• Biotechnology and Bioprocess Engineering:BBE
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• 제11권4호
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• pp.277-281
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• 2006

Spherical micro silica sol-gel immobilized enzyme beads were prepared in an emulsion system using cyclohexanone and Triton-X 114. The beads were used for the in situ immobilization of transaminase, trypsin, and lipase. Immobilization during the sol to gel phase transition was investigated to determine the effect of the emulsifying solvents, surfactants, and mixing process on the formation of spherical micro sol-gel enzyme beads and their catalytic activity. The different combinations of sol-gel precursors affected both activity and the stability of the enzymes, which suggests that each enzyme has a unique preference for the silica gel matrix dependent upon the characteristics of the precursors. The resulting enzyme-entrapped micronsized beads were characterized and utilized for several enzyme reaction cycles. These results indicated improved stability compared to the conventional crushed form silica sol-gel immobilized enzyme systems.

• 대한화학회지
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• 제59권5호
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• pp.407-412
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• 2015

A preconcentration procedure for determination of palladium by laser thermal lens spectrometry (TLS) is proposed. It is based on cloud point extraction of palladium(II) ions as 2-(3,5-dichloro-2-pyridylazo)-5-dimethylaminoaniline (3,5-diCl-PADMA) complexes using octylphenoxypolyethoxyethanol (Triton X-114) as surfactant. The effects of various experimental conditions such as pH, concentration of ligand and surfactant, equilibration temperature and time on cloud point extraction were studied. Under the optimized conditions, the calibration graph was linear in the range of 0.15~6 ng mL⁻¹, and the detection limit was 0.04 ng mL⁻¹ with an enrichment factor of 22. The sensitivity was enhanced by 846 times when compared with the conventional spectrophotometric method. The recovery of palladium was in the range of 96.6%~104.0%. The proposed method was applied to the determination of palladium in water samples.

• Bulletin of the Korean Chemical Society
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• 제25권8호
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• pp.1133-1136
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• 2004

The need for highly reliable methods for the determination of trace metals is recognized in analytical chemistry and environmental science. A method based on the cloud-point extraction (CPE) technique for the trace analysis of Pb and Cu in water samples is described in this study. The analytes in the initial aqueous solution are complexed with pyrogallol, and 0.1%(w/v) Triton X-114 is added as surfactant. Following phase separation at $50^{\circ}C$, based on the cloud point of the mixture and dilution of the surfactant-rich phase with acidified methanolic solution, the enriched analytes are determined by flame atomic absorption spectrometry. After optimization of the complexation and extraction conditions, the enrichment factors of Pb and Cu were found to be 72 and 85, respectively. Under optimum conditions, the preconcentration of 60 mL of samples in the presence of 0.1%(w/v) Triton X-114 permitted the detection of 0.4 ${\mu}gL^{?1}$ of Pb and 0.05 ${\mu}gL^{?1}$ of Cu. The proposed method was applied successfully to the determination of Pb and Cu in water samples.

• 한국식품영양과학회지
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• 제37권11호
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• pp.1507-1514
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• 2008

