• Parasites, Hosts and Diseases
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• v.31 no.3
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• pp.259-268
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• 1993

When activity of peroxidase in auld Pnrqfonimn westermqni was monitored using o-dianisidine and $H_2O_2$ as substrates, its specific activity was 1.5 times higher In excretory-secretory product (ESP) than in crude extract. The one was purified by two purification steps of Sephacryl S-300 Superfine gel permeation and DEAE-Trisacryl M anion exchange chromatographies. Its activity increased 16.9 fold with 32.3% recovery. The enzyme was inhibited totally by 1 millimoles of dithiothreitol (DTT), 2-mercaptoethanol and azide. Molecular mass was 16 kDa in reducing SDS-polyacrylamide gel electrophoresis (PAGE) or 19 kDa in TSK-Blue gel filtration high performance liquid chromatography (HPLC). respectively. Special staining for peroxidase by diaminobenzidine on SDS-PAGE confirmed the activity. The peroxidase was less reactive to a paragonimiasis serum when observed by SDS-PAGE/immunoblot. In addition, specific activities of superoxide dismutase (SOD) and catalase were also identified in the ESP. High activities of these antioxidant enzymes in ESP indicate that they are parts of defense mechanisms against reactive oxygen intermediates from host.

• Journal of Life Science
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• v.21 no.11
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• pp.1565-1572
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• 2011

Eye-specific lactate dehydrogenase (EC 1.1.1.27, LDH) $C_4$ isozyme in the eyes of greenlings (Hexagrammos otakii) was successfully purified by affinity chromatography and continuous-elution electrophoresis. The molecular weight of the purified eye-specific LDH $C_4$ isozyme was 154.8 kDa, as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Optimal pH for enzymatic reaction of the eye-specific LDH $C_4$ isozyme was pH 8.5. $K^{PYR}_m$ value of the purified eye-specific LDH $C_4$ isozyme was $1.88{\times}10^{-5}$ M using pyruvate as a substrate. These results indicate that we must consider pH when measuring eye-specific LDH $C_4$ isozyme activity. The eye-specific LDH $C_4$ isozyme had a higher binding affinity for the substrate as a pyruvate than LDH A4 isozyme. Antibodies produced against the purified eye-specific LDH $C_4$ isozyme may be used in the diagnosis of several human diseases and in comparative physiological studies of fishes.

• Resources Recycling
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• v.18 no.5
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• pp.19-25
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• 2009

Molybdenite concentrate ($MoS_2$) is the major mineral for the molybdenum industry, of which the industrial processing is first converted to technical grade molybdenum trioxide ($MoO_3$) by its oxidative roasting and purification, used as a raw material for manufacturing several molybdenum compounds. In the present work, detailed experimental results for the oxidative roasting of low grade Mongolian molybdenite concentrate are presented. The experiments were carried out in the temperature range of 793 to 823 K under an oxygen partial pressure range of 0.08 atm to 0.21 atm by using a thermogravimetric analysis technique. The molybdenite concentrate was an average particle size of $67\;{\mu}m$. In the oxidative roasting of low grade Mongolian molybdenite concentrate, more than 95% of molybdenite was converted to molybdenum trioxide in 60 min. at 828 K. The lander equation was found to be useful in describing the rates of the oxidative roasting and the reaction order with respect to oxygen concentration in a gaseous mixture with nitrogen was 0.11 order.

• KSBB Journal
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• v.19 no.1
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• pp.50-56
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• 2004

