• 한국환경과학회지
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• 제9권1호
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• pp.43-47
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• 2000

A study on the remediation of heavily for ion contaminated soils from abandoned iron mine was carried out, using ex-situ extraction process. Also, oxalic acid as a complex agent was evaluated as a function of concentration, reaction time and mixing ratio of washing agent in order to evaluate Fe removability of the soil contaminated from the abandoned iron mine. Oxalic acid showed a better extraction performance than 0.1N-HCl, i.e., the concentrations of Fe ion extracted from the abandoned mine for the former at uncontrolled pH and the latter were 1,750 ppm and 1,079 ppm, respectively. The optimum washing condition of oxalic acid was in the ratio of 1:5 and 1:10 between soil and acid solution during l hr reaction. The total concentrations of Fe ion by oxalic acid and EDTA at three repeated extraction, were 4,554 ppm and 864 ppm, respectively. The recovery of Fe ions from washing solution was achieved, forming hydroxide precipitation and metal sulfide under excess of calcium hydroxide and sodium sulfide. In addition, the amounted of sodium sulfide and calcium hydroxide for the optimal revovery of Fe were 15g/$\ell$ and 5g/$\ell$ from the oxalic acid complexes, respectively.

• 에너지공학
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• 제27권1호
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• pp.76-80
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• 2018

The objective of this research paper is to discuss the waste coffee residue disposal and its environmental effects on the environment. As we know, coffee is one of the most demand and swallowed beverages in the world, which leads to large quantities of solid waste. Which can be toxic and a lot of environmental problems occur. In developing countries, there is a lack of proper coffee waste residue management. The coffee beans and residues contain several organic compounds. The wastewater from coffee industry emitted several pollutants (highly concentrated) and it contaminates the soil, ground waters, aquatic life, and also human health. Hence it is essential to treat the coffee waste residues. Mean while, oyster shell waste and its disposal also a big environmental challenge in the coastal regions of southeast Korea. In this paper, we focused the treatment of coffee waste residue with oyster shell waste powder. Primarily, oyster shells are calcinated at higher temperatures and investigated the calcined CaO powder as an anti microbic agent to the bacteria presented in coffee waste residues. We successfully applied calcium oxide from oyster shell waste, as an antimicrobic agent.

• The Korean Journal of Physiology and Pharmacology
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• 제25권3호
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• pp.227-237
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• 2021

Carbon monoxide (CO) is a cardioprotectant and potential cardiovascular therapeutic agent. Human cardiac fibroblasts (HCFs) are important determinants of myocardial structure and function. Large-conductance Ca2+-activated K+ (BK) channel is a potential therapeutic target for cardiovascular disease. We investigated whether CO modulates BK channels and the signaling pathways in HCFs using whole-cell mode patch-clamp recordings. CO-releasing molecules (CORMs; CORM-2 and CORM-3) significantly increased the amplitudes of BK currents (IBK). The CO-induced stimulating effects on IBK were blocked by pre-treatment with specific nitric oxide synthase (NOS) blockers (L-NG-monomethyl arginine citrate and L-NG-nitroarginine methyl ester). 8-bromo-cyclic GMP increased IBK. KT5823 (inhibits PKG) or ODQ (inhibits soluble guanylate cyclase) blocked the CO-stimulating effect on IBK. Moreover, 8-bromo-cyclic AMP also increased IBK, and pre-treatment with KT5720 (inhibits PKA) or SQ22536 (inhibits adenylate cyclase) blocked the CO effect. Pre-treatment with N-ethylmaleimide (a thiol-alkylating reagent) also blocked the CO effect on IBK, and DL-dithiothreitol (a reducing agent) reversed the CO effect. These data suggest that CO activates IBK through NO via the NOS and through the PKG, PKA, and S-nitrosylation pathways.

• Bulletin of the Korean Chemical Society
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• 제32권7호
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• pp.2274-2278
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• 2011

Verapamil is a calcium channel blocker and is classified as a class IV anti-arrhythmic agent. It is used in the control of supra ventricular tachyarrhythmias, and in the management of classical and variant angina pectoris. It is also used in the treatment of hypertension and used as an important therapeutic agent for angina pectoris, ischemic heart disease, hypertension and hypertrophic cardiomyopathy. Verapamil commonly co-administered with NSAIDs (non-steroidal anti-inflammatory drugs) i.e. diclofenac sodium, flurbiprofen, Ibuprofen, mefanamic acid and meloxicam. A simple and rapid RP-HPLC method for simultaneous determination and quantification of verapamil and NSAIDs was developed and validated. The mobile phase constituted of acetonitrile: water (55:45) whose pH was adjusted at 2.7 and pumped at a flow rate of 2.0 mL $min^{-1}$ at 230 nm. The proposed method is simple, precise, accurate, low cost and least time consuming for the simultaneous determination of verapamil and NSAIDs which can be effectively applied for the analysis of human serum.

