• 한국축산식품학회지
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• 제32권5호
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• pp.545-552
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• 2012

This study evaluated the effects of NaCl on heat resistance and Caco-2 cell invasion of Listeria monocytogenes in broth media and sausage. A 10-strain mixture of L. monocytogenes was inoculated in tryptic soy broth containing 0.6% yeast extract (TSBYE), and sausage formulated with 0, 2, 4, and 6% NaCl. The medium was stored at 7, 15, 20, and $25^{\circ}C$ for 3-16 d, and medium samples were withdrawn at the appropriate time and challenged to 55, 60, and $63^{\circ}C$ to evaluate the thermal resistance of the pathogen. Sausage samples were stored at 7 and $25^{\circ}C$, and they were exposed to $63^{\circ}C$ to evaluate thermal resistance. NaCl-habituated L. monocytogenes strains NCCP10811 and NCCP10943 were examined for 12 antibiotics and Caco-2 cell invasion assay (only L. monocytogenes NCCP10943). Bacterial populations of L. monocytogenes generally increased (p<0.05) during the heat challenge as NaCl concentrations increased in both TSBYE and sausage samples. The antibiotic resistance of L. monocytogenes was not observed ($p{\geq}0.05$) when it was exposed to a single concentration of NaCl in TSBYE, but the pathogen obtained resistance to some antibiotics when exposed to a sequential increase of NaCl concentration. Invasion efficiency of L. monocytogenes NCCP10943 was not increased ($p{\geq}0.05$) with NaCl concentration increase. These results indicate that NaCl may increase the resistance of L. monocytogenes to heat and to some antibiotics, but may not increase Caco-2 cell invasion of L. monocytogenes.

• Journal of Microbiology and Biotechnology
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• 제31권2호
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• pp.250-258
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• 2021

Among various species of marine bacteria, those belonging to the genus Halomonas have several promising applications and have been studied well. However, not much information has been available on their antibiotic resistance. In our efforts to learn about the antibiotic resistance of strain Halomonas socia CKY01, which showed production of various hydrolases and growth promotion by osmolytes in previous study, we found that it exhibited resistance to multiple antibiotics including kanamycin, ampicillin, oxacillin, carbenicillin, gentamicin, apramycin, tetracycline, and spectinomycin. However, the H. socia CKY01 resistance pattern to kanamycin, gentamicin, apramycin, tetracycline, and spectinomycin differed in the presence of 10% NaCl and 1% NaCl in the culture medium. To determine the mechanism underlying this NaCl concentration-dependent antibiotic resistance, we compared four aminoglycoside resistance genes under different salt conditions while also performing time-dependent reverse transcription PCR. We found that the aph2 gene encoding aminoglycoside phosphotransferase showed increased expression under the 10% rather than 1% NaCl conditions. When these genes were overexpressed in an Escherichia coli strain, pETDuet-1::aph2 showed a smaller inhibition zone in the presence of kanamycin, gentamicin, and apramycin than the respective control, suggesting aph2 was involved in aminoglycoside resistance. Our results demonstrated a more direct link between NaCl and aminoglycoside resistance exhibited by the H. socia CKY01 strain.

• Corrosion Science and Technology
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• 제12권5호
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• pp.220-226
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• 2013

The uncertainty in statistical noise resistance measurement was evaluated for a type 316 stainless steel in NaCl solutions at room temperature. Sensitivity coefficients were determined for measurands or variables such as NaCl concentration, pH, solution temperature, surface roughness, inert gas flow rate and bias potential amplitude. The coefficients were larger for the variables such as NaCl concentration, pH, inert gas flow rate and solution temperature, and they were the major factors increasing the combined standard uncertainty of noise resistance. However, the contribution to the uncertainty in noise resistance measurement from the above variables was remarkably low compared to that from repeated measurements of noise resistance, and thus, it is difficult to lower the uncertainty in noise resistance measurement significantly by lowering the uncertainties related with NaCl concentration, pH, inert gas flow rate and solution temperature. In addition, the uncertainty in noise resistance measurement was high amounting to 17.3 % of the mean, indicating that the reliability in measurement of noise resistance is low.

• BMB Reports
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• 제30권1호
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• pp.21-25
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• 1997

The growth. freezing resistance and electrophoretic protein patterns of carrot callus cultures were investigated following treatment with NaCl for various' intervals at 20$^{\circ}C$. Following 7 day exposure to 250 mM NaCl. freezing tolerance increased, which was measured by 2.3.5-triphenyl tetrazolium chloride (TTC) assay and fresh weight was reduced compared to control cells. Changes of electrophoretic patterns of total and boiling stable proteins were investigated using one or two dimensional gel system. Several proteins with molecular weight of 43 and 21 kDa increased by NaCl treatment. The most prominent change was detected in 21 kDa protein. The steady state level of this protein increased in NaCl treated cells, but decreased in control cells. Twenty one kDa protein was detected only in the NaCl treated cell when boiling stable protein was analyzed. The isoelectric point of 21 kDa protein was identified as 5.7. The timing of increase of 21 kDa protein was correlated to freezing resistance which implied the role of this protein in the induction of freezing resistance of the cell.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.375-378
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• 2005

In this study, calcium chloride($CaCl_2$), sodium chloride (NaCl), organic acids-containing deicer(NS 40, NS 100), mixed deicier($NaCl\;70\%\;+\;CaCl_{2}\;30\%,\;NS\;40\;70\%\;+\;CaCl_{2}\;30\%,\;NaCl\;70\%\;+\;NS\;40\;30\%,\;NS\;40\;70\%\;+\;NaCl\;30\%$) is investigated based on the laboratory test for freez-thaw resistance of concrete and corrosion of metal. As a test results, in case of the use chloride-containing deicier in area that concrete structures has subjected to freez-thaw reaction in winter season, it showed desirable method that use deicing chemicals mixed with optimum ratio rather than use one deicing chemicals when is consider to deicing performance and effects, corrosion of steel materials, freez-thaw resistance of concrete. When use various deicing chemicals mixed, NS40($70\%$)+Calcium chloride($30\%$) showed the best effective method.

