• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1636-1643
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• 2012

Enzymatic pre-bleaching by modification of pulp fibers with xylanases is an attractive approach to reduce the consumption of toxic bleaching chemicals in the paper industry. In this study, an alkaliphilic endoxylanase gene was isolated from metagenomic DNA of a structurally stable thermophilic lignocellulose-degrading microbial consortium using amplification with conserved glycosyl hydrolase family 10 primers and subsequent genome walking. The full-length xylanase showed 78% sequence identity to an endo-${\beta}$-1,4-xylanase of Clostridium phytofermentans and was expressed in a mature form with an N-terminal His6 tag fusion in Escherichia coli. The recombinant xylanase Xyn3F was thermotolerant and alkaliphilic, working optimally at $65-70^{\circ}C$ with an optimal pH at 9-10 and retaining >80% activity at pH 9, $60^{\circ}C$ for 1 h. Xyn3F showed a $V_{max}$ of 2,327 IU/mg and $K_m$ of 3.5 mg/ml on birchwood xylan. Pre-bleaching of industrial eucalyptus pulp with no prior pH adjustment (pH 9) using Xyn3F at 50 IU/g dried pulp led to 4.5-5.1% increase in final pulp brightness and 90.4-102.4% increase in whiteness after a single-step hypochlorite bleaching over the untreated pulp, which allowed at least 20% decrease in hypochlorite consumption to achieve the same final bleaching indices. The alkaliphilic xylanase is promising for application in an environmentally friendly bleaching step of kraft and soda pulps with no requirement for pH adjustment, leading to improved economic feasibility of the process.

• Journal of Animal Science and Technology
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• v.47 no.1
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• pp.39-48
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• 2005

Outside muscle of pork ham were cut to cube(7 $\times$ 10 $\times$2 ern) and three Korea traditional seasonings such as soybean paste(Tl), garlic paste(T2), red pepper paste(T3) were seasoned by the proportions of meat to seasonings(1 : 1), respectively. The seasoned samples were fermented by fill into plastic box at 0 $\pm$ 1 $^{\circ}C$ for 10 days. And then, the fermented meat from each pack was vacuum-packaged and stored at 0 $\pm$ 1 $^{\circ}C$ for up to 9 weeks. pH and shear force were decreased during storage periods in all treatment groups and WHC was decreased with storage in T2. The saccarinity of T1 was increased and salinity increased during storage in all treatment groups. pH of T2 was increased than that of other treatments, while decreased saccarinity and shear force of in T2. The salinity were higher in the order of T1 > T2 > T3. Volatile basic nitrogen (VBN) value were increased with storage in all treatment groups. Thiobarbituric acid reactive substances (TSARS) value of Tl was increased with storage while it was decreased T2. Thiobarbituric acid reactive substances(TSARS) value was higher in the order of T1 > T3 > T2 at 9weeks of storage. Surface meat L' values of T1 was increased with storage and T3 decreased with storage whereas, surface meat a' values of T1 was decreased with storage, and T2 was increased with storage. Surface meat b' values of T3 was decreased with storage. Escherichia coli were decreased during storage periods in all treatment groups.

• Korean Journal of Veterinary Research
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• v.42 no.1
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• pp.45-54
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• 2002

The study was carried out to characterize the pharmacokinetics after intravenous (iv, 20 mg/kg) and oral (p.o. 100 mg/kg) administration as oxytetracycline (OTC) and tiamulin (TIA) mixture in swine and to determine interaction between OTC and TIA against various pig pathogenic bacteria. The antibacterial effects of OTC in combination with TIA in vitro showed synergistic effect against Salmonella typhimurium 1925, Pasteurella multocida Type A, P. multocida Type D, Krebsiella Pneumoniae 2001, K. Pneumoniae 1560, K. Pneumoniae 2208, Haemophillus pleuropneumonia S 2, and H. pleuropneumonia S 5, but against additive effect E. coli K88ab and S. choleraesuis on the basis of fractional inhibitory concentration (FIC) index. On the while, after i.v. and p.o. administration of OTC and TIA mixture, each OTC and TIA concentrations in plasma were fitted to an open two-compartment model. After i.v. administration of OTC-TIA mixture, the mean distribution half-life ($T_{1/2{\alpha}}$) of OTC and TIA in plasma showed 0.29 h and 0.17 h, and the mean elimination half-life ($T_{1/2{\beta}}$) of those was 4.36 h and 6.64 h, respectively. The mean volume of distribution at steady state ($Vd_{ss}$) of OTC and TIA was $0.85{\ell}/kg$ and $2.44{\ell}/kg$, respectively. After oral administration of OTC and TIA mixture, the mean maximal absorption concentrations ($C_{max}$) of OTC and TIA were $0.60{\mu}g/m{\ell}$ at 1.07 h ($T_{max}$) and $1.68{\mu}g/m{\ell}$ at 1.85 h ($T_{max}$), respectively. The mean elimination half-life ($T_{1/2{\beta}}$) of those showed 6.84 h and 6.36 h. In conclusion, we could suggest in this study that the combination of OTC and TIA may be recommended for the antibacterial therapy against polymicrobial infections, and both OTC and TIA showed large distribution to tissues and high $C_{max}$ after p.o. administration.

