• The Korean Journal of Physiology
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• 제25권2호
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• pp.179-188
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• 1991

Effect of a sulfhydryl reagent, p-chloromercuribenzoic acid (PCMB), on the transport of succinate was studied in brush border (BBMV) and basolateral (BLMV) membrane vesicles isolated from rabbit renal cortex. PCMB induced an irreversible inhibition of the $Na^+-dependent$ succinate uptake in a dose-dependent manner with $IC_{50}$ of 55 and $65\;{\mu}M$ in BBMV and BLMV, respectively. The inhibitory effect of PCMB was prevented by a pretreatment of vesicles with dithiothreitol. PCMB did not increase $Na^+$ permeability at concentrations inhibiting succinate uptake. The PCMB inhibition of succinate uptake was due to a change in Vmax, but not in Km. When membrane vesicles were pretreated with PCMB in the presence of unlabelled succinate, the inhibitory effect was significantly reduced. In both BBMV and BLMV, succinate uptake was inhibited by various sulfhydryl reagents with the inhibitory potency of following order: $HgCl_2$>DTNB>PCMBS>PCMB. These results suggest that sulfhydryl groups are essential for dicarboxylate transport and that they may be located at or near substrate binding sites of the transporters in renal brush border and basolateral membranes.

• Corrosion Science and Technology
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• 제22권2호
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• pp.90-98
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• 2023

In this study, cobalt oxide (Co₃O₄) and cobalt-doped magnetite (CoFe₂O₄) nanoparticles were synthesized by a hydrothermal method. They were then used as corrosion inhibitors for corrosion protection of AA2024-T3 aluminum alloys. These obtained nanoparticles were characterized by x-ray diffraction, field-emission scanning electron microscopy, and Zeta potential measurements. Corrosion inhibition activities of Co₃O₄ and CoFe₂O₄ nanoparticles were determined by performing electrochemical measurements for bare AA2024-T3 aluminum alloys in 0.05 M NaCl + 0.1 M Na₂SO₄ solution containing Co₃O₄ or CoFe₂O₄ nanoparticles. Corrosion protection for AA2024-T3 aluminum alloys by a water-based epoxy with or without the synthesized Co₃O₄ or CoFe₂O₄ nanoparticles was investigated by electrochemical impedance spectroscopy during immersion in 0.1 M NaCl solution. The corrosion protection of epoxy coating deposited on the AA2024-T3 surface was improved by incorporating Co₃O₄ or CoFe₂O₄ nanoparticles in the coating. The corrosion protection performance of the epoxy coating containing CoFe₂O₄ was higher than that of the epoxy coating containing Co₃O₄.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.194-194
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• 2017

Camelina (Camelina sativa L.) is a potential bio-energy crop that has short life cycle about 90 days and contains high amount of unsaturated fatty acid which is adequate to bio-diesel production. Enhancing environmental stress tolerance is a main issue to increase not only crop productivity but also big mass production. CsRCI2s (Rare Cold Inducible 2) are cold and salt stress related protein that localized at plasma membrane (PM) and assume to be membrane potential regulation factor. These proteins can be divide into C-terminal tail (CsRCI2D/E/F/G) or no-tail group (CsRCI2A/B/C/H). However, function of CsRCI2s are less understood. In this study, physiological responses and functional characterization of CsRCI2s of Camelina under salt stress were analyzed. Full-length CsRCI2s (A/B/E/F) and CsPIP2;1 sequences were confirmed from Camelina genome browser. Physiological investigations were carried out using one- or four-week-old Camelina under NaCl stress with dose and time dependent manner. Transcriptional changes of CsRCI2A/B/E/F and CsPIP2;1 were determined using qRT-PCR in one-week-old Camelina seedlings treated with NaCl. Translational changes of CsRCI2E and CsPIP2;1 were confirmed with western-blot using the antibodies. Water transport activity and membrane potential measurement were observed by cRNA injected Xenopus laevis oocyte. As results, root growth rate and physiological parameters such as stomatal conductance, chlorophyll fluorescence, and electrolyte leakage showed significant inhibition in 100 and 150 mM NaCl. Transcriptional level of CsPIP2;1 did not changed but CsRCI2s were significantly increased by NaCl concentration, however, no-tail type CsRCI2A and CsRCI2B increased earlier than tail type CsRCI2E and CsRCI2F. Translational changes of CsPIP2;1 was constitutively maintained under NaCl stress. But, accumulation of CsRCI2E significantly increased by NaCl stress. CsPIP2;1 and CsRCI2A/B/E/F co-expressed Xenopus laevis oocyte showed decreased water transport activity as 61.84, 60.30, 62.91 and 76.51 % at CsRCI2A, CsRCI2B, CsRCI2E and CsRCI2F co-expression when compare with single expression of CsPIP2;1, respectively. Moreover, oocyte membrane potential was significantly hyperpolarized by co-expression of CsRCI2s. However, higher hyperpolarized level was observed in tail-type CsRCI2E and CsRCI2F than others, especially, CsRCI2E showed highest level. It means transport of $Na^+$ ion into cell is negatively regulated by expression of CsRCI2s, and, function of C-terminal tail is might be related with $Na^+$ ion influx. In conclusion, accumulation of NaCl-induced CsRCI2 proteins are related with $Na^+$ ion exclusion and prevent water loss by CsPIP2;1 under NaCl stress.

