• YAKHAK HOEJI
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• v.31 no.2
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• pp.92-97
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• 1987

The N-[1H-6-fluoro-1,4-dihydro-4-oxo-7-chloroquinoline-3-carboxy] succinimide was reacted with amoxicillin, ampicillin and 6-APA to give 6-[D-(-)-$\alpha$-{1H-6-fluoro-1,4-dihydro-4-oxo-7-chloroguinoline-3-carboxamido} p-hydroxyphanyl acetamido] penicillanic acid [1], 6-[D-(-)-$\alpha$-{1H-6-fluoro-1,4-dihydro-4-oxo-7-chloroquinoline-3-carboxamido} phenylacetamido] penicillanic acid [10] and 6-[1H-6-fluoro-1,4-dihydro-4-oxo-7-chloroquinoline-3-carboxamido] penicillanic acid [19]. The 1-alkyl-6-fluoro-1,4-dihydro-4-oxo-7-substituted quinoline-3-carboxylic acids were reacted with ethyl chloroformate for making mixed anhydride; these mixed anhydrides were reacted with amoxicillin, ampilcillin and 6-APA to give 6-[D-(-)-$\alpha$-{1-alkyl-6-fluoro-1,4-dihydro-4-oxo-7-substituted quinoline-3-carboxamido} p-hydroxyphenylacetamido] penicillanic acid [2-9], 6-[D-(1)-$\alpha$-{1-alkyl-6-fluoro-1,4-dihydro-4-oxo-7-substituted quinoline-3-carboxamido} phenylacetamidod penicillanic acid [11-18] and 6-[1-alkyl-6-fluoro-1,4-dihydro-4-oxo-7-substituted quinoline-3-carboxamido] penicillanic acid [20-27].

• Korean Journal of Environmental Biology
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• v.23 no.2 s.58
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• pp.173-183
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• 2005

The ichthyofauna and community structure in the Chuncheon Reservoir, Korea, were investigated from August 2003 to April 2004. The total number of fish caught from the period was 10,821 fish representing 41 species and 13 families. There were 16 Korean endemic species, including Hemibarbus mylodon, Acheilognathus yamatsutae and Odontobutis platycephala. Dominant species was Hypomesus olidus $(30.69\%) $ and subdominant species was Hemibarbus labeo $(14.70\%)$. Also, Zacco platypus $(10.57\%)$, Zacco temminckii $(9.66\%)$, Micropterus salmoides$(4.81\%)$, Rhinogobeus brunneus $(4.28\%)$ and Microphysogobio yaluensis $(3.10\%)$ were numerous. The biomass of collected fishes were Hemibarbus labeo (34.63 kg), Hypomesus olidus (19.01 kg), Cyprinus carpio (12.77 kg), Opsariichthys uncirostris amurensis (11.28 kg), Zacco platypus (8.04 kg). Among the 7 introduced fishes in Chuncheon Reservoir Carassius cuvieri, Hypophthalmichthys molitrix and Micropterus salmoides were originated from foreign countries, and others (Anguilla japonica, Hypomesus olidus, Oncorhynchus masou mason and Chaenogobius urotaenius) were introduced from other native river systems.

• Korean journal of applied entomology
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• v.31 no.4
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• pp.486-491
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• 1992

The aboveground activities of the larger black chafer (Holotrichia morosa Waterhouse) and the Korean black chafer (H. diomphalia Bates) adults were investigated in the field and laboratory from 1991 through 1992. In a field cage, H. morosa adults emerged from the ground between 7 : 40-9 : 00 p.m. and H. diomphalia adults emerged between 7 : 30-10 : 00 p.m. After emergence, both females and males flied actively for less than one minute in H. morosa, while males flied inactively and females did not fly at all in H. diomphalia. Once emerged, adults of the two species mated or fed on plant leaves and seemed to stay aboveground till dawn. H. mOTOsa adults were attracted to a blacklight trap mainly between 8 : 10-10 : 00 p.m. in the field. H. morosa males and females emerged from soil every other day in a glass cistern.

• Analytical Science and Technology
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• v.19 no.3
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• pp.203-210
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• 2006

The determination of trace selenium in milk powder has been studied by octopole reaction cell(ORC)-ICP-MS. The interferences by polyatomic ions and other concomitant molecular species could be removed remarkably by using $H_2$ as reaction gas in ORC. Compared to the normal mode (no cell gas), the $H_2$ cell gas mode improved the accuracy and precision. The quantitative result was average 102.7% and it was slightly higher than certified standard value of milk powder and the RSD was 7.6%.

