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Multicatalytic Alkaline Serine Pretense from the Psychrotrophic Bacillus amyloliquefaciens S94

  • Son, Eui-Sun;Kim, Jong-Il
    • Journal of Microbiology
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    • v.41 no.1
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    • pp.58-62
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    • 2003
  • An extracellular pretense of Bacillus amyloliquefaciens S94 was purified to apparent homogeneity. The enzyme activity was strongly inhibited by general inhibitor for serine protease, PMSF, suggesting that the enzyme is a serine pretense. The purified enzyme activity was inhibited by leucine peptidase inhibitor, bestatin, suggesting that the enzyme is a leucine endopeptidase. The maximum proteolytic activity against different protein substrates occurred at pH 10, 45$^{\circ}C$ (protein substrate) and pH 8, 45$^{\circ}C$ (synthetic substrate). The purified enzyme was specific in that it readily hydrolyBed substrates with Leu or Lys residues at P$_1$ site. The pretense had characteristics of a cold-adapted protein, which was more active for the hydrolysis of synthetic substrate in the range of 15$^{\circ}C$ to 45$^{\circ}C$, specially at low temperature.

Antibacterial Activities of Methylelaiophylin (Methylelaiophylin의 항균활성)

  • Lee, Dong-Sun;Lee, Sang-Han;WOO, Ju-Hyung;Lee, Jin-Man;Seu, Young-Bae;Hong, Soon-Duck
    • Journal of Life Science
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    • v.7 no.3
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    • pp.180-185
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    • 1997
  • Methylelaiophylin generated superoxide radicals in Bacillus subtilis and showed antibacterial activity against a broad range of gram positive bacteria. The inhibition of DNA synthesis was more sensitive than one of RNA synthesis. A recombination-deficient mutant strain of B. subtilis was 2-fold more sensitive than a wild strain, and this sensitivity was reduced in the presence of an antioxidant, dithiothreitol. Methylelaiophylin generated superoxide radicals in B. subtilis lysates, and this suggests that the antibacterial activity of methylelaiophylin is related to the generation of active oxygen species in the cells.

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Inhibitory Activity of Diacylglycerol Acyltransferase by Tanshinones from the Root of Salvia miltiorrhiza

  • Ko, Jeong-Suk;Ryu, Shi-Young;Kim, Young-Sup;Chung, Mi-Yeon;Kang, Jong-Seong;Rho, Mun-Chual;Lee, Hyun-Sun;Kim, Young-Kook
    • Archives of Pharmacal Research
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    • v.25 no.4
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    • pp.446-448
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    • 2002
  • The inhibitory activity of tanshinones from Salvia miltiorrhiza was tested on rat liver diacylglycerol acyltransferase (DGAT). Cryptotanshinone (1) and 15,16-dihydrotanshinone I (3) exhibited potent DGAT inhibitory activities dose-dependently with $IC_{50}$ values of $10.5 {\;}{\mu\textrm{g}}/ml{\;}and{\;}11.1{\;}{\mu\textrm{g}}/ml$. However, tanshinone IIA (2) and tanshinone I (4) showed very weak inhibition ($IC_{50}{\;}value:{\;}>{\;}250{\;}{\mu\textrm{g}}/ml$). A dihydrofuran moiety was seemed to be responsible for the stronger inhibitory activity

The Change of Paleoenvironment during the Late Holocene in the Neungsan-ri Alluvial Plain, Buyeo-gun, Chungnam-Province, Korea (충남 부여 능산리 충적평야의 홀로세 후기 고환경 변화)

  • Yoon, Soon-Ock;Kim, Yae-sun;Hwang, Sangill
    • Journal of The Geomorphological Association of Korea
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    • v.23 no.3
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    • pp.1-11
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    • 2016
  • This study estimated vegetation environment and agricultural activity during the late Holocene inferred from pollen analysis of peat on floodplain of Wangpo-cheon around Neungsan-ri, Buyeo-gun, South Korea. By result of pollen analysis of 28 horizons from Trench NS 1 and NS 4, vegetation environment during 2,300 to 1,700 yr BP was divided into Pollen Zone I (Quercus-Alnus), Pollen Zone II (Quercus-Alnus-Gramineae) and Pollen Zone III (Pinus-NAP-Gramineae). The pollen analysis suggests that agricultural activity in the Buyeo area was widely spread from the early time of the Pre-Iron Age to the late Samhan Age and buckwheat field seem to be built to substitute paddy field during the early time of the Pre-Iron Age.

Effect of Crystal Form on in Vivo Topical Anti-Inflammatory Activity of Corticosteroids

  • Sohn, Young-Taek;Kim, Sun-Young
    • Archives of Pharmacal Research
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    • v.25 no.4
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    • pp.556-559
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    • 2002
  • The aim of this study was to gain information on the effects of the crystal form of corticosteroids on the topical anti-inflammatory activity. Two different crystal forms, Form A and Form B, of the drugs of prednicarbate, hydrocortisone, betamethasone 17-valerate, prednisolone, and methyl prednisolone were prepared and their topical anti-inflammatory activities were measured using arachidonic acid induced ear edema assay in mice. Two crystal forms of the drugs showed differences in anti-inflammatory activity. Among the drugs examined, Form B of prednicarbate and betamethasone 17-valerate showed significantly more potent anti-inflammatory activities as compared to their Form A.

