• 한국해양학회지
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• v.4 no.2
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• pp.83-86
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• 1969

해양관측의 세계적인 공통성으로 해서 염분검정법이 이미 오래 전부터 통일화 되었지만 근래에 와서는 용존산소량 정량법도 국제적인 Intercalibration을 하는 등규격화에의 기운이 나고 있다. 다시 Kuroshio 합동조사에서는 영양염의 정량에 있어 공통된 표준용액을 사용하므로써 조작상의 편리와 측정치의 신뢰성을 더욱 향상시키자는 의도에서 일본이 국제적인 영양염 표준용액의 조제 및 배포에 관한 안을 내어 1965년 Manila 회의를 거쳐 일본 상모중앙화학연구소의 관원씨가 이를 맡아 1966년부터 시작하여 1967년까지에 요오드산칼리움, 아질산염, 인산염, 규산염의 표준용액을 만들어 1968년 봄부터 시험적으로 일본국내와 동남아 수개국에 나누어 사용해 왔던 것이다. 다시 1968년 9월의 SCOR 의 영양염에 관한 Working Group 회의에서 CSK Std. Solution을 사용하여 세계각국에서 현재 사용하고 있는 영양염 분석방법의 Intercalibration을 하자는 회의가 있었고, 이것을 권고사항으로 SCOR에 보고하여 1968년 11월에 ICES가 승인하므로써 Intercalibration에 관한 원칙이 정해졌다. 동시에 Finland의 Koroleff씨와 Palmork씨가 organizer로 정해졌던 것이다. 이 보다 약간 앞서 본인이 상모중연에 가 있을 때 Std. Solution으로서 아질산염용액 만으로 각종무기질소화합물의 표준용액으로 대용한다는 것은 비합리적이므로 질산염과 암모늄염의 표준용액이 있어야 한다고 주장하여 우선 질산염용액을 추가로 만들기로 하여 1968년 11월부터 표준물질의 정제부터 시작 되었다. 1969년 1월에 Intercalibration 에 관한 구체적인 회의를 위해 Scripps 해양연구소에 관원, Wooster Rakestraw, Cieskes씨등이 모여 우선 일본상모중연에서 만들고 있는 인산염, 질산염, 아질산염, 규산염의 CSK 표준용액을 표준시료로하여 SCOR 과 ICES의 해양화학분과에서 선정한 세계 100개처에 나누어 현재 각자가 사용하고 있는 방법의 정밀도와 정확도를 check하는 소위 International intercalibration을 1969년 9월부터 시작하기로 확정을 보았고, 동시에 구체적인 지시가 있었던 것이다. 이시료를 받는 사람에게는 다만 그것의 농도범위만 알려주고 정확한 농도는 Koreleff와 관원씨만이 알고 있기로 하여 측정에 분석자의 주관이 개입되지 못하도록 했고, 분석치는 SCOR가 모아 해석하되 번호제로 하여 어떤 나라의 누구가 했다는 것은 밝히지 않기로 되어 있다. 이같은 내력으로 CSK Std. Solution이 국제적인 Intercalibration용의 표준시료로서 시험적으로 사용되기 까지는 되었으나, CSK Std. Solution 그자체에 관해서는 아직도 해결해야 할 점, 개량을 요하는 점이 많다. 이하에서는 주로 개량을 요하는 점에 관해 몇가지 언급하고자 한다.

• Microbiology and Biotechnology Letters
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• v.26 no.4
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• pp.283-289
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• 1998

A bacterial strain KH-95 producing a high concentration of red pigment was isolated from the soil. The strain KH-95 was identified as a strain of Serratia sp. based on morphological and physiological characteristics. The optimal temperature and initial pH range for the production of pigment were 28$^{\circ}C$ and 7.0-8.0, respectively. The red pigment was purified through solvent extraction and silica gel column chromatography. Analyzing the structure of this pigment by instrumental analysis, it was identified as prodigiosin-like compound. In optimization of carbon and nitrogen sources, all carbon sources tested in this work inhibited the production of pigment except oils. Casein fumed out to be the most suitable nitrogen source for pigment production. Other nitrogen sources such as yeast extract, beef extract and peptone showed good cell growth but potently inhibited the production of pigment.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.318-322
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• 1997

As an investigation for utilization of squid viscera oil as a food source, we attempted to improve a quality of fish burger by addition of emulsion curd formed from gelatin, water and refined squid viscera oil. Judging from the results of peroxide value, brown pigment formation, color value of Hunter, jelly strength and sensory evaluation, the reasonable amount of emulsion curd for the improvement of a fish burger functionality was determined as 6% on the weight basis of the chopped mackerel meat. Total plate counts, volatile basic nitrogen and histamine contents in fish burger prepared by addition of 6% of emulsion curd were $6.2{\times}10^4\;CFU/g$, 19.0 mg/100 g, and 50.7 mg/100 g, respectively. It may be concluded, from the above results that the emulsion curd-added fish burger is a safe as a food commodity. The ratio of polyenes to saturates of emulsion curd-added mackerel burger was 1.13. By adding emulsion curd formed from gelatin, water and refined squid viscera oil, color in cross section, texture and lipid functionality of mackerel burger could be improved in part.

