• Microbiology and Biotechnology Letters
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• v.32 no.3
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• pp.224-229
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• 2004

Several microorganisms (esterase-producing group) were isolated by the solid selective media containing-naphtylacetate. Among them, strain 366M-9 having a high activity of cephalosporin-C deacetylase (CAH; EC 3.1.1.41) was selected. The strain 366M-9 was identified as Bacillus sphaericus on the basis of morphological, physiological, and biochemical characteristics. The production of CAH reached at maximum value after 32 hrs, when cultivated in the optimal medium containing dextrin 2.5%, peptone 2.5%, sodium chloride 0.5%, dipotassium phosphate 0.25%, ferrous sulfate 0.02%, and 7-ACA 0.1% at $30^{\circ}C$ with initial pH 6.0. The CAH was purified by 3 steps with ammonium sulfate precipitation, adsorption chromatography on hydroxyapatite column, and Sephadex G-200 gel chromatography. The final enzyme preparation was homogeneous as judged by the analysis of SDS-PAGE and HPLC. Optimum temperature and pH for CAH activity were $50{\circ}C$ and around 7.0, respectively. And the enzyme was stable at pH 6.0～8.0, up to $50^{\circ}C$. The Michaelis-Menten constants ($K_{m}$ ), $V_{max}$ were 0.87 mM and 1.22 unit/ml, respectively.

• Environmental Engineering Research
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• v.20 no.3
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• pp.246-253
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• 2015

The effects of carbon-to-nitrogen (C/N) ratio in simulated rice straw hydrolysates using glucose and ammonium chloride on polyhydroxyalkanoates (PHA) accumulation by Cupriavidus necator was investigated. In general, PHA accumulation rate was higher under higher degrees of N-deficient conditions (e.g., C/N ratio of 360:1) than lower degrees of N-deficient conditions (e.g., C/N ratio of 3.6:1 and 36:1). Also, the most PHA accumulation was observed during the first 12 h after the PHA accumulation initiation. This study showed that the similar PHA accumulation could be achieved by using different accumulation periods depending on C/N ratios. N source presence was important for new cell production, supported by approximately ten times greater PHA accumulation under the N-deficient condition ($NH_4Cl$ 0.01 g/L) than the N-free (without $NH_4Cl$) condition after 96 h. C/N ratio of the rice straw hydrolysate was approximately 160:1, based on the glucose content, and this accumulated $0.36{\pm}0.0033g/L$ PHA with PHA content of $21{\pm}3.1%$ after 12 h. Since external C or N source addition for C/N ratio adjustment increases production cost, an appropriate accumulation period may be used for PHA accumulation from organic wastes, based on the PHA accumulation patterns observed at various C/N ratios and C and N concentrations.

• Applied Biological Chemistry
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• v.23 no.1
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• pp.14-22
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• 1980

White and black sesame produced in Korea were defatted with ethyl ether or n-hexane. Defatted sesame meal was extracted with water and salt solution, and protein extraction was precipitated at various pH 1 through 12, with trichloro acetic acid (TCA), tannic acid and ammonium sulfate, respectively. Protein was purified by Sephadex A-25, G-75, G-100 and G-200, and identified its protein fraction by polyacrylamide gel electrophoresis. Amino acids composition of protein in white sesame was analyzed by automatic amino acid analyzer. Protein contents of white sesame, black sesame and sesame meal are 20.5%, 19.2%, and 44.7%, respectively. n-Hexane was the most suitable solvent for extraction of oil from sesame. Crude protein precipitation was better in higher pH. The protein extraction was more effective with the solution containing sodium chloride tinder the pH 8. Globulin in total protein was high and prolamin was less than in other cereal proteins. Glutamic acid contents of white sesame and sesame globulin were 17.1%, and 20%, respectively. Both proteins contained relatively high levels of essential amino acids. 12-13 bands were found in water soluble protein and 2 bands in salt soluble protein were detected by the disc gel electrophoresis, and were identified in both of white and black sesame. The salt soluble protein of white sesame could be purified by Sephadee G-100 and G-200.

• Analytical Science and Technology
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• v.11 no.4
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• pp.231-234
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• 1998

Separation factor for $^6Li$ and $^7Li$ has been determined using ion exchange resin having 1,7,13-trioxa-4,10,16-triazacyclooctadecane ($N_3O_3$) as an anchor group. The ion exchange capacity of the $N_3O_3$ ion exchanger was 2.0 meq/g dry resin. The lighter isotope, $^6Li$, is concentrated in the fluid phase, while the heavier isotope, $^7Li$, is enriched in the resin phase. By column chromatography [0.3 cm(I.D)${\times}$30 cm (height)] using 3.0 M ammonium chloride solution as an eluent, single separation factor, ${\alpha}$, 1.018, i.e. $(^7Li/^6Li)_{resin}/(^7Li/^6Li)_{fluid}$ was obtained by the Glueckauf theory from the elution curve and isotope ratios.

