Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal Basic Information
Journal DOI :
Korean Society for Biotechnology and Bioengineering
Editor in Chief :
Volume & Issues
Volume 9, Issue 5 - Dec 1994
Volume 9, Issue 4 - Oct 1994
Volume 9, Issue 3 - Sep 1994
Volume 9, Issue 2 - Jun 1994
Volume 9, Issue 1 - Mar 1994
Selecting the target year
Oxidation of Ethanol in the Gas Phase with Alcohol Oxidase and Alcohol Dehydrogenase
KSBB Journal, volume 9, issue 3, 1994, Pages 239~245
The effects of reaction temperature and the level of hydration(water activity) were studied for gas phase reactions of alcohol oxidase and alcohol dehydrogenase immobilized on DEAE-cellulose and controlled pore glass(CPG). Optimum reaction temperature zone of gas phase reaction was similar to that of aqueous phase reaction. The activity of alcohol oxidase increased dramatically and the stability decreased when the water activity was increased from 0.3 to 0.8. The apparent activation energies of the gas phase reaction decreased approaching the values obtained in the aqueous phase reaction as the water activity increased. In the both cases of alcohol oxidase and alcohol dehydrogenase, the rate constants of the gas phase reaction were lower than those of aqueous phase reaction by two orders of magnitude and these results could be correlated to the vapor-liquid equilibrium data of the substrate, ethanol.
Preparation of Aliphatic Polyester by Lipase Catalyzed Transesterificatoin in Anhydrous Organic Solvents
KSBB Journal, volume 9, issue 3, 1994, Pages 246~252
Enzyme-catalyzed polycondensatlon reaction of aliphatic polyesters with several repeating units was studied using the biocatalytic activities of lipases from different sources. Porcine pancreatic lipase (PPL) was found to be best in utilizing bls(2,2,2-trichloroethyl) glutarate and 1,4-butanediol as substrafes. The reaction was also catalyzed to some extent by the lipases from Humicola lanuginos and Psudomonas sp. In the series of short-chain diols(C2-C4), bis(2,2,2-trichloroethyl) glutarate was iransesterified fastest with 1,4-butanediol and for the long-chain diols (PEG-300-PEG-1000), the reaction was fastest with PEG-400. With PEGs, only monoesterification product was obtained. PPL functioned well in relatively hydrophilic organic solvents such as tetrahydrofuran(THF), ether and acetonitrile. The reaction rate was accelerated as the reaction temperature was raised from
while Mn values of the reaction products were not affected by the reaction temperature. End group analysis by NMR showed that Mn values of the polymer were in the range of 1500-4000 daltons.
Effect of Serum Type on Hybridoma Growth and Monoclonal Antibody Production
KSBB Journal, volume 9, issue 3, 1994, Pages 253~265
We have studied the effects of serum concentration and initial cell density on hybridoma cell growth and monoclonal antibody (MAb) production at various media supplemented with different types of serum. The types of serum were fetal bovine sera, newborn bovine calf sera, calf sera including supplemented calf sera, horse serum, and goat serum. The concentrations of each serum were 0.5, 1.25, 2.5, and 5% (v/v) and the inoculum densities were
cells/ml. The hybridoma cell growth and anti-Hepatitis B surface antigen (anti-HBsAg) MAb production were found to be enhanced by increasing the serum concentration and by increasing inoculum density regardless of serum type. We found that test sera purchased from different companies show different effects on cell growth and MAb production, although they are the same type of serum.
Reduction of Cell Membrane Toxicity of Amphotericin B Using Liposome System
KSBB Journal, volume 9, issue 3, 1994, Pages 266~271
Lipsome system composed of egg phosphatidylcholine was employed to reduce the membrane toxicity of Amphotericin B(Amp. B). Liposomal Amp. B, which showed a free drug equivalent antibiotic effect on fungi, displayed a remarkable reduction of toxicity of the drug against the membrane of red blood cell than that of fungizone which has been used in clinical treatment, and it shows conspicuously lowered toxicity on red blood cells. However liposomal Amp. B which contains cholesterol as a component of liposome lowered the antibiotic effect and toxicity than that phosphatidylcholine liposome. This due to the affinity between Amp. B and cholesterol. In addition to this,
-glucuronidase from snail juice crude enzyme reveals synergistic effect on liposomal Amp. B and free Amp. B. We also obtained positively raised antibiotic effect, when enzyme which is coupled with palmitic acid using NHSP inserted into liposome bilayer From these results, we suppose that the use of liposomal system in the case of Amp. B shows increasing antibiotic effect and dramatically lowered toxicity, thus, we think that we can solve the problem of Amp. B toxicity, which cause hesitate of clinical use.
Effect of Serum on Varicella-Zoster Virus Propagation
KSBB Journal, volume 9, issue 3, 1994, Pages 272~278
Attenuated varicella-zoster virus(VZV) was cultured in human embryonic lung cells. The effects of serum type and its concentration on the production of VZV were studied. Regardless of cell culture conditions, VZV yield was increased with multiplicity of infection, and the total cell concentration was decreased after virus infection. The newborn calf serum, calf serum, or horse serum was not as good as the fetal bovine serum or calf serum supplemented with iron for the propagation of VZV in the human embryonic lung cells. The yields of total VZV(cell-associated virus and cell-free virus) in the medium with calf serum containing iron were comparable to those in the medium supplemented with fetal bovine serum. Furthermore, some components of serum appear to be important for the maintenance of VZV infectivity.
