• Journal of Korean Society of Environmental Engineers
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• v.37 no.1
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• pp.60-68
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• 2015

The study of waste activated sludge (WAS) solubilization has been increased for sludge volume reduction and enhancing the efficiency of anaerobic digestion. Microwave (MW)-assisted solubilization is an effective method for the solubilization of WAS because this method can lead to thermal, nonthermal effect and ionic conduction by dielectric heating. In this study, the solubilization of WAS by MW heating and conductive heating (CH) was compared and to enhance the MW-assisted solubilization of WAS at low MW output power, chemical agents were applied such as $H_2SO_4$ as the strong acid and $CaCl_2$, NaCl as the ionic materials. Compared to the COD solubilization of WAS by CH, that by MW heating was approximately 1.4, 6.2 times higher at $50^{\circ}C$, $100^{\circ}C$, respectively and the highest COD solubilization of WAS was 10.0% in this study of low MW output power condition. At the same MW output power and reaction time in chemically agents assisted experiments, the COD solubilization of WAS were increased up to 18.1% and 12.7% with the addition of $H_2SO_4$ and NaCl, however, that with the addition of $CaCl_2$ was 10.7%. This result might be due to the fact that the precipitation reaction occurred by calcium ion ($Ca^{2+}$) and phosphate ion (${PO_4}^{3-}$) produced in WAS after MW-assisted solubilization. In this study, $H_2SO_4$ turned out to be the optimal agent for the enhancement of MW efficiency, the addition of 0.2 M $H_2SO_4$ was the most effective condition for MW-assisted WAS solubilization.

• KSBB Journal
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• v.10 no.3
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• pp.343-348
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• 1995

Human lipocorin-I(LCI) is a calcium ion-dependent and phospholipid-binding protein which exhibits an anti-inflammatory activity by inhibiting phospholipase A2 activity. In this study, the LCI gene containing its own terminator region was joined to GAL10 promoter-ppL (prepro-leader sequence of mating factor a). An ATG start codon of LCI gene was placed at downstream with KR endoprotease recognition site(Lys-Arg) of ppL. Recombinant S. cerevisiae harboring the LCI expression/secretion vector, pYGLPT5, was aerobicall grown on a liquid YPDG medium al $30^{\circ}C$ for 72hys. The whole cell and culture supernatant were separated after centrifugation, and the expressed LCI was analyzed by SDS-PAGE and western blotting methods. A majority fraction of the expressed LCI was found to be accumulated in the intracellular fraction, resulting in very low secretion efficiency of about 7.4%. About $500mg/\ell$ of LCI was extracellularly produced by the fed-batch culture employing the controlledfeeding of glucose and galactose. The secreted LCI was purified by ultrafiltration and hydroxylapatite column chromatography, and a purity of more than 99% was obtained.

• Journal of the Korean Chemical Society
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• v.65 no.4
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• pp.249-253
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• 2021

Litter and manure were obtained at a cow house of a livestock farm in Andondg city. We examined the change of formation of nitrogen and phosphorous from these samples and tried to suggest a more useful and realistic way for removing them. Constituent and its content of sample were identified by XRF. NO₂^-, NO₃^-, and PO₄^3- ions and NH₄⁺, T-P and T-N released from sample were analyzed using ion chromatograph and UV/Vis spectrometry, respectively. As the results of this study, the ammonia nitrogen in the early stage of cow excretion is a need to make an ammonia gas state that can be immediately volatile by increasing the pH. Nitrogen and phosphorous, the main source of nutrition in green algal bloom can be removed by transforming insoluble salts such as calcium phosphate (CaHPO₄·3H₂O) and struvite (NH₄MgPO₄·6H₂O), respectively, with addition of Ca and Mg after stimulating fermentation of manure.

• Korean Journal of Food Science and Technology
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• v.22 no.4
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• pp.426-433
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• 1990

