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Isolation and Characterization of 3,4-Dichloroaniline Degrading Bacteria (3,4-Dichloroaniline 분해 미생물의 분리 및 특성)

  • Kim, Young-Mog;Park, Kun-Ba-Wui;Kim, Won-Chan;Han, Won-Sub;Yu, Choon-Bal;Rhee, In-Koo
    • Microbiology and Biotechnology Letters
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    • v.35 no.3
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    • pp.245-249
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    • 2007
  • Chloroanilines are widely used in the production of dyes, drugs and herbicides. Chloroanilines, however, are considered potential pollutants due to their toxic and recalcitrant properties to humans and other species. With the increase of necessity of bioremediation, this study was conducted to isolate the chloroanilines-degrading bacteria. A bacterium capable of growth on 3,4-dichloroaniline (DCA) was isolated by the 3,4-DCA-containing enrichment culture. The strain KB35B was identified as Pseudomonas sp. and also able to degrade several chloroanilines. The isolated strain showed high level of catechol 2,3-dioxygenase activity in the presence of 3,4-DCA. The activity of catecho1 2,3-dioxygenase was supposed to be ones of the important factors for 3,4-DCA degradation. The activity toward 4-methykatechol was 60.6% of that of catechol, while the activity toward 3-methylcatechol and 4-chlorocatechol were 27.0 and 13.5%, respectively.

Purification and Characterization of Thermostable Agarase from Bacillus sp. BI-3, a Thermophilic Bacterium Isolated from Hot Spring

  • Li, Jiang;Sha, Yujie;Seswita-Zilda, Dewi;Hu, Qiushi;He, Peiqing
    • Journal of Microbiology and Biotechnology
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    • v.24 no.1
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    • pp.19-25
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    • 2014
  • An extracellular agarase was purified from Bacillus sp. BI-3, a thermophilic agar-degrading bacterium isolated from a hot spring in Indonesia. The purified agarase revealed a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, with an apparent molecular mass of 58 kDa. The optimum pH and temperature of the agarase were 6.4 and $70^{\circ}C$, respectively. The activity of the agarase was stable at high temperatures, and more than 50% activity was retained at $80^{\circ}C$ for 15 min. Furthermore, the enzyme was stable in the pH range of 5.8-8.0, and more than 60% of the residual activity was retained. Significant activation of the agarase was observed in the presence of $K^+$, $Na^+$, $Ca^{2+}$, $Mg^{2+}$, and $Sr^{2+}$; on the other hand, $Ba^{2+}$, $Zn^{2+}$, $Cu^{2+}$, $Mn^{2+}$, $Co^{2+}$, $Fe^{2+}$, and EDTA inhibited or inactivated the enzyme activity. The components of the hydrolytic product analyzed by thin-layer chromatography showed that the agarase mainly produced neoagarobiose. This study is the first to present evidence of agarolytic activity in aerobic thermophilic bacteria.

Evaluation of the Effect of the Discharged Water from Bong Stream after Rainfall Events on the Bacteriological Water Quality in Gangjinman, Korea (강우 발생에 따른 남해군 봉천 방출수가 강진만 해역의 세균학적 수질에 미치는 영향 평가)

  • Park, Kun-Ba-Wui;Jo, Mi-Ra;Lee, Hee-Jung;Kwon, Ji-Young;Son, Kwang-Tae;Lee, Tae-Seek
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.44 no.6
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    • pp.622-629
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    • 2011
  • We investigated the effect of the discharged water from Bong Stream, which is located in the drainage area of Gangjinman area on the bacteriological water quality in the coastal area after rainfall events. Following 12.5 mm of rainfall, water discharged from Bong Stream had a very limited effect on bacteriological water quality in adjacent area and the affected area did not extend to the designated area. On the other hand, after 23 mm rainfall, the density of fecal coliform at stations located in the designated area was higher than at stations located in the adjacent area. The degree of bacteriological contamination at the surveyed stations in the coastal area after rainfall events did not show a relationship with distance from the shoreline. These results indicate that the direction of spread and the range of contaminants from the drainage area were affected by tides at the time of the survey. Therefore, a detailed survey of the effects of tides on the diffusion characteristics of the contaminants from Bong Stream is needed to establish a proper management plan for the surveyed area.