• 인간식물환경학회지
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• 제23권4호
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• pp.445-453
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• 2020

Background and objective: Calcium chloride (CaCl₂) and sodium chloride (NaCl) are commonly used as a deicing agent in South Korea and penetrate the soil on the roadside, causing damage to plants. This study was conducted to investigate the salinity reduction effect of Pennisetum alopecuroides and the chemical characteristics of soil leachate. Methods: The plants were treated with five different concentrations of CaCl₂ (0, 1, 2, 5, and 10g·L^-1) and were grouped into the Cont., C1, C2, C5, and C10 groups. CaCl₂ of 200 m·L^-1 was sprayed to each plant once every two weeks. The growth of P. alopecuroides (plant height, leaf length, leaf width and the number of leaves) was measured. The level of EC and pH, and exchangeable cations (K⁺, Ca²⁺, Na⁺, and Mg²⁺) in the leachate of soil was monitored. Results: The pH of soil leachate decreased as the CaCl₂ concentration increased, and the EC increased significantly. The content of K⁺ did not change significantly until the concentration of CaCl₂ reached 5 g·L^-1, but the content of Ca²⁺, Na⁺, and Mg²⁺ significantly increased. The plant height, leaf length, and leaf width of P. alopecuroides showed the highest value in CaCl₂ 1 g·L^-1 followed by CaCl₂ 2 g·L^-1 and the control group. Root fresh weight was the highest in CaCl₂ 2 g·L^-1. On the other hand, there was no change in the shoot fresh weight, dry weight and root dry weight, and P. alopecuroides growth inhibition at the concentration of 5 g·L^-1 or higher in the plant height and leaf length. Conclusion: P. alopecuroides is relatively highly salt-tolerant and can improve the salt damaged soil by lowering the content of the salt-based exchangeable K⁺ ions.

• 생명과학회지
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• 제18권6호
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• pp.789-795
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• 2008