본 연구에서는 산업적으로 사용될 수 있는 안정하고 활성이 높은 cholesterol oxidase를 생산하는 균주를 얻기 위해 토양 미생물로부터 균주를 선별하였다. 선별된 균주에 대하여 세포외 효소 활성을 측정한 결과 BEN 115로 명명한 균주가 가장 높은 효소 활성도를 나타내었다. 이 균주는 형태학적, 생리학적 특성과 배양형태 및 G＋C 함량을 분석한 결과 Nocardia속으로 확인되었다. 최적 효소 생산 조건을 조사한 결과 기존 yeast malt extract broth 조성인 0.4% yeast extract, 0.4% glucose, 1% malt extract에서 가장 높은 활성을 나타냈다. 본 균주에서 생산된 extracellular cholesterol oxidase는 SDS-PAGE와 Western blot 결과 분자량이 55, 57 kDa인 두 종류의 효소가 존재하는 것으로 나타났다. BEN 115에 대한 효소학적 특성을 연구한 결과 온도 안정성은 $55^{\circ}C$까지 효소 활성이 유지되었고, pH 안정성은 pH $3.5{\sim}9.5$의 범위까지 안정한 것으로 나타났으며 최적 온도와 최적 pH는 각각 35oC와 pH 5.5인 것으로 나타났다. 또한 detergent(Triton X-100, Triton X-114 그리고 Tween 80) 첨가 시 효소 활성이 첨가하지 않은 대조군보다 약 $1.6{\sim}2.0$배 증가하는 것으로 나타났다. Campesterol, sitosterol 그리고 stigmasterol에 대한 기질 특이성은 cholesterol(100%)과 상대적으로 비교 시 각각 50%, 50% 그리고 27%의 기질 특이성을 나타내었다.

• 대한화학회지
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• 제52권2호
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• pp.140-147
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• 2008

추출- 전열 원자 흡수 분광법에 대한 새로운 시도가 비스머스 측정에 사용되었다.수용액 분석물은 황산으로 산성화하였다(pH 3.0-3.5). Triton X-114는 계면활성제로 가하였고, natriumdiethyldithiocarbaminat(Na-DDTC)는 착체 시약으로 사용했다. 혼합물의 흐림점 분리를 기저로한 50oC에서 상분리 후에 많은 계면활성제는 tetrahydrofuran(THF)로 희석했다. 농축 용액의 20L와 화학개질제로 0.1% (w/v) Pd(NO3)2를 10? 그라파이트 튜브안으로 분산시켰다. 분석물은 전열 원자 흡수 분광법으로 측정했다. 추출 조건과 기기 파라메타의 최적화 후에 195의 예비농축 인자를 10mL의 시료에서 얻었다. 검출한계는 0.04 ng ml1 분석곡선은 0.04-0.70 ng mL1의 농도범위에서 선형을 얻었다. 상대표준편차는 5% 보다 적었다. 이 방법은 성공적으로 추출과 물시료에서 비스머스 추출과 검출에 적용되었다.

• 대한수의학회지
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• 제50권4호
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• pp.285-295
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• 2010

Protein expression patterns in Salmonella enterica subspecies enterica serovar Typhimurium (S. Typhimurium) strains with diverse phenotypes, such as phage type, antibiotic resistance pattern and plasmid profiles were examined. For detailed analysis of proteins expressed by different S. Typhimurium strains, protein fractions were divided into detergent-rich phase (DP) and aqueous phase (AP) using triton X-114 detergent. The two phases were subjected to two-dimensional gel electrophoresis (2-DE), followed by protein identification using peptide mass fingerprinting (PMF). In the results, PMF showed that DP fractions consisted mainly of outer membrane proteins, whereas the AP fractions included cytosolic proteins. Comparison of 2-DE profiles of DP did not show any distinct protein spots which could be correlated with phage type, antibiotic resistance pattern or plasmid profile. However, comparisons of 2-DE profiles of the AP revealed differences in the protein spots, which could be correlated with the plasmid profile and phage types. Among these protein spots, flagellin was specific for strains containing a 90 kb plasmid. Compared to DT193 phage type, three protein spots in the range of pI 5.0-5.5 and MW 8-15 kDa of AP 2-DE profiles were absent in the DT104 phage types. Additionally, a protein spot with PI in the range of 4.5-5.0 and molecular weight (MW) between 51-69 kDa was specific for phage type DT104, while a protein spot with pI in the range of 4.0-4.8 and MW between 18-20 kDa was specific for DT193 phage type. These protein spots may be useful for discriminating phage types of S. Typhimurium.

