• Bulletin of the Korean Chemical Society
• /
• v.28 no.10
• /
• pp.1867-1870
• /
• 2007

• YAKHAK HOEJI
• /
• v.47 no.2
• /
• pp.110-119
• /
• 2003

The purpose of the present study was to kinetically investigate the carrier-mediated uptake in the hepatic transport of organic anions, and to simulate the ″in vivo counter-transport″ phenomena, using kinetic model which was developed in this study. The condition that the mobility of carrier-ligand complex is greater than that of free carrier is not essential for the occurrence of ″counter-transport″ phenomenon. To examine the inhibitory effects on the initial uptake of a ligand by the liver, it is necessary to judge whether the true counter-transport mechanism (trans-stimulation) is working or not. The initial plasma disappearance curves of a organic anion were then kinetically analyzed based on a flow model, in which the ligand is eliminated only from the peripheral compartment (liver compartment). Moreover, ″in vive counter-transport″ phenomena were simulated based on the perfusion model which incorporated the carrier-mediated transport and the saturable intracellular binding. The ″in vivo counter-transport″ phenomena in the hepatic transport of a organic anion were well demonstrated by incorporating the carrier-mediated process. However, the ″in vivo counter-transport″ phenomena may be also explained by the enhancement of back diffusion due to the displacement of intracellular binding. In conclusion, one should be more cautious in interpreting data obtained from so-called ″in vivo counter-transport″ experiments.

• Bulletin of the Korean Chemical Society
• /
• v.23 no.1
• /
• pp.119-122
• /
• 2002

Weakly coordinating anions show little affinity for binding to unfunctionalized iron(II) porphyrins. The electron-deficient 5, 10, 15, 20-tetrakis(pentafluorophenyl)porphinatoiron(II) compound is utilized in this study to demonstrate solution coordination by chloride, bromide and acetate ions. The binding strength of anions to the iron(II) porphyrin is reflected by a systematic change in pyrrole proton chemical shift in $^1H$ NMR spectra; the pyrrole resonance moves downfield when the ${\sigma}$-donor ability of anions is decreased.

• The Korean Journal of Zoology
• /
• v.37 no.1
• /
• pp.66-75
• /
• 1994

Juvenile hormone binding protein was identified in the hemolymph of fifth instar larvae and purified using column chromatography. Hemolymph was mixed with [3H] JH-III and electrophoresed on 691 NON-SDS gel, indicating that radioactivity peak appears at Rf value of 0.55. Gel filtration showed two radioactivity peaks equivalent to bound and free [3H]JH-III, respectively. JHBP was purified from hemolymph through gel filtration (Sephadex G-100), anion exchange chromatosraphv (DEAE Sepharose CL-6B), chromatofocusing chromatographv (PBE 94) and preparative electrophoresis.

• Proceeding of EDISON Challenge
• /
• 2013.04a
• /
• pp.77-88
• /
• 2013

The computational study on the fluoride ion binding with bis(bora)calix[4]arene has been performed using density functional theory and ONIOM model. The computed structure and fluorescent behavior of bis(bora)calix[4]arene was corresponded to experiment value. The binding energy for fluoride anion is computed to be 28.05kJ/mol in the chloroform solution. We also predicted that this sensing mechanism is only valid for fluoride ion in halogens. By analyzing molecular orbitals, binding with fluoride ion reduces energy differences between HOMO and LUMO, which leads to fluorescent sensing.

• Journal of Microbiology
• /
• v.37 no.1
• /
• pp.21-26
• /
• 1999

Two novel calcium-binding proteins, named CAB-I and CAB-II, have been isolated from Streptomyces coelicolor. Purification of the calcium-binding proteins involved heat treatment, fractionation with ammonium sulfate, acid treatment, anion exchange and hydrophobic interaction column chromatography, FPLC gel filtration, and preparative isoelectric focusing. A chelex competitive assay and 45Ca autoradiography verified the calcium-binding ability of the proteins. The major band CAB-II has an apparent molecular weight of 26,000 determined by SDS-polyacrylamide gel electrophoresis and 340,000 determined by gel filtration. The isoelectric point of this molecule showed the acidic nature of the molecule. N-terminal amino acid sequence analysis shows homology to rat Ca2+/calmodulin-dependent protein kinase-II (CAB-II) and yeast phosphoprotein phosphatase (CAB-I).