• 한국식품과학회지
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• 제41권6호
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• pp.657-661
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• 2009

해조칼슘을 습식분쇄한 초미세액상칼슘을 분무건조하여 부형제 종류에 따른 분말칼슘의 품질특성을 알아보고자 gum arabic, cyclodextrin, Na-caseinate를 첨가하여 품질특성을 비교하였다. 분무건조한 초미세분말칼슘의 수분함량은 2% 내외의 안정한 분말을 얻을 수 있었고, 색도는 원료인 해조칼슘보다 L값은 높았으며, b값은 감소하는 것으로 나타났다. 입자크기는 당류의 부형제 첨가로 초미세 크기로 분쇄되는 것을 확인할 수 있었으며, gum arabic을 첨가하여 제조한 초미세액상칼슘을 분무건조한 분말이 식초와 pH에 대한 용해도에서 가장 우수한 것으로 나타났다. 칼슘함량은 해조칼슘분말이 28%의 칼슘함량을 나타내었고, 부형제를 달리하여 제조한 초미세액상칼슘을 분무건조한 분말은 27% 내외로 비슷한 칼슘함량을 나타내어, 습식분쇄나 분무건조 공정에서 칼슘의 손실은 없는 것으로 나타났다. 흡습에 대한 안정성실험에서는 해조칼슘분말이 흡습에 안정하였으며, gum arabic을 첨가하여 분무건조한 분말이 흡습이 많이 발생하였다. 전자주사 현미경 관찰을 통하여 습식분쇄로 입자크기가 작아지는 것을 확인할 수 있었고, gum arabic을 사용하여 얻은 초미세칼슘분말이 단백질계나 사용하지 않았을 때보다 더 균일한 입자분포를 보였다. 따라서 습식분쇄한 초미세액상칼슘을 분말화하여 용해성등 품질특성이 개선됨을 확인하였으며 습식분쇄기술과 분무건조법을 식품가공기술로 활용할 수 있는 가능성을 확보하였다.

• KSBB Journal
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• 제30권2호
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• pp.58-62
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• 2015

본 연구에서는 산란계의 in vivo실험을 통하여 난황 레시틴추출 부산물이 산란계의 뼈의 Ca 침착과 성장에 도움을 줄 수 있다는 결과를 얻었다. 산란계 전기 사료에 Ca의 수준을 0%, 0.2%, 0.4%, 0.6%로 조절하여 실험한 결과 증체량에서 0%, 0.2% Ca을 첨가한 그룹의 증체량은 유의적으로 감소하였으나 0.4%, 0.6% 첨가 그룹에서는 정상적인 성장율을 확인하였다. 반면에 0.4% Ca을 첨가한 그룹에 레시틴 추출 부산물을 0.2%, 0.4% 첨가한 그룹에서 각각 1.5%, 7.1%로 증가하여 농도의존적으로 증가하는 경향을 보였으나 유의한 차이는 없었다. 실제 산란계의 경골을 적출하여 중량, 회분, Ca의 함량을 조사한 결과 경골 중량에서는 0.4% Ca 첨가그룹에 비해 레시틴 추출 부산물을 추가로 첨가한 그룹에서 각각 8.4%, 13.4%로 증가하는 경향을 확인하였다. 회분량에서도 0.4% 첨가 그룹에 비해 레시틴 추출 부산물 첨가그룹에서 증가하였지만, 유의한 차이는 없었다. 경골내의 Ca 함량을 조사한 결과는 0.4% Ca 첨가그룹에 비해 레시틴 추출 부산물이 4.3%, 5.9%가 각각 유의한 경향으로 증가하였다. 경골에 실제로 Ca이 흡수되었는가를 확인하기 위하여 lateral femoral joint 부분을 von Kossa's stain을 실행한 결과 Ca 결핍 그룹에서 Ca 축적이 현저히 감소한 것을 확인한 반면, 그 외 그룹에서는 Ca이 충분히 침착되어 있었으며 산란계 사료내의 적정 Ca 함량이 0.4%라는 것을 다시 한번 확인하였다. 본 연구에서는 계란 난황의 레시틴 추출 부산물의 단백질 분획 소재를 이용하여 뼈 성장 촉진 인자 및 Ca 흡수촉진 보조제로서의 가능성을 보여줬으며, 그 기대를 높이기 위해 혈액분석, 측정항목의 세분화 등 반복적인 연구가 수반되어야 하겠다.

• Journal of Microbiology and Biotechnology
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• 제22권11호
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• pp.1568-1574
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• 2012

Microbiological calcium carbonate precipitation (MCCP) has been investigated for its ability to improve the durability of cement mortar. However, very few strains have been applied to crack remediation and strengthening of cementitious materials. In this study, we report the biodeposition of Bacillus subtilis 168 and its ability to enhance the durability of cement material. B. subtilis 168 was applied to the surface of cement specimens. The results showed a new layer of deposited organic-inorganic composites on the surface of the cement paste. In addition, the water permeability of the cement paste treated with B. subtilis 168 was lower than that of non-treated specimens. Furthermore, artificial cracks in the cement paste were completely remediated by the biodeposition of B. subtilis 168. The compressive strength of cement mortar treated with B. subtilis 168 increased by about 19.5% when compared with samples completed with only B4 medium. Taken together, these findings suggest that the biodeposition of B. subtilis 168 could be used as a sealing and coating agent to improve the strength and water resistance of concrete. This is the first paper to report the application of Bacillus subtilis 168 for its ability to improve the durability of cement mortar through calcium carbonate precipitation.

