• Korean Journal of Agricultural Science
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• v.14 no.1
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• pp.144-155
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• 1987

A potent fungus producing milk clotting enzyme with fairly weak proteolytic activity was isolated from various soil and sewage, which the selected strain, SA-101, was identified as Mucor sp. with microbiological characteristics. Its milk clotting enzyme production was maximized when grown on 10g of wheat bran media added to 8ml of tap water containing 0.1M HCl for 60hrs at $30^{\circ}C$. This enzyme production was stimulated by addition of 6% lactose, 0.05% NaCl and reached a maximal level of 9810 unit/g wheat bran. The crude enzyme product could be produced effectively by salting out with ammonium sulfate fractionation and lyophilization. The ratio of milk clotting activity to proteolytic activity of crude enzyme product was lower than Hansen rennet, but resembled to Meito rennet. The optimal temperature of milk clotting activity of crude enzyme product was abound $60^{\circ}C$ on a substrate of 10% reconstituted skim milk containing 1/100M $CaCl_2$.

• Journal of Veterinary Science
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• v.23 no.3
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• pp.48.1-48.12
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• 2022

Background: The poor intracellular concentration of enrofloxacin might lead to treatment failure of cow mastitis caused by Staphylococcus aureus small colony variants (SASCVs). Objectives: In this study, enrofloxacin composite nanogels were developed to increase the intracellular therapeutic drug concentrations and enhance the efficacy of enrofloxacin against cow mastitis caused by intracellular SASCVs. Methods: Enrofloxacin composite nanogels were formulated by an electrostatic interaction between gelatin (positive charge) and sodium alginate (SA; negative charge) with the help of CaCl₂ (ionic crosslinkers) and optimized by a single factor test using the particle diameter, zeta potential (ZP), polydispersity index (PDI), loading capacity (LC), and encapsulation efficiency (EE) as indexes. The formation mechanism, structural characteristics, bioadhesion ability, cellular uptake, and the antibacterial activity of the enrofloxacin composite nanogels against intracellular SASCVs strain were studied systematically. Results: The optimized formulation was comprised of 10 mg/mL (gelatin), 5 mg/mL (SA), and 0.25 mg/mL (CaCl₂). The size, LC, EE, PDI, and ZP of the optimized enrofloxacin composite nanogels were 323.2 ± 4.3 nm, 15.4% ± 0.2%, 69.6% ± 1.3%, 0.11 ± 0.02, and -34.4 ± 0.8 mV, respectively. Transmission electron microscopy showed that the enrofloxacin composite nanogels were spherical with a smooth surface and good particle size distributions. In addition, the enrofloxacin composite nanogels could enhance the bioadhesion capacity of enrofloxacin for the SASCVs strain by adhesive studies. The minimum inhibitory concentration, minimum bactericidal concentration, minimum biofilm inhibitory concentration, and minimum biofilm eradication concentration were 2, 4, 4, and 8 ㎍/mL, respectively. The killing rate curve had a concentration-dependent bactericidal effect as increasing drug concentrations induced swifter and more radical killing effects. Conclusions: This study provides a good tendency for developing enrofloxacin composite nanogels for treating cow mastitis caused by intracellular SASCVs and other intracellular bacterial infections.

• Applied Chemistry for Engineering
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• v.19 no.1
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• pp.111-116
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• 2008

Collapsed perflurostearic acid (PFS) films were prepared on the different pH and the various metal ion ($Na^+$, $Ca^{2+}$, $La^{3+}$) containing subphase using Langmuir-Blodgett (LB) trough. The degree of ionization of collapsed PFS film formed from floating monolayer has been determined by Fourier transform infrared (FTIR) spectroscopy. The intensity of C = O of -COOH peaks of collapsed PFS decreased with increasing pH of subphase. The order of ionization of collapsed PFS on the subphase of the same pH was $La^{3+}$ > $Ca^{2+}$ > $Na^+$. The degree of ionization of collapsed PFS on the Deionized (D.I.) water subphase is above 50% even at subpahse pH 3, which is much higher degree of ionization than that of stearic acid.

