• 한국어병학회지
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• 제14권2호
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• pp.103-105
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• 2001

The effect of opsonization of zymosan with serum on the repiratory burst of haemocytes isolated from the Pacific oyster Crassostrea gigas was investigated. The reactive oxygen species (ROS) produced by the respiratory burst of haemocytes in response to the opsonized or unopsonized zymosan were measured using chemiluminescence (CL). The CL values were increased according to the increment of haemocyte number. The degree of CL amplification by increase of haemocytes from $0.1{\times}10^6$ to $0.5{\times}10^6$ cells/ml was 3-5 times, but comparatively low amplification was elicited by increase of haemocytes from $0.5{\times}10^6$ to $1{\times}10^6$ cells/ml. Chemiluminescences produced by the haemocytes in response to the zymosan opsonized with oyster serum were considerably higher than the CL produced by the haemocytes in response to the unopsonized zymosan.

• Bulletin of the Korean Chemical Society
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• 제29권9호
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• pp.1774-1780
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• 2008

New PVC based polymeric membrane electrodes (PME) and coated glassy carbon electrodes (CGCE) based on synthesized Schiff base complexes of Co(III); [Co(Salen)$(PBu_3)_2$]$ClO_4$, [Co($Me_2$Salen)$(PBu_3)_2$]$ClO_4$, [Co(Salen)$(PBu_3)H_2O$]$ClO_4$; as anion carriers for potentiometric determination of $ClO_4\;^-$were studied. The PME and also CGCE electrodes prepared with [Co(Me2Salen)$(PBu_3)_2$]$ClO_4$ showed excellent response characteristics to perchlorate ions. The electrodes exhibited Nernstian responses to $ClO_4\;^-$ ions over a wide concentration range with low detection limits ($1.0 {\times} 10^{-6}\;mol\;L^{-1}$ for PME and $9.0 {\times} 10^{-7}\;mol\;L^{-1}$ for CGCE). The electrodes possess fast response time, satisfactory reproducibility, appropriate lifetime and, most importantly, good selectivity toward $ClO_4\;^-$ relative to a variety of other common inorganic anions. The potentiometric response of the electrodes is independent of the pH in the pH range 2.5-8.5. The proposed sensors were used in potentiometric determination of perchlorate ions in mineral water and urine samples. The interaction of the ionophore with perchlorate ions was shown by UV/Vis spectroscopy.

• 대한화학회지
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• 제41권12호
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• pp.653-660
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• 1997

Tetradecyltrimethylammonium chloride(TDTMACl)을 첨가한 실리콘러버-지지체 전극막은 생체시료중 염화이온의 측정시 보다 향상된 전기화학적 특성을 나타내기 위하여 사용되었다. 이때 최적화된 전극막의 조성비는 95.4 wt% 실리콘러버, 4.6 wt% TDTMACl이며 이 전극막의 pH 감응성은 pH 6-10 영역에서 무시할 수 있었다. 이들 전극막들의 염화이온에 대해 감응기울기는 10-300 mM 영역에서 -3.75 mV/decade로 이론적인 Nernstian 감응기울기에는 못 미쳤으나 살리실레이트 이온 등 다른 음이온에 대한 선택성은 매우 우수하였다: KpotCl,NO3=1.3, KpotCl,I=2.0, KpotCl,Sal=0.8, KpotCl,SCN=2.0, KpotCl,ClO4=0.8. 또한 실리콘러버-지지체 전극막은 PVC-지지체 전국막에 비해 고체상 전극표면에 대한 접착력이 우수하므로 CWE형 고체상 전극에 도입되었을 때 향상된 전극수명을 나타내었다. 이들 고체상 전극들은 35일까지 염화이온에 대한 감응기울기나 살리실레이트 이온에 대한 감응성에 변화없이 우수하게 작동함을 알 수 있었다.