• Microbiology and Biotechnology Letters
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• v.1 no.1
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• pp.13-18
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• 1973

For the production of Nucleic acid derivatives by microorganisms, adenineless mutants were induced from Bacillus subtilis with the mutagens, ultraviolet rays and diethylsulfate. And total strains of 62 adenineless mutants were isolated. These mutants were found to have an ability of accumulating u. v. absorbing substances in the culture broth. They were analyzed to be hypoxanthine, uracil, and other unknown compound by means of two dimensional thin layer chromatography, u. v. absorption spectra, and I. R. absorption spectrum. Mutant BS-137 was screened out to accumulate hypoxanthine, which was isolated from the culture broth through activated carbon column and recrystallize from cold water. The effect of the medium compositions on hypoxanthine accumulation were examined for the mutant BS-137. Glucose appeared to be the best carbon source, but molasses could be substitute for it, NaNO$_3$ and yeast extract were especially good sources of nitrogen.

• Microbiology and Biotechnology Letters
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• v.18 no.3
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• pp.273-279
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• 1990

For poly- $\beta$ -hydroxybutyrate (PHB) production, a pink-pigmented facultative methylotrophic bacterium (PPFM) P-10 was newly isolated from soils through methanol-enrichment culture. The optimal medium composition for cell growth was 1.0% (vlv) of methanol as carbon source and l.Og/l of ,TEX>$NH_4Cl$, equivalent to C/N ratio of 13.2 at pH 7.0 and $30^{\circ}C$. To investigate the optimal condition for YHB accumulation, two-stage culture technique was adopted; first stage for cell growth and second stage for accumulation of PHB providing unbalanced growth conditions. The optimal PHB accumulation was 1.0% (vIv) of methanol and 0.26gll of $NH_4Cl$, C/N of 50.8 at pH 6.0. To overcome methanol inhibition on cell growth, intermittent feeding fed-batch culture technique was employed, and the cell concentration as high as 14gll with 40% of PHB was achieved. The purified PHB was identified using IR and $1^H NMR$ as homopolymer of 8hydroxybutyric acid. The absorption spectrum of extracted pink colored microbial pigment was alsa investigated.

• Journal of Korea Soil Environment Society
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• v.4 no.2
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• pp.33-43
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• 1999

A strain (designated SK3l) which produces an excellent adsorption substance was isolated from soil samples and identified as Bacillus specied. The major adsorption substance (biosorbent SK3l) produced by Bacillus sp. SK31 was purified by ethanol precipitation and cetylpyridinium (CPC) precipitation. The adsorption charactics of zinc and lead ions on bioadsorbent SK3l were investigated. The equilibrium isotherms showed that bioadsorbent SK3l took up zinc and lead from aqueous solutions to the extent of about 52 mg/g and 112 mg/g. respectively. The culture conditions at the flask level of Bacillus sp. SK3l were investigated for the production of polysaccharide bioadsorbent, SK3l. The optimum pH and temperature for sorbent production were 7.5 and $30^{\circ}C$, respectively. The important carbon and nitrogen sources for sorbent formation were glucose and ammonium nitrate, respectively. In the optimized medium, sorbent production was improved three folds in comparison with the basal medium. In the jar fermenter, the highest sorbent production was obtained at 60 h cu1tivation time and the amount of biosorbent SK3l at that time was 9.2 g/$m\ell$.

• Korean Journal of Microbiology
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• v.41 no.1
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• pp.13-17
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• 2005

The aim of this work was to investigate the N-terminal amino acid sequence of catechol 2,3-dioxygenase isolated from Delftia sp. JK-2, which could utilize aniline as sole carbon, nitrogen and energy source. Molecular weight of the enzyme was determined to approximately 35 kDa by SDS-PAGE. N-terminal amino acid sequence of C2,3O from strain JK-2 was $^1MGVMRIGHASLKVMDMDAAVRHYENV^{26}$, and exhibited high sequence similarity with that of C2,3O from Pseudomonas sp., Comamonas sp. JS765, Comamonas test-osteroni, or Burkholderia sp. RP007. Approximately 950-bp C2,3O was obtained through PCR using the primers derived from N-terminal amino acid sequence. Analysis of the DNA sequence revealed that the deduced 296 amino acid sequences were determined, and it showed $100\%$ identity with C2,3O from Pseudomonas sp. AW-2 and $97\%$ similarity with Comamonas sp. JS765.

