• KSBB Journal
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• v.19 no.5
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• pp.363-367
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• 2004

Leuconostoc mesenteroides NRRL B-1149 produces various glucoseyltransferases for the synthesis of dextran, levan and glucose-1-phosphate using sucrose as a substrate. A sucrose phosphorylase (1149SPase) was purified from L. mesenteroides NRRL B-1149 culture by using hollow fiber filtration (30 kDa cut off), Toyopearl DEAE 650 M column chromatography and following two times of DEAE-Sepharose column chromatographies. The specific activity of the purified 1149SPase was 25.7 (U/mg) with $16\%$ yield. The 1149SPase showed a molecular size of 56 kDa on denatured $10\%$ SDS-PAGE. The N-terminal amino acid sequence of the enzyme was MEIQNKAM. The optimum pH and temperature of this enzyme were 6.2~6.5 and 37^{circ}C, respectively. It had an apparent K_{m} of 6.0 mM and K_{cat} of 1.62/s for sucrose. 1149SPase crystal was formed by hanging drop diffusion technique using 20 mM calcium chloride dihydrate, 100 mM sodium acetate trihydrate pH 4.6 and $30\%$ 2-methyl-2,4-pentanediol as vaporizing and reservation solution. The 1149SPase catalyzes transferring of glucose from isomaltose or sucrose to salicin and salicyl alcohol by disproportionation reaction or acceptor reaction and synthesized two acceptor products, respectively.

• KSBB Journal
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• v.30 no.6
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• pp.313-318
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• 2015

${\delta}$-Aminolevulinic acid (ALA) is an endogenous metabolite formed in the mitochondria from succinyl-CoA and glycine, and plays a key role in the living body as an intermediate of the compound in the porphyrin biosynthesis pathway. ALA has been commonly used in photodynamic therapy for several years, because ALA is of interest as a biodegradable mediator, a growth regulator, and an effective agent used in dermatology. Here, we determined which ALA derivatives were the most effective for the inhibition of the cell proliferation and growth of human fibroblast. As a result, we found that the treatment of ALA derivatives including ALA, ALAP (ALA phosphate salt), MAL (Methyl 5-aminolevulinate hydrochloride salt), PBGL (phophobilinogen lactam) and PBGH (phophobilinogen-HCl) could attenuate cell proliferation of human fibroblast cells. Among them, PBGH was the most effective derivative. In addition, PBGH treatment could induce mitochondrial membrane depolarization, leading to cell death of human fibroblast. These results suggest that mitochondrial membrane depolarization induced by ALA and PBGH treatment might be responsible for inhibition of cell proliferation and death. Taken together, our results propose the possibility that PBGH can be used as one of the effective drugs in human skin disease, psoriasis.

• Journal of Microbiology and Biotechnology
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• v.24 no.8
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• pp.1123-1132
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• 2014

This study evaluated the growth and nutrient removal ability of an indigenous algal consortium on real untreated municipal wastewater in a high rate algal pond (HRAP). The HRAP was operated semicontinuously under different hydraulic retention times (HRT: 2, 4, 6, and 8 days). The average removal efficiencies of chemical oxygen demand, and total nitrogen and phosphate of real municipal wastewater were maintained at $85.44{\pm}5.10%$, $92.74{\pm}5.82%$, and $82.85{\pm}8.63%$, respectively, in 2 day HRT. Algae dominated the consortium and showed high settling efficiency (99%), and biomass and lipid productivity of $0.50{\pm}0.03g/l/day$ and $0.103{\pm}0.0083g/l/day$ (2day HRT), respectively. Fatty acid methyl ester analysis revealed a predominance of palmitate (C16:0), palmitoleate (C16:1), linoleate (C18:2), and linolenate (C18:3). Microalgal diversity analyses determined the presence of Chlorella, Scenedesmus, and Stigeoclonium as the dominant microalgae. The algal consortium provides significant value not only in terms of energy savings and nutrient removal but also because of its bioenergy potential as indicated by the lipid content (20-23%) and FAME profiling.

