• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.4
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• pp.563-569
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• 1995

Myrosinase from Korean cabbage(Bogdoli) was purified and its enzymatic properties were investigated. Myrosinase from the Korean cabbage was purified by DEAE Bio-Gel Sepharose, Concanavalin-A, and Mono-Q column chromatography and exhibited a 55KD molecular weight with a single band on the gel of SDS-PAGE. The enzyme was purified about 21-fold compared to its crude enzyme and a specific activity of purified enzyme was 15, 120units/mg. Optimum pH of the myrosinase was 7.0 in both phosphate and Tris-HCl buffer solutions, the enzyme was stable at pH 6.5~7.0. Optimum temperature of enzyme was 37~38$^{\circ}C$. The enzyme activity was significantly inhibited by Cu2+ and Hg2+, but enhanced by ascorbic acid, resulting in a maximum activity at 1mM ascorbic acid. Among the ascorbic acid analogues, dehydro-ascorbic acid did not affect, whereas others showed a little effect on the enzyme activity, but less than ascorbic acid itself. Reducing agents such as 2-mercaptoethanol and dithiothreitol had no effect on the enzyme activity, but the enzyme activity was enhanced when 2-mercaptoethanol was mixed with ascorbic acid.

• Journal of Plant Biotechnology
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• v.4 no.1
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• pp.39-44
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• 2002

The fast-migrating cationic peroxidase isozyme, named RC3, was purified from rice (Oryza sativa cv. Nak-Dong) callus. Purification of the enzyme was accomplished by ammonium sulfate fractionation, CM-cellulose ionexchange chromatography, and Sephacryl S-100 gel filtration. The molecular mass of the enzyme was about 34 KDa as determined by SDS-PACE and 38 KDa by Sephacryl-100 gel filtration. The pI value of the enzyme was 8.9. Antiserum against RC3 was raised in rabbits, and anti RC3 antiserum reacted with RC3 isozyme by Ouchterlony double immunodiffusion. The optimum pHs and Km values of the enzyme for various substrates were determined. Kinetic studies with various substrates showed that RC3 had very low Km value of 0.01 mM for ferulic acid and ascorbic acid. However, the enzyme did not use esculetin as a substrate.

• Journal of Microbiology and Biotechnology
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• v.10 no.3
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• pp.307-311
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• 2000

Abstract Extracellular chitinase was purified from the culture liquid of the marine bacterium, Bacillus sp. LJ-25 , and its enzymatic properties were examined. The purified chitinase exhibited a single band on SDS-PAGE and the molecular weight was estimated to be approximately 50 kDa. The optimum pH and temperature for the enzymatic activity were 7.0 and $35^{\circ}C$, respectively. The activity of the chitinase was strongly inhibited by $Zn^{2+}$ and slightly inhibited by $Ba^{2+},{\;}Co^{2+},{\;}Mn^{2+},{\;}and{\;}Cu^{2+}$. The purified chitinase did not hydrolyze $p-nitrophenolN-acetyl-{\bata}-D-glucosaminide{\;}(GlcNAc)_2$ and Micrococcus lysodeikticus cells, which are known to be the substrates for exo-type chitinase. Among the hydrolyzates of colloidal chitin, $(GlcNAc)_2$ was in the highest concentration with small amounts of GlcNAc and $(GlcNAc)_3$..

• BMB Reports
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• v.44 no.1
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• pp.64-69
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• 2011

A peroxidase (PD-cP; 0.47 mg/100 g leaves) was purified from autumn leaves of Phytolacca dioica L. and characterized. PD-cP was obtained by acid precipitation followed by gel-filtration and cation exchange chromatography. Amino acid composition and N-terminal sequence of PD-cP up to residue 15 were similar to that of Spinacia oleracea (N-terminal pairwise comparison showing four amino acid differences). PD-cP showed a molecular mass of approx. 36 kDa by SDS-PAGE, pH and temperature optima at 3.0 and $50.0^{\circ}C$, respectively and seasonal variation. The Michaelis-Menten constant ($K_M$) for $H_2O_2$ was 5.27 mM, and the velocity maximum ($V_{max}$) $1.31\;nmol\;min^{-1}$, while the enzyme turnover was $0.148\;s^{-1}$. Finally, the presence of $Ca^{2+}$ and $Mg^{2+}$ enhanced the PD-cP activity, with $Mg^{2+}$ 1.4-fold more effective than $Ca^{2+}$.