• 한국축산식품학회지
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• 제36권4호
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• pp.469-475
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• 2016

This study examined the relationship between NaCl sensitivity and stress response of Listeria monocytogenes. Nine strains of L. monocytogenes (NCCP10805, NCCP10806, NCCP10807, NCCP10808, NCCP10809, NCCP10810, NCCP10811, NCCP10920 and NCCP 10943) were exposed to 0%, 1%, 2% and 4% NaCl, and then incubated at 60℃ for 60 min to select strains that were heat-sensitized (HS) and non-sensitized (NS) by NaCl exposure. After heat challenge, L. monocytogenes strains were categorized as HS (NCCP 10805, NCCP10806, NCCP10807, NCCP10810, NCCP10811 and NCCP10920) or NS (NCCP10808, NCCP10809 and NCCP10943). Total mRNA was extracted from a HS strain (NCCP10811) and two NS strains (NCCP10808 and NCCP10809), and then cDNA was prepared to analyze the expression of genes (inlA, inlB, opuC, betL, gbuB, osmC and ctc) that may be altered in response to NaCl stress, by qRT-PCR. The expression levels of two invasion-related genes (inlA and inlB) and two stress response genes (opuC and ctc) were increased (p<0.05) in NS strains after NaCl exposure in an NaCl concentration-dependent manner. However, only betL expression was increased (p<0.05) in the HS strains. These results indicate that the effect of NaCl on heat sensitization of L. monocytogenes is strain dependent and that opuC and ctc may prevent NS L. monocytogenes strains from being heat sensitized by NaCl. Moreover, NaCl also increases the expression of invasion-related genes (inlA and inlB).

• Journal of Microbiology and Biotechnology
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• 제17권4호
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• pp.644-649
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• 2007

Response surface model was developed for predicting the growth rates of Salmonella enterica sv. Typhimurium in tryptic soy broth (TSB) medium as a function of combined effects of temperature, pH, and NaCl. The TSB containing six different concentrations of NaCl (0, 2, 4, 6, 8, and 10%) was adjusted to an initial of six different pH levels (pH 4, 5, 6, 7, 8, 9, and 10) and incubated at 10 or $20^{\circ}C$. In all experimental variables, the primary growth curves were well $(r^2=0.900\;to\;0.996)$ fitted to a Gompertz equation to obtain growth rates. The secondary response surface model for natural logarithm transformations of growth rates as a function of combined effects of temperature, pH, and NaCl was obtained by SAS's general linear analysis. The predicted growth rates of the S. Typhimurium were generally decreased by basic (9, 10) or acidic (5, 6) pH levels or increase of NaCl concentrations (0-8%). Response surface model was identified as an appropriate secondary model for growth rates on the basis of coefficient determination $(r^2=0.960)$, mean square error (MSE=0.022), bias factor $(B_f=1.023)$, and accuracy factor $(A_f=1.164)$. Therefore, the developed secondary model proved reliable predictions of the combined effect of temperature, NaCl, and pH on growth rates for S. Typhimurium in TSB medium.

• The Korean Journal of Physiology and Pharmacology
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• 제2권4호
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• pp.521-527
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• 1998

An important property of the intestine is the ability to secrete fluid. The intestinal secretion is regulated by a number of substances including vasoactive intestinal peptide (VIP), ATP and different inflammatory mediators. One of the most important secretagogues is adenosine during inflammation. However, the controversy concerning the underlying mechanism of adenosine-stimulated $Cl^-$ secretion in intestinal epithelial cells still continues. To investigate the effect of adenosine on $Cl^-$ secretion and its underlying mechanism in the rabbit colon mucosa, we measured short circuit current ($I_{SC}$) under automatic voltage clamp with DVC-1000 in a modified Ussing chamber. Adenosine, when added to the basolateral side of the muocsa, increased $I_{SC}$ in a dose-dependent manner. The adenosine-stimulated $I_{SC}$ response was abolished when $Cl^-$ in the bath solution was replaced completely with gluconate. In addition, the $I_{SC}$ response was inhibited by a basolateral Na-K-Cl cotransporter blocker, bumetanide, and by apical $Cl^-$ channel blockers, dephenylamine-2-carboxylate (DPC), 5-nitro-2-(3-phenyl-propylamino)-benzoate (NPPB), glibenclamide. Amiloride, an epithelial $Na^+$ channel blocker, and 4,4-diisothiocyanato-stilbene-2,2-disulphonate (DIDS), a $Ca^{2+}-activated$ $Cl^-$ channel blocker, had no effect. In the mucosa pre-stimulated with forskolin, adenosine did not show any additive effect, whereas carbachol resulted in a synergistic potentiation of the $I_{SC}$ response. The adenosine response was inhibited by 10 ${\mu}M$ H-89, an inhibitor of protein kinase A. These results suggest that the adenosine-stimulated $I_{SC}$ response is mediated by basolateral to apical $Cl^-$ secretion through a cAMP-dependent $Cl^-$ channel. The rank order of potencies of adenosine receptor agonists was $5'-(N-ethylcarboxamino)adenosine(NECA)＞N^6-(R-phenylisopropyl)adenosine(R-$ PIA)＞2-[p-(2-carbonylethyl)-phenyl-ethylamino]-5'-N-ethylcarboxaminoadenosine(CGS21680). From the above results, it can be concluded that adenosine interacts with the $A_{2b}$ adenosine receptor in the rabbit colon mucosa and a cAMP-dependent signalling mechanism underlies the stimulation of $Cl^-$ secretion.

