• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.441-447
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• 1998

A bacterial strain No. 43 was isolated from soil samples as a levan-assimiating microorganism producing an extracellular levanase and hydrolying levan to levanbiose. According to the taxonomic characteristics of its morphological and physiological properties, the strain was idenified as Pseudomonas sp. No. 43. The optimum culura medium was composed of 10g levan, 5g(NH4)2SO4, 3g NH4Cl, 3g polypepton, 1g K2HPO4, 0.5gMgSO4.7H2O, and 0.2g MnCl2.4H2O per liter. The cultivation for levanase was carried out in pH 7.0 at 4$0^{\circ}C$ for 28hr. The reaction product was a kind of oligosaccharide and it was purified by chilled ethanol precipitation and gel filtration for evalluation of degree of polymerization (DP). The purified product was determined as levanbiose of MW 342 and DP2 by HPLC and FAB-MS.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.4
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• pp.267-272
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• 2007

Various kinds of RI wastes are discharged from licensed organizations of radioisotopes les such as hospitals and clinic organizations, educational organizations, research institutions, and public organizations. Radioiodines such as $^{125}I\;and\;^{131}I$ are radioisotopes mainly used in nuclear medicine and industry. A method for the determination of radioiodines in RI wastes has been applied to measure low level activity using acid decomposition method and HPGe gamma ray spectrometer. Prior to analysis of real samples, $^{131}I$ reference solution and 10 g of yellow tissue paper was added to flask in mantle and was heated in 100 mL of 0.4 N $K_2Cr_2O_7$ and 100 mL of 9 M $H_2SO_4$, and then distilled after adding 10 mL of 30% $H_2PO_3$ and 1 mL of 30% $H_2O_2$. The condensed iodine by circulator was extracted into $CCl_4$, then back-extracted into the aqueous phase with 10 mL of 5% $K_2SO_2$ solution. Finally, $^{131}I$ was measured at 364.48 keV using HPGe gamma ray spectrometer after precipitation and filtration. Chemical yield of three steps such as acid decomposition process, chemical separation process, and precipitation and filtration process was more han 94% respectively, MDA(Minimum Detectable Activity) of $^{131}I$ at this analytical condition was 0.6 Bq/g.

• Pediatric Infection and Vaccine
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• v.4 no.1
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• pp.73-78
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• 1997

Purpose : Escherichia coli O157 can produce diarrhea as well as hemorrhagic colitis and hemolytic uremic syndrome. In many parts of North America, E. coli O157 often is the second or third most commonly isolated enteric bacterial pathogens. Recently, intakes of fast food, including hamburgers have increased in Korea. Therefore, E. coli O157 infection in Korea are likely to be increased. Methods : Stool samples from 317 pediatric diarrheal patients were analyzed by culture on sorbitol-MacConkey agar. Sorbitol-negative colonies were teated by E. coli O157 latex agglutination test. Results : Of the 317 specimens, one (0.3%) were E. coli O157:NM that not produced Shiga toxin. The 7 year old male patient who had complained of abdominal pain, vomiting and non-bloody diarrhea for 2 days. The patient was improved for 2 days after admission. Conclusions 1 Only one (0.3%) of all fecal samples were isolated E. coli O157 that not produced Shiga toxin. Therefore, routine stool culture for the isolation of E. coli O157 was not likely to be neccessary so far.

• Microbiology and Biotechnology Letters
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• v.20 no.4
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• pp.395-400
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• 1992

A novel strain of HSL613 producing a large amount of cholesterol oxidase as an extra~ cellular enzyme was isolated from soil samples. Experiments were carried out to optimize the condition of cholesterol oxidase production using HSL613 strain. This microorganism was shown to give the maximum yield f)f cholesterol oxidase in the medium containing 2% glucose, 2% yeast extract, 0.2% $K_2HP0_4$, 0.1% NaCl. 0.005% $CaCl_22H_2O, 0.001% $FeSO_47H_20$. The optimum temperature was $30^{\circ}C$ and the enzyme production reached a maximum level at 144 hours of cultivation (10.3$\mu$/ml).

• Microbiology and Biotechnology Letters
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• v.9 no.2
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• pp.51-57
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• 1981

1,2-propanediol-utilizing yeast, Y-1-4, was isolated from sludge sample by the enrichment culture technique. The product produced from 1,2-propanediol by the selected strain was identified as lactic acid by paper chromatography and infrared absorption spectrum. The strain assimilated ethanol, 1,2-propanediol, glycerine and glucose, but it produced lactic acid from 1,2-propanediol used as the sole carbon source. Under optimal conditions, the strain Y-1-4 was cultured with shaking at 3$0^{\circ}C$ for 4days in the medium containing 1,2-propanediol 20.0g, NH$_4$Cl 5.0g, KH$_2$PO$_4$ 1.0g, MgSO$_4$.7$H_2O$ 0.5g, FeSO$_4$.7$H_2O$ 0.25g, yeast extract 0.4g, CaCO$_3$ 3. 0g and tap water to one liter, and then the yield of lactic acid was about 12. 1g per liter of the culture broth.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.619-623
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• 1989

The cultural condition of Pseudomonas mendocina for polysaccharide production was examined. The optimal medium contains following composition per liter of distilled water: Sucrose 23.75g, $(NH_4)_2SO_4$ 1.57g, Yeast extract 0.5g, $KH_2PO_4\;2.9g,\;MgSO_4.\;7H_2O\;1.0g,\;CaCO_3$ 2.5g. The optimum temperature and pH were $30^{\circ}C$ and 6.5. At the condition. Ps mendocina produced 5.98g/l of polysaccharide. The culture viscosity after 3 days was 191mPa.s at $70sec^{-1}$. The product yield $(Y_{p/s})$ and specific productivity $(Q_p)$ were 25.18% and 32.83mg/g-cell/h.