• Applied Biological Chemistry
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• v.49 no.1
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• pp.70-76
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• 2006

Purecell, hydroxyethyl-cellulose-2-hydroxypropyltrimethyl ammonium chloride ether, was developed as a thickener and evaluated its functions for stability and safety when it was added in the cosmetic composition. Compared with a commercially available thickener Natrasol, Purecell have a basic chemical backbone of hydroxyethylcellulose which has been widely used in the cosmetic industry. pH and viscosity of Purecell was lower than those of Natrasol, however, a similar pH value to was shown when the Purecell was added into a shampoo or cream. The Purecell was stable to temperature and light. When 0.5% of the Purcell was added to a shampoo having cationic surfactant, a separation occurred due to the same cationic surfactant of the Purecell and shampoo. However, the shampoo and cream made with Purecell improved a smoothness and adaptability of hair. It also showed a negative response for Patch test of human, indicating the Purecell was safe for use.

• Analytical Science and Technology
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• v.24 no.2
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• pp.94-104
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• 2011

Mesoporous silica was synthesized in a water solvent and in an ethanol solvent with the non and cationic cetyltrimethyl ammonium chloride (CTAC) by varying the amount of the amphiphilic acrylic urethane oligomer (AAU) and the pH of the solution. The adsorption of the MX (3-chloro-4 (dichloromethyl)-5-hydroxy-2-(5H)-furanone) in drinking water was studied using the synthesized mesoporous silica as an adsorbent. The most appropriate silica was synthesized in acidic conditions in the water solvent and in alkali conditions in the ethanol solvent. The average pore sizes of the synthesized mesosilica were 3 nm and more. The mesoporous silica synthesized by the addition of the AAU oligomer showed excellent adsorption characteristics. With respect to the co-surfactant, the best adsorption characteristics were obtained when the P64,a non-ionic surfactant with a high molecular weight, was used to synthesize the silica than when other co-surfactants were used. The adsorption rate decreased as the MX concentration in the water increased. Different adsorption equilibrium conditions were reached depending on the adsorbate MX concentration in the adsorbent and the solution. It was seen that perfect adsorption does not occur due to such equilibrium conditions.

• Asian Journal of Turfgrass Science
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• v.5 no.1
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• pp.47-53
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• 1991

A laboratory experiment was conducted in order to learn the effect of a number of organic matters on the ammonification and nitrification of urea, and the reaction of soil, applied to a loamy upland soil poor in orgnic matter(<1.5%, without plants 1.The ammonification of urea was most pronounced in one week period immediatly after fertilizer and water treated, after which a rapid decrease of it was followed showing no accumulation at the end of 3rd week. Owing to the accumlation of ammonium, pHs of treated soils were read 7.0 to 7.3 from 6.8~6.9. 2.Nitrification was also progressed rapidly in the first one week period so that the accumulation of NO$_3$-N surpassed that of ammonia during this period. After the 1st week the accumulation of N0$_3$-N was continuously increased showing the maximum at the end of 4 weeks following a sharp decrease at the end of 5th weeks. The accumulation of NO$_3$-N dropped soil pH from 6.8-7.0 to 6. 0-6.2,but the decrease of NO-N at the end of 5th weeks brought up soil pH to 6.4-6.6. again. 3.Amino acid fermentation byproduct rich in salt, paticularly chloride, slowed down the ammonification and nitrification of urea. 4.The application of organic matter diminished the acidifying effect of chemical fertilizers. The diminishing effect of soluble humic acid and amion acid fermentation byproduct showed greater than that of solid organic matter in this experiment, which might be own to the application of a rather small amount of water soluble organic matters. Rice straw powder among solid organic matters appeared to be the least in the diminishing effect above. It may be reasoned that these soluble organic matters decomposes rapidly so as to affect Soil pH, but solid organic matters, particularly the rice straw powder, form acidic humus.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1720-1726
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• 2014

