• Korean Journal of Food Science and Technology
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• v.18 no.4
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• pp.288-293
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• 1986

A raw starch-digesting enzyme from Rhizopus oryzae was purified by ammonium sulfate fractionation, DEAE-sephacel column chromatography and Sephadex G-150 gel filtration. The specific activity of purified enzyme was 45.2 Ulmg protein and the yield was 16.2%. The purified enzyme was found to be homogeneous bypolyacrylamide gel electrophoresis and its molecular weight was estimated to be 67,000 by SDS-polyacrylamide gel electrophoresis, and also the enzyme had Km value of 4.082 mg/ml for raw corn starch. The optimal temperature and pH for the enzyme activity were $50^{\circ}C$ and 4.0-5.0, respectively. Reaction product of raw corn starch by purified enzyme was glucose mainly.

• Applied Biological Chemistry
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• v.46 no.3
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• pp.171-175
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• 2003

The putative endochitinase gene, yheB of Escherichia coli K-12 is not expressed under lab culture conditions. The endochitinase gene was amplified by PCR and subcloned into pET28c vector and pQE9 vector, respectively. The endochitinase produced in E. coli harboring pET28c containing yheB or pQE9 vector containing yheE was partly released into the growth medium. The overproduced endochitinase was partially purified by His affinity column chromatography and DE-52 column chromatography. The apparent molecular weight of the endochitinase determined by SDS-polyacrylamide gel electrophoresis was about 97,000. The purified E. coli endochitinase showed maximal chitinolytic activity at pH 6 and $40^{\circ}C$.

• The Plant Pathology Journal
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• v.29 no.2
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• pp.201-208
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• 2013

Drought stress is one of the major yield affecting factor for pepper plant. The effects of PGPRs were analyzed in relation with drought resistance. The PGPRs inoculated pepper plants tolerate the drought stress and survived as compared to non-inoculated pepper plants that died after 15 days of drought stress. Variations in protein and RNA accumulation patterns of inoculated and non-inoculated pepper plants subjected to drought conditions for 10 days were confirmed by two dimensional polyacrylamide gel electrophoresis (2D-PAGE) and differential display PCR (DD-PCR), respectively. A total of six differentially expressed stress proteins were identified in the treated pepper plants by 2D-PAGE. Among the stress proteins, specific genes of Cadhn, VA, sHSP and CaPR-10 showed more than a 1.5-fold expressed in amount in B. licheniformis K11-treated drought pepper compared to untreated drought pepper. The changes in proteins and gene expression patterns were attributed to the B. licheniformis K11. Accordingly, auxin and ACC deaminase producing PGPR B. licheniformis K11 could reduce drought stress in drought affected regions without the need for overusing agrochemicals and chemical fertilizer. These results will contribute to the development of a microbial agent for organic farming by PGPR.

• Korean Journal of Veterinary Research
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• v.39 no.1
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• pp.213-219
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• 1999

Microsatellite allele analysis has been used for individual identification and paternity test. In the present study, the biological father of three puppies was determined by using microsatellite allele amplification analysis. The mother bitch of the litter was a Poongsan dog. The three stud dogs that could have inseminated the bitch, by being in the same residence, were a white Poosan dog, a mixed breed, and a white Jindo dog. DNA was obtained from all the relevant dogs by buccal swabbing. Four loci of tetranucleotide repeat microsatellite were PCR-amplified, and analyzed by polyacrylamide gel electrophoresis and silver staining. The results of genotyping unambigously assigned the Poongsan dog as the biological father. There was no evidence of superfecundation. Therefore, the present study demonstrated the usefulness of microsatellite allele analysis as a simple, efficient method of paternity test in dogs.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.4
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• pp.27-33
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• 2000

A new technique for fractionating pulp stock into a long fiber portion and fines fraction was developed by KRICT in order to enhance the drainage and strength properties of recycled OCC pulp. In order to investigate the effect of fines contents in stock and stages of flotation on fractionation efficiency, flotations were performed at varied fines contents and flotation stages. Based on the result of multi-stage flotation fractionation it could be said that fines smaller than 15${\mu}{\textrm}{m}$ stabilize flotation froth of OCC. Although the amounts and the fines contents of flotation reject could be increased by multi-stage flotation fractionation of OCC, flotation stages more than 3 times were found to be inefficient in terms of fines concentrating degree. In order to satisfy the both conditions of reducing long fiber loss and of increasing flotation reject, several kinds of fractionating promoters were searched and investigated. And high molecular weight cationic polyacrylamide was chosen as a long fiber flocculating and flotation froth-stabilizing agent.