• Fisheries and Aquatic Sciences
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• 제3권1호
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• pp.23-25
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• 2000

To compare the respiratory burst activity potential of the phagocytes isolated from head kidney, spleen, and peripheral blood 1ll cultured rockfish (Sebastes schlegeli), chemiluminescent (CL) response analysis was performed. The phagocytes isolated from peripheral blood showed greater and faster CL response to the opsonized zymosan compared to that of the phagocytes isolated from kidney or spleen. This may imply a significant role of the blood phagocytes in defence mechanism of rockfish. The different responses found in the CL analysis among the phagocytes isolated from peripheral blood, kidney, and spleen may reflect differences in activation state or activity of phagocytes.

• 한국식품영양과학회지
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• 제22권1호
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• pp.101-107
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• 1993

Zygosaccharomyces rouxii는 간장의 숙성 기간동안 중요한 역활을 하는 내염성 효모이다. 이 실험에서 사용된 Z. rouxii는 18% NaCl함유 YPD (1% yeast extract, 2% peptone과 2% glucose, pH5.0)에서 잘 성장하는 반면 Saccharomyces cerevisiae는 8% NaCl보다 적은 YPD에서만 자란다 15% NaCl존재하에서 Z. rouxii는 대수기에서 세포내에서 적합한 용질로서 많은 양의 글리세린을 축적하는데 이것은 내염성 효모의 특성이다. 세포막 지질 유동층의 화학 분석에 따르면 15% NaCl에서 자란 세포의 막구조는 더욱 단단하였고 그 유동층은 고농도의 식염의 배지에서는 세포내에 글리세린이 감소되었다.

• Bulletin of the Korean Chemical Society
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• 제25권10호
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• pp.1484-1488
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• 2004

The thiocyanate-selective PVC membrane electrodes based on 5,10,15,20-tetrakis(2,4,6-trimethylphenyl)-porphyrinatomanganese(III) chloride [Mn(TMP)Cl] and 5,10,15,20-tetrakis(2,6-dichlorophenyl)porphyrinatomanganese(III) chloride $[Mn(Cl_8TPP)Cl]$ as ion carriers were investigated. The effect of ionophores, membrane compositions, plasticizers, and solution pHs on the response characteristics were studied. The Mn(TMP)Cl as an ionophore shows the best potentiometric sensitivity with a slope of -58.7 mV/decade and a detection limit of $log[SCN^-]$ = -6.90, and selectivity for thiocyanate over strong hydrophobic interfering anions such as ${ClO_4}^-$ and salicylate. The potentiometric response is affected by the electronic effect of the substituents and solution pHs. The presence of substituents with electron donating and more liphophilic characters around the ligated metal center produces an improved response toward $SCN^-$.

• 생명과학회지
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• 제12권6호
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• pp.765-768
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• 2002

Rhodotorula sp. CL-82 유래 의 epoxide hydrolase 활성을 이용하여 라세믹 styrene oxide에 대한 입체선택적 가수분해 반응을 실시하였다. Rhodotorula sp. CL-82 생촉매의 입체선택적 가수분해속도를 나타내주는 반응표면 곡선에 대한 분석을 통해 pH, 반응주도, cosolvent 첨가량에 대한 최적조건을 각각 7.6,$33.3^{\circ}C$ , 3%(v/v)으로 결정하였다. 최적반응조건에서 약 4시간 정도의 반응을 통해 ee값이 99% 이상인 광학적으로 순수한 (S)-styrene oxide를 이론 수율대비 40% 수율로 얻을 수 있었다.