• Journal of Life Science
• /
• v.26 no.3
• /
• pp.346-352
• /
• 2016

Aroma inhalation therapy has traditionally been used not only in alternative medicinal treatment but also in psychotherapy. In the first stage of the study, the in silico molecular binding affinity of the major ingredients of Smart-Wave (SW) on the active site of the odorant-binding protein (OBP) was compared with that of citrate anions. The binding affinity of the chemical mixture formula of the major ingredients of SW on the OBP was relatively higher than that of citrate anions. In addition, nasal inhalation of SW had a positive effect upon changes in brain waves. Eighteen healthy volunteers participated in the experiment. The study consisted of measurements of the brain’s meditation level recordings in the pre- and post-SW inhalation periods as compared with negative (EV) and positive (HB) control groups. After SW inhalation, all the subjects stated that they felt “fresher” and that the SW trial group had significantly changed the brain’s meditation in a positive way. SW inhalation also converted EV-induced unstable brain meditation wave patterns into more stable patterns. Collectively, the results of this empirical study strongly suggest that the SW mixture activates the OBP and controls the mental state by regulating brain waves. The results provide scientific evidence that the SW formula has potential as an effective mental-stress controller.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.9
• /
• pp.2101-2106
• /
• 2009

A series of facial amphiphiles 3,7-diaminocholestane were synthesized from 3,7-diketocholestane via 2 sequential reductive aminations and anion recognition was evaluated with acetate, chloride, bromide, fluoride and phosphate anions. The stereo-selective reductive amination protocol was utilized to synthesized facial amphiphiles afforded receptors in high yields. The molecular receptor 2 showed the highest binding constant with acetate in a 1:1 ratio.

• Journal of Environmental Science International
• /
• v.8 no.2
• /
• pp.205-209
• /
• 1999

Iron hydroxides are good adsorbents for uncomplexed metals, some metal-ligand complexes and many metal oxyanions. However, their adsorption properties of these precipitations are not fully exploited in wastewater treatment operations because of difficulties associated with their separation from the aqueous phase. This study describes experiments in which iron hydroxides were coated onto the surface of ordinary adsorbents(Sea sand) that are very resistant to acids, The coated adsorbents were used in adsorption of oxyanionic metals. The process was successful in removing some anions such as $SeO_3(-II)$ over a wide range of metal concentrations and sorption of oxyanionic metals increased with decreasing pH. Formation of two surface complexes for oxyanionic metals adsorption on iron hydroxides comprise (1) complexation of the free anion by a positively charged surface site, and (2) protonation of the adsorbed anion (or alternatively adsorption of a protonated form from solution) The coated adsorbents are inexpensive to prepare and could serve as the basis of a useful oxyanionic metal removal.

• Proceedings of the Membrane Society of Korea Conference
• /
• 2004.11a
• /
• pp.142-145
• /
• 2004

Anion-exchange porous hollow-fiber membranes with a thickness of about 1.2 mm and a pore size of about $0.30{\mu}m$ were used as a supporting matrix to immobilize cycloisomaltooligosaccharide glucanotransferase (CITase). CITase was immobilized to the membrane via anion-exchange adsorption and by subsequent enzymatic cross-linking with transglutaminase, the amount of which ranged from 3 to 110 mg per g of the membrane. The degree of enzyme multilayer binding was equivalent to 0.3 to 9.8. Dextran, as the substrate, was converted into seven- to nine-glucose-membered cycloisomaltooligosaccharides (CI-7, -8, and -9) at a maxi mum yield of $28\%$ in weight at a space velocity of 10 per hour during the permeation of $2.0(w/w)\%$ dextran solution across the CITase-immobilized porous hollow-fiber membrane.