• Molecules and Cells
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• 제44권10호
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• pp.758-769
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• 2021

Calcium homeostasis modulator 1 (CALHM1) is a membrane protein with four transmembrane helices that form an octameric ion channel with voltage-dependent activation. There are four conserved cysteine (Cys) residues in the extracellular domain that form two intramolecular disulfide bonds. We investigated the roles of C42-C127 and C44-C161 in human CALHM1 channel biogenesis and the ionic current (I_CALHM1). Replacing Cys with Ser or Ala abolished the membrane trafficking as well as I_CALHM1. Immunoblotting analysis revealed dithiothreitol-sensitive multimeric CALHM1, which was markedly reduced in C44S and C161S, but preserved in C42S and C127S. The mixed expression of C42S and wild-type did not show a dominant-negative effect. While the heteromeric assembly of CALHM1 and CALHM3 formed active ion channels, the co-expression of C42S and CALHM3 did not produce functional channels. Despite the critical structural role of the extracellular cysteine residues, a treatment with the membrane-impermeable reducing agent tris(2-carboxyethyl) phosphine (TCEP, 2 mM) did not affect I_CALHM1 for up to 30 min. Interestingly, incubation with TCEP (2 mM) for 2-6 h reduced both I_CALHM1 and the surface expression of CALHM1 in a time-dependent manner. We propose that the intramolecular disulfide bonds are essential for folding, oligomerization, trafficking and maintenance of CALHM1 in the plasma membrane, but dispensable for the voltage-dependent activation once expressed on the plasma membrane.

• 한국도로학회논문집
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• 제7권3호
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• pp.53-62
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• 2005

겨울철 원활한 제설작업은 겨울철 도로운영 및 관리에 중요한 공정이다. 현재 우리나라에서는 염화칼슘을 제설제로 가장 많이 쓰고 있고, 성능은 우수하지만 환경문제와 부식으로 인한 도로주변의 콘크리트 구조물의 내구성을 저하시키는 원인이 되고 있어 심각한 문제가 되고 있다. 한편 유기성 폐기물을 이용하여 환경친화 제설제인 Ca, Mg와 유기산(초산, 프로피온산)의 반응물인 유기산염 (CMO, Calcium magnesium salt of organic acids)으로 구성된 제설제의 경우 자원 재활용으로 인한 생산 단가를 낮출 수 있고 환경문제와 구조물의 내구성저하를 해결할 수 있다는 연구들이 수행된 바 있다. 본 연구에서는 실험실에서 화학조성에 의해 샘플로 제조된 환경친화 제설제인 유기산염(CMO의 일종)과 미국에서 개발한 CMA, 기존 제설제에 대해 제설에 필요한 기초물성에 대한 실험과 성능 실험을 통해 융빙성능을 비교 분석하였고 콘크리트 표면의 중량 손실량 실험을 통하여 구조물의 내구성에 미치는 영향을 검토하였다. 결과 분석을 통해 CMO의 융빙성능은 기존 제설제인 염화칼슘에 비해 60$\sim$90% 정도의 효과를 보였다. 중량손실효과는 미미하여 구조물의 내구성에 영향을 거의 미치지 않음을 알 수 있었다.

• Journal of Veterinary Science
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• 제24권6호
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• pp.74.1-74.15
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• 2023

Background: Antibiotic beads are used to treat local bacterial infections by delivering high drug concentrations to infected tissue. Objectives: This study examined the elution characteristics of metronidazole from metronidazole-calcium sulfate (MCa) and metronidazole-calcium-potassium sulfate (MCaK) beads over 20 days and the antibacterial efficacy of the beads after storage. Methods: The MCa and MCaK beads were prepared by mixing 250 mg of metronidazole and 10 g of calcium sulfate hemihydrate with water and a 3% potassium sulfate solution, respectively. The beads were placed in phosphate-buffered saline for the elution study. The metronidazole eluents were determined using high-performance liquid chromatography. The microstructures were examined by scanning electron microscopy (SEM), and the antimicrobial activity was evaluated by a microbioassay. Results: For the 20-day study, the total amount of metronidazole released was greater in the MCa beads than in the MCaK beads by 6.61 ± 0.48 mg (89.11% ± 3.04%) and 4.65 ± 0.36 mg (73.11% ± 4.38%), respectively. The amounts of eluted drugs from the MCa and MCaK beads were higher than the minimum inhibitory concentration at 0.5 ㎍/mL against anaerobic bacteria at both 20 days and 14 days. SEM showed that calcium crystals on the outer surface had dissolved after elution, and thinner calcium crystals were prominent in the MCaK beads. The MCa and MCaK beads exhibited antibacterial activity after setting, followed by storage at room temperature or 4℃ for 21 days. Conclusions: The MCa beads could release more drug than the MCaK beads, but all eluted metronidazole amounts were effective in controlling bacterial infections. Both metronidazole beads could be stored at ambient temperature or in a refrigerator.