• Applied Microscopy
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• v.51
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• pp.17.1-17.10
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• 2021

Our previous study on the binding activity between Cel5H and clay minerals showed highest binding efficiency among other cellulase enzymes cloned. Here, based on previous studies, we hypothesized that the positive amino acids on the surface of Cel5H protein may play an important role in binding to clay surfaces. To examine this, protein sequences of Bacillus licheniformis Cel5H (BlCel5H) and Paenibacillus polymyxa Cel5A (PpCel5A) were analyzed and then selected amino acids were mutated. These mutated proteins were investigated for binding activity and force measurement via atomic force microscopy (AFM). A total of seven amino acids which are only present in BlCel5H but not in PpCel5A were selected for mutational studies and the positive residues which are present in both were omitted. Of the seven selected surface lysine residues, only three mutants K196A(M2), K54A(M3) and K157T(M4) showed 12%, 7% and 8% less clay mineral binding ability, respectively compared with wild-type. The probable reason why other mutants did not show altered binding efficiency might be due to relative location of amino acids on the protein surface. Meanwhile, measurement of adhesion forces on mica sheets showed a well-defined maximum at 69±19 pN for wild-type, 58±19 pN for M2, 53±19 pN for M3, and 49±19 pN for M4 proteins. Hence, our results demonstrated that relative location of surface amino acids of Cel5H protein especially positive charged amino acids are important in the process of clay mineral-protein binding interaction through electrostatic exchange of charges.

• Bulletin of the Korean Chemical Society
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• v.19 no.11
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• pp.1244-1248
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• 1998

Ozonolysis reactions of cyclic olefins 1a-c and norbomene In in the presence of trifluoroactophenone 6 provided the corresponding cross-ozonides 7a-c and 7n. Further reactions of ozonides 7a-c and 7n with the independently prepared carbonyl oxide 11 gave diozonides of structure l0a-c and 10n. The ozonolysis of 1methylcyclopentene 12a and 1-methylcyclohexene 12b in the presence of trifluoroactophenone 6 provided exclusively ozonide 15 and 16 derived from capture of carbonyl oxide 13. All of the new ozonides have been isolated as pure substances and characterized by their 1H NMR and 13C NMR spectra.

• Journal of environmental and Sanitary engineering
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• v.19 no.4 s.54
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• pp.69-75
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• 2004

The inhibitory effect of the food processing agent on growth of Escherichia coli O157:H7, Salmonella Enteritidis, and Listeria monocytogenes was performed with hydrogen peroxide and lactic acid, and combination of hydrogen peroxide and lactic acid. The minimun inhibitory concentration (MIC) of hydrogen peroxide in E coli O157:H7 was 100 ppm at pH 5.0, 6.0, 6.5 and 7.0, while in Listeria monocytogenes 25 ppm at PH 5.5, 6.0 and 50 ppm at PH 6.5, 75ppm at pH 7.0. MIC of lactic acid in E coli O157:H7 was 2500 ppm at pH 5.0, 6.0, 6.5 and 7.0. MIC of lactic acid in S. Enteritidis was 1250 ppm at pH 5.0, 2500 ppm at pH 5.5, 6.0, 5.5 and 7.0, while in L monocytogenes 625 ppm at pH 5.5 and 125 ppm at pH 6.0, 6.5 and 7.0. MIC of combined hydrogen Peroxide and lactic acid in E. coli O157:H7, S. Enteritidis, and L. monocytogenes was 75 ppm of hydrogen peroxide with 2500 ppm of lactic acid at pH 6.5. The correlations between MICs of hydrogen peroxide and lactic acid in E. coli O157:H7, S. Enteritidis and L. monocytogene were obtained through the coefficient of $determination(R^2)$. $R^2$ value were 0.9994, 0.9935 and 0.9283, respectively. The inhibitory effect of hydrogen peroxide and lactic acid in E. coli O157:H7, S. Enteritidis and L. monocytogenes could be confirmed from the result of this experiment. Therefore, it was expected that the food process would increase or maintain by using lactic acid together with hydrogen peroxide.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.2
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• pp.212-218
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• 2006

