• Proceedings of the PSK Conference
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• 2003.04a
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• pp.217.3-218
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• 2003

A novel lectin has been purified from the fruiting bodies of the mushroom, Fomitella fraxinea, which belongs to bracket fungi by a combination of ion-exchange chromatography on DEAE-cellulose and gel filtration chromatography on Sephacryl S-200 HR. The lectin, designated as FFrL, was a homotetrametric protein with a molecular weight of 50 kDa as demonstrated by SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) and MALDI-TOF-MS(matrix assisted UV laser desorption/ionization time-of flight mass spectrometry). (omitted)

• Journal of Ginseng Research
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• v.37 no.1
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• pp.117-123
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• 2013

Polyphenol oxidase (PPO) was purified from fresh ginseng roots using acetone precipitation, carboxymethyl (CM)-Sepharose chromatography, and phenyl-Sepharose chromatography. Two isoenzymes (PPO 1 and PPO 2) were separated using an ion-exchange column with CM-Sepharose. PPO 1 was purified up to 13.2-fold with a 22.6% yield. PPO 2 bound to CM-Sepharose, eluted with NaCl, and was purified up to 22.5-fold with a 17.4% yield. PPO 2 was further chromatographed on phenyl-Sepharose. The molecular weight of the purified PPO 2 from fresh ginseng was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and was about 40 kDa. The optimum temperature and pH were $20^{\circ}C$ and 7.0, respectively, using catechol as a substrate. Pyrogallol showed the highest substrate specificity. The effect of a PPO inhibitor showed that its activity increased slightly in the presence of a low concentration of citric acid. High concentrations of acidic compounds and sulfite agents significantly inhibited purified ginseng PPO 2.

• Korean Journal of Microbiology
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• v.25 no.2
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• pp.148-156
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• 1987

Extracellular laccase (E.C. 1.10.3.2) from the culture filtrate of Pleurotus ostreatus was purified by ammonium sulfate precipctation, protamine sulfate precipitation, DEAE-Sephadex A-50 ion exchange chromatography and Sephadex G-100 gel permeation chromatography. The molecular weight of the enzyme was estimated by SDS-polyacrylamide gel electrophoresis to be 58,000 and the isoelectric point was 3.75. The optimum temperature for the enzyme was about $45^{\circ}C$ and the optimum pH was 6.5. The enzyme was found to be stable at temperature below $35^{\circ}C$ and rapidly inactivated at higher temperatures. Km values for ferulic acid, vanillic acid, dihydroxyphenylalanine (DOPA) were 48.6.$\mu$M, 0.52mM, and 2.73mM, respectively, which indicates that the enzyme has much higher affinity towards ferulic acid. The reaction products of the enzyme were separated by TLC and HPLC.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.638-639
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• 2000

Quinone reductase was purified to electrophoretic homogeneity from bovine liver by using ammonium sulfate fractionation, ion-exchange chromatography, and gel filtration chromatography. The enzyme utilized either NADH or NADPH as the electron donor. The optimum pH of the enzyme was pH 8.5, and the activity of the enzyme was greatly inhibited by $Cu^{2+}$ and $Hg^{2+}$ ions, dicumarol and cibacron blue 3GA. The enzyme catalyzed the reduction of several quinones and other artificial electron acceptors. Furthermore, the enzyme catalyzed NAD(P)H-dependent reduction of azobenzene or 4-nitroso-N,N-dimethylaniline. The apparent $K_m$ for 1,4-benzoquinone, azobenzene, and 4-nitroso-N,N-dimethylaniline was 1.64mM, 0.524mM and 0.225mM, respectively. The reduction of azobenzene or 4-nitroso-N,N-dimethylaniline by quinone reductase was strongly inhibited by dicumarol or cibacron blue 3GA, potent inhibitors of quinone reductase.

• YAKHAK HOEJI
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• v.37 no.5
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• pp.490-498
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• 1993

To find antitumor components in the hot water extract from the basidiocarps of Hypsizigus mamomus. protein-bound polysaccharides were purified and fractionated by DEAE-cellulose ion exchange column chromatography and Sepharose CL-4B gel filtration chromatography. When a dose of 20 mg/kg/day was injected intraperitoneally into ICR mice. fraction IV of the component showed the highest inhibition ratio of 73.8% against the count of hemolytic plaque forming cells in mice to 3.2 times. when IV was about 30 KD and the fraction was composed of 76.1% polysaccharide and 4.9% protein. The hexosamine was detected in all the fractions, showing that the polysaccharide and protein moieties were bound each other.