The conditions for immobilization of the partially purified ${\beta}-galactosidase$ form Bacillus subtilis HP4 and the properties of the immobilized enzyme have been investigated. The crude enzyme precipitated with cold acetone was purified about 68-fold through DEAE-cellulose and sephadex G-100 chromatography and its recovery was 19.9% The optimal conditions for Immobilization of enzyme were obtained in 2%(w/v) sodium alginate, 15%(v/v) enzyme solution and 2%(w/v) calcium chloride, and also the optimal stirring thme was 2 hours on the above conditions. The optimum temperature and pH values for immobilized enzyme were $55^{\circ}C$ and 6.5, respectively. Its residual activity was show 25% after heat treatment for an hour at $65^{\circ}C$, and found its high stability in pH 6.0 to 8.0. The enzyme activity was not affected b)· EDTA, 2-mercaptoethanol, KCN, protective agents, and other methal ions except Hg ion and Cu ion. The $K_m\;and\;V_{max}$ values of the immobilized enzyme on ONPG were $1.82{\times}10^{-2}M\;and\;3.57{\times}10^{-8}mole/min$, whereas those on lactose were $2.94{\times}10^{-2}M\;and\;1.68{\times}10^{-7} mole/min$, respectively. The remained enzyme activity for the immobilized enzyme was 95%t of original activity after storage of 40 days at $4^{\circ}C$, and when reused for 5 times was 81%. When skim milk(4.8% lactose) and 5% lactose solution were reacted with the immobilized enzyme(250 units/g) of lactose were 51% and 43%, respectively.

• Applied Biological Chemistry
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• v.12
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• pp.75-81
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• 1969

In order to obtain a method of scouring of raw silk and degumming of cocoon by the appling of bacterial enzyme of sericinase, a strain of proper bacteria was isolated and some properties of the enzyme produced by the isolated bacteria were studied and the following results were obtained. 1) Optimum pH and temperature were indicating 7.5 and $50^{\circ}C$. and on these conditions, the silk fibroin will get no modification at all. 2) Sericinase activity was inhibited by calcium ion in the free incubation but same ions reacted as an activator in the reaction with substrate. So, degumming of Tussah cocoon which contains calcium oxalate in the cocoon layer will be possible by the treatment of this enzyme. 3) This bacterial sericinase never gives any affection to the fibroin layer of the silk. 4) The factors of smooth-surface condition, damage of fibroin layer, touching, luster and degumming effect of the silk resulting by the enzyme treatment were more appropriate than the results of other scouring methods, saponin, alkali and saponin-alkali using methods. We expect to get the same scouring result that compared with the papain or pancreatin were applied.

• Polymer(Korea)
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• v.35 no.4
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• pp.363-369
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• 2011

To study the effect of incorporation of a surface crosslinking layer on a crosslinked poly (sodium acrylate) (cPSA) absorbent with ethylene glycol dimethacrylate CEGDMA), we synthesized several surface crosslinked cPSAs with EGDMA by an inverse emulsion polymerization method to delay the absorption of excess water in concrete, Liquid paraffin was used as a continuous phase. cPSA was synthesized with acrylic acid (AA) neutralized with aqueous 8 M sodium hydroxide solution as a monomer, N,N-methylene bisacrylamide (MBA) as crosslinking agent and ammonium persulfate (APS) and sodium metabisulfite (SMBS) as a redox initiator system by inverse emulsion polymerization. FTIR spectroscopy was used to characterize $Ca^{2+}$ ion interaction with cPSA and cPSA-EGDMAs. The swelling ratios of synthesized absorbents were evaluated from the absorption in deionized water, cement saturated aqueous solution and aqueous solution of calcium hydroxide (pH 12). Equilibrium swelling times for cPSA and surface crosslinked cPSA with EGDMA were 2 and 3 hrs, respectively. We also observed an increase in setting time of the cement and an increase in the compressive strength of mortar by addition of the synthesized cPSA-EGDMA.

• BMB Reports
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• v.30 no.2
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• pp.101-105
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• 1997

Extracellular phospholipase $A_2$ activity has been detected in urine of patients with acute pyelonephritis (APN). This enzyme required micromolar $Ca^{2+}$ ion for its maximum activity and showed a broad range of pH (4.5~10) optimum. Urine enzyme hydrolyzed phosphatidylethanolamine (PE) and phosphatidylserine (PS) more effectively than phosphatidylcholine (PC). $PLA_2$ activity in the urine of patients with APN was about 5-fold higher than that of healthy individuals. When urine was subjected to heparinSepharose column chromatography, phospholipase $A_2$ activity was detected in both heparin-non-binding and binding fractions. Both phospholipase $A_2$ activities were sensitive less than a micromolar calcium concentration and did not react with anti-human 14-kDa group II phospholipase $A_2$ monoclonal antibody, HP-l. These findings suggest that two kinds of novel extracellular phospholipase $A_2$. which may not belong to the 14-kDa group II phospholipase $A_2$ family, exist in the urine of patients with APN.

