• Journal of Microbiology and Biotechnology
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• v.2 no.1
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• pp.14-20
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• 1992

Some microorganisms isolated from soil, including some bacteria and fungi, were found to secrete an extracellular soymilk-clotting enzyme. Among them, an isolated fungus showed the highest soymilk-clotting activity and the strain was assigned to genus Penicillium based on its cultural and morphological characteristics, and designated as Penicillium sp. L-151K. Soymilk-clotting enzymes A and B produced by Penicillium sp. L-151K were purified by ammonium sulfate precipitation and chromatographies on Sephadex G-25, CM-Sephadex, Sephadex G-100 and phenyl-Toyopearl gel. The two purified enzymes A and B were found to be homogeneous by polyacrylamide gel electrophoresis at pH 9.5. The molecular weights of enzyme A and B were 24, 000 and 40, 000, respectively, by gel filtration on Sephadex G-100. Enzymes A and B coagulated soymilk optimally at $60^\circ{C}$ and were stable up to $50^\circ{C}$. Both enzymes were most active at pH 5.8 for soymilk coagulation, and were stable with approximately 80% of original activity from pH 3.0 to 5.0. Each enzyme was an acidic protease with an optimum pH of 3.0 for casein digestion. The soymilk-clotting efficiency of these enzymes was improved with $CaCl_2\;or\;MgCl_2$ when making soymilk-curd.

• The Korean Journal of Zoology
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• v.29 no.2
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• pp.141-158
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• 1986

A glutathione peroxidase from white rat (Wistar strain)erythrocytes was partially purified and characterized. In addition, localization of this enzyme in the liver was studied by histochemical method. A glutathione peroxidase was purified approximately 33.5-folds by ammonium sulfate precipitation, Sephadex filtration column and DEAE-Sephadex column chromatography. The optimum temperature of the crude glutathione peroxidase was $40^\\circC$, and the optimum pH was 7.5. This crude glutathione peroxidase was most stable at $30^\\circC$ and the values of Km and Vmax were calculated to be 8.5mM and 15.6 $\\mu$moles/min for glutathione, and 40 $\\mu$M and 10.5 $\\mu$moles/min for hydrogen peroxide, respectively. The molecular weight of this enzyme was estimated by Sephadex G-200 gel filtration to be approximately 90, 000. By electron microscopic examination, histochemical reaction products were microbodies that were prominent in the peripheral parts of the lobule. The reaction products exhibited round shapes, the diameter of which varied $0.2\\sim0.7 \\muM$ and their boundary membranes were not distint.

• Korean Journal of Animal Reproduction
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• v.12 no.3
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• pp.141-147
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• 1988

These experiments were carried out to develop new techniques for in vitro separation of x-and Y-bearing spermatozoa. The results obtained in these experiments were summarized as follows: 1. Following centrifugation of discontinuous percoll density gradient, populatin of spermatozoa increased progressively from low to high density. The highest concentration of spermatozoa was observed at the 4th fraction which included 36.6% of spermatozoa. 2. As increasing percoll concentration, the higher motility index was obtained and the highest motility index(74.2) was obtained at the 5th fraction. 3. The percentage of B-body bearing spermatozoa following percoll density gradient centrifugation was decreased from 39.7% to 25.6%. 4. The sperm population following chromatography by sephadex gel and percoll density gradient centrifugation was decreased in 1st, 5th and 6th fractions but the reverse was turn for 2nd, 3rd and 7th fractions, and the highest sperm concentration was observed at the 7th fraction which included 37.4% of spermatozoa. 5. Motility index of spermatozoa was increased from 77.6 to 79.4 after the sephadex gel filtration, however it was decreased at all fractions after percoll density gradient centrifugation. The lowest motility index(33.2) was obtained from the 7th fraction. 6. The rate of B-body bearing spermatozoa was shown the trend to decrease by the sephadex gel filtration and the trend was accelerated by the percoll density gradient centrifugation. The lowest percentage of B-body bearing spermatozoa, 12.0% was obtained from the 5th fraction.

• Microbiology and Biotechnology Letters
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• v.35 no.3
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• pp.250-254
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• 2007

Bacillus thringiensis strain 108 was isolated from soil and had nematicidal activity against second stage juvenile of plant root-knot nematode, Meloidogyne incognita. The strain 108, a rod shape, spore forming and Gram positive bacterium, produced lecithinase, catalase, and ${\delta}$-endotoxin. The strain 108 belongs to H serotype 3, Bacillus thuringiensis var. kurstaki. A nematicidal substance of the strain 108 was partially purified on Sephadex G-25 gel filtration, activated carbon adsorption, silica gel adsorption, and Sephadex G-10 gel filtration. $LC_{90}$ of the partially purified substance against M incognita was $1.2\;{\mu}g/ml$. The nematicidal substance was stable by heat treatment at $100^{\circ}C$ for 1hr, but was perfectly lost nematicidal activity after autoclave ($110^{\circ}C$, 30 min).

