• Korean Journal of Food Science and Technology
• /
• v.5 no.2
• /
• pp.78-83
• /
• 1973

The naringin hydrolyzing enzyme has been purified from the culture filtrate of the mold Aspergillus S-1 which selected to remove the bitter test of the orange or citrus fruits industrily. In a view of purity naringinase was more effectively purified in order of molecular sieving on Sephadeex G-200, starach gel electrophoresis, chromatography or a DEAE-Cellulose column and fractional precipitation by ammonium sulfate. The purified enzyme is homogeneous in paper electrophoresis from a culture filtrate by treatment fractional precipitation with ammonium sulfate, DEAE-Cellulose treatment and Sephadex-200 column chromatography and it hydrolyse only naringin to purunin.

• Journal of Microbiology and Biotechnology
• /
• v.14 no.2
• /
• pp.268-275
• /
• 2004

To investigate the potential application of the single-cell gel electrophoresis (SCGE) assay to carp as an aquatic pollution monitoring technique, gill, liver, and blood cells were isolated from carp exposed to a direct-acting mutagen, N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), or indirect mutagen, $benzo[\alpha]pyrene$ $(B[\alpha]P)$, then the DNA strand breakage was analyzed using the assay. Based on testing 5 different cell isolation methods and 6 electrophoretic conditions, the optimized assay conditions were found to be cell isolation by filter pressing and electrophoresis at a lower voltage and longer running time (at 0.4 V/cm for 40 min). In preliminary experiments, gill and liver cells isolated from carp exposed to MNNG in vitro exhibited DNA damage signals even with 0.5 ppb exposure, which is a much higher dose than previously reported. In the gill cells isolated from carp exposed to 0.01-0.5 ppm MNNG in vivo, significant dose-and time-dependent increases were observed in the tail for 4 days. As such, the linear correlation between the relative damage index (RDI) values and time for each dose based on the initial 48-h exposure appeared to provide effective criteria for the genotoxicity monitoring of direct-acting mutagenic pollution. In contrast, the in vivo exposure of carp to 0.25-1.0 ppm of $B[\alpha]P$ for 7 days resulted in dose-and time-dependent responses in the liver cells, in which 24-h delayed responses for metabolizing activation and gradual repair after 48 h were also observed. Thus, the negative-sloped linear correlation between the RDI and time at each dose based on the initial 48 h appeared to provide more effective criteria for the genotoxicity monitoring of indirect mutagenic pollution.

• Proceedings of the Korean Society of Fisheries Technology Conference
• /
• 2002.05a
• /
• pp.195-196
• /
• 2002

• The Korean Journal of Mycology
• /
• v.16 no.2
• /
• pp.101-105
• /
• 1988

• Bulletin of Food Technology
• /
• v.22 no.3
• /
• pp.502-512
• /
• 2009

• Proceedings of the PSK Conference
• /
• 2003.10b
• /
• pp.230.3-231
• /
• 2003

The therapeutic use of protein pharmaceuticals produced by recombinant DNA technology is increasing in recent decades. In order to investigate the quality of recombinant proteins, it is important to identify and assign the impurities produced in the process of recombination or in storage conditions. Capillary Electrophoresis is emerging technology exhibiting high sensitivity, selectivity and speed and may be most powerful tools for this application. In this study, human growth hormone (hGH) has been analyzed by various mode of capillary electrophoresis such as capillary zone electrophoresis (CZE), capillary gel electrophoresis (CGE), and capillary isoelectric focusing (cIEF) to indicate the chemically or biologically oriented variants and the degraded fragments. (omitted)

• Applied Biological Chemistry
• /
• v.27 no.2
• /
• pp.73-78
• /
• 1984

The optimum culture time and initial pH, for the production of exo-maltotetraohydrolase from Pseudomonas stutzeri IAM 12097, in the trypticase medium were 36 hrs and pH 6.3, respectively. Exo-maltotetraohydrolase was purified by $(NH_4)_{2}SO_4$ and two times of column chromatography on DEAE-cellulose. Specific activity of the purified enzyme was 108.6U/mg protein and yield of the enzyme activity was 9.4%. The purified enzyme showed a single band on polyacrylamide gel electrophoresis and SDS-polyacrylamide gel electrophoresis.