• Korean Journal of Microbiology
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• v.31 no.4
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• pp.306-311
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• 1993

The effects of methanol. used as a solvent for the hydrophobic substrate progesterone. on the morphology of Rhizopus nigricans and 11$\alpha$-hydroxylation of progesterone was investigated. The methanol tolerance of the 11$\alpha$-hydroxylase system in polyacrylamide immobilized R. nigricans mycelia as well as in free mycelia has been induced by adding various unsaturated fatty acids. biotin and ions into the cultivation medium. Immobilization of the cell seemed to protect the cells from denaturation by methanol. It gave higher reaction rate of progesterone than the free mycelia in the presence of methanol.500 $\mu$g/l of biotin was found to be the most effective induction agent for the methanol tolerance among tested chemicals. R. nixricans cells sustained its enzymatic activity at higher methanol concentrations as a result of accumulation of unsaturated fatty acids. especially oleic acid. in the membrane phospholipid.

• Journal of Microbiology
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• v.34 no.1
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• pp.90-94
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• 1996

The carboxymethyl cellulase (CMCase) was purified from the induced culture filtrate of hybrid TAPW15703 between Aspergillus niger and penicillium verruculosum made by nuclear transfer. The enzyme was purified 80 fold with an overall yield 17% from the culture medium by ammonium sulfate fractionation, Sephadex G-75 gel permeation chromatography, and DEAE-ion exchange column chromatography. The molecular weight of the CMCase has estimated to be 32,000 daltons on SDS-polyacrylamide gel electrophoresis and Sephadex G-150 gel permeation chromatography. The purified enzyme functions optimally at pH 4.0 and 4$0^{\circ}C$ The Km value for carbosymethyl cellulose was 68 mM. The enzyme activity was increased by the presence of $Mg^{2+}$and Mn$^{2+}$.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.145-146
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• 2000

The presence of cross-reacting muramidase in Lactobacillus delbrueckii ssp. bulgaricus ULl2 was shown by using monoclonal antibodies raised against an muramidase-2 of Enterococcus hirae ATCC 9790. The separation of protein by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by Western immunoblot confirmed the presence of one cross-reacting band in Enterococcus hirae with an estimated molecular mass of 80 kDa, L. bulgaricus cultured cells harvested after 4 and 12 h were submitted to different autolysin releasing procedures and the liberated products were allowed to cross-react with muramidase-2 antibodies in order to estimate the efficiency of each treatment. Although the cultured cells harvested after 4 h yielded only a slight immune-reaction in Western immunoblots against these enzyme monoclonal antibodies, a strong signal was observed for the cell walls obtained from the same experimental conditions and treated with Triton X-100 surfactant. The same phenomenon was also observed by light fluorescence microscopy. Immune-labelling followed by optical and electron microscopy have shown that the muramidase-2 of L. bulgaricus ULl2 was essentially localized in the innermost part of the cell wall.(omitted)

• Food Science and Biotechnology
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• v.18 no.1
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• pp.130-136
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• 2009

The present study was conducted to determine the protective ability of the ethanol extracts of Hypericum scabroides Robson & Poulter (HS) and Hypericum triquetrifolium Turra (HT) against the protein oxidation and DNA damage induced by Fenton system. The ability of HS and HT to prevent oxidative damage to bovine serum albumin (BSA) induced by $Fe^{3+}/H_2O_2$ and ascorbic acid was investigated. The ethanol extracts of HS and HT at different concentrations ($50-1,000{\mu}g/mL$) efficiently prevented protein oxidation induced by hydroxy radical as assayed by protein oxidation markers including protein carbonyl formation (PCO) and polyacrylamide gel electrophoresis. The effect of ethanol extracts of HS and HT on DNA cleavage induced by UV-photholysis of $H_2O_2$ using pBluescript M13+ plasmid DNA were investigated. These extracts significantly inhibited DNA damage induced by reactive oxygen species (ROS). Therefore, HS and HT extracts may be useful in the food industry as effective synthetic antioxidants.

• The Korean Journal of Food And Nutrition
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• v.3 no.2
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• pp.149-160
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• 1990

The soybean $\beta$-amylase ($\alpha$-1, 4-glucan maltohydrolase, EC 3.2.1.2) is composed of seven isozymes(I', I, II, III, IV, V and VI), and isozyme II and IV are the main components among these. The Purification of $\beta$-amylase isozymes from soybean whey were performed by ammonium sulfate fractionation, CM-Sephadex C-50 column chromatography, DEAE-Sephadex chromatography and Gel filtration. The resulted purity of $\beta$-amylase was throughly confirmed by electrophoresis, and then determined its isoelectric point and molecular weight. The results obtained were as follows, 1. Five active fractions of soybean p-amylase were derived on CM-Sephadex C-50 column chromatography. 2. Seven active bands of p-amylase isozymes were detected by isoelectric focusing gel electrophoresis, and their isoelectric points(I' to VI) were 5.07, 5.15, 5.25, 5.40, 5.55, 5.70 and 5.93, respectively. 3. Isozyme II and IV were main components of soybean $\beta$-amylase. 4. The molecular weights of both isozyme II and IV were determined to be 56,000 daltons by the result of SDS polyacrylamide gel electrophoresis. 5. Km values of main isozyme II & IV for amylopectin were determined to be 2.25 mg/ml, which suggest the same function of each isozyme.