• Applied Biological Chemistry
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• v.35 no.3
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• pp.173-178
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• 1992

A bacterium having CMCase activity was isolated form soil and identifed as a Pseudomonas sp YD-15. The optimum conditions for the production of CMCase were avicel 1.2%, yeast extract 0.5%, $KNO_3$ 0.06%, $K_2HPO_4$ 0.2%, $MgSO_4$ $7H_2O$ 0.15%, pH 8.0, $30^{\circ}C$ and 60 hours cultivation. The CMCase was purified 15.2 folds with 14ft yield through ammonium sulfate precipitation, DEAE-sepharose column chromatography and sephadex G-100 gel filtration chromatography. The optimum pH and temperature for the enzyme activity were 6.0 and $50^{\circ}C$, respectively. The enzyme was stable between pH 5.0 and 8.0, below $50^{\circ}C$. The molecular weight was calculated about 100,000 by SDS-polyacrylamide gel electrophoresis. $K_m$ value for CMC used as a substrate was 40 mg/ml.

• Microbiology and Biotechnology Letters
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• v.23 no.3
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• pp.263-268
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• 1995

A screening was performed to isolate exoploysaccharide-producing microorganisms, which synthesized specific exopolysaccharide for the substitutive of commercial polysaccharides, from natural sources. Soil bacterium, one of 378 mucoid isolates, was finally selected as potential producer of polysaccharides which made the culture broth very viscous and thus examined in detail for optimal medium composition. Isolated strain was identified as Xanthomonas sp. EPS- 1 from the results of morphological and biochemical characteristics. The composition of optimal medium for exopolysaccharide production was as follows: 50 g sucrose, 1.5 g peptone, 2 g KH$_{2}$PO$_{4}$, 2 g MgSO$_{4}$, -7H$_{2}$O, 3 g NaCl, 0.05 g CaCO$_{3}$, 0.07 g FeSO$_{4}$-7H$_{2}$O and 0.05 g MnSO$_{4}$-7H$_{2}$O in 1 liter of distilled water. From the experiments of temperature and pH dependence, the optimal conditions for exopolysaccharide biosynthesis seemed to be 30$\circ$C and 8.0, respectively. About 14.9 gram of maximum exopolysaccharide per liter was obtained at the initial pH 8.0, 30$\circ$C and 250 rpm in a flask culture. The exopolysaccharide EPS-1 had such potential as an emulsifying agent and a gelling agent in comparision with commercial exopolysaccharide.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.1028-1032
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• 1997

The strain No. 33, which produces cellulose-degrading enzyme, was isolated from soil. Yellow halo was identified when the culture supernatant of the strain was loaded onto agar plate containing 2.0% CMC using paper disc method. From scanning electron microscopic observation, the morphology of the stain was rod-shaped. For identification, several biochemical characteristics were tested, and this strain was identified to Bacillus sp. So, we named this strain as Bacillus sp. No. 33. The maximal growth was observed when the stain was cultured in the medium containing 1.0% glucose, 3.0% yeast extract, 0.5% $KH_2PO_4$, 0.02% $MgSO_4{\cdot}7H_2O$, pH 7.0 at $30^{\circ}C$ for 39 hours with shaking. The maximal enzyme production was accomplished using the medium containing 4.0% CMC, 2.0% yeast extract, 0.5% $KH_2PO_4$, 0.04% $MgSO_4{\cdot}7H_2O$, pH 7.0 at $30^{\circ}C$ for 42 hours with shaking.

• Korean Journal of Environmental Biology
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• v.19 no.1
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• pp.87-92
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• 2001

For the biological treatment of industrial wastewater containing high concentration of phenol, isolation and characterization of phenol - degrading bacterium were carried out. A bacterial strain P2 capable of degrading phenol was isolated from contaminated soils by enrichment culture technique and identified as the genus Rhodococcus by morphological, cultural, biochemical characteristics, and Biolog system. The optimal medium composition and cultural conditions for the growth and degradation of phenol by Rhodococcus sp. P2 were 0.1% of (NH$_4$)$_2$SO$_4$, 0.2% of KH$_2$PO$_4$, 0.25% of Na$_2$HPO$_4$ㆍ12$H_2O$, 0.2% of MgSO$_4$ㆍ7$H_2O$, and 0.008% of CaC1$_2$ㆍ2$H_2O$ along with initial pH 8.5 at 3$0^{\circ}C$. Rhodococcus sp. P2 could grow with phenol as the sole carbon source up to 1,800 ppm in batch cultures, but did not grow in medium containing above 2,000 ppm of phenol. When 800 ppm phenol was given in the optimal media, Rhodococcus sp. P2 completely degraded it within 24 h. Meanwhile, 1,800 ppm of phenol was degraded within 9 days. Rhodococcus sp. P2 could utilize toluene, n-hexane, xylene and benzene as sole carbon source .