어류 질병 치료를 위한 probiont의 개발에 목적을 두고 어병균 Vibrio anguillarum NCMB1의 생육에 저해물질을 생산하는 Bacillus amyloliquefaciens H41균주를 분리하고 이 물질의 특성을 규명하기 위하여 정제를 시행하였다. 분리 균을 배양한 배양 상등액을 70% 염석, 투석하여 조 효소액으로 제작하고 조 효소액을 DEAE-sephadex, A-50 ion exchange chromatography, sephadex G-200 gel filtration column chromatography을 통하여 정제하고 SDS-PAGE 를 통하여 단일밴드를 확인하고 최종 회수율 2.9%을 얻을 수 있었으며 40.8배의 정제된 V. anguillarum NCMB1 생육저해물질을 얻을 수 있었다. 정제된 저해물질은 저해정도에 따라 단위를 설정하여 활성을 측정하였으며, 분자량은 48 kDa 로 확인되었으며 정제물질의 활성을 위한 최적 반응 pH와 온도는 pH 7.5와 $30^{\circ}C$로 확인되었다. 금속이온의 효과에 있어서는 $CoCl_2$, $HgCl_2$, $ZnSO_4$, $AgNo_3$에서는 완전히 저해되는 양상을 나타내었고 $MgSO_4$, $MnSO_4$에서 미미한 효소활성의 증가를 나타내었다. 그리고 염에 관한 안정성은 일반 해수의 농도인 3%의 농도에서도 활성을 나타내는 것으로 확인되었다. 정제된 저해물질을 현재 상업적으로 사용하고 있는 화학처리제나 항생제와 함께 효율성을 비교 해 보았을 때 저해물질은 약 78%의 저해 활성을 나타내는 것을 알 수 있었고 항생제보다는 효율성이 낮았으나 독성검사를 위해 정제물질을 살아있는 어류에 투여하였으나 어떤 해수어도 폐사하지 않는 것으로 보아 어류 자체엔 독성을 나타내지 않는 물질로 나타났다. 따라서 B. amyloliquefaciens H41 균주가 생산하는 정제 물질이 V. anguillarum 생육에 저해물질로 작용하는 것으로 밝혀졌으며 친환경적인 특성을 가진 물질로 밝혀졌다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 추계학술대회
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• pp.68-68
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• 2019

In this study, we evaluated the effect of Rodgersia podophylla leave extracts (RPL) on ${\beta}$-catenin level in human cancer cells. RPL dose-dependently inhibited cell proliferation in SW480, A549, MDA-MB-231, PC-3 and AsPC-1 cells. RPL dramatically decreased ${\beta}$-catenin protein level in all cancer cells. However, decreased level of ${\beta}$-catenin mRNA expression was observed in A549 and AsPC-1 cells. In addition, RPL dramatically attenuated cyclin D1 mRNA expression in all cancer cells. MG132 decreased the downregulation of ${\beta}$-catenin protein level induced by RPL in all cancer cells, while RPL-induced downregulation of ${\beta}$-catenin was inhibited by the inhibition of $GSK-3{\beta}$ by LiCl in MDA-MB-231 cells. RPL phosphorylated ${\beta}$-catenin and $GSK-3{\beta}$. In addition, the inhibition of $GSK-3{\beta}$ by LiCl attenuated RPL-induced ${\beta}$-catenin phosphorylation. Based on these findings, RPL may be a potential candidate for the development of chemopreventive or therapeutic agents for human cancer.

• The Korean Journal of Physiology
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• 제30권2호
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• pp.279-288
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• 1996

Chronic exposure to cadmium impairs various renal tubular functions, including organic acid (anion) secretion. To investigate the mechanism of cadmium-induced alterations in the organic anion transport system, kinetics of p-aminohippurate (PAH) uptake was studied in renal cortical basolateral membrane vesicles (BLMV) isolated from cadmium-intoxicated rats (adult male Sprague-Dawley). Cadmium intoxication was induced by subcutaneous injections of $CdCl_{2}$ (2 mg Cd/kg per day) for 3 weeks. The renal plasma membrane vesicles were prepared by Percoll gradient centrifugation. The vesicular uptake of $^{14}C$-PAH was determined by rapid filtration technique using Millipore filter. Cadmium intoxication resulted in a marked attenuation of $Na^{+}$-dependent, ${\alpha}$-ketoglutarate (${\alpha}$KG)-driven PAH uptake with no changes in $Na^{+}$ and ${\alpha}$KG-independent transport component. Kinetic analysis indicated that Vmax, but not Km, of the $Na^{+}$-dependent, ${\alpha}$KG-driven component was reduced. A similar reduction of $Na^{+}$-dependent, ${\alpha}$KG-driven PAH uptake was observed in normal membrane vesicles directly exposed to inorganic cadmium in vitro, and this was accompanied by an inhibition of both $Na^{+}$-dependent ${\alpha}$KG uptake and ${\alpha}$KG-PAH exchange activity. These results indicate that during chronic exposure to cadmium, free cadmium ions liberated in the proximal tubular cytoplasm directly interact with the basolateral membrane and impair the active transport capacity for organic anions, most likely due to an inhibition of both $Na^{+}$-dicarboxylate cotransporter and dicarboxylate-organic anion antiporter activities.

