• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.309-313
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• 1997

Bench scale Sikhyes were produced from rice and glutinous rice and limit dextrins in rice Sikhye and glutinous rice Sikhye were purified by ethanol precipitation and Biogel P-2 gel chromatography and FPLC on Superose 12 column and analyzed. The purified limit dextrin in rice Sikhye and glutinous rice Sikhye showed bot signal of $\alpha$-1,4- and $\alpha$-1,6-glucosidic linkage with its estimation ratio of 4.5:1 and 5.9:1, respectively, by 1H-NMR analysis. Limit dextrins were hydrolyzed by pullulanase. The enzyme hydrolysis products contained maltose, maltotriose, maltotetraose, maltopentaose and matohexaose. These results suggest that limit dextrins were composed of these maltoolgosaccharide series with $\alpha$-1,6-glucosidic bond.

• Microbiology and Biotechnology Letters
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• v.26 no.5
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• pp.420-426
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• 1998

An extracellular glutamyl aminopeptidase (EC 3.4.11.7) producing bacterium was isolated from soil and identified as Bacillus licheniformis based on its morphological and physiological characteristics. The aminopeptidase was purified to homogeneity by ammonium sulfate precipitation, Phenyl Sepharose, Resource Q, and Superose 12 column chromatographies. The specific activity of the purified aminopeptidase was 9.2 unit/mg for glutamyl p-nitroanilide with 17.6 purification folds. The purified aminopeptidase had an estimated molecular mass of 64 kDa consists of two different subunits (42 kDa and 22 kDa), and its isoeletric point was 5.2 measured by isoelectric focusing. The optimum pH and temperature of the aminopeptidase were 8.0 and 55$^{\circ}C$, respectively. The aminopeptidase was inhibited by EDTA and 1,10-phenanthroline, suggesting it be a metalloenzyme. Comparing with other aminopeptidase, the enzyme showed relatively high activity against peptide having glutamic acid as N-terminal.

• Microbiology and Biotechnology Letters
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• v.26 no.5
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• pp.379-386
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• 1998

Deterioration of food is in general caused by the presence of microorganisms and chemical compounds of food itself. There exists antimicrobial compound in the food, however, addition of food antiseptics, additives, or physico-chemical processing is a common practice. The safety of artificial chemical antiseptics became a serious public concern, therefore, new natural antiseptic compounds are in need to be developed. We have isolated a new natural antifungal protein (KBS-B2) from Astragal seed through ammonium sulfate precipitation and column chromatography using FPLC Mono-S and Superose 12HR. The purified protein inhibited growth of Candida albicans, and spore germination of food spoiling fungi such as Aspergillus ochraceus, Penicillium expensum, P. digitatum and Botrytis cineria. Antifungal effect of the KBS-B2 protein could be directly assayed by bioautography overlaying the fungal spores on the electrophoresed acrylamide gel. The comparison of N-terminal amino acid sequences of the KBS-B2 with known antifungal protein revealed that had 50% homology to thaumatin and zeamatin like proteins.

• KSBB Journal
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• v.15 no.2
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• pp.145-149
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• 2000

Methyl mercaptan oxidase was isolated and purified from Thiobacillus thiooxidans KCTC2505 for the detection of mercaptans. T The produre of purification involved DEAE-Sephacel and Superose 12 column chromatographies with recovery yields of 40 a and 6.3%, and specific activity of 19.7 and 80.1 units/mg-protein, respectively. The molecular weight of purified methyl m mercaptan oxidase was determined to be 68.1 kDa by SDS-PAGE. The extract from DEAE-Sephacel column chromatography h had a high activity in oxidizing methyl mercaptan to produce formaldehyde which can be easily detected by purpald-coloring m method. Optimum temperature for activity was observed at $43^{\circ}C$. This enzyme was activated by $NH_4CI and (NH_4)_2S0_4$, and | inhibited by KCI and NaC!.

• Fisheries and Aquatic Sciences
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• v.9 no.3
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• pp.115-117
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• 2006

A micro algal growth-enhancing polysaccharide compound was isolated from the green alga Monostroma nitidum using water extraction, molecular fractionation, a DEAE-cellulose column, and fast protein liquid chromatography using a Superose-12 column. The yield of the compound from the seaweed powder was 8.3$\times$l0$^{-3}$%. At 2 mg/mL concentration, the polysaccharide enhanced Tetraselmis suecica cell growth in f/2 medium by approximately 160%.