• 한국식품과학회지
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• 제27권5호
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• pp.658-665
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• 1995

Pectinestrase(PE) 중에 열에 안정한 thermostable pectineterase(TSPE)를 열에 불안정한 thermolabile pectinesterase(TLPE)로부터 구분하기 위하여 $70^{\circ}C$에서 $5{\sim}10$분간 가열 처리하였다. TSPE의 추출 수율을 증가시키기 위하여 추출시간, pH, 온도, NaCl의 농도 그리고 세포벽을 분해하는 가수분해 효소의 사용 등 여러가지 변화를 주어 개발한 최적 조건은 오렌지 착즙액의 pH 4.14와 같은 1 M NaCl의 acetate buffer에 분말시료의 0.2% $Cytolase^{TM}$ 104(cellulase hemicellulase와 pectinase의 혼합물) 첨가하여 가수분해하여 추출하는 것이었다. 증류수로 추출하거나 황산암모늄 $0{\sim}0.3$ 포화도의 분획은 목적으로 하는 PE 이외의 단백질을 제거하는 수단으로 이용할 수 있었다. 또한 5.0% Triton TX-114의 두가지 액상을 이용한 분배의 방법은 추출한 조효소로부터 TLPE와 TSPE를 분리하는 수단으로 이용할 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제27권10호
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• pp.1604-1608
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• 2006

A simple and efficient cloud point extraction-spectrofluorimetric method for the determination of thiamine in human urine is proposed. The procedure is based on the oxidation of thiamine with ferricyanide to form thiochrome, its extraction to Triton X-114 micelles and spectrofluorimetric determination. The variables affecting oxidation of thiamine, extraction and phase separation were studied and optimized. Under the experimental conditions used, the calibration graphs were linear over the range 2.5-1000 ng $mL^{-1}$. The limit of detection was 0.78 ng $mL^{-1}$ of thiamine and the relative standard deviation for 5 replicate determinations of thiamine at 400 ng $mL^{-1}$ concentration level was 2.42%. Average recoveries between 93-107% were obtained for spiked samples. The proposed method was applied to the determination of thiamine in human urine.

• Bulletin of the Korean Chemical Society
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• 제27권11호
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• pp.1780-1784
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• 2006

Cloud point extraction was used to extract mefenamic acid (MF) from human urine, and spectrofluorimetry and spectrophotometry were used to analyze extracted MF. The variables affecting extraction and phase separation, i.e. HCl and Triton X-114 concentration, temperature and time of equilibration, were optimized. Under the experimental conditions used the limit of detection for extraction of 25 mL of sample was 0.006 and 0.045 mg $L^{-1}$, with relative standard deviations of 2.52 and 1.45% (n = 5) for spectrofluorimetric or spectrophotometric methods, respectively. Good recoveries in the range of 95-107% were obtained for spiked samples. The proposed methods were applied to the determination of MF in human urine.

• 한국세라믹학회지
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• 제44권10호
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• pp.574-579
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• 2007

Porous $Al_2O_3$ ceramics were prepared by the gelcasting foams method (a slurry foaming process) with acrylamide monomer. The foaming and gelation behavior was investigated with the parameters such as the type and concentration of surfactant, solid loading of slurry, and the concentrations of initiator and catalyst. Density, porosity, microstructure, and strength of the green and sintered samples were characterized. Of the four kinds of surfactants tested, Triton X-114 showed the highest foaming ability for the solid loading of 55-30 vol%. The gelation condition giving the idle time off min was found to set the foamed structure without significant bubble enlargement and liquid lamella thinning. The green samples were fairly strong and machinable and showed maximum strength of 2.4 MPa in diametral compression. The sintered samples showed densities of 10-36% theoretical (i.e. porosity 90-64%) with a highly interconnected network of spherical pores with sizes ranging from 30 to $600{\mu}m$. The pore size and connectivity increased but the cell strut thickness decreased with decreasing the solid loading. Flexural strength of 37.8-1.7 MPa was obtained for the sintered samples.