• Journal of Pharmaceutical Investigation
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• v.35 no.6
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• pp.431-436
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• 2005

A high-performance liquid chromatographic method was validated for quantitation of nadolol in human plasma. Nadolol and internal standard, pindolol, were extracted with tert-butyl methyl ether after addition of 10 M sodium hydroxide solution. The analytes were separated on a reverse phased C18 column using a mobile phase consisting of 0.05 M ammonium phosphate monobasic buffer, acetonitrile and methanol (81: 17:2 v/v/v) and detected using a fluorescence detector (excitation wavelength 230 nm, emission wavelength 294 nm). The method was specific and sensitive enough to detect as low as 3 ng/mL of nadolol in human plasma. Linear calibration range was 3-150 ng/mL with correlation coefficient greater than 0.999. The overall accuracy was in the range of 96.8 to 103% and precision C.V.(%) 7.30 to 12.2%. The recovery was approximately 100% and stability was confirmed during storage and sample preparation. The present HPLC method was successfully applied to study bioavailability after oral administration of 80 mg of nadolol in healthy Korean subjects. The mean $AUC_{t}$ was $1968{\pm}397\;ng{\cdot}hr/mL$ and $C_{max}$ of $186{\pm}79.3\;ng/mL$ was reached at $3.5{\pm}0.76\;hr$. The mean $t_{1/2}$ of nadolol was $17.3{\pm}2.59\;hr$.

• Journal of the Korean Applied Science and Technology
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• v.29 no.2
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• pp.224-230
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• 2012

In this paper, flame-resisting PMMA(polymethyl methacrylate) sheet was manufactured and its characteristics were tested. PMMA was synthesized by bulk polymerization of a monomer methyl methacrylate with addition of phosphorous flame retardant, triethyl phosphate and ethylene glycol dimethacrylate as a cross linking agent. PMMA sheet was manufactured by using the cell molding method, which does not alter or affect the existing property of PMMA. Then the characteristics of PMMA sheet were tested for the TEP content, the content and curing time of EGDMA. As TEP content increases, the length of carbonization lessens and the amount of char production increases. As a result, it strengthened the effect of flame retardants. But the hardness of the sheet decreased as TEP content increased. However, hardness increased when EGDMA was added up to 3 wt% while curing time was decreased from 3 hours to 2 hours. There was no change of hardness when more than 3 wt% of EGDMA was used.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.7
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• pp.1026-1030
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• 2002

A trial was conducted to investigate the effect of dietary NMA on several growth associated hormones and fat metabolism in finishing pigs. A total of 84 crossbred finishing pigs (average initial BW of $56{\pm}$0.37kg) were divided into 6 pens, 14 pigs per pen (7 gilts and 7 barrows per pen). 3 pens of pigs were fed with control diet (corn-soybean meal) and the others were fed control diet addition with 50 mg/kg NMA. During the trial, all pigs were given free access to feed and water. After 44 days trial, 8 pigs from each treatment (4 gilts and 4 barrows, weight similar to average group weight, $86.94{\pm}0.71kg$ for control group, and $90.55{\pm}1.51kg$ for NMA treated group) were sacrificed to collect the sample of the liver, longissimus muscle, subcutaneous fat (10th rib). The addition of NMA in diet increased the IGF-I, Insulin, T3, T4 levels in serum by 50.68% (p<0.05), 38.36% (p<0.05), 123.33% (p<0.01), 60.58% (p<0.03), respectively. Meanwhile, IGF-I level in the liver and the muscle were increased with 17.83% (p<0.03) and 26.00% (p<0.03) with addition of NMA. The data from subcutaneous fat (10th rib) analysis showed that supplement of 50 mg/kg NMA decreased the total activities of malic dehydrogenase (MDH) by 20.54% (p<0.05), glucose-6- phosphate dehydrogenase (G-6-DPH) by 16.97% (p<0.05), and decreased the specific activities of MDH and G-6-DPH by 37.46% (p<0.01) and 35.06% (p<0.01), respectively. The hormone sensitive lipase (HSL) total activity was increased by 25.00% (p<0.05) in NMA treated pigs. These results indicated that addition of 50 mg/kg NMA to diet can induce the endocrine great change in finishing pigs, furthermore, inhibit the fat synthesis through suppressing lipogenic enzymes and promote the fat degradation by elevating HSL activity in finishing pigs.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1305-1310
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• 2012

Breast cancer cells undergo transformation when they spread into surrounding tissues. Studies have shown that cancer cells undergo surface alterations and interact with the surrounding microenvironment during the invasion process. The aim of the present study was to analyse these cancer cell surface alterations and interactions of cancer cells and stroma. Twenty 1-methyl-1-nitrosourea-induced breast cancer samples taken from five rats were fixed in McDowell-Trump fixative and then washed in 0.1 M phosphate buffer. The samples were then treated with osmium tetroxide before being washed in distilled water and subsequently dehydrated through graded ethanols. The dehydrated samples were immersed in hexamethyldisilazane (HMDS), then following removal of excess HMDS, the samples were air dried at room temperature in a dessicator. The dried samples were mounted onto specimen stubs and coated with gold coater before being viewed under a scanning electron microscope. We detected the presence of membrane ruffles on the surface of cancer cells and the formation of unique surface membrane protrusions to enhance movement and adhesion to the surrounding stroma during the process of invasion. Advancing cancer cells demonstrated formation of lamellipodia and invadopodia. The stroma at the advancing edge was desmoplastic with many collagen fibres laid down near the cancer cells. Our data suggest that all of these abnormalities could act as hallmarks of invasiveness for breast cancer.