• Journal of Ginseng Research
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• v.32 no.1
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• pp.73-78
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• 2008

Red ginseng acidic polysaccharide (RGAP), isolated from Korean red ginseng (Panax ginseng C.A. Meyer), has been shown to have a variety of biological functions such as immunostimulating and anti-tumor activities. In the present study, we investigated whether RGAP inhibited ligand-induced platelet aggregation. The washed platelet-rich plasma was prepared from male SD rats with successive centrifugation. The platelets $(10^8/ml)$ were preincubated with 1 mM of $CaCl_2$ for 2 min either in the presence or in the absence of RGAP $(10{\sim}50\;{\mu}g/ml)$ and were stimulated with collagen (2.5 ${\mu}g/ml$) and thrombin (0.1 U/ml). RGAP dose-dependently inhibited thrombin-induced platelet aggregation with $IC_{50}$ value of $26.2{\pm}2.0$ ${\mu}g/ml$. In collagen-induced platelet aggregation, RGAP inhibited the reaction with an $IC_{50}$ value of $31.5{\pm}3.0\;{\mu}g/ml$. RGAP potently suppressed the intracellular calcium ion, which was stimulated by thrombin (0.1 U/ ml). Among mitogen-activated protein kinase (MAPK) subtypes, the extracellular signal-regulated kinase (ERK) 1/2 and p38 MAPK were analyzed in the present study. RGAP inhibited the phosphorylation of ERK2 and p38 MAPK, which was activated by collagen (2.5 ${\mu}g/ml$). Finally, these results suggested that besides saponin fraction, RGAP take an important role in the preventive effect of Korean red ginseng against cardiovascular disease such as thrombosis and atherosclerosis.

• Journal of Ginseng Research
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• v.39 no.3
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• pp.279-285
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• 2015

Background: Korean Red Ginseng has been used as a traditional oriental medicine to treat illness and to promote health for several thousand years in Eastern Asia. It is widely accepted that ginseng saponins, ginsenosides, are the major active ingredients responsible for Korean Red Ginseng's therapeutic activity against many kinds of illness. Although the crude saponin fraction (CSF) displayed antiplatelet activity, the molecular mechanism of its action remains to be elucidated. Methods: The platelet aggregation was induced by collagen, the ligand of integrin ${\alpha}_{II}{\beta}_I$ and glycoprotein VI. The crude saponin's effects on granule secretion [e.g., calcium ion mobilization and adenosine triphosphate (ATP) release] were determined. The activation of mitogen-activated protein kinases (MAPKs), including extracellular signal-regulated protein kinase 1/2 (ERK1/2), c-Jun N-terminal kinases (JNKs), and p38 MAPK, and phosphoinositide 3-kinase (PI3K)/Akt was analyzed by immunoblotting. In addition, the activation of integrin ${\alpha}_{II}b{\beta}_{III}$ was examined by fluorocytometry. Results: CSF strongly inhibited collagen-induced platelet aggregation and ATP release in a concentration-dependent manner. It also markedly suppressed $[Ca^{2+}]_i$ mobilization in collagen-stimulated platelets. Immunoblotting assay revealed that CSF significantly suppressed ERK1/2, p38, JNK, PI3K, Akt, and mitogen-activated protein kinase kinase 1/2 phosphorylation. In addition, our fraction strongly inhibited the fibrinogen binding to integrin ${\alpha}_{IIb}{\beta}_3$. Conclusion: Our present data suggest that CSF may have a strong antiplatelet property and it can be considered as a candidate with therapeutic potential for the treatment of cardiovascular disorders involving abnormal platelet function.

• Resources Recycling
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• v.14 no.2
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• pp.10-18
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• 2005

The manufacture property of anhydrous calcium sulfate (anhydrite Ⅱ) from flue gas desulfurization (FGD) gypsum discharged from domestic thermoelectric power plants to apply as an auxiliary material of cement and concrete by high temperature treatment were investigated. The FGD gypsum was completely converted to anhydrite Ⅱ at the temperature of 700$^{\circ}C$ and the retention time of 1 hr. In the phase transformation process, particle size was also changed. The chemical composition, particle size and heat property of anhydrite Ⅱ made from the FGD gypsum were similar to them of natural gypsum. In the leaching test of sulfate ion (SO$_4^{2-}$) at the temperature of 90$^{\circ}C$ and the retention time of 1 hr, the amount of leached SO$_4^{2-}$ for the anhydrite Ⅱ that was sintered at 700$^{\circ}C$ for 1 hr was about 50 wt.% based on that of natural gypsum. In addition, the amount of leached SO$_4^{2-}$ for the anhydrite Ⅱ by adding the slaked lime of 3 wt.% decreased about 70 wt.% comparing with that of natural gypsum. In the application test, the compressive strength of cement and concrete manufactured by using the anhydrite Ⅱ as an auxiliary material were similar or superior compared with them of cement and concrete done by natural gypsum as an auxiliary material.