Formation of a Unique 1:2 Calcium-Calixquinone Complex in Aqueous Media

  • Kang, Sun-Kil;Lee, One-Sun;Chang, Suk-Kyu;Chung, Doo-Soo;Kim, Ha-Suck;Chung, Taek-Dong
    • Bulletin of the Korean Chemical Society
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    • v.32 no.3
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    • pp.793-799
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    • 2011
  • We report the complexation behavior of calix[4]arenemonoquinone-triacid (CTAQ), which is an electroactive and water-soluble receptor for calcium ion. UV-visible and NMR spectroscopic studies revealed that CTAQ in aqueous media forms 1:2 as well as 1:1 (metal ion:CTAQ) stoichiometric complexes with $Ca^{2+}$, $Sr^{2+}$, and $Ba^{2+}$ ions. The nonlinear fitting of titration curves based on UV-visible absorption spectra showed that the binding constants of CTAQ for $Ca^{2+}$ ion are 4 $({\pm}2){\times}10^6\;M^{-1}$ for 1:1 and 1.4 $({\pm}0.5){\times}10^{11}\;M^{-2}$ for 1:2 complex. NMR conformational studies and the titration curves corroborate that the $Ca^{2+}$:CTAQ complex in aqueous solution is not present in the form of merely 1:1 one, being consistent with UV-visible spectrophotometric results. The Monte Carlo simulation supports the presence of a stable conformer of 1:2 complexes in which a $Ca^{2+}$ ion is interposed between two CTAQs at the global minimum. This is the first model of 1:2 stoichiometric complex of calix[4]arene and alkaline earth ions in aqueous media.

Effects of Wounding and Jasmonic Acid on Polyphenol Oxidase in Tomato Seedlings (토마토 유식물의 Polyphenol Oxidase에 미치는 상해 및 Jasmonic Acid의 영향)

  • Jin Sun-Young;Hong Jung-Hee
    • Journal of Environmental Science International
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    • v.8 no.6
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    • pp.669-676
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    • 1999
  • The effects of wounding and jasmonic acid(JA) on polyphenol oxidase(PPO) in tomato(Lycopersicon esculentum Mill.) seedlings were investigated. PPO was strongly induced by wounding or JA, and the response was also shown to be systemically induced by wounding. Mechanical wounding in cotyledon or leaf produced a signal that caused the concentration of PPO to increase in the unwounded cotyledon, in the first leaves but not in the second leaves. Severity of wounding and light intensity also affected wound induced change in PPO activity, JA showed a stimulatory effect on the loss of chlorophyll and the rapid increase in PPO activity. The PPO was clearly more active in the wounded leaves than in controls. The potency and specificity of the JA indicate a close relationship between JA and wound-induced changes in PPO in tomato species. JA and abscisic acid(ABA) acted similarly on both unwounded and wounded leaves, but the amount of PPO in the wounded leaves was always more than the respective controls. The highest increase in PPO activity occurred in woundand JA-induced leaves of seedlings kept under bright lighting. Benzyladenine(BA) completely abolished JA- and ABA-induced PPO activity. The results suggest that JA-induced PPO activity is due to de novo PPO synthesis. Histochemical tests for PPO in stems of wound- and JA -treated tomato plants indicate that PPO was localized primarily, in the. outer .cortex . and xylem parenchyma. It is concluded that exogenously applied JA acts as stress agents and PPO may be a component of the inducible anti-hervivore defense response.

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Effects of Seungseup-tang on MIA-induced Osteoarthritis Rats (승습탕(勝濕湯)이 MIA로 유발된 골관절염 흰쥐에 미치는 영향)

  • Lee, Jong-Hoon;Woo, Chang-Hoon;Kim, Young-Jun;Ahn, Hee-Duk
    • Journal of Korean Medicine Rehabilitation
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    • v.26 no.3
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    • pp.1-15
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    • 2016
  • Objectives This study was designed to evaluate the anti-inflammatory effects of Seungseup-tang (SST) on the monosodium iodoacetate (MIA)-induced osteoarthritis rats. Methods Osteoarthritis was induced by injection of MIA ($50{\mu}l$ with 80 mg/ml) into knee joint cavity of rats. Rats were divided into 4 groups (normal group, control group, indomethacin treated group, SST treated group, each n=6). Normal group was not injected with MIA and taken normal diet. Control group was injected with MIA and taken with distilled water. Indomethacin treated group was injected with MIA and taken indomethacin 5 mg/kg by oral administration. SST treated group was injected with MIA and taken SST 200 mg/kg by oral administration. We examined the weight-bearing ability of hind paw, biomarkers related to oxidative stress in serum, inflammatory proteins and inflammatory mediators and cytokines. Moreover, histopathological examination of knee joint structure was also performed by Hematoxylin & Eosin (H&E), Safranin-O staining method. Results In the present study, SST treated group showed a similar inhibitory effects alike indomethacin treated group, in most of the studied parameters of inflammation. The increased oxidative stress biomarker such as reactive oxygen species (ROS) and peroxy nitrite ($ONOO^-$) in the serum were reduced with SST. Especially, the level of $ONOO^-$ compared with control group significantly suppressed. Also, the expression of inflammatory mediators and cytokines induced by nuclear factor-kappa B (NF-${\kappa}B$) activation was modulated through inhibition of IkBa phosphorlation. In addition, histological analysis revealed that cartilage damage by MIA repaired markedly in SST treated group. Conclusions According to the results, Seungseup-tang may be effective for preventing the progression of osteoarthritis.