• Applied Chemistry for Engineering
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• v.23 no.4
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• pp.367-371
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• 2012

Waste printed circuit boards (WPCBs) contain valuable metals such as Cu, Ni, Au, Ag, and Pd. For an effective recycling of WPCBs, it is essential to recover the valuable metals. In recent years, recycling processes have come to be necessary for separating noble metals from WPCBs due to an increasing amount of electronic device wastes. However, it is well known that glass reinforced epoxy resins in the WPCBs are difficult materials to separate into elemental components, namely metals, glass fibers and epoxy resins in the chemical recycling process. $K_3PO_4$ as a catalyst in dimethylformamide (DMF) and N-Methyl-2-pyrrolidone (NMP) was used to depolymerize epoxy resins for recovering metallic and non-metallic components from WPCBs. Reactions of WPCBs were carried out at temperatures $160{\sim}200^{\circ}C$ for 2~12 h. The recycled glass fiber from WPCBs was analyzed by thermogravimetric analyzer (TGA) and evaluated the degree of solubility of the epoxy resin for separation efficiencies of the WPCBs.

• Ocean and Polar Research
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• v.32 no.3
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• pp.203-212
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• 2010

Distribution of organophosphorous pesticides (OPs) was studied from February to September 2008 in the seawater of Asan Bay, Korea. Among the 29 types of OPs detected during the study period, IBP(S-benzyl O,O-diisopropyl phosphorothioate), ranging from <1 ng/l to 377 ng/l, was the most abundant. Other commonly observed OPs concentrations in the study area included diazinon (Diethyl 2-isopropyl-4-methyl-6-pyrimidinyl phosphorothionate; <1~307 ng/l), azinphos ethyl (3,4-Dihydro-4-oxo-3-benzotriazinylmethyl O,O-diethyl phosphorodithioate; <1~1997 ng/l), malathion (1,2-Di(ethoxycarbonyl)ethyl O,Odimethyl phosphordithioates; <1~3013 ng/l), demeton-O (Diethyl 2-(ethylthio)ethyl phosphorothionate; <1~2403 ng/l), and DDVP (2,2-dichlorovinyl dimethyl phosphate; <1~283 ng/l). Seasonal distribution of OPs in seawater is dependent on the OP application period. In August, OPs concentrations were generally decreased with the increased salinity of seawater, implying progressive dilution of pesticides in the estuarine system. OPs were deposited into Asan Bay from Asan and Sabkyo Lakes as well as surrounding tributaries. Ten OPs, including diazinon, were detected in the suspended particles of Asan Bay.

• Journal of Electrochemical Science and Technology
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• v.7 no.4
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• pp.298-305
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• 2016

The development of non-precious metal based electrocatalysts is highly desired for the oxygen reduction reaction (ORR) as alternates to noble metal based ORR electrocatalysts. Herein, we report mononulcear copper(II) complex $[CuLbpy]ClO_4$ (L=4-[(2-hydroxyphenylimino)methyl]benzoic acid) containing poly(allylamine.HCl) polymer (PAlACuLbpy) as an electrocatalyst for oxygen reduction reaction (ORR). PAlACuLbpy was mixed with poly(acrylic acid) and tetraethylortho silicate to prepare a composite and then deposited on the screen printed electrode surface. The modified electrode (PAlACuLbpy/PCE) is highly stable and showed a quasi-reversible redox behavior with $E_{1/2}=-0.2V$ vs. Ag/AgCl(3 M KCl) in 0.1 M phosphate buffer at pH 7 under argon atmosphere. PAlACuLbpy/PCE exhibited a remarkable ORR activity with an onset potential of -0.1 V vs Ag/AgCl in 0.1 M PB (pH 7) in the presence of oxygen. The kinetics for ORR was studied by rotating disk voltammetry in neutral aqueous medium and the results indicated that the number of electrons involving in the ORR is four and the conversion products are water and hydrogen peroxide.