• Proceedings of the Korean Society of Life Science Conference
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• 2001.06a
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• pp.67-86
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• 2001

A strain producing strongly fibrinolytic enzyme was isolated from soil and was identified to be Bacillus subtilis by biochemical and physiological characterization. The optimal culture conditions for the production of fibrinolytic enzyme was determined to be 1.0% tryptone, 1.5% soluble starch, 0.5% Peptone, 0.5% NaCl, $(NH_{4})_{3}PO_4.3H_{2}O, and MgSO_{4}.7H_{2}O.$ Initial pH and temperature were pH 8.0 and $30^{\circ}C$ , respectively, The highest enzyme production was observed at 30 hours of cultivation at $30^{\circ}C$ The fibrinolytic enzyme was purified to homogeneity by DEAE Sephadex A-50 ion exchange column chromatography, 70% ammonium sulfate precipitation, Sephadex G-200 and G-75 gel filtration column chromatography. The molecular weight of the purified enzyme was 28,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A gene encoding the fibrinolytic enzyme was cloned into a plasmid vector pBluescript, transforming E.coli XL-1 Blue. The clone was able to degrade fibrin, This indicated that the gene could encode a fibrinolytic enzyme. The nucleotide sequence of the 2.7 kb insert was determined in both direction. One open reading frame composed of 1023 nucleotides was found to be a potential protein coding region. There was the putative Shine-Dalgano sequence and TATA box upstream of the open reading frame. The homology search data in the genome database showed that both the 2.7 kb insert and 1 kb open reading frame carried no significance in the nucleotide sequence of known fibrinolytic enzyme from Bacillus serovars. The recombinant cell harboring the novel gene involved in fibrinolysis was subjected to protein purification. The molecular mass of the purified fibrinolytic enzyme was determined to be 31864 Dalton, which was highly in accordance with the molecular mass(33 kDa) of the fibrinolytic gene deduced from the insert. The fibrinolytic enzyme was Purified 50.5 folds to homogeneity in overall yield of 10.7% by DEAE Sephadex A-50 ion exchange, 85% ammonium sulfate precipitation, Sephadex G-50, Superdex 75 HR FPLC gel filtration. In conclusion, a novel fibrinolytic gene from Bacillus subtilis was identified and characterized by cloning a genomic library of Bacillus subtilis into pBleuscript. For the soybean fermented by this strain, it is found that there increased assistant protein about 20% compared to the soybean not fermented and increased about 30% according to amino acid analysis and, in particular, essential amino acid increased about 40%. When keeping this fermented soybean powder at room temperature for about 70days, it showed very high stability maintaining almost perfect activity and, therefore, it gave us great suggestion its possibility of development as a new functional food.

• Journal of Life Science
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• v.21 no.2
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• pp.221-226
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• 2011

The gene encoding 4-$\alpha$-glucanotransferase (mgtA) from Thermotoga neapolitana was cloned and expressed in Escherichia coli in order to investigate whether this enzyme was capable of producing cycloamylose for industrial applications. MgtA was purified to homogeneity by HiTrap Q HP and Sephacryl S-200 HR column chromatographies. The size of the enzyme as determined by SDS-PAGE was about 52 kDa, which was in good agreement with its deduced molecular mass of 51.9 kDa. The optimal temperature and pH for the activity of the 4-$\alpha$-glucanotransferase was found to be $85^{\circ}C$ and 6.5, respectively. The enzyme hydrolyzed the 1,4-$\alpha$-glucosidic bonds in oligomeric 1,4-$\alpha$-glucans and transferred oligosaccharides (maltotriose being the shortest one) to acceptor maltodextrins. However, the enzymes had no activity against pullulan, glycogen, and other di- or trioligosaccharides with rare types of $\alpha$-bond. MgtA is distinguished from 4-$\alpha$-glucanotransferase from Thermotoga maritima in that it can convert maltotriose into maltooligosaccharides. The treatment of glucoamylase after the reaction of MgtA with maltotriose, maltotetraose, maltopentaose, or maltohexaose as sole substrate revealed that MgtA yielded linear maltooligosaccharides instead of cycloamylose.

• Molecules and Cells
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• v.27 no.4
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• pp.423-428
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• 2009

Superoxide dismutases (SODs) constitute the first line of cellular defense against oxidative stress in plants. SODs generally occur in three different forms with Cu/Zn, Fe, or Mn as prosthetic metals. We cloned the full-length cDNA of the Thellungiella halophila Cu/Zn-SOD gene ThCSD using degenerate RT-PCR and rapid amplification of cDNA ends (RACE). Sequence analysis indicated that the ThCSD gene (GenBank accession number EF405867) had an open reading frame of 456 bp. The deduced 152-amino acid polypeptide had a predicted molecular weight of 15.1 kDa, an estimated pI of 5.4, and a putative Cu/Zn-binding site. Recombinant ThCSD protein was expressed in Escherichia coli and assayed for SOD enzymatic activity in a native polyacrylamide gel. The SOD activity of ThCSD was inactivated by potassium cyanide and hydrogen peroxide but not by sodium azide, confirming that ThCSD is a Cu/Zn-SOD. Northern blotting demonstrated that ThCSD is expressed in roots, stems, and leaves. ThCSD mRNA levels increased by about 30-fold when plants were treated with sodium chloride (NaCl), abscisic acid (ABA), and indole-acetic acid (IAA) and by about 50-fold when treated with UVB light. These results indicate that ThCSD is involved in physiological pathways activated by a variety of environmental conditions.

