• Korean journal of food and cookery science
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• v.26 no.1
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• pp.104-109
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• 2010

Korean Chinese cabbage (Brassica campestris L. ssp. pekinensis) is one of the major cruciferous vegetables. Cruciferous vegetables contain a series of relatively unique secondary metabolites of amino acids called glucosinolates. Although glucosinolates do not appear to be bioactive, they are hydrolyzed by plant myrosinase when the cells in plants are damaged, and release biologically active compounds such as isothiocyanates, nitriles, and thiocyanates. The objective of this study was to determine the myrosinase activity and total glucosinolate levels of Korean Chinese cabbages by different salting times (0, 12, 18, and 24 h) and salt concentrations (6, 10, 14%). The total water content, salt content, and pH of brined cabbages decreased with increasing salting time. The myrosinase activity as determined by a glucose kit, decreased with increasing salting time and salt content. The total glucosinolates were purified using an anion exchange column and measured by UV-visible spectrophotometer. The fresh Korean Chinese cabbages contained $25.38{\pm}1.45\;{\mu}mol/g$ dry weight of glucosinolates. However, the total glucosinolates of brined cabbages decreased with increasing salting time and salt concentration. After 24 h of salting time, the total glucosinolates of brined cabbages rapidly decreased by $16.12{\pm}11.09$, $11.25{\pm}10.91$, $9.29{\pm}10.73\;{\mu}mol/g$ in 6%, 10%, and 14% salt solution, respectively. Overall, the total glucosinolate levels of Korean Chinese cabbages were found to vary inversely with salting time and salt concentration.

• Journal of Applied Biological Chemistry
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• v.52 no.4
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• pp.157-162
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• 2009

An agar-liquefying bacteria (SC-22), which produces a diffusible agarase that caused agar softening around the colony was isolated from Daecheong lake in Korea. Chemotaxanomic and phylogenetic analyses based on 16S rRNA gene sequences revealed the strain was classified as Cellvibrio mixtus SC-22. The isolate SC-22 showed maximal extracellular agarase activity with 58.5 U/mL after 48 h cultivation in the presence of 0.2% agar. It was observed that the isolate produced two kinds of extracellular and three kinds of intracellular isoenzymes. The major agarase was purified from the culture filtrate of agarolytic bacteria by ammonium sulfate precipitation, anion exchange and gel filtration column chromatographic methods. The molecular mass of the purified enzyme was estimated to be 25 kDa by SDS-PAGE. The optimum pH and temperature of the purified enzyme were pH 7.0 and $50^{\circ}C$, respectively. The agarase activity was activated by $Fe^{2+}$, $Na^+$ and $Ca^{2+}$ ions while it was inhibited by $Hg^{2+}$, $Mn^{2+}$ and $Cu^{2+}$ at 1 mM concentration. The predominant hydrolysis product of agarose by the enzyme was galactose and disaccharide on TLC, indicating the cleavage of $\beta$-1,4 linkage in a random manner. The enzyme showed high substrate specificity for only agar and agarose among various polysaccharides.

• Journal of the Korean Chemical Society
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• v.25 no.5
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• pp.306-310
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• 1981

Induced circular dichroism spectra of racemic cobalt(III) complexes for $[Co(en)_3]^{3+},\;[Co(tn_)3]^{3+},\;cis-[Co(NH_3)(en)_2]^{3+},\;[Co({\beta}-ala)(en)2_]^{2+},\;[Co(gly)(en)_2]^{2+}\;and\;[Co(acac)(en)_2]^{2+}$ were measured when they were dissolved in aqueous d-tartrate2- solution at room temperature. Only a single negative CD spectrum was observed for all the complexes above in visible region(400∼500nm). It was interpreted that these CD bands were attributed to the difference in interaction between ${\Lambda}$-and ${\Delta}$-enantiomers with d-tartrate$^{2-}$. Namely, when d-tartrate$^{2-}$ was added to ${\Lambda}$-enantiomer and ${\Delta}$-enantiomer, it caused ${\Lambda}$-enantiomer to change greatly and ${\Delta}$-enantiomer to change only slightly; combined the results proved induced circular dichroism. The enantiomer for which the eluent has a stronger affinity should be eluted faster in ion-exchange column chromatography. It is possible to predict the elution order of chromatography from the sign of the induced CD if stronger interaction of chiral anion with the complex leads to greater change in the natural CD spectrum of the complex. The elution order was in complete agreement with the prediction from the sign of the induced CD spectrum for all the measured complexes.