• Journal of Microbiology and Biotechnology
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• v.22 no.10
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• pp.1381-1387
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• 2012

We applied enzymatic hydrolysis and tangential flow filtration (TFF) to purify a novel anticancer peptide from Mytilus coruscus (M. coruscus) and investigated its anticancer properties. To prepare the peptide, eight proteases were employed for enzymatic hydrolysis. Pepsin hydrolysates, which showed clearly superior cytotoxic activity on prostate cancer cells, were further purified using a flow filtration system using a TFF and consecutive chromatographic methods. Finally, a novel anticancer peptide was obtained, and the sequence was identified as Ala-Phe-Asn-Ile-His-Asn-Arg-Asn-Leu-Leu. The peptide from M. coruscus effectively induced cell death on prostate, breast and lung cancer cells but not on normal liver cells. This is the first report of an anticancer peptide derived from the hydrolysates of M. coruscus.

• Proceedings of the Korean Society of Life Science Conference
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• 2003.10a
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• pp.90-90
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• 2003

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.4
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• pp.687-694
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• 1996

Myrosinase was purified from Korean mustard seed(Brassica juncea) by a sequential process of DEAE-cellulose, concanavalin A-sepharose, and Superose 6 chromatography. The molecular weight of puri-fied myrosinase(II-2) determined by SDS-polyacrylamide electrophoresis was 67KD. About a 248-fold purification for myrosinase II-2 was obtained after Superose 6 chromatography. Optimum pH of the myrosinase was 7.0 and optimum temperature of the enzyme was $3^{\circ}C.$ The enzyme was stable at pH 7.0, and below $30^{\circ}C.$ Cu, Hg and Fe ion significantly inhibited the enzyme activity, but ascorbic acid enhanced, resulting in a maximum activity by 1mM ascorbic acid. Among tile ascorbic acid ana-logues, dehydroascorbic acid inhibited the enzyme activity, whereas others showed a little effect. Reducing agents such as 2-mercaptoethanol and dithiothreitol inhibited the enzyme activity, but the reducing agents with ascorbic acid was enhanced enzyme activity.

• Journal of Life Science
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• v.8 no.3
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• pp.326-332
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• 1998

Cyclodextrin glucanotransferase from B. stearothermophilus KJ16 that can produce both cyclodextrin glucanotransferase and cyclodextrinase was purified by ammonium sulfate precipitation, DEAE-cellulose chromatography, Sephadex G-100 chromatography, and FPLC. The molecular weight of the purifice enzyme was about 65,000 dalton by SDS-PAGE. The optimal pH and temperature were 6.0 and $60^{\circ}C$, respectively. The enzyme was stable at $50^{\circ}C$ for 1 hr and in the pH range of 5.5 and 8.5. Mercaptoethanol and dithiothreitol inhibited the enzyme activity strongly. The enzyme produced 60% cyclodextrin(CD) from 5% soluble starch with the $^{\alpha}$, $^{\beta}$, $^{\gamma}$-CD ratio of 42:46:12. Amylopectin was the most suitable substrate with 67% conversion to CD.

• BMB Reports
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• v.38 no.2
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• pp.232-237
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• 2005

A glutathione S-transferase (GST) from Lactuca sativa was purified to electrophoretic homogeneity approximately 403-fold with a 9.6% activity yield by DEAE-Sephacel and glutathione (GSH)-Sepharose column chromatography. The molecular weight of the enzyme was determined to be approximately 23,000 by SDS-polyacrylamide gel electrophoresis and 48,000 by gel chromatography, indicating a homodimeric structure. The activity of the enzyme was significantly inhibited by S-hexylGSH and S-(2,4-dinitrophenyl) glutathione. The enzyme displayed activity towards 1-chloro-2,4-dinitrobenzene, a general GST substrate and high activities towards ethacrynic acid. It also exhibited glutathione peroxidase activity toward cumene hydroperoxide.

• Microbiology and Biotechnology Letters
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• v.17 no.4
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• pp.370-378
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• 1989

An Alkalophilic Bacillus circulans that can produce significant amount of cyclodextrin glucanotransferase (CGTase) was newly isolated from soil. The culture filtrate was successively purified by ($NH_4$)$_2$$SO_4$precipitation, DEAE-Sephadex column chromatography, and Sephadex G-100 column chromatography. The enzymatic properties, including molecular weight, optimal pH and temperature, stability, and kinetic parameters, were determined. The cyclodextrin synthesis reaction catalized by the purified CGTase was also studied. The sweet potato and corn starch were found to be the most suitable substrates with 60% conversion to cyclodextrin. The highest conversion was achieved at the CGTase concentration of 900-1,100 units/g of soluble starch. The purified CGTase could also catalize the transglycosylation on stevioside.