Changes of paralytic shellfish poison (PSP) contents, toxicity and toxin composition with pH and storing periods at different temperature in toxic blue mussel, Mytilus edulis, were tested by using fluorometric HPLC method. Toxicity at pH 3 was the highest as 14.1 MU/g $(100\%)$ and showed 12.9 MU/g $(92.1\%)$ at pH 5, 9.0 MU/g $(63.8\%)$ at pH 7, 3.6 MU/g $(25.5\%)$ at pH 9 and 0.8 MU/g $(5.7\%)$ at pH 10 which suggested PSP was unstable at alkaline conditions. The decrease in toxicity during storage days was depend on pH and temperature. The toxicity markedly decreased until during the first S day storage $(19.9\~65.3\%)$ at all pH (3, 5, 7, 9) and temperature (30, 5, $-20^{\circ}C$), but, slightly decreased after then till to 30 days. C group toxin (C1 and C2) was the major components and other toxins such as GTX 1,2,3,4, STX and dcSTX were detected. Among the 8 toxins, GTX1,4, dcSTX and STX were firstly decreased according to the decreasing the toxicity at all processing conditions. The toxicity in blue mussel (14.1 MU/g) were able to remove by heating over 10 minutes at pH higher than 7.

• Korean Journal of Animal Reproduction
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• v.7 no.1
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• pp.19-23
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• 1983

Present studies were conducted to investigate the developmental stage and the location of embryos in the reproductive tract at various times after ovulation, the morphologically normal after thawing of embryos preserved in liquid nitrogen, and the survival after transferring frozen-thawed embryos. The results obtained were as follows: 1. Embryo stage and location in the reproductive tract after hCG administration. For the investigation of embryo stage and location in the reproductive tract after ovulation, rabbits were laparotomized at 24, 40, 48, 72 and 120 hrs post hCG injection, simultaneously with mating. the oviducts and uteri were flushed out with PBS medium containing 50% rabbit serum, respectively. 1) Most of embryos was remained in the oviduct within 48 hrs, with the lapse of time, embryos were started to move to uterus and shifted in uterus at 72 hrs after hCG injection. 2) The representatives of embryos stage collected at 24, 40, 48, 72 and 120 hrs were 1-cell(60.4%), 8-cell to early morula (52.3, 39.3%), late blastocyst (95.5%) stages, respectively. 2. Morphological normality and survival of the frozen-thawed embryos. For the evalution of the quality and viability on the frozen-thawed embryos, immediately after thawing, embryos were assessed by morphologically normal under a dissecting microscope, and a further test of frozen-thawed embryos was made by transferring the morphologically normal embryos to the uteri of recipient rabbit induced pseudopregnancy by the injection of hCG at the time of hCG injection in donor rabbits. 1) The propotions of embryos which a, pp.ared morphologically normal was higher when 8-cell (85.7%) and morula(90.5%) were used for freezing than when 4-cell (66.7%) and blastocyst (75.8%) were used. 2) Preganacies were observed at Day 15 after transfer of frozen-thawed 8-cell (7/13), morula (19/42) and blastocyst (3/19) but not after transfer of embryos at 4-cell stage.

• Korean Journal of Microbiology
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• v.39 no.1
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• pp.51-55
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• 2003

To develop environment-friendly biofertilizer solubilizing insoluble phosphates, a bacterium possessing a high ability to solubilize $Ca_{3}(PO_{4})_{2}$) was isolated from the rhizosphere of peas. On the basis of its morphological, cultural, physiological characteristics, and Vitek analysis, this bacterium was identified as Pantoea agglomerans. The optimal medium composition and cultural conditions for the solubilization of insoluble phosphate by P. agglomerans R-38 were 3% of glucose.0.1% of TEX>$NH_{4}NO_{3}$, 0.02% of $MgSO_{4}\cdot\7H_{2}O$, and 0.06% of $CaCl_{2}\cdot\2H_{2}O$ along with initial pH 7.5 at $30^{\circ}C$. The highest soluble phosphate production under optimum condition was 898 mg/L after 5 days of cultivation. The solubilization of insoluble phosphate was associated with a drop in the pH of the culture medium. The strain produced soluble phosphate to the culture broth with the concentrations of 698 mg/L against CaHPO$_4$, 912 mg/L against hydroxyapatite, 28 mg/L against $FePO_{4}\cdot\4H_{2}O$, and 19 mg/L against $AIPO_{4}$, respectively.