• Journal of Dairy Science and Biotechnology
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• v.15 no.1
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• pp.33-44
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• 1997

We investigated the immunological function of cheese whey protein concentrate (CWPC), which is a by-product of cheese production, using mitogenic activity in murine splenocytes as an index. A fraction isolated by gel filtration and anion exchange chromatography of CWPC showed high mitogenic activity, comparable to the activity of lipopolysaccharide (LPS). The fraction was detected as a single band on SDS-PAGE. It contained calcium, inorganic phosphorus, and carbo-hydrate, indicating the active component to be a glycophosphopeptide (GPP) Since pronase digestion of GPP did not reduce its mitogenic activity, carbohydrate rather than peptide may be important in the activity, When applied on an anti-${\beta}$-caseinophosphopeptide (${\beta}$-CPP ) antibody affinity column, the GPP was separated into two components, one with affinity to ${\beta}$-CPP and the other without such affinity. Both the components contained N-linked oligosaccharide chains and had the mitogenic activity. These results demonstrate that cheese whey contains a GPP having strong mitogenic activity

• Korean Journal of Agricultural Science
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• v.22 no.1
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• pp.82-95
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• 1995

These experiments were carried out to isolate SIgA from human and bovine milk. The immunochemical properties of SIgA from human and bovine milk were examined by Gel filtration, DEAE and SDS-PAGE. Double Immunodiffusion, and Immunoelectrophoresis. The results obtained are as follows: 1. Human SIgA was purified from colostrum of Korean women by repeated gel filtration on Sephadex G-200 and Sepharose 6B, but bovine SigA was not cleary purified from bovine colostrum of Holstein cows by anion exchange chromatography using DEAE-Sephadex A-50 and gel filtration on Sephadex G-200 and Sepharose 6B. 2. The immunochemical properties of fractions from gel filtration on the Sephadex G-200 and Sepharose 6B column as assessed by Immunoelectrophoresis and double Immunodiffusion to identify the presence of IgM in first peak fraction, and the presence of pure SIgA in second peak fraction. However, Bovine SigA rich fraction from bovine colostrum of Holstein cows contained a large amount of $IgG_1$-dimer in addition to SIgA. 3. The fragments of reduced bovine colostrum SIgA rich fraction were estimated to have molecular weights of secretory component, heavy chain and light chain (75,000-80,000, 50,000-60,000, 25,000-27,000 daltons) by SDS-PAGE, respectively. Those were similar to the molecular weight of reduced SIgA from human milk.

• Journal of Life Science
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• v.30 no.2
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• pp.137-146
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• 2020

Calcium is one of the important secondary signaling molecules in plant cells. Calcium-dependent protein kinases (CDPK)-the sensor proteins of Ca²⁺ and phosphorylating enzymes-are the most abundant serine/threonine kinases in plant cells. They convert and transmit signals in response to various stimuli, resulting in specific responses in plants. In rice, 31 CDPK gene families have been identified, which are mainly involved in plant growth and development and are known to play roles in response to various stress conditions. However, little is known about the biochemical characteristics of CDPK proteins. In this study, OsCPK11-a CDPK in rice-was partially purified, and its biochemical characteristics were found. Partially purified OsCPK11 from rice seedlings was obtained by three-step column chromatography that involved anion exchange chromatography consisting of DEAE, hydrophobic interaction chromatography consisting of phenyl-Sepharose, and gel filtration chromatography consisting of Sephacryl-200HR. An in vitro kinase assay using partially purified OsCPK11 was also performed. This partially purified OsCPK11 had a molecular weight of 54 kDa and showed a strong hydrophobic interaction with the hydrophobic resin. In vitro kinase assay showed that the OsCPK11 also had Ca²⁺-dependent autophosphorylation activity. The OsCPK11 phosphorylated histone III-S, and the optimum pH for its kinase activity was found to be 7.5~8.0. The native OsCPK11 shared several biochemical characteristics with recombinant OsCPK11 studied previously, and both had Ca²⁺-dependent autophosphorylation activity and favored histone III-S as a substrate for kinase activity, which also had a Ca²⁺-dependence.