• Microbiology and Biotechnology Letters
• /
• v.27 no.4
• /
• pp.298-303
• /
• 1999

An $\alpha$-D-galactosidase ($\alpha$-D-galactoside galactohydrolase, EC 3. 2. 1. 22) from earthworm was purified by affinity chromatography using N-$\varepsilon$-aminocaproyl-$\alpha$-D-galactopyranosylamine coupled to sepharose and its properties were examined. The specific activity of the purified enzyme, tested with p-nitrophenyl-$\alpha$-D-galactopyranoside as substrate, was 314 units/mg protein, representing an 122-fold purification of the original crude extract. The final preparation obtained from by Sephadex G-25 chromatography showed a single band on SDS-polyacrylamide gel electrophoresis. The molecular weight was determined to be 48,000 by SDS-polyacrylamide gel electrophoresis. The purified galactosidase was showed maximum activity at pH 4.5 and 4$0^{\circ}C$, and was stable in the pH and temperature ranges from 4.0 to 5.5 and 30 to 5$0^{\circ}C$, respectively. The enzyme activity was inhibited by Zn2+, Hg2+ and Co2+. When the purified $\alpha$-galactosidase treated to guar gum for 6 hour, gel-promoting property was increased. It was clear that enzymatic elimination of galactose from guar gum by purified $\alpha$-galactosidase would lead to a significant increase in gelation ability.

• Journal of Microbiology and Biotechnology
• /
• v.1 no.2
• /
• pp.102-110
• /
• 1991

Alkalophilic Bacillus sp. YJ-451, which was isolated from soil at several area in Korea, produced a novel type of bacteriolytic enzyme (cell wall peptidoglycan hydrolase) extracellulary. The cell wall hydrolytic activity was identified as a clear zone on sodium dodecyl sulfate polyacrylamide gel electrophoresis containing 0.2% (w/v) cell wall of Bacillus sp. as substrate. This enzyme was successively purified 66 fold with 3.2% yield in culture broth by ammonium sulfate precipitation, CM-cellulose column chromatography, and gel filtration, followed by hydroxylapatite column chromatography. The molecular weight of the purified enzyme was estimated to be 27,000 by sodium dodecyl sulfate polyacrylamide gel electrophoresis and gel filtration column chromatography. The optimum pH and temperature for the activity of the enzyme were pH 10.0 and $50^{\circ}C$, respectively. The enzyme was stable between pH 5.0 and 10.0 and up to $40^{\circ}C$. Among the microorganisms used in this experiment the enzyme was active against most of gram negative strains and the genus Bacillus such as B. megaterium, B. licheniformis, B. circulans, B. pumilus, B. macerans, B. polymyxa. The release of dinitrophenylglutamic acid but not reducing group from cell wall peptidoglycan digested by the enzyme suggested that the enzyme is a kind of peptidase which hydrolyzes the peptide bond at the amino group of D-glutamic acid in the peptidoglycan.

• Korean Journal of Food Science and Technology
• /
• v.18 no.4
• /
• pp.288-293
• /
• 1986

A raw starch-digesting enzyme from Rhizopus oryzae was purified by ammonium sulfate fractionation, DEAE-sephacel column chromatography and Sephadex G-150 gel filtration. The specific activity of purified enzyme was 45.2 Ulmg protein and the yield was 16.2%. The purified enzyme was found to be homogeneous bypolyacrylamide gel electrophoresis and its molecular weight was estimated to be 67,000 by SDS-polyacrylamide gel electrophoresis, and also the enzyme had Km value of 4.082 mg/ml for raw corn starch. The optimal temperature and pH for the enzyme activity were $50^{\circ}C$ and 4.0-5.0, respectively. Reaction product of raw corn starch by purified enzyme was glucose mainly.