Antibacterial potential of the extracts derived from leaves and in vitro raised calli of medicinal plants Pterocarpus marsupium Roxb., Clitoria ternatea L., and Sanseveiria cylindrica Bojer ex Hook

  • Shahid, M;Shahzad, A;Anis, M
    • Advances in Traditional Medicine
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    • v.9 no.2
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    • pp.174-181
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    • 2009
  • Pterocarpus marsupium, Clitoria ternatea, and Sanseveiria cylindrica are some of the important and endangered medicinal plant species of India. Despite of medicinal properties, antibacterial potential of the plants have not yet been explored. The present study was designed to optimize the in vitro technique for micropropagation and to screen the extracts from leaves and in vitro raised calli for antibacterial properties. Excised leaf-explants from the parent plants were surface sterilized and cultivated on Murashige & Skoog's (MS) medium containing $N^6$-benzyladenine (BA) in concentrations of 1, 2, 5, and $10{\mu}M$. Optimal growth of calli was noticed at a concentration of $5{\mu}M$, therefore the extracts from calli grown at this concentration were further studied for antibacterial activity. Both alcoholic and aqueous extracts from leaves of respective plants, and their in vitro raised calli were tested for antibacterial activity by agar well diffusion method against a range of Gram-positive and Gram-negative bacteria. Aqueous extracts showed antibacterial activity against limited number of bacterial species; notably the extracts of C. ternatea which showed antibacterial activity against Streptococcus pyogenes, Bacillus subtilis and Bacillus cereus. Alcoholic extracts of all three plants showed antibacterial activity against a wider range of bacteria. Among the Gram-positive bacteria, extracts from C. ternatea showed strong antibacterial activity against Bacillus spp., whereas the extracts of S. cylindrica showed good antibacterial potential for Staphylococcus aureus, S. epidermidis and S. pyogenes. The extracts from all three plants showed antibacterial activity against Gram-negative bacteria, including, Salmonella spp. and Shigella dysenteriae; organisms causing enteric fever and dysentery. In most of the cases, the extracts from respective calli showed comparable, and in some cases better, result in comparison to the extracts from parent leaves. To the best of our knowledge this is the first preliminary report on antibacterial potential, especially through calli extracts, of these plants; and in vitro cultivation of the explants may be used to obtain phytotherapeutic compounds.

Dissociation of the semantic and syntactic processing reflected on fMRI in Korean sentences (기능적 자기공명영상에 나타난 한글 의미.통사 문장 처리의 해리)

  • Lee, Hong-Jae;Lee, Dong-Hoon;Nam, Ki-Chun;Lee, Eun-Jung;Moon, Chan-Hong;Ryoo, Jae-Wook;Na, Dong-Gyu
    • Annual Conference on Human and Language Technology
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    • 2000.10d
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    • pp.405-410
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    • 2000
  • 본 연구에서는 기능적 자기공명영상을 이용하여 한글 문장의 의미와 통사 처리에 관한 뇌의 활성화 양상을 비교함으로써 한글문장 이해의 과정에 대한 신경해부학적 증거를 찾고자 하였다. 6명의 자원자를 대상으로 문장진위판단과제를 이용하여 활성화를 유도하였다. 1.5T 초전도 자기공명영상 장치에서 EPI로 BOLD 기법을 이용하여 기능적 영상을 얻었으며 영상 후 처리는 SPM99 분석 프로그램을 이용하였다. 의미관련 통사관련 문장 모두에서 좌 우 전두회(frontal gyrus) 영역에서 활성화되었다. 의미와 통사처리 영역을 구분하기 위하여 감산법을 적용한 결과, 의미처리는 좌반구의 중측두회(middle temporal gyrus) 영역에서, 통사처리는 우반구의 하전두회(BA44) 부위에서 더 많이 활성화되었다. 의미처리에서 더 우세한 성향을 띠는 부위로 밝혀진 중측두회 영역은 의미처리시에 활성화되는 영역으로 보고하는 기존의 연구와 일치하는 결과이다. 의미와 통사 문장처리시의 뇌 활성화 양상은 뇌의 여러 영역에서 중첩되어 있기는 하지만, 특정영역에서의 차이를 보이고 있으므로, 의미와 통사처리는 다른 기전(mechanism)에 의해서 일어남을 시사해 준다.