• Applied Biological Chemistry
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• v.13 no.2
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• pp.111-129
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• 1970

As a series of studies on the nucleic acids and their related substances 210 samples were collected from 76 places such as farm soil, compost of heap, nuruk and meju to obtain microbial strains which produce 5'-phosphodiesterase. From these samples total of 758 strains were isolated by the use of dilution pour plate method. For all isolated strains primary screening of the productivity of RNA depolymerase was performed and useful strains with regard to 5'-phosphodiesterase productivities were identified. For these useful strains optimum condition, the effect of various compounds on the activity of 5'-phosphodiesterase, and the optimum condition for enzyme reaction were discussed. The quantitative of 5'-mononucleotides produced by the action of 5'-phosphodiesterase was performed using anion-exchange column chromatography and their identified was done by paper chromatography, thinlayer chromatography, ultra violet spectrophotometry, and characteristic color reaction using carbazole and schiff's reagent. (1) Penicillium citreo-viride PO 2-11 and Streptomyces aureus SOA 4-21 from soil were identified as a potent 5'-phosphodiesterase producing strains. (2) Optimum culture conditions for Penicillium citreo-viride PO 2-11 strain isolated were found to be pH 5.0 and $30^{\circ}C$, and the optimum conditions for enzyme action of 5'-phosphodiesterase were pH 4.2 and $60^{\circ}C$. Best carbon source for the production of 5'-phosphodiesterase was found to be sucrose and ammonium nitrate for nitrogen source. Addition of 0.01% corn steep liquor or yeast extract exhibited 20% increase in the amount of 5'-phosphodiesterase production compared to the control. 5'-phosphodiesterase produced by this strain was activated by $Mg^{++},\;Ca^{++},\;Zn^{++},\;Mn^{++}$ and was inhibited by EDTA, citrate, $Cu^{++},\;CO^{++}$. 5'-phosphodiesterase produced 5'-mononucleotide from RNA at a rate of 65.81%, and among the 5'-mononucleotides accumulated 5'-GMP only was found to have flavorous and the strain was also found lack of 5'-AMP deaminase. Productivity of flavorous 5'-GMP was found to be 186.7mg per gram of RNA. (3) Optimum culture canditions for the isolated Streptomyces aureus SOA 4-21 strain were pH 7.0 and $28^{\circ}C$, and the optimum conditions for the action of 5'-phosphodiesterase were pH 7.3 and $50^{\circ}C$. The best carbon source for 5'-phosphodiesterase production was found to be glucose and that of nitrogen was asparagine. Addition of 0.01% yeast extract exhibited increased productivity of 5'-phosphodiesterase by 40% compared to the non-added control. 5'-phosphodiesterase produced by this strain was activated by $Ca^{++},\;Zn^{++},\;Mn^{++}$ and was inhibited by citrate, EDTA, $Cu^{++}$. It was also found that the strain produce 5'-AMP deaminase in addition to 5'-phosphodiesterase. For this reason although decomposition rate was 63.58% the accumulation of 5'-AMP, 5'-CMP, 5'-GMP and 5'-UMP occurred by the breakdown of RNA. In the course of these reaction 5'-AMP deaminase converted 60% of 5'-AMP thus produced into 5'-IMP and flavorous 5'-mono nucleotide production was significantly increased by this strain over the above mentioned one. Production rates were found to be 171.8mg per grain of RNA for 5'-IMP and 148.2mg per gram of RNA for 5'-GMP, respectively.

• Korean Journal of Food Science and Technology
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• v.6 no.3
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• pp.177-184
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• 1974

File fish Navodon modestus was dehydrated in cabinet type hot-sir drier at $48-50^{\circ}C$ for 11 hours and also yellowfin puffer Fugu xanthopterum was dried in open air at $26-28^{\circ}C$ for 30 hours. Nucleotides and their related compounds were collected by extraction with cold perchloric acid and their amounts were determined by anion exchange column chromatography. The contents of ADP, IMP, ATP and hypoxanthine in fresh file fish muscle were 22.9, 12.1, 4.9, and 3.2 ${\mu}mole/g,$ dry wt. respectively. AMP and inosine were 0.9 ${\mu}mole/g,$ dry wt. equally. In fresh yellowfin puffer muscle, the contents of ADP, ATP, AMP, inosine and hypoxanthine were 25.6, 2.4, 1.6, 0.3, 0.6, and 0.4 ${\mu}mole/g,$ dry wt. respectively. In the case of file fish, ADP and ATP tended to degrade rapidly during hot-air dehydration. The contents of IMP were decreased slightly while AMP and inosine were increased. And another case of yellowfin puffer, ADP also tended to degrade rapidly during sun drying while AMP, IMP, inosine and hypoxanthine were increased. Especially, in both case of file fish and yellowfin puffer, inosine was increased twenty five and thirty five times during drying respectively.