• Journal of the Korean Chemical Society
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• v.37 no.7
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• pp.642-647
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• 1993

Monolayers of pure surfactant squaraine, DSSQ(4-distearyl amino phenyl-4'-dimethylaminophenylsquaraine), were deposited on $SnO_2 $ electrodes by the Langmuir-Blodgett film technique. The DSSQ film exhibits ${\lambda}_{max}$ at ∼530 nm. The absorption is significantly red-shifted from the solution of DSSQ (633 nm in chloroform), suggesting that the squaraine chromophores form aggregates in the LB film. The photogeneration of the squaraine aggregates is studied by measuring the photocurrents in photoelectrochemical cells consisting of the squaraine of the aggregates is found to parallel its absorption spectrum and quantum efficiency as high as 0.3% has been observed. While the photocurrent was attenuated exponentially when stearic acid layers (up to 8 layers) are inserted between the squaraine layer and the electrode, it is nearly extinguished when the squaraine layer is over-coated with 2 layers of stearic acid. A model for the observation is proposed and the roles of the electrolytes and oxygen on the photogeneration process will be discussed.

• Journal of Sericultural and Entomological Science
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• v.43 no.2
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• pp.109-115
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• 2001

Silk sericin protein was extracted by treatment with enzyme or NaOH solution from raw silk and culled-cocoon shell. The extracted sericin was characterized and examined the functional properties as well as subjective properties for its use as a soap and a body cleaner. The optimum extraction conditions on specimen are NaOH (0.02 wt.%) or enzyme, Flavourzyme 3% under N2 gas. Molecular weights of sericin was decreased by treatment with enzyme, Actinase, from 10,000-30,000 to 2,700-4,200. Sericin showed important bioactive properties, for instance, lowering effect on blood glucose and alcohol. Subjective test of sericin soap and body cleaner showed superior in washability, foamability, and skin hydration, etc., to commercial soap and body cleaner. Therefore, it is thought that silk sericin can be expected as the source of bioactive and skin-compatible materials.

• Korean Journal of Microbiology
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• v.40 no.4
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• pp.275-281
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• 2004

Our previous research has demonstrated that the bacterium, Pseudomonas sp. NFQ-l capable of utilizing quin­oline (2,3-benzopyridine) as the sole source of carbon, nitrogen, and energy was isolated and characterized [Yoon et ai. (2003) Kor. J. Biotechnol. Bioeng. 18(3):174-179]. In this study, we have found that Pseudomonas sp. NFQ-l could degrade quinoline as well as benzoate, and extended this work to characterize the catechol 1,2­dioxygenase (C1,2O) purified from the bacterium cultured in benzoate media. Initially, C1,2O has been purified by ammonium sulfate precipitation, gel permeation chromatography, and Source 15Q. After Source 15Q, puri­fication fold was increased to approximately 14.21 unit/mg. Molecular weight of C1,2O was about 33 kDa. Physicochemical characteristics (e.g., substrate specificity, Km, Vmax, pH, temperature and effect of inhibitors) of purified C1,2O were examined. C1,2O demonstrated the activity for catechol, 4-methylcatechol and 3-meth­ylcatechol as a substrate, respectively. The Km and Vmax value of C1,2O for catechol was 38.54 ${\mu}M$ and $25.10\;{\mu}mol{\cdot}min^{-1}{\cdot}mg^{-1}.$ The optimal temperature of C1,2O was $30^{\circ}C$ and the optimal pH was approximately 8.5. Metal ions such as $Ag^+,\;Hg^+,\;Ca^{2+},\;and\;Cu^{2+}$ show the inhibitory effect on the activity of C1,2O. N-terminal amino sequence of C1,2O was analyzed as ^1TVKISQSASIQKFFEEA^{17}.$ In this work, we found that the amino acid sequence of NFQ-l showed the sequence homology of 82, 71, 59 and $53\%$ compared with C1,2O from Pseudomonas aeruginosa PA0l, Pseudomonas arvilla C-1., P. putida KT2440 and Pseudomonas sp. CA10, respectively.