• The Korean Journal of Zoology
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• v.37 no.4
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• pp.524-530
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• 1994

An Arpase complex has been purified to apparent homogeniety from the extract of chick skeletal muscle using conventional column chromatographies and glycerol density gradient centrifugation. This eWe has a sedimentation coefficient of 15S as determined by the gradient centrifugation and therefore is referred to as the 15S ATPase. It behaves as a 600-kOa molecule upon gel filtration analysis using a Superose-6 column. However, the ATPase runs as a 95-kDa polvpeptide when analyzed by polvacrvlamide gel electrophoresis in the presence of sodium dodecyl sulfate. Thus, the Arpase is likely to consist of six identical subunits of 95 KDa. It has a Km value of 0.6 mM for ATP and is maximally active at pH 9.

• Transactions of the Korean hydrogen and new energy society
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• v.19 no.2
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• pp.124-131
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• 2008

Crude cytoplasmic fraction of phototrophic purple sulfur bacterium, Thiocapsa roseopersicina NCIB 8347, were initially prepared and purified by sonication, ultracentrifugation, ammonium sulfate fractionation and heat-treatment and it has been previously reported. Using various applications of chromatography far the purification of membrane-bound and soluble hydrogenases from heat-treated enzyme fraction were studied at present report. When the heat-treated enzyme preparation was applied to the anion column chromatography using Q-sepharose, Fraction I and II, which were extracted with the KCl 0-0.5 M gradient, showed the specific evolution hydrogenase activity 3.86 and 2.27 U/mg-protein respectively. Specific hydrogenase activitys of Fraction I and II were further increased to 4.35 and 7.46 U/mg-protein for Fraction I and to 2.49 and 4.41 U/mg-protein fur Fraction II respectively, when hydrophobic interaction column, Phenyl superose, and anion exchange column, Mono-Q, were applied. Size exclusion chromatography using superdex 200 concentrated the hydrogenase Fraction I and II to 9.19 and 7.84 U/mg-protein respectively at the final step of purification.

• Applied Biological Chemistry
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• v.36 no.2
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• pp.86-92
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• 1993

Myrosinase from radish was purified by DEAE Bio-Gel, Con-A, and Superose-6 column. The purified myrosinase(II) possessed 2 subunits, and their molecular as determined by SDS-polyacrylamide gel electrophoresis were 53 and 39 KD, respectively. The specific activity of purified enzyme was 37,500 units/mg. The enzyme was purified approximately 44-fold compared to the crude enzyme. Optimum pH of the myrosinase was $6.5{\sim}7.0$ in phosphate and Tris-HCl buffer solutions. Optimum temperature of the enzyme was $37{\sim}38^{\circ}C$. The enzyme was stable at pH 7.0, and less than $30^{\circ}C$. Cu or Hg ion significantly inhibited the enzyme activity, but ascorbic acid enhanced, resulting in a maximum activity by 1 mM ascorbic acid. Among the ascorbic acid analogues, dehydroascorbic acid did not affect, whereas others showed a little effect, but less than ascorbic acid itself. Individual 2-mercaptoethanol and dithiothreitol (reducing agents) did not enhance the enzyme activity. but 2-mercaptoethanol effect was enhanced when mixed with ascorbic acid.

• Journal of Photoscience
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• v.9 no.2
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• pp.388-390
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• 2002

Two ferredoxin (Fd) fractions, namely, Fd-A and Fd-B were isolated from Heliobacillus mobilis cells, and purified by ammonium sulfate fractionation, DEAE, gel-permeation and Phenyl-Superose column chromatographies under anaerobic conditions. Their absorption spectra were typical of 2[4Fe-4S] cluster type Fds with peaks at about 385 and 280 nm and a shoulder at about 305 nm. Their N-terminal amino acid sequences were determined, which showed that both of them contain a [4Fe-4S] cluster binding motif. Fd-B was sensitive to oxygen, and itsA$_{385}$ value decreased by about 50% in 2 h at 4$^{\circ}C$ under aerobic conditions. In contrast, $A_{385}$ of Fd-A was essentially unchanged up to 24 h under the same conditions.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.6
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• pp.728-735
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• 1995

The peptidyl prolyl cis-trans isomerase(PPlase, EC 5.2.2.8) from Bacillus stearothermophilus SIC1 was extracted from the cells treated with by lysozyme. PPlase was purified from the cell extracts by heat treatment, ammonium sulfate precipitation, ion exchange chromatography and finally gel filtration (FPLC). The purity of purified the enzyme after Superose 12 column chromatography was examined by sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE). The molecular weight of the purified PPlase was estimated as 18,000 by SDS-PAGE. The 39 amino acid residues from the N-terminus were determined by the protein sequencer. The enzyme showed the optimum pH at 8.0 and was stable at the range of pH 7.0 to 8.0. The enzyme was considerably stable after heat treatment at $60^{\circ}C$ for 30 minutes, and the enzyme was quite stable up to $65^{\circ}C$. The presence of the PPlase in the refolding solution accelerated the isomerization rate of the assay peptide.