• The Journal of the Petrological Society of Korea
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• v.9 no.2
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• pp.84-98
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• 2000

Daejeon-sa basalt in the Mt. Juwang area composed of 12 basalt flows alternate with 9 peperites and each basalt and peperite has the variety of thickness. Peperites yielded in Daejeon-sa basalt are mixed of basalt with reddish shale, of which textural type is globular peperite. Basalts yielded in Daejeon-sa basalt are massive basalt without vesicule, although sometimes vesicules are founded in upper within a flow unit. The basalt has mainly pseudomorph of olivine as phenocryst, and also plagioclase and clinopyroxene phenocryst. Matrix is mainly subophitic texture. The plotting result on the TAS diagram shows these basalts belong to the sub-alkaline, and it can be subdivided into calc-alkaline series on the basis of the diagram of Si02 vs. K20 and of alkali index vs. A1203 diagram. According to plots of wt.% oxides vs. wt.% MgO, abundances of A1203 and CaO increase with decreasing MgO while F ~ dOecre~ase . With decreasing MgO compatible elements decrease while incompatible elements increase. In spider diagram of MORB-normalized trace element patterns, HFS elements are nearly similiar with MORB, but LIL elements are enriched. Especially, contents of Ce, F: and Sm are enriched but Nb is depleted. In the chondrite-normalized REE patterns light REEs are enriched than heavy REEs. Tectomagmatic discrimination diagrams shows basalts in the study area are formed in the tectonomagmatic environment of subduction zone under continental margin. This result accord with characters of chemical composition mentioned above. Cr vs. Y diagram and CeM, vs. Ce diagram show that the primary magma of the basalts may formed by the about 15% partial melting of garnet-peridotite in the mantle wedge. After then, Daejeon-sa basalts may formed from evolved magma undergone mainly olivine fractional crystallization and contarnination of crustal materials before eruption.

• BMB Reports
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• v.41 no.2
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• pp.112-118
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• 2008

Camptothecin is an anti-cancer monoterpene indole alkaloid. The gene encoding 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase (designated as CaHDR), the last catalytic enzyme of the MEP pathway for terpenoid biosynthesis, was isolated from camptothecin-producing Camptotheca acuminata. The full-length cDNA of CaHDR was 1686 bp encoding 459 amino acids. Comparison of the cDNA and genomic DNA of CaHDR revealed that there was no intron in genomic CaHDR. Southern blot analysis indicated that CaHDR belonged to a low-copy gene family. RT-PCR analysis revealed that CaHDR expressed constitutively in all tested plant organs with the highest expression level in flowers, and the expression of CaHDR could be induced by 100 ${\mu}M$ methyl-jasmonate (MeJA), but not by 100 mg/L salicylic acid (SA) in the callus of C. acuminata. The complementation of CaHDR in Escherichia coli ispH mutant MG1655 demonstrated its function.

• Applied Chemistry for Engineering
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• v.30 no.5
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• pp.562-568
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• 2019

Cylindrical shape extrudates of calcium silicate hydrate (CSH) were prepared using different percentages of polyvinyl alcohol (PVA) / sodium alginate (SA) mixtures as binders and an aqueous solution containing 6% $H_3BO_3$ and 3% $CaCl_2$ was used as a cross linking agent. As the quantity of alginate increases, the phosphate removal efficiency and capacity were decreased. Among four different extrudate samples, the sample prepared by 8% PVA + 2% SA showed the highest phosphate removal efficiency (59.59%) and capacity (29.97 mg/g) at an initial phosphate concentration of 100 ppm and 2.0 g/L adsorbent dosage. Effects of the adsorbent dosage, contact time and initial phosphate concentration on the sample were further studied. The removal efficiency and capacity obtained by a 4.0 g/L adsorbent dose at an initial phosphate concentration of 100 ppm in 3 h were 79.38% and 19.96 mg/g, respectively. The experimental data of kinetic and isotherm measurements followed the pseudo-second-order kinetic equation and Langmuir isotherm model, respectively. These results suggested that the phosphate removal was processed via a chemisorption and a monolayer coverage of phosphate anions was on the CSH surface. The maximum adsorption capacity ($q_{max}$) was calculated as 23.87 mg/g from Langmuir isotherm model.