The aim of this work was to investigate the purification and characterization dixoygenases isolated from Delftia sp. JK-2, which could utilize aniline, benzoate, and p-hydroxybenoate as sole carbon and energy source. Catechol 1,2-dioxygenase (C1, 2O), catechol 2,3-dioxygenase(C2, 3O), and protocatechuate 4,5-dioxygenase(4,5-PCD) were isolated by benzoate, aniline, and p-hydroxybenzoate. In initial experiments, several characteristics of C1 ,2O, C2, 3O, and 4,5-PCD separated with ammonium sulfate precipitation, DEAE-sepharose, and Q-sepharose were investigated. Specific activity of C1 ,2O, C2, 3O, and 4,5-PCD were approximately 3.3 unit/mg, 4.7 unit/mg, and 2.0 unit/mg. C1 ,2O and C2, 3O demonstrated their enzyme activities to other substrates, catechol and 4-methylcatechol. 4,5-PCD showed the specific activity to the only substrate, protocatechuate, but the substrates(e.g., catechol, 3-methylcatechol, 4-methylcatechol, 4-chlorocatechol, 4-nitrocatechol) did not show any specific activities in this work. The optimum temperature of C1, 2O, C2, 3O, and 4,5-PCD were 30$^{\circ}C$, and the optimal pHs were approximately 8, 8, and 7, respectively. Ag$\^$+/, Hg$\^$+/, Cu$\^$2+/ showed inhibitory effect on the activity of C1, 2O and C2, 3O, but Ag$\^$+/, Hg$\^$+/, Cu$\^$2+/, Fe$\^$3+/ showed inhibitory effect on the activity of 4,5-PCD. Molecular weight of the C1, 2O, C2, 3O, and 4,5-PCD were determined to approximately 60 kDa,35 kDa, and 62 kDa by SDS-PAGE.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.05a
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• pp.89-119
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• 2004

This study was conducted to isolate lactobacilli having probiotic characteristics to be used as health adjuncts with fermented milk products. Acid tolerant strains were selected in Lactobacilli MRS broth adjusted to pH 4.0 from 80 healthy persons (infants, children and adults). And bile tolerant strains were examined in Lactobacilli MRS broth in which 1.0% bile salt was added. By estimation above characteristics, the strains No. 27, which was isolated from adult feces, was selected and identified as Lactobacillus salivarius subsp. salivarius based on carbohydrate fermentation and 16S rDNA sequencing. It was used as a probiotic strain in fermented milk products. The pH of fermented milk decreased from pH 6.7 to 5.0 and titratable acidity increased from 0.3% to 1.0% by L. salivarius subsp. salivarius (isolation strain 20, 35, and 37), when incubated for 36 h at $37^{\circ}C$. The number of viable cell counts of fermented milk was maximized at this incubation condition. The SDS-PAGE evidenced no significant change of casein but distinct changes of whey protein were observed by isolated L. salivarius subsp. salivarius for titratable acidity being incubated by $0.9{\sim}1.0%$ at $37^{\circ}C$. All of the strains produced 83.43 to 131.96 mM of lactic acid and 5.39 to 26.85 mM of isobutyric acid in fermented products. The in vitro culture experiment was performed to evaluate ability to reduce cholesterol levels and antimicrobial activity in the growth medium. The selected L. salivarius subsp. salivarius reduced $23{\sim}38%$ of cholesterol content in lactobacilli MRS broth during bacterial growth for 24 hours at $37^{\circ}C$. All of the isolated L. salivarius subsp. salivarius had an excellent antibacterial activity with $15{\sim}25$ mm of inhibition zone to E. coli KCTC1039, S. enteritidis KCCM3313, S. typhimurium M-15, and S. typhimurium KCCM40253 when its pH had not been adjusted. Also, all of the isolated L. salivarius subsp. salivarius had partial inhibition zone to E. coli KCTC1039, E. coli KCTC0115 and S. enteritidis KCCM3313 when it had been adjusted to pH 5.7. The selected strains were determined to have resistances of twelve antibiotic. Strains 27 and 35 among the L. salivarius subsp. salivarius showed the highest resistance to the antibiotics. Purified ${\alpha}$-galactosidase was obtained by DEAE-Sephadex A-50 ion exchange chromatography, Mono-Q ion exchange chromatography and HPLC column chromatography from L. salivarius subsp. salivarius 27. The specific activity of the purified enzyme was 8,994 units/mg protein, representing an 17.09 folds purification of the original cell crude extract. The molecular weight of enzyme was identified about 53,000 dalton by 12% SDS-PAGE. Optimal temperature and pH for activity of this enzyme were $40^{\circ}C$ and 7.0 respectively. The enzyme was found to be stable between 25 and $50^{\circ}C$. ${\alpha}$-galactosidase activity was lost rapidly below pH 5.0 and above pH 9.0. This enzyme was liberated galactose from melibiose, raffinose, and stachyose, and also the hydrolysis rate of substrate was compound by HPLC. These results indicated that some of the L. salivarius subsp. salivarius (strain 27 and 35) are considered as effective probiotic strains with a potential for industrial applications, but the further study is needed to establish their use as probiotics in vivo.

