• Microbiology and Biotechnology Letters
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• v.23 no.3
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• pp.255-262
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• 1995

Intact cells of Acinetobacter sp. T5-7 completely degraded trichloroethylene (TCE) following growth with phenol. This strain could grow on at least eleven aromatic compounds, e.g., benzaldehyde, benzene, benzoate, benzylalochol, catechol, caffeic acid, 2.4-D, p-hydroxybenzoate, phenol, protocatechuate and salicylate, and did grow on alkane, such as octane. But except phenol, other aromatic compounds did not induced TCE degradation. Phenol biotransformation products, catechol was identified in the culture media. However, catechol-induced cells did not degrade TCE. So we assumed that phenol hydroxylase was responsible for the degradation of TCE. The isolate T5-7 showed growth in MM2 medium containing sodium lactate and catechol rather than phenol, but did not display phenol hydroxyalse activity, suggesting induction of enzyme synthesis by phenol. Phenol hydroxylase activity was independent of added NADH and flavin adenine dinucleotide but was dependent on NADPH addition. Degradation of phenol produced catechols which are then cleaved by meta-fission. We identified catechol-2.3-dioxygenase by active staining of polyacrylamide gel.

• Journal of Microbiology and Biotechnology
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• v.5 no.4
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• pp.206-212
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• 1995

A strain BL-29, which produces a extracellular lytic enzyme on E. coli was isolated from the soil. The strain was identified as belonging to the genus Bacillus sp. The lytic enzyme was purified to homogeneity by ion exchange chromatography and gel filtration. Specific activity of the purified enzyme was 28, 850 U/mg protein and yield of the enzyme was 5$%$. The purified enzyme showed a single band on SDS-PAGE and its molecular weight was estimated to be 31, 000 by SDS-polyacrylamide gel electrophoresis and gel filtration column chromatography. The optimum temperature and pH were $55^{\circ}C$ and pH 10.0, respectively. The enzyme was stable at $45^{\circ}C$ but enzyme activity was reduced by up to 50$%$ when the temperature was raised to $55^{\circ}C$ for 15 min. Stable range of pH was from 5.0 to 11.0. but Enzyme activity was inhibited by lead-acetate, mercuric chloride, ethylene glycol-bis-[$\beta$-aminoethyl ether]-N, N, $N^1, $N^1$-tetraacetic acid (EGTA), and ethylenediamine tetraacetic acid (EDTA), but not affected considerably by treatment with other chemical reagents.

• Microbiology and Biotechnology Letters
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• v.18 no.4
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• pp.360-367
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• 1990

The several glycoside hydrolysing enzymes related to rutin degradation are found to be rhamnosidase, glucosidase and rutinosidase. Rutinosidase was purified to electrophoretic homogeneity from cell extracts of rutin-degrading strain, MT-57, which was identified as a Arthrobacter sp. Its molecular weight was estimated to be 42, 000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 40, 000 by gel filtration. The optimum pH for enzyme was found to be 7.5, and relatively stable in alkaline solution. The optimum temperature for enzyme was $45^{\circ}C$, being stable up to $50^{\circ}C$ for 20 min. The Bm value of enzyme for rutin was 0.5 $\mu \textrm m$. The enzyme activity was increased by the chelating agent such as EDTA, $NaN_3$, and 8-hydroxyquinoline, was strongly inhibited by $CO_{2+}, Ni^{2+}$, and $Cu^{2+}$. The enzyme had high substrate specificity in the rutinoside.

• Microbiology and Biotechnology Letters
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• v.18 no.1
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• pp.44-48
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• 1990

Alkalophilic sp. YC-335 isolated from soil was capable of producing large amount of cyclodextrin glycosyltransferase (CGTase) in culture broth. This enzyme was successively purified 52.9 folds with 17.8 yield by ethanol precipitation, DEAE-Toyopearl column chromatography and Sephadex G-100 column chromatography. The purified enzyme have a molecular weight of approximately 75,000 estimated by SDS polyaerylamide gel electrophoresis. The optimum pH and temperature for the enzyme activity were 6.0 and 5$0^{\circ}C$, respectively. The enzyme stable between pH 6 and 10, and up to 5$0^{\circ}C$. The thermostability of the enzyme was increased up to 6$0^{\circ}C$ by the addition of 15mM CaCl$_2$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.4
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• pp.587-593
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• 1995

Lectin was purified by using $(NH_4)_2SO_4$, DEAE-cellulose ion-exchange chromatography and Sephadex G-150 column chromatography from Alismatis Rhizoma(AR). The specific activity of AR lectin was 50, 441units/mg, and purification folds were 114. The AR lectin agglutinated human erythrocytes of all types(A, B, O, AB). The molecular weight of AR lectin was estimated about 90, 500 daltons by gel filtration and each subunits were 42,000, 27,000 and 22,500 daltons on SDS-PAGE respectively. The hemagglutinating activity of the lectin was inhibited by sialic acid, glucose, ribose, galactose, sucrose, and lactose. It was also inhibited by cations such as $Hg^{++},\;Fe^{++},\;Cu^{++}\;and\;Pb^{++}$.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.12
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• pp.1678-1682
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• 2001