• The Korean Journal of Pharmacology
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• v.8 no.1
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• pp.67-75
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• 1972

Many studies on the mechanism of the inotropic action of cardiac glycosides have shown the possible intimate relationship between the mobilization of intracellular calcium and inotropic effect. Evidence obtained from recent studies suggests that cardiac glycosides may increase the intracellular $Ca^{++}$ concentration through the release of this ion from cellular or intracellular membrane. It seemed imperative to study the effect of ouabain on the interaction between mitochondria and $Ca^{++}$, because mitochondria are known to have a rather powerful $Ca^{++}$ pump mechanism which may have an important role on the regulation of intracellular $Ca^{++}$ concentration. The present investigations was made into the effect of ouabain on $Ca^{++}$ untake of mitochondria in the presence of ATP and its dependence on $K^+$ and $Na^+$ in the medium. The results are summarized as follows: 1. The rate of rise in the turbidity of superprecipitation was solely influenced by ionic strength of the medium, not by the species of ion, i.e. $Na^+$ or $K^+$. The higher ionic strength suppressed and the lower enhanced the rate of superprecipitation respectively. 2. No effect of ouabain was found on the rate of superprecipitation. 3. Mitochondria depressed the rate of superpretipitation, and the depressed rate of superprecipitation by mitochondria was reversed by ouabain, and the degree of this reversal was almost identical in $Na^+$ and $K^+$ medium. 4. $Ca^{++}$ uptake of mitochondria was inhibited by ouabain in the presence of ATP and the degree of inhibition showed the dose-response manner in terms of concentration of ouabain. 5. In the absence of ATP, mitochondria took or the $Ca^{++}$ in initial period but released it later. Such uptake and release of $Ca^{++}$ was not influenced by ouabain. 6. It is suggested that intracellular calcium mobilization by ouabain through the action upon the mitochondria was due to inhibition on ATP-dependent $Ca^{++}$ uptake by this agent, not to the action upon so called binding.

• The Korean Journal of Physiology
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• v.19 no.2
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• pp.101-111
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• 1985

Transient inward current (TI) was studied by the two micro-electrode voltage clamp technique in the sinoatrial node of the rabbit. The author confirmed that in $10^{-6}$ M ouabain TI was found in the SA node and investigated the effects of ions, $(Na^+,\;K^+,\;Ca^{2+})$, $\beta-agonist$ (isoprenaline), local anesthetics (quinidine, lidocaine) and Ca-blockers ($Co^{2+}$, verapamil, diltiazem) on the TI recorded during depolarizing voltage clamp pulses to -40 and -20 mV. The results obtained were as follows ; 1) $10^{-6}M$ ouabain increased the frequency of sinus action potential and decreased the amplitude, especially overshoot of action potential. TI was induced by the depolarizing voltage clamp Pulses and the magnitude of the slow inward current (isi) decreased and the time course was slowed by the same depolarizing pulses. 2) 30% $Na^{+}$ and 24mM $K^+$ decreased by $10^{-6}M$ ouabain and 6 mM $Ca^{2+}$ and $10^{-7}M$ isoprenaline increased TI, $i_{si}$ and current oscillations. 3) Quinidine $(5\times10^{-7}M)$ reduced TI and $i_{si}$ but lidocaine $(10^6\;-10^5M)$ didn't reduced or increase TI. Current oscillations increased and isi decreased by lidocaine. 4) Ca-blockers decreased the amplitude and the frequency of sinus action potential. TI and $i_{si}$ decreased significantly but were not abolished completely at the concentrations used in this experiment. Verapamil and diltiazem had inhibitory action on TI in $2\times10^{-7}M$ concentration and showed very slow recovery after wasting out with normal Tyrode solution.