• Parasites, Hosts and Diseases
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• v.24 no.2
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• pp.145-158
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• 1986

This study was undertaken to purify cystic fluid (CF) antigen of Taenia solium metacestodes by affinity chromatogaphy using specific monoclonal antibody(McAb) and to characterize the antigenicity of the purified antigen. The hybridoma cell lines, prepared by fusion between mouse plasmacytoma and spleen cells from BALB/c mice immunized with CF, secreted antibodies reacting to various helminthic antigens. Majority of cell lines reacted to CF only but some also reacted to parenchymal antigen of T. solium metacestodes, adult T. saginata, sparganum, hydatid cystic fluid, Paragonimus westermani and Clonorchis sinensis, either in combination with CF, other antigens or independently. Cloned cells derived from monoclonal lines also produced antibodies reacting either to CF only or to other helminthes in combination or independently. These results indicated that CF of T. solium metacestodes contained proteins which possessed antigenic determinants not only specific to CF but also cross reactive with the afore-mentioned helminthes. CF of T. solium metacestodes was purified by affinity chromatography using the McAb which reacted to CF and parenchymal antigens. The affinity-purified antigen (A-Ag) and unbound pool CF (U-Ag) were separated. A-Ag showed 2 protein bands by disc-PAGE whereas CF exhibited 6 bands and U-Ag consisted of all bands CF had. The diagnostic significance of A-Ag was evaluated by ELISA in human neurocysticercosis and other helminthic and neurologic diseases. By A-Ag, the levels of the specific IgG antibody, as shown by absorbance in sera and CSF, were lower than those of CF and U-Ag. Accordingly, the sensitivity was about 70% of CF and U-Ag. However, the nonspecific positive reactions to CF and U-Ag, observed in sparganosis, T. saginata infection and paragonimiasis did not occur when A-Ag was used. These results indicated that the affinity-purified A-Ag had the higher specificity but the lower sensitivity as a diagnostic antigen in cysticercosis, probably because it only detected a single or limited numbers of monospecific antibodies among the diverse polyclonal antibodies produced in the patients with neurocysticercosis.

• Microbiology and Biotechnology Letters
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• v.40 no.1
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• pp.57-65
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• 2012

Antifungal compounds from Bacillus polyfermenticus CJ6 were purified using SPE, preparative HPLC, and reverse phase-HPLC. Antifungal compounds from B. polyfermenticus CJ6 were separated into three fractions (8, B, C) using preparative HPLC. LC/MS analysis of antifungal peaks suggested that B. polyfermenticus CJ6 produces lipopeptides; two kinds of iturin A ($C_{14}$, $C_{15}$), three kinds of surfactins ($C_{13}$, $C_{14}$, $C_{15}$), four kinds of fengycin A ($C_{14}$, $C_{15}$, $C_{16}$, $C_{17}$) and two kinds fengycin B ($C_{16}$, $C_{17}$). The antifungal activity of fraction 8, which was presumed as inturin A, was found to be stable after the pH, heat or proteolytic enzyme treatment, but it was unstable at 50-$70^{\circ}C$ for 24 hr. The antifungal activity of fraction B, which presumed as surfactins and fengycin A, was found to be stable after the heat treatment, but it was unstable in the pH 3.0 and after the protease (type I) or ${\alpha}$-chymotrypsin treatment. The antifungal activity of fraction C, which was presumed as fengycin A and B, was found to be stable in the pH 3.0-9.0 range and the heat treatment, but it was unstable with the treatment of protease (type I). The amino acid composition of the purified peaks 8-1 and 8-2 were Asx, Tyr, Gln, Pro, and Ser in a molar ratio of 3:1:1:1:1, which showed the same amino acid composition as iturin. From these results, we confirmed that antifungal compounds from B. polyfermenticus CJ6 most likely belonged to iturin A as well as surfactins and fengycins. As lipopeptides are known to act in a synergistic manner, the antifungal compounds from B. polyfermenticus CJ6 might have potential uses in biotechnology and biopharmaceutical applications.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.5
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• pp.482-494
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• 1994