The total proteins were estimated in both deoxycholate (DOC)-extract of sperm membrane and seminal plasma of chilled as well as frozen semen obtained from five Murrah buffalo bulls. Proteins were further characterized by polyacrylamide gel electrophoresis (PAGE) in three bulls. The protein content of sperm membrane extract (SME) and that of seminal plasma (SP) decreased gradually with increase in freezing period from 6 to 24 mo when compared with the values observed in freshly chilled semen in all bulls. The total decrease in protein content of SME and SP varied from 30-40% and 28-59% respectively during 6-24 mo of freezing. The number of glycoproteins/proteins (GP/P) in SME varied from 4-8 in freshly-chilled semen of all bulls and reduced to 2-4 after 24 mo of freezing. In SP, the number of proteins varied from 6-10 in freshly chilled semen of all bulls and reduced to 3-8 after 24 mo of freezing. Some of the proteins in SME and SP disappeared, others got altered and appeared with change in molecular weight after different freezing times. These studies reveal that alterations in the sperm membrane proteins may be responsible for damage to their membrane during freezing and thus lowering their fertilizability.

• Journal of Oral Medicine and Pain
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• v.17 no.2
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• pp.99-108
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• 1992

The purpose of this study was to evaluate the polymorphosms in parotid salivary proteins of the patients with diabetes mellitus. Saliva from the parotid glands was collected from 94 healthy Korean adults who were live in Kwang-ju and from 33 diabetes mellitus patients who had more than 140mg/dl of fastingblood sugar for one week. Diabetes mellitus patient group was subdivided to insulin dependent diatetes mellitus (IDDM) and non-insulin dependent diabetes mellitus (NIDDM). In the saliva collected from the parotid glands, parotid acidic protein(Pa), proline-rich protein(Pr) and double band protein(Db) were analyzed to evaluate the distribution of phenotype using alkaline slab polyacrylamide gel electrophoresis. The results were as follows : 1. The parotid acidic protein (Pa) was found more frequently in the diabetes mellitus patient group than in the control group, but the difference was not statistically significant. 2. The Pr(1-2) type was found more frequently in the control group, but the Pr(1-1) and Pr(2-2) type were found more freqnently in the diabetes mellitus patient group and the difference of phenotypic distribution was statistically significant between the two groups. (p<0.05) 3. The parotid acidic protein(Pa) and Pr(1-2) type were found more frequently in the noninsulin dependent diabetes mellitus (NIDDM) patients than in the insulin dependent diabetes mellitus patients, though the difference was not statistically significant.

• Journal of Oral Medicine and Pain
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• v.21 no.2
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• pp.317-329
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• 1996

Allelic frequency and genotype distribution of short tandem repeat(STR) F13A01 locus was analysed by polymerase chain reaction, polyacrylamide gel electrophoresis and silver staining from human genomic deoxyribonucleic acid(DNA) was extracted from 205 unrelated Korean to be applied to forensic identification and parentage testing as a database. The results were as follows : 1. 5 alleles and 11 genotypes of F13A01 locus were detected and heterozygosity value was 62.0% and the observed each alleles and allelic frequency was 3.2(0.363), 4(0.105), 5(0.063), 6(0.466), 16(0.002). 2. The allelic diversity value was 0.639 and the power of discrimination was 0.804.3. Compared with observed number of alleles and allele frequency in ethnic difference, result was appeared to be similar to that of Japanese and Asians, while was appeared to be much different to that of Blacks and Caucasians in the observed number of alleles and frequency of allele 3.2, 5, 7. From the above result of this investigation, the allelic frequency of STR F13A01 locus in the Korean was considerd to be useful for individual identification and parentage testing as a database.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.4
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• pp.1472-1480
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• 1996

The phenomena of drag reduction using small quantities of a linear macromolecules has attracted the attention of experimental investigations. It is well known that drag reduction in single phase liquid flow is affected by polymer materials, molecular weight, polymer concentration, pipe diameter and flow velocity. But the research on drag reduction in two phase flow has not intensively investigated. Drag reduction can be applied to phase change system such as chemical reactor, pool and boiling flow, and to flow with cavitation which occurs pump impellers. The purpose of the present work is to evaluate the drag reduction by measuring pressure drop, mean liquid velocity, and turbulent intensity and determine the effects of polymer additives on drag reduction in horizontal two phase flow. Experimental results show higher drag reduction using co-polymer comparing with using polyacrylamide. Mean liquid velocities increase as adding more polymer, and turbulent intensities decrease as the distance for the wall in inversed.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.4
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• pp.1501-1509
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• 1996

Differential pressure devices such as an orifice and Venturi are widely used in the measurement of flow rate of fluid mainly due to cost effectiveness and easy installation. In the current study, the viscoelastic effect on discharge and loss coefficients of those flow meters were investigated experimentally. Aqueous solutions of Polyacrylamide (200, 500, and 800 ppm) as viscoelastic fluids were used. Discharge coefficient of an orifice for viscoelastic fluids increased significantly up to approximately 15-20% when compared with that for water, while loss coefficient decreased up to 10-25% depending on the diameter ratio, .betha.. Also, pressure recovery for viscoelastic fluids was extended much longer than that for water. On the other hand, discharge and loss coefficients of Venturi for viscoelastic fluids were found to be strongly dependent on the Reynolds number. In both flow meters, the concentration effect for discharge and loss coefficients was not observed at more over than 200 ppm of aqueous solution. Conclusively, orifice and Venturi flow meters should be calibrated very carefully in the flow rate measurement for viscoelastic fluids.