• Korean Journal of Acupuncture
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• v.38 no.3
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• pp.162-174
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• 2021

Objectives : We aimed to identify the antidepressant effect of liver tonification acupuncture treatment (ACU (LT); KI10, LR8, LU8, LR4) and four gate acupuncture treatment (ACU (FG); LI4, LR3) and its brain neural activity in the normal and chronic restraint stress (CRS)-induced mouse model. Methods : Firstly, normal mice were given ACU (LT) or ACU (FG) and the c-Fos expressions in each brain region were analyzed to examine brain neural activity. Secondly, CRS was administered to mice for 4 weeks, then ACU (LT) or ACU (FG) was performed for 2 weeks. The depression-like behavior was evaluated using open field test (OFT) before and after acupuncture treatment. Then, the c-Fos expressions in each brain region were analyzed to examine brain neural activity. Results : In normal mice, ACU (FG) regulated brain neural activities in the hypothalamus, hippocampus, and periaqueductal gray. ACU (LT) changed more brain regions in the prefrontal cortex, insular cortex, striatum, and hippocampus, including those altered by ACU (FG). In CRS-induced model, ACU (LT) alleviated depression-like behavior more than ACU (FG). Also, brain neural activities in the motor cortex area 2 (M2), agranular ventral part and piriform of insular cortex (AIV and Pir), and cornu ammonis (CA) 1 and CA3 of hippocampus were changed by ACU (LT), and those of AIV and CA3 were also changed by ACU (FG). As in normal mice, ACU (LT) resulted in changes in more brain regions, including those altered by ACU (FG) in CRS model. M2, Pir, and CA1 were only changed by ACU (LT) in depression model, suggesting that these brain regions reflect the specific effect of ACU (LT). Conclusions : ACU (LT) relieved depression-like behavior more than ACU (FG), and this acupuncture effect was associated with modulation of brain neural activities in the motor cortex, insular cortex, and hippocampus.

• Journal of Microbiology and Biotechnology
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• v.31 no.1
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• pp.43-50
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• 2021

A newly cloned 4-α-glucanotransferase (αGT) from Deinococcus geothermalis and two typical bacterial αGTs from Thermus scotoductus and Escherichia coli (MalQ) were investigated. Among 4 types of catalysis, the cyclization activity of αGTs that produces cycloamylose (CA), a valuable carbohydrate making inclusion complexes, was intensively studied. The new αGT, DgαGT, showed close protein sequence to the αGT from T. scotoductus (TsαGT). MalQ was clearly separated from the other two αGTs in the phylogenetic and the conserved regions analyses. The reaction velocities of disproportionation, cyclization, coupling, and hydrolysis of three αGTs were determined. Intriguingly, MalQ exhibited more than 100-fold lower cyclization activity than the others. To lesser extent, the disproportionation activity of MalQ was relatively low. DgαGT and TsαGT showed similar kinetics results, but TsαGT had nearly 10-fold lower hydrolysis activity than DgαGT. Due to the very low cyclizing activity of MalQ, DgαGT and TsαGT were selected for further analyses. When amylose was treated with DgαGT or TsαGT, CA with a broad DP range was generated immediately. The DP distribution of CA had a bimodal shape (DP 7 and 27 as peaks) for the both enzymes, but larger DPs of CA quickly decreased in the DgαGT. Cyclomaltopentaose, a rare cyclic sugar, was produced at early reaction stage and accumulated as the reactions went on in the both enzymes, but the increase was more profound in the TsαGT. Taken together, we clearly demonstrated the catalytic differences between αGT groups from thermophilic and pathogenic bacteria that and showed that αGTs play different roles depending on their lifestyle.