• 한국식품과학회지
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• 제24권4호
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• pp.330-334
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• 1992

아미노산 간장의 풍미를 높이기 위해 S. rouxii에 의한 알코올 발효시 아미노산 간장내에 존재하는 NaCl, 색소물질 및 glucose의 농도가 S. rouxii의 생육에 미치는 영향과, 발효온도, 통기속도 등 발효환경요인이 S. rouxii의 생육 및 알코올 발효에 미치는 영향을 관찰하였다. 아미노산 간장내 NaCl 6%(w/v) 까지는 균체 생육에 영향을 미치지 않았으나, 그 이상의 농도에서는 생육을 저해하였으며, 아미노산 간장 중 존재하는 색소물질은 균체 생육에 영향을 미치지 않는 것으로 밝혀졌다. 또 아미노산 간장에 첨가된 glucose의 농도가 25%(w/v)까지는 균체 생육을 크게 저해하지 않았다. S. rouxii의 생육 및 알코올 발효의 최적 온도는 $25^{\circ}C$이며, 최대 알코올 생산을 위한 최적 통기속도는 0.5 vvm이었다. 이때 아미노산 간장내 최대 알코올 농도는 4.2%(w/v)였다.

• BMB Reports
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• 제38권4호
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• pp.481-485
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• 2005

The response of Spirulina (Arthrospira) platensis to high salt stress was investigated by incubating the cells in light of moderate intensity in the presence of 0.8 M NaCl. NaCl caused a decrease in photosystem II (PSII) mediated oxygen evolution activity and increase in photosystem I (PSI) activity and the amount of P700. Similarly maximal efficiency of PSII (Fv/Fm) and variable fluorescence (Fv/Fo) were also declined in salt-stressed cells. Western blot analysis reveal that the inhibition in PSII activity is due to a 40% loss of a thylakoid membrane protein, known as D1, which is located in PSII reaction center. NaCl treatment of cells also resulted in the alterations of other thylakoid membrane proteins: most prominently, a dramatic diminishment of the 47-kDa chlorophyll protein (CP) and 94-kDa protein, and accumulation of a 17-kDa protein band were observed in SDS-PAGE. The changes in 47-kDa and 94-kDa proteins lead to the decreased energy transfer from light harvesting antenna to PSII, which was accompanied by alterations in the chlorophyll fluorescence emission spectra of whole cells and isolated thylakoids. Therefore we conclude that salt stress has various effects on photosynthetic electron transport activities due to the marked alterations in the composition of thylakoid membrane proteins.

• 한국식품조리과학회지
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• 제9권3호
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• pp.215-221
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• 1993

Bioactivity of the extract from various processed garlic was evaluated based on the inhibition of lipoxygenase(LPO), and the effect of some stabilizers on the bioactivity was investigated. Water, ethanol or chloroform extract of 30 min boiled garlic showed 75%, 76% or 70% inhibition, respectively, compared to extracts of fresh garlic. In pickled garlic, LPO inhibition decreased gradually during storage. Chloroform extract of 40 day-stored pickled garlic inhibited LPO by 77%, and even on 60th day storage it still retained inhibitory effect of 73%, compared to that of fresh garlic. Meanwhile, the powdered (freeze-dried) garlic showed more bioactivity(80%) than the other processed garlics, and moreover, the jrreversible/unstable components seem to be stabilized by freeze-drying. The optimum pH for stabilization of bioactive components in garlic macerate was pH 3 for 48 hr incubation and pH 11 for 6 hr incubation. In addition, the effect of NaCl was not so great, although but maximal stabilization was observed at 150 mM. Stabilizing effect of $\alpha$-tocopherol was markedly great, and at 6mM it showed 308% stabilizing effect after 48hr incubation. More stabilizing effect was observed at lower concentrations of ascorbic acid($\leq$0.6mM) than higher concentrations. The stabilizing effect of soybean oil was found to be remarkable only during initial period(6 hr) of incubation.