Phosphoprotein Partitioning in Metal-Affinity Aqueous Two-Phase Systems and Prediction of Partitioning Behavior
KSBB Journal, volume 9, issue 3, 1994, Pages 279~286
A mathematical model has been derived and used to describe phosphoprotein partitioning in Fe(III) IDA-PEG/dextran two-phase systems. This model includes the inhibitory effects of hydrogen and hydroxyl ion concentrations on protein partitioning. For aqueous two-phase partitioning experiments, the Al and A2 subcomponents of ovalbumin carrying two and one surface phosphoryl group(s) were purified using an immobilized metal ion affinity chromatography (IMAC). The ratio of partition coefficients in the presence and absence of Fe(III)IDA-PEG, K/Ko, increased in the pH range of 3.0 to 5.0 due to deprotonation of the second oxygen of the phosphoryl group, and above pH 5.0 declined steeply by the inhibitory binding of hydroxyl ions to the metal ion. This partitioning behavior was well described by the mathematical model. The binding constants for formation of the complex between the phosphoryl group and the Fe(III)IDA-PEG were found to be
in the top and bottom phases, respectively. These values are 3-5 times those for interaction of Cu(II)IDA-PEG with a single surface-accessible histidine.
Effects of Cultivation Condition on Growth of the Hydrogen Sulfide-Degradating Thiobacillus sp. IW. Isolated from Waste Coal Mine Water
KSBB Journal, volume 9, issue 3, 1994, Pages 287~293
A bacterium isolated from waste coal mine water around Hawsun had an ability for the degradation of hydrogen sulfide. The isolate was identified as Thiobacillus sp. IW. on the basis of its morphological, physiological and chemotaxonomical characteristics. The optimum pH and temperature were 7 and
, respectively. Growth occurred in a pH range of 3 to 9. Due to the sulfate accumulated in liquid medium, the pH decreased. As a consequence the cell growth was inhibited. Potasium nitrate and glutamic acid were utilized as a nitrogen source but urea and ammonium chloride not consumed. Denitrification occurred in a basal medium containing the glucose but did not in a basal medium containing the malate. The maximum specific growth rate of cell was 0.78h-1 and generation time was 0.9 hour. The cell productivity was 6.25mg/1
h and the isolate grew logarithmically up to 18 hour. These results indicate that the isolate can be a suitable bacterium responsible for degradation of hydrogen sulfide as malodorous compounds.
Improved Recombinant ,
-Galactosidase Production Using Medium Additives at AcNPV Infection of Insect Cells in Batch and Continuous Two-Stage Bioreactors
KSBB Journal, volume 9, issue 3, 1994, Pages 294~298
The medium additives such as CaCl2, glucose, fructose, glutamine, glutamate and lipids were examined to enhance recombinant
-gal) production in batch and continuous two-stage bioreactor systems. The presence of each medium additive such as CaCl2, fructose, glutamate, cholesterol and tocopherol at AcNPV infection of Sf 21 cells had an effect on improved
-gal production. The recombinant
-gal production using the infection media supplemented with a mixture of 30mM
, 2.2mM fructose, 4.1mM glutamate and 0.34mM cholesterol was increased by about 40%.
Taxol Production in Taxus sap. Cell Cultures 1. Studies on Taxol Content in Yew Trees and Cultured Plant Cells
KSBB Journal, volume 9, issue 3, 1994, Pages 299~305
Taxol contents in various parts of 15 years old yew tree were determined. The descending order of taxol content per unit mass was stem bark, root bark, needle and seed. In the seed, that order was seed coat, embryo and endosperm. The total amount of taxol extractable from a 15 years old yew tree was 1.68 gram. This amount was distributed in needle, stem bark, root bark and seeds as 48.0, 23.8, 27.9 and 0.4%, respectively. Altitudinal variation of taxol content was also observed. More taxol was observed in yew trees grown at high altitude over 1000m above sea level. Calli and suspension cultures were induced from various yew trees. The presence of taxo] in cultured cells was established bv HPLC. The taxol content in cultured cells were different according to the source of explants. These results may be useful for the goal of large scale taxol production by cultured yew tree cells.
Optimization of the Optical Resolution of Racemic
-Methylbenzylamine Catalyzed by Enzymatic Reaction in Organic Media
KSBB Journal, volume 9, issue 3, 1994, Pages 306~311
Optical resolution of racemic
-methylbenzylamine was carried out by using Bacillus licheniformis protease in organic media. Enantioselective amidation of racemic amino with an ester as an acyl donor was successfully employed to resolve the racemate. To enhance reaction rate and enantioselectivity, pH-adjustment by lyophilization of enzyme dissolved in buffer, colyophilization with salts or lyoprotectants, selection of solvents and molecular design of esters were investigated. The optimization of the resolution reaction achieved about 30-fold increase in initial reaction rate and about 12-fold increase in enantioselectivity, respectively.