• Journal of Dairy Science and Biotechnology
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• v.15 no.1
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• pp.21-26
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• 1997

Lactobacillus acidophilus 223, 606, and NCFM-F among 21 isolated from fecal contents of humans demonstrated inhibitory activity attributed to bacteriocin(s). The bacteriocin(s) were heat stable and nondialyzable proteinous compounds and exhibited narrow inhibitory spectra of activity. Neither hydrogen peroxide nor pH were responsible for inhibitory action. All of the producer strains were resistant to their own bacteriocin(s). The bacteriocin(s) were purified by ammonium sulfate precipitation, gel chromatography and ion exchange chromatography for further characterization. The bacteriocin(s) of human origin exhibited similar characteristics.

• 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.

• Food Science and Biotechnology
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• v.14 no.5
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• pp.581-585
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• 2005

The antimicrobial activity of partially purified enterocin K25, produced by Enterococcus sp. K25, was abolished by proteases such as pepsin and proteinase K. The bacteriocin was resistant to heat treatment at $75^{\circ}C$ for 15 min and lost 75% of its activity at $100^{\circ}C$ for 30 min. Enterocin K25 showed bactericidal mode of action against an indicator strain, Lactobacillus plantarum NCDO 955. Enterocin K25 was purified to 112.6-fold purity via conventional steps of ammonium sulfate precipitation, ion exchange chromatography, and reversed phase high performance liquid chromatography (RP-HPLC). The molecular mass of the purified enterocin K25 was estimated as 4.3 kDa on an electrophoresis gel. Plasmid (${\sim}6.5\;kb$) linkage of production of enterocin K25 was confirmed by plasmid curing.

• Journal of Microbiology
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• v.34 no.1
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• pp.82-89
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• 1996

Purine nucleoside phosphorylase (PNP) was purified in Micrococcus luteus (M. luteus) using streptomycin sulfate and amomonium sulfate fractionation, three times by a Sephadex G-100 gel filtration and a DEAE-Sephadex A-50 ion exchange chromatography. The enzyme was purified 72 folds with a 11% recovery and showed a single band in a nondenaturing gel electrophoresis. The M. W. of PNP turned out to be 1.35 * 10$^{5}$ delton in G-150 gel filtration chromatography. The stability of the enzyme was increased by treatment with both substrates, MgCI$_{2}$ or CaCI$_{2}$, but not significantly kcal/mol. M. luteus PNP catalyzed the phosphorolysis of inosine, deoxyinosine, guanosine and deoxyguanosine with the Km value of 1.5 * 10$^{-3}$ M, 3.0 * 10$^{-3}$ M, 5.0 * 10$^{-4}$ M, respectively. The enzyme was reacted with adenosine, 1-methylnosine and 1-methylguanosine as substrates, which were shown to be poor substrates for mammalian enzyme.

• Korean journal of food and cookery science
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• v.18 no.1
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• pp.94-100
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• 2002

The dietary carbohydrates are mainly digested and adsorbed at small intestine. We developed a new food additive as an egg yolk antibody(1gY) against maltase, sucrase and sodium dependent g1ucose cotransporter(SGLT) for the regulation of blood glucose level and weight control. The maltase, sucrase and SGLT were purified from porcine small intestine which is very similar to that of human in physiological characteristics. The purification step contained an ultracentrifugation, ion exchange chromatography and hydrophobic chromatography. The hens were immunized by purified protein and the IgY activities against immunized antigens were determined. This antibody obtained from the immunized hen's egg yolks directly inhibited the activities of maltase and sucrase in vitro. And the IgY delayed and decreased the increment of blood g1ucose level after administration of maltose, sucrose and glucose in rat about 30 to 60%. The results of this study suggest that the IgY inhibiting the carbohydrate digestion could be used as functional food materials for weight control and regulation of blood glucose level in diabetes.