• Journal of Animal Environmental Science
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• v.2 no.1
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• pp.53-62
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• 1996

This experiment was conducted to investigate the effect of the reuse of sawdust fermented with swine excretion as bed material on the growth performance of pigs. The sawdust which was already fermented with swine excretion in the pig house for eight months was transported to a fermentation facility for secondary fermentation. A total of 96 pigs with average 30kg of initial body weight were randomly assigned in the $2{\times}2$ factorial design with two levels(0%, 1.5%) of probiotics added for secondary fermentation and two levels(0%, 1.5%) of probiotics in feed. The results obtained are as follows : 1. Total-nitrogen(T-N), $K_2O$, total-carbon(T-C), and carbon/nitrogen(C/N) in sawdust bed showed no significant difference within treatments, but phosphate increased by 57% in average compared to the initial. 2. There was no significant difference in temperature in the sawdust bed treatments. 3. The internal parasite eggs detected were Trichuris suis, Strong. ransomi, Ascaris suum, Coccidia and Balantidium coli. 4. The utilization period of sawdust fermented with swine excretion was 52, 26, 16, 4, 5, 3 days, respectively, with increase of body weight. 5. Average daily gain and feed conversion were significantly improved by adding probiotics in the feed(P<0.05), but there was no difference between fermented sawdust with or without probiotics. 6. There was no significant difference in carcass weight and backfat thickness of pig among treatments(P>0.05).

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.916-922
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• 2005

Parkin, known as an E3 ubiquitin ligase, has essential role in protein quality control, and its severe dysfunction leads to neurodegenerative disorders. Human Parkin was excessively degraded when expressed in Escherichia coli under the conventional induction condition ($37^{\circ}C$ culture condition with 0.5 mM IPTG). To optimize the induction and culture conditions for recombinant human Parkin and develop a rapid method for the Parkin purification, we expressed Parkin by using PCEX system at the different culture temperatures and IPTC concentrations. The intact Parkin protein was purified to approximately $90\%$ purity with suitable amounts of protein under the optimal culture condition ($25^{\circ}C$E with 0.01 mM IPTG). Additionally, we constructed various parkin plasmids with different tagging systems and investigated their expression patterns in HEK293 cells. We found that the proteolytically sensitive site is localized within a ubiquitin-like domain of Parkin. This study developes a method for generating useful reagents to investigate biochemical properties of Parkin.

• Journal of Life Science
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• v.12 no.3
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• pp.264-273
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• 2002

We have isolated and artificially expressed three cDNA clones of Capsicum annuum PR5 genes for elucidating the antifungal activity against Phytophthora capsici which contracted a hot pepper root rot in field condition. Three divergent PR5 proteins from hot pepper were designated as CAPR5-1 and CAPR5-2 from susceptible cultivar (Subicho) as well as CAPR5-3 from resistant cultivar (CM331) in response to P. capsici. The cDNA similarity was found over 80% of identity among the three CAPR5s, and deduced amino acid sequence was characterized that all of CAPR5s contained 16 cysteine residues which possibly had a significant role in the structural formation. The result of genomic DNA blot showed that CAPR5-1 and CAPR5-2 existed as single copy in the Subicho genome. Three recombinant CPARs in E. coli were identified by SDS-PACE, and each expressed protein was treated on the PDA medium which contained cultured pathogens. Although three CAPR5 proteins did not affected the hyphal growth of Glomerella glycines and Colletotrichum fagenarium, CAPR5-1, CAPR5-2, and CAPR5-3 showed a specific antifungal activities against P. capsici.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.964-969
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• 1998

To investigated the anticarcinogenic activity of 70% ethanol extracts from various cereal in vitro, antimutagenic activity, inhibitory effect of DNA strand scission and tumor promotion were examined. The antimutagenic activity of the beans such as black bean and small red bean was generally higher than that of cereals examined. However inhibitory activity of 70% ethanolic extracts against DNA strand scission induced mitomycin C showed that millet, job's tear, black bean and soy bean among cereals and beans tested in this study inhibited effectively the DNA strand scission. Antioxidative activity of some cereal extracts determined by using linoleic acid model system showed that Job's tear, millet and black bean were higher antioxidative activity than other cereals and beans. Conventional short-term antipromoter assay system using activation of Epstein Barr virus (EBV) clearly demonstrated that sorghum, buckwheat, black bean and small red bean have inhibitory effects on promotion in cellular carcinogenesis.