The Esterification of Acetyltyrosine by
-Chymotrypsin in EtOH/Water Mixture
KSBB Journal, volume 9, issue 3, 1994, Pages 312~318
The esterification of Ac-Tyr-OH was carried out in one-phase system containing ethanol by
-chymotrypsin. The results of the esterification reaction are as follows. Chitin-
-chymotrypsin complex was found to be an effective catalyst for the esterlfication of Ac-Tyr-OH in ethanol organic solvent. The optimal conditions for the esterification were chitn/
-chymotrypsin ratio, 20(w/w); reaction temp.,
; reaction pH, 8.0; reaction time, 24 hrs. Also, addition of chitin in water/water-miscible organic solvent was effective for the stability of the enzyme. The esterification yield, Km and Vmax under optimal conditions were 93%, 3.093mM and 1.088mM/mg/hr, respectively.
The Studies for the Malate Tissue Biosensor Using Malate Dehydrogenase(Decarboxylating) in the Bundle Sheath Cell of the Corn Leaf
KSBB Journal, volume 9, issue 3, 1994, Pages 319~324
A biosensor for the measurement of malate has been constructed by the sodium-alginate immobilized bundle sheath cell tissue of corn leaf containing malate dehydrogenase (decarboxylating) (EC 1. 1. 1. 40) on the CO2 gas-sensing electrode. The proposed tissue sensor had the linear in the range of malate concentration
with a slope of 53.5 mV/decade in 0.02M Tris-HCl buffer solution at optimum pH 8.0, and
. A response time was 16∼18min. The present L-malate sensing tissue sensor is stable for more than one week. At pH 7.4, Km value was
. The various kinds of salt did not effect the signal of malate tissue biosensor as the inhibitor. We can measure the malate by the CO2 electrode at the pH=8.0. Thus, the proposed tissue sensor will be useful for the measurement of malate.
Effect of Micelles on the Reaction of RuBPCase in Maize Leaf
KSBB Journal, volume 9, issue 3, 1994, Pages 325~331
PGA is formed in a route of CO2 fixation of RuBP catalyzed by RuBPCase, followed by reduction of the PGA by NADH to GAP This reduction is enhanced in an anionic micellar solution(SDS), in which NADH is distributed in the aqueous and the micellar pseudophases in a given ratio. This micellar bounded NADH reacts to PGA, and in higher micellar concentration than
, most of NADH is oxidized to NAD+ by PGA. On the other hand, in the solutions of the positive ionic(CTABr), zwitter ionic(Chaps) and nonionic (Brij and Triton X-100) micelles, the reactions are also enhanced and the concentrations of NADH reach minima with micellar concentrations. Such minima are typical of micellar catalyzed bimolecular reactions, and the fall in concentrations of the reductant followed by a gradual increase is charataristic of reactions of hydrophobic substrates: that is, the reductions of PGA by NADH are sharply enhanced in a range of the lower micellar concentrations, and NADH amounts in ca.
micellar solutions are reached to minima, followed by gradual increases of the reductant concentration.
Reversed Micellar Protein Extraction in a Hollow Fiber Membrane Extractor
KSBB Journal, volume 9, issue 3, 1994, Pages 332~338
Solubilization phenomena of a protein in a reversed micellar solution were investigated and a hollow fiber membrane extractor was tested for reversed micellar protein extraction equipment. Alkaline protease was used as a model protein compound and the reversed micellar solution was consisted of AOT and isooctane. It was found that protein solubilization was strongly influenced by ionic strength and pH. The distribution coefficient of the protease between the aqueous solution and the AOT/isooctane solution was also observed to be as high as 4.0 within the scope of this experiment. A hollow fiber membrane extractor was constructed and tested for the protein extraction. The overall mass transfer coefficient at a typical experimental condition of this study was observed to be
. It was also found that the mass transfer resistance on reversed micellar solution was the dominant resistance for the protein transfer.
Effects of Glucose Repression and Plasmid Copy Number on Cloned Gene Expression in Recombinant Yeast
KSBB Journal, volume 9, issue 3, 1994, Pages 339~345
Deletions between UASG and the GALI TATA box reduced glucose repression and allowed constitutive expression of the gene product in the absence of galactose. The relative inducer level (ratio of galactose/glucose concentrations) affected the extent of gene expression and glucose repression. Glucose repression was reduced by a factor of 2 to 5 as the relative inducer level increased. In the medium containing galactose only, induction of
-galactosidase synthesis by galactose increased with plasmid copy number. On the contrary, plasmid copy number did not affect significantly
-galactosidase synthesis in the medium containing both glucose and galactose (2% glucose＋2% galactose), which might be due to glucose repression caused by high glucose concentration. However, when the medium contained the relatively high inducer level (0.4% glucose＋0.8% galactose),
-galactosidase synthesis increased with plasmid copy number, indicating that the beneficial effect of higher galactose concentration was weaker than the repressive effect of higher glucose concentration.