• Mycobiology
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• 제38권3호
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• pp.225-228
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• 2010

We studied the resistance of Cenococcum geophilum and Suillus granulatus isolates to NaCl during growth under axenic culture conditions. C. geophilum isolates displayed variations in NaCl resistance; mycelial growth of most isolates was inhibited above 200mM. All isolates of S. granulatus were tolerant to high NaCl content.

• Corrosion Science and Technology
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• 제18권3호
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• pp.110-116
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• 2019

Resistances to pitting corrosion of additive manufactured (AM) Ti-6Al-4V alloys in 0.6 M NaBr and 0.6 M NaCl aqueous solutions were compared using micro-droplet cell techniques. With respect to the pitting corrosion resistance, this study focused on two different types of halide anions in aqueous solutions, i.e. $Br^-$ and $Cl^-$. The differences between $Br^-$ and $Cl^-$ halide anions for breakdown on passive films of AM Ti-6Al-4V alloy were explained using Langmuir adsorption model with their equilibrium adsorption coefficients. The results of the analysis showed that the lower resistance to pitting potential of AM Ti-6Al-4V alloy in $Br^-$ aqueous solution was attributed to the higher equilibrium adsorption coefficient of Br-. In addition, micro-electrochemical test results showed that the pitting corrosion resistance of dark grains in additive manufactured Ti-6Al-4V alloy was lower as compared to that of bright grains due to the larger volume of ${\alpha}^{\prime}$ phase that caused the susceptibility to pit initiation.

• Journal of Forest and Environmental Science
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• 제31권4호
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• pp.312-316
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• 2015

Rhizina undulata, the causal agent of Rhizina root rot, is a soil-borne fungus occurring on coniferous trees. The destruction of coastal forests caused by R. undulata infection has been mainly associated with bonfires at camping sites. However, Rhizina root rot was observed in the western coastal forests without fire. It was hypothesized that Rhizina root rot in this area might be closely related to the soil salinity, which can facilitate the growth and survival of R. undulata. So, the variation in sodium chloride (NaCl) resistance among isolates of Rhizina undulata was compared using liquid media containing different concentrations of NaCl ranging from 0 mM to 300 mM. Our results showed that, albeit of no growth at a higher concentration of NaCl (300 mM), most of R. undulata isolates were capable of germinating and grew at up to 100 mM, indicating that NaCl resistance varies among R. undulata isolates. It was further found that isolates from coastal areas seemed to be more tolerant to NaCl than those further away the coast. We demonstrated that R. undulata could be possible to survive in coastal areas, but was lower NaCl tolerance than other fungi.

• Corrosion Science and Technology
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• 제8권5호
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• pp.193-196
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• 2009

For the estimation of uncertainty in potentiodynamic polarization resistance measurement, the type A uncertainty was measured using type 316 stainless steel in an acidified NaCl solution. Sensitivity coefficients were determined for measurand such as scan rate of potential, temperature of solution, concentration of NaCl, concentration of HCl, surface roughness of specimen and flow rate of purging gas. Sensitivity coefficients were large for the measurand such as the scan rate of potential, temperature of solution and roughness of specimen. However, the sensitivity coefficients were not the major factors influencing the combined standard uncertainty of polarization resistance due to the low values of uncertainty in measurements of the measurands. A major influencing factor was the concentration of NaCl. The value of type A uncertainty was 1.1 times the value of type B uncertainty, and the combined standard uncertainty was 10.5 % of the average value of polarization resistance.

• 한국지반공학회논문집
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• 제17권6호
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• pp.215-224
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• 2001

본 논문에서는 오염물질에 의해서 지반의 전기적 특성이 변한다는 원리에 의한 매립지의 침출수나 지하저장탱크의 유류 누출을 조기에 감지하는 시스템의 개발가능성을 확인하고자 하였다. 이를 위해 오염물질이 누출되는 상황을 모사한 실내실험을 통하여 전기저항 측정에 의한 오염물질 누출감지 가능성을 평가하였다. 불포화사질토 지반의 전기 저항 측정값은 함수비가 증가함에 따라 지수적으로 감소하는 경향을 보였다. 오염물질이 지반에 주입될 경우에 디젤은 비전도성 물질로 지반의 전기저항을 크게 증가시켰으며, NaCl 용액과 침출수는 전기전도성이 좋기 때문에 지반의 전기저항을 감소시켰다. 오염물질의 누출에 의한 전기저항은 측정전극간격에 따라 감지민감도가 다르게 나타났으며, 디젤의 경우에는 전극간격이 좁을수록, NaCl 용액과 침출수의 경우에는 전극간격이 높을수록 감지민감도가 크게 나타났다.