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MOCVD 법에 의한 Ruthenium 박막의 증착 및 특성 분석

  • 강상열;최국현;이석규;황철성;석창길;김형준
    • Proceedings of the Korean Vacuum Society Conference
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    • 1999.07a
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    • pp.152-152
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    • 1999
  • 1Gb급 이상 기억소자의 캐패시터 재료로 주목받고 있는 (Ba,Sr)TiO3 [BST] 박막의 전극재료로는 Pt, Ru, Ir과 같은 금속전극과 RuO2, IrO2와 산화물 전도체가 유망한 것으로 알려져 있다. 그런데, DRAM의 집적도가 증가하게 되면, BST같은 고유전율 박막을 유전재료로 사용한다 하더라도, 3차원적인 구조가 불가피하게 때문에 기존의 sputtering 방법으로는 우수한 단차피복성을 얻기 힘들므로, MOCVD법이 필수적이다. 본 연구에서는 기존에 연구되었던 Pt에 비해 식각특성이 우수하고, 비교적 낮은 비저항을 갖는 Ru 박막증착에 대한 연구를 행하였다. 본 연구에서는 수직형의 반응기와 저항 가열 방식의 susceptor로 구성된 저압 유기금속 화학증착기를 사용하여 최대 6inch 직경을 갖는 기판 위에 Ru박막을 증착하였다. Precursor로는 기존에 연구된 적이 없는 bis-(ethyo-$\pi$-cyclopentadienyl)Ru (Ru(C5H4C2H5)2, [Ru(EtCp)2])를 사용하였으며, bubbler의 온도는 85$^{\circ}C$로 하였다. Si, SiO2/Si를 사용하였으며, 증착온도 25$0^{\circ}C$~40$0^{\circ}C$, 증착압력 3Torr의 조건에서 Ru 박막을 증착하였다. Presursor를 운반하는 수송기체로는 Ar을 사용하였으며, carbon과 같은 불순물의 제거를 위해 O2를 첨가하였다. 증착된 박막은 XRD, SEM, 4-point probe등을 통해 구조적, 전기적 특성을 평가하였으며, 열역학 계산을 위해서는 SOLGASMIX-PV프로그램을 사용하였다. Ru 박막의 증착에 있어서 산소의 첨가는 필수적이었으며, Ru 박막의 증착속도는 30$0^{\circ}C$~40$0^{\circ}C$의 온도 영역에서 200$\AA$/min으로 일정하였으며, 첨가된 산소의 양이 적을수록 더 치밀하고 평탄한 표면형상을 보였으며, 또한 더 낮은 전기 전도도를 보였다. 그리고 증착된 박막은 12~15$\mu$$\Omega$cm 정도의 낮은 비저항 값을 나타냈으며 이것은 기존의 sputtering 법에 의해 증착된 Ru 박막의 비저항 값들과 비교될만하다. 한편, 높은 온도, 높은 산소분압 조건에서 RuO2의 형성을 관찰하였으며, 이것은 열역학적인 계산을 통해서 잘 설명할 수 있었다.

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Progress in R&D of coated conductor in M-PACC project

  • Izumi, T.;Ibi, A.;Nakaoka, K.;Taneda, T.;Yoshida, T.;Takagi, Y.;Nakamura, T.;Machi, T.;Katayama, K.;Sakai, N.;Yoshizumi, M.;Koizumi, T.;Kimura, K.;Kato, T.;Kiss, T.;Shiohara, Y.
    • Progress in Superconductivity and Cryogenics
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    • v.16 no.2
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    • pp.1-6
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    • 2014
  • The five-year national project in Japan for R&D of coated conductors and applications, named as the Materials and Power Applications of Coated Conductors (M-PACC) project, was finished at the end of FY2013. The project consists of four sub-themes as cable, transformer, SMES and coated conductors. In the theme of coated conductors, the fabrication process had been developed to satisfy the requirements from the applications such as in-field $I_c$ performance, low AC loss in the long tapes etc. Through the project, the remarkable progress was achieved as follows; a high in-field minimum $I_c$ value over 54A/cm-width under 3T at 77K was realized in a 200m long EuBCO tape with artificial pinning centers of $BaHfO_3$ by the pulsed laser deposition (PLD) technique on the IBAD template. On the other hand, the AC loss reduction was confirmed in the tapes fabricated by both PLD and the metal organic deposition (MOD) techniques by scribing 100m tapes into 10-filamments. Additionally, the mechanism of the delamination phenomenon was systematically investigated and the strength was improved by eliminating the origins of the weak points in the films. Through the development, all targeted goals were accomplished and the several results were appreciated as a world champion data.