Olive flounder (Paralichthys olivaceus) leukocytes stimulated with poly (I:C) could kill Miamiensis avidus (Ciliophora: Scuticociliatia) only when ciliates were immobilized by antiserum

  • Kang, Yue Jai;Kim, Ki Hong
    • Journal of fish pathology
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    • v.31 no.2
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    • pp.109-113
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    • 2018
  • The purpose of the present study was to determine whether the scuticocidal activity of olive flounder (Paralichthys olivaceus) head-kidney leucocytes can be enhanced by stimulation with polyinosine-polycytosine [poly (I:C)]. The growth of Miamiensis avidus was not affected by exposure to unstimulated or poly (I:C)-stimulated leucocytes alone, heat-inactivated immune serum alone, or unstimulated leucocytes plus heat-inactivated immune serum. However, leucocytes stimulated with poly (I:C) showed clearly high scuticocidal activity against M. avidus in the presence of heat-inactivated immune serum. Furthermore, numerous poly (I:C)-stimulated leucocytes occupied the surface of scuticociliates in the presence of the heat-inactivated immune serum, which led to lysis of scuticociliates. These results suggest that both of the stimulation of leukocytes and the immobilization of scuticociliates are necessary to kill scuticociliates by leukocytes.

Cytotoxic Lactones from the Pericarps of Litsea japonica

  • Ngo, Quynh-Mai Thi;Cao, Thao Quyen;Woo, Mi Hee;Min, Byung Sun
    • Natural Product Sciences
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    • v.25 no.1
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    • pp.23-27
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    • 2019
  • From the pericarps of Litsea japonica (Thunb.) Jussieu, eighteen butanolide derivatives (1 - 18) were evaluated for their cytotoxic activity against HeLa, HL-60, and MCF-7 cells. Compounds 1-9 with 2-alkylidene-3-hydroxy-4-methylbutanolides structure exhibited cytotoxic activities against cancer-cell lines. Among them, compound 8 (litsenolide $D_2$) exhibited the most potent cytotoxicity against the tested cell lines, including HeLa, HL-60, and MCF-7, with $IC_{50}$ values of $17.6{\pm}1.3$, $4.2{\pm}0.2$, and $12.8{\pm}0.0{\mu}M$, respectively. Compound 8 induced apoptosis in a dose-dependent manner. Annexin V/Propidium Iodide (PI) double staining confirmed that 8 effectively induced apoptosis in MCF-7 cells. To the best of our knowledge, we have reported cytotoxic activity of butanolides from L. japonica against these cancer-cell lines for the first time.

The Pressure Effect on the Activity Coefficient of Sodium Chloride and Bromide Ions

  • Jee, Jong-Gi;Lee, Sun-Haing;Cha, Seong-Keuck
    • Bulletin of the Korean Chemical Society
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    • v.7 no.3
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    • pp.163-166
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    • 1986
  • A new paraffin salt bridge was developed for the concentration cell in high pressure system. The emf values of the concentration cells were measured to calculate the activity coefficients of the electrolytic ions depending upon the pressure of the system. The activity coefficients of sodium, chloride and bromide ions increase with the temperature of the cell and decreased, nearly half at 2500 bars, $20^{\circ}C$, with the pressure. These results can be explained to be attributed to the volume change of the hydrated ion due to the electrostriction. The volume change decreased with pressure due to an increase in the degree of the hydration.

A long duration of anticoagulant activity of acharan sulfate in vivo

  • Li, Da-Wei;Lee, In-Sun;Toshihiko Toida;Kim, Yeong-Shik
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.98.2-99
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    • 2003
  • Introduction: We previously reported that a new glycosaminoglycan, acharan sulfate (AS) from the African giant snail Achatina fulica showed anticoagulation activity in vitro, but it was much less than that of heparin. In the present study, the anticoagulant activity of AS was investigated in vivo. Methods: AS and heparin were administered to rats in various concentrations and anticoagulant activities were measured. Both were also compared in thrombin-induced Results: Intravenous administration of acharan sulfate prolonged the coltting time (APTT) in mice and rats in a dose-dependent manner. (omitted)

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The Role of Sphingosine-1-phosphate in Melanogenesis

  • Kim, Dong-Seok;Hwang, Eui-Soo;Lee, Jai-Eun;Kwon, Sun-Bang;Park, Kyoung-Chan
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.90.1-90.1
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    • 2003
  • This study shows that sphingosine-1-phosphate (S1P) significantly inhibits melanin synthesis in a concentration-dependent manner, and that the activity of tyrosinase was also reduced in S1P-treated cells. In contrast, a specific extracellular signal-regulated protein kinase (ERK) pathway inhibitor, PD98059 increased tyrosinase activity and melanin production, and PD98059 restored the reduced tyrosinase activity and pigmentation induced by SIP. We also found that S1P induces the sustained activation of ERK and the subsequent degradation of microphthalmia-associated transcription factor (MITF), which plays a key role in melanogenesis. (omitted)

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