• Korean Journal of Microbiology
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• v.20 no.4
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• pp.183-188
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• 1982

The neurotoxin of Clostridium botulinum type B was purified from a liquid culture. The purification steps consist of ammonium sulfate precipitation of whole culture, treatment of Polymin P(0.15%, v/v), gel filtration on Sephadex G-100 at pH5.6 and DEAE-Sephadex charomatography at pH8.0. The procedure recovered 17% of the toxin assayed in the starting culture. The toxin was homogeneous by sodium dodecyl sulfate(SDS)-polyacrylamide gel electrophoresis and had a molecular weight of 163, 000. Subunits of 106, 000 and 56, 000 molecular weight were found when purified toxin was treated with a disulfide-reducing agent and electro phoresed on SDS-polyacrylamide gels.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.523.2-523
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• 1986

The hydrolysis of olive oil was attempted with immobilized C. rugosa lipase in the reverse phase solvent system. (i.e. immobilized wet particles is dispersed in continuous phase olive oil or organic solvents containing olive oil). Sephadex LH-20 and LH-60 were used as the supports that can be used in organic solvents. The water content of wet particles of sephadex LH-20 and LH-60 were about 72% (w/w) and 85% (w/w), respectively Both swollen gels with 0.05M buffers adsorbed about 18% of lipase dissolved. They were easily dispersed in liquid olive oil or in organic solvents. The effects of organic solvents on the stability and catalytic activity of the lipase have been examined. The results revealed that isooctane is superior to the other solvents examined for enzymatic fat spliting in reverse phase system. Kinetics of enzymatic hydrolys of olive oil by immobilized lipase has been investigated in a batch reactor. Effects of pH and temperature on the lipase were studied. The substrate concentration was influenced positively on the thermal stability.

• Microbiology and Biotechnology Letters
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• v.16 no.6
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• pp.438-442
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• 1988

The enzyme produced by Rhizopus japonicus was able to convert selectively ginsenoside-Rb$_1$which is the most abundant ginseng saponin, into ginsenoside-Rd which was known to be superior to ginsenoside-Rb$_1$pharmaceutically. The convertible enzyme was purified homogeneous from wheat bran culture of Rhizopus japonicus by ammonium sulfate fractionation and column chromatography of TEAE-cellulose, DEAE-Sephadex A-50, Sephadex G-150, Sepharose 2B. Specific activity of the purified enzyme was increased to a bent 96 folds and yield was appeared to be 11% of culture extract. Evidence for homogenity was obtained from polyacrylamide and SDS-polyacrylamide gel electrophoresis. Molecular weight of the enzyme was estimated about 88, 000 daltons by Sephadex G-l50 gel filtration and SDS-polyacrylamide gel electrophoresis, and it did not consist of any subunit.

• Microbiology and Biotechnology Letters
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• v.21 no.5
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• pp.446-452
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• 1993

The cholesterol oxidase produced from Bacillus sphaericus was purified and characterized. Through a series of purification procedures including DEAE-Toyoperal 650C, Sephadex G-200 and DEAE-Sephadex A-50 column chromatography, the purified enzyme was shown to have a specific activity of 0.179 units/mg protein having 31.8 fold purification and final yield of 12%. The molecular weight of the enzyme was estimated to be 47kDa and 47.tkDa by Sephadex G-200 chromatography and SDS-PAGE. The optimum temperature and pH for the enzyme were 30C and 6.0, respectively. The activity of the purified cholesterol oxidase was inhibited by Fe2+ and Hg+.

• Archives of Pharmacal Research
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• v.3 no.1
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• pp.31-36
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• 1980

Seeds or beans of 55 plants belonging to 31 families were screened by using several different types of red blood cells to find new lectins. In this paper, white kidney been (phaseolus vulgaris C.) was chosen to study biochemical properties of hemagglutinating proteins(lectins). An anion exchanger, DEAE Sephadex A-50, and polyacrylamide disc gel electrophoresis were main techniques used. From three main fractions eluted by stepwise NaCl gradient in 25mM Tris-HCI buffer on DEAE Sephadex column, principal lectin was identified.

• BMB Reports
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• v.35 no.2
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• pp.199-205
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• 2002

An anticoagulant protein was purified from the edible portion of a blood ark shell, Scapharca broughtonii, by ammonium sulfate precipitation and column chromatography on DEAE-Sephadex A-50, Sephadex G-75, DEAE-Sephacel, and Biogel P-l00. In vitro assays with human plasma, the anticoagulant from 'S. broughtonii, prolonged the activated partial thromboplastin time (APTT) and inhibited the factor LX in the intrinsic pathway of the blood coagulation cascade. But, the fibrin plate assay did not show that the anticoagulant is a fibrinolytic protease. The molecular mass of the purified S. broughtonii anticoagulant was measured to be about 26.0kDa by gel filtration on a Sephadex G-75 column and SDS-PAGE under denaturing conditions. The optimum activity in the APTT assay was exhibited at pH 7.0-7.5 and $40-45^{\circ}C$ in the presence of $Ca^{2+}$.