Most of carotenoprotein complexes have been extracted by using buffered solutions. However, in this study carotenoprotein from the muscle of Blue mussel(Mytilus edulis) was extracted by a detergent such as Triton X-100. It was purified and characterized by $20\%$ (w/v) $(NH_4)_2SO_4$, DEAE-cellulose ion exchange and Sephacryl S-300 gel filtration. The carotenoprotein(${\lambda}_{max}=462nm$) had an approximate M. W. of 372KDa(gel filtration). SDS-PAGE analysis of the carotenoprotein indicated the presence of four polypeptides of 60KDa($23.70\%$), 46.9KDa($9.14\%$), 26KDa($49.14\%$) and 13KDa($18.02\%$). Carotenoprotein denaturated by treatment with SDS to a final concentration of $0.2\%$ (w/v) caused a hypsochromic shift of ${\lambda}_{max}$ from 462nm to 456nm. The carotenoprotein contained lipids as structure units. The amino acid composition of the carotenoprotein contained large essential amino acid amounts of $62.8\%$, and the content of threonine($35.9\%$) was higher than other amino acids, but histidine, methionine and proline were not present. In the carotenoprotein, the major fatty acids were $C_{16:4},\;C_{16:0},\;C_{20:5}\;and\;C_{22:6}$. The percentages of polyunsaturated fatty acids($62.4\%$) were higher compared to other fatty acids(saturated fatty acids $19.6\%$, monounsaturated fatty acids $18.0\%$). Carotenoid was extracted from the carotenoprotein by acetone and it was separated into five different components by preparative TLC(benzene:petroleum ether:acetone=69:17:14). The major components of carotenoid were mytiloxanthin($74.79\%$) and 3,4,3'- trihydroxy-7',8'-didehydro-${\beta}$-carotene($18.26\%$), and they were at least presented as prosthetic groups of carotenoprotein.

• 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.

• Clean Technology
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• v.13 no.1 s.36
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• pp.54-63
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• 2007

Even traces of CO in the hydrogen-rich feed gas to proton exchange membrane fuel cells (PEMFC) poison the platinum anode electrode and dramatically decrease the power output. In this work, a variety of catalytic materials consisting of $Cu/Ce_xZr_{1-x}O_2$, (x = 0.0-1.0) were synthesised, characterized and tested for CO oxidation and preferential oxidation of CO (PROX). These catalysts prepared by hydrothermal and deposition-precipitation methods. The catalysts were characterized by XRD, XRF, SEM, BET, $N_2O$ titration and oxygen storage capacity (OSC) measurement. The effects of composition of the support and degree of excess oxygen were investigated fur activity and $CO_2$ selectivity with different temperatures. The composition of the support markedly influenced the PROX activity. Among the various $Cu/Ce_xZr_{1-x}O_2$ catalysts having different composition, $Cu/Ce_{0.9}Zr_{0.1}O_2$ and $Cu/Ce_{0.7}Zr_{0.3}O_2$ showed the highest activities (>99%) and selectivities (ca.50%) in the temperature range of $150{\sim}160^{\circ}C$. It was found that by using of $Ce_xZr_{1-x}O_2$ mixed oxide support which possesses a high oxygen storage capacity, oxidation-reduction activity of Cu-based catalyst was improved, which resulted in the increase of catalytic activity and selectivity of CO oxidation in excess $H_2$ environments.