(S)-Alanine Racemase Chiral Analogue ((S)-ARCA) was used as an efficient adsorbent for the selective separation of D-amino acids (D-AAs), which are industrially important as chiral building blocks for the synthesis of pharmaceutical intermediates. The organic phase, containing (S)-ARCA adsorbent and phase transfer reagents, such as ionic liquid type molecules (Tetraphenylphosphonium chloride (TPPC), Octyltriphenylphosponium bromide (OTPPBr)), were coated on the surfaces of mesoporous carbon supports. For the immobilization of chiral adsorbents, meso/macroporous monolithic carbon (MMC), having bimodal pore structures with high surface areas and pore volumes, were fabricated. The separation of chiral AAs by adsorption onto the heterogeneous (S)-ARCA was performed using a continuous flow type packed bed reactor system. The effects of loading amount of ARCA on the support, the molar ratio of AA to ARCA, flow rates, and the type of phase transfer reagent (PTR) on the isolation yields and the optical purity of product D-AAs were investigated. D-AAs were selectively combined to (S)-ARCA through imine formation reaction in an aqueous basic solution of racemic D/L-AA. The (S)-ARCA coated MMC support showed a high selectivity, up to 95 ee%, for the separation of D-type phenylalanine, serine and tryptophan from racemic mixtures. The ionic liquids TPPC and OTPPBr exhibited superior properties to those of the ionic surfactant Cetyltrimethyl ammonium bromide (CTAB), as a PTR, showing constant optical purities of 95 ee%, with high isolation yields for five repeated reuses. The unique separation properties in this heterogeneous adsorption system should provide for an expansion of the applications of porous materials for commercial processes.

• Biomolecules & Therapeutics
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• v.9 no.3
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• pp.201-208
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• 2001

The present study was conducted to examine the effects of cholinergic stimulation and membrane depolarization on secretion of epinephrine (EP) and norepinephrine (NE) in the perfused model of the rat adrenal gland and to investigate the effect of bromocriptine on secretion of EP and NE evoked by these secreta-gogues. Acetylcholine (ACh, 5.32 mM), high $K^{+}$(56mM), 1.1-dimethyl-4-phenyl piperazinium iodide (DMPP, 100 $\mu$M for 2 min), (3-(m-cholro-phenyl-carbamoyl-oxy)-2butynyl trimethyl ammonium chloride (McN-A-343, 100 $\mu$M for 2 min), cyclopiazonic acid (10 $\mu$M for 4 min) and methyl-1,4-dihydro-2,6-dimethyl-3-nitro-4-(2-trifluoromethylphenyl) -pyridine-5-carboxylate (Bay-K-8644, 10 $\mu$M for 4 min) evoked a 1.3~5.3-fold greater secretion of EP than NE in the perfused rat adrenal gland. The perfusion of bromocriptine (1-10 $\mu$M) into an adrenal vein for 20 min produced relatively dose-dependent inhibition in secretion of EP and NE evoked by ACh, high $K^{+}$, DMPP, and McN-A-343. Moreover, under the presence of bromocriptine (1~10 $\mu$M), releasing responses of EP and NE evoked by cyclopiazonic acid and Bay-K-8644 were also greatly reduced. Taken together, these results suggest that cholinergic stimulation and membrane depolarization enhance more release of EP than NE in the perfumed rat adrenal medulla, and that bromocriptine inhibits the release of EP and NE evoked by stimulation of cholinergic receptors as well as by membrane depolarization. It seems that this inhibitory effect of bromocriptine is associated with inhibition of calcium channels through activation of dopaminergic D2-receptors located in the rat adrenomedullary chromaffin cells.lls.

• Journal of the Korean Chemical Society
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• v.7 no.1
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• pp.17-24
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• 1963

The fundamental investigations of surface properties of scheelite were made by electrophoretic mobility adsorption and contact angle measurements, and results have been correlated with its floatability obtained by Hallimond tube flotation test. The role of the interfacial electrical condition on the adsorption of collectors on mineral surfaces is discussed with the flotation of scheelite. From electrokinetic measurements made on scheelite, $Ca^{++}$ and $WO_4^{--}$ are identified to act as potential-determining ions, thus controlling the surface properties on this mineral. Therefore, at the fixed pH, the scheelite surface become to be less negatively charged with increasing $Ca^{++}$ concentration and more negatively charged with increasing $WO_4^{--}$ concentration in the pulp. Adsorption of collectors then depends strongly on the concentration of $Ca^{++}$ or $WO_4^{--}$ in the solution; anionic collectors are adsorbed on less negatively charged surfaces and cationic collectors on more negatively charged surfaces, which in turn defines the effective flotation range with respective collectors for this mineral.