (출아효모에서 Paf1 복합체의 구성원들이 H3의 네번째 라이신의 메틸화에 미치는 영향)

  • Oh, Jun-Soo;Lee, Jung-Shin
    • Korean Journal of Microbiology
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    • v.52 no.4
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    • pp.487-494
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    • 2016
  • In Saccharomyces cerevisiae, Paf1 complex consists of five proteins, and they are structurally and functionally well conserved in yeast, fruit fly, plants, and human. With binding to RNA polymerase II from transcription start site to termination site, Paf1 complex functions as a platform for recruiting many types of transcription factors to RNA polymerase II. Paf1 complex contributes to H2B ubiquitination and indirectly influences on H3K4 di- and tri-methylation by histone crosstalk. But the individual effects of five components in Paf1 complex on these two histone modifications including H2B ubiquitination and H3K4 methylation largely remained to be identified. In this study, we constructed the single-gene knockout mutants of each Paf1 complex component and observed H3K4 mono-, di-, and trimethylation as well as H2B ubiquitination in these mutants. Interestingly, in each ${\Delta}paf1$, ${\Delta}rtf1$, and ${\Delta}ctr9$ strain, we observed the dramatic defect in H3K4 monomethylation, which is independent of H2B ubiquitination, as well as H3K4 di- and trimethylation. However, the protein level of Set1, which is methyltransferase for H3K4, was not changed in these mutants. This suggests that Paf1 complex may directly influence on H3K4 methylation by directly regulating the activity of Set1 or the stability of Set1 complex in an H2B ubiquitination independent manner.

Faraday Rotation of the Hoya FR5 and FR4 Glasses at Cryogenic Temperature (저온에서 Hoya FR5 및 FR4 유리의 Faraday 회전)

  • 이현곤;원영희;이경수
    • Korean Journal of Optics and Photonics
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    • v.6 no.4
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    • pp.352-358
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    • 1995
  • Measurements of the Faraday rotation and magnetization of terbium-doped Hoya FR5 glass and cerium-doped Hoya FR4 glass have been made as a function of temperature T in the range 4.2 K -10 K and of magnetic field H of up to 80 kG at the $Ar^+$ laser wavelength of 514.5nm. The saturations of magnetization and Faraday rotation above H/T> $5kG.K^{-1}$ can be analyzed by the quantum theory of paramagnetism. Calculated parameters show that the large Verdet constant of $Ce^{3+}$ glass is due to the effective $4f\rightarrow5d$ electric dipole transition effect and that of $Tb^{3+}$ glass is due to the magnetization effect.effect.

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Radical Scavenging Hydroxyphenyl Ethanoic Acid Derivatives from a Marine-Derived Fungus

  • Li Xifeng;Kim Se-Kwon;Kang Jung-Sook;Choi Hong-Dae;Son Byeng-Wha
    • Journal of Microbiology and Biotechnology
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    • v.16 no.4
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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.

Antifungal Activity of 2-Hydroxy 4,4'6'Trimethoxy Chalcone

  • Mishra, P.K.;Sarma, B.K.;Singhai, P.K.;Singh, U.P.
    • Mycobiology
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    • v.35 no.2
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    • pp.72-75
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    • 2007
  • Antifungal activity of 2-hydroxy 4,4'6'trimethoxy chalcone individually was tested against spore germination of ten fungi of different genera. Efficacy of the chemical was also tested against conidial germination and other growth parameters of Erysiphe pisi on excised pea leaves. 2-Hydroxy 4,4'6'trimethoxy chalcone inhibited spore germination at all the concentrations. Maximum inhibition was observed at 2000 ppm where more than 78 per cent inhibition of spore germination was observed in Ustilago cynodontis, Alternaria brassicicola, A. solani and Aspergillus flavus. It also reduced conidial germination of E. pisi significantly, when applied as pre-inoculation treatment.

Analysis on Subjective Image Quality Assessments for 4K-UHD Video Viewing Environments (4K-UHD 비디오 시청환경 특성분석을 위한 주관적 화질평가 분석)

  • Park, In-Kyung;Ha, Kwang-Sung;Kim, Mun-Churl;Cho, Suk-Hee;Cho, Jin-Soo
    • Journal of Broadcast Engineering
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    • v.15 no.4
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    • pp.563-581
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    • 2010
  • In this paper, we perform subjective visual quality assessments on UHD video for UHD TV services and analyze the assessment results. Demands for video services have been increased with availabilities of DTV, Internet and personal media equipments. With this trend, the demands for high definition video have also been increasing. Currently, 2K-HD ($1920{\times}1080$) video have been widely consumed over DTV, DVD, digital camcoders, security cameras and other multimedia terminals in various types, and recently digital cinema contents of 4K-UHD($3840{\times}2160$) have been popularly produced and the cameras, beam projects, display panels that support for 4K-UHD video start to come out into multimedia markets. Also it is expected that 4K-UHD service will appear soon in broadcasting and telecommunications environments. Therefore, in this paper, subjective assessments of visual quality on resolutions, color formats, frame rates and compression rates have been carried to provide basis information for standardization of signal specification of UHD video and viewing environments for future UHDTV. As the analysis on the assessments, UHD video exhibits better subjective visual quality than HD by the evaluators. Also, the 4K-UHD test sequences in YUV444 shows better subjective visual quality than the 4K-UHD test sequences in YUV422 and YUV420, but there is little perceptual difference on 4K-UHD test sequences between YUV422 and YUV420 formats. For the comparison between different frame rates, 4K-UHD test sequences of 60fps gives better subjective visual quality than those of 30fps. For bit-depth comparison, HD test sequences in 10-bit depth were little differentiated from those in 8-bit depth in subject visual quality assessment. Lastly, the larger the PSNR values of the reconstructed 4K-UHD test sequences are, the higher the subjective visual quality is. Against the viewing distances, the differences among encoded 4K-UHD test sequences were less distinguished in longer distances from the display.