• Journal of Life Science
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• v.15 no.4 s.71
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• pp.657-663
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• 2005

Collagenases are generally defined as enzymes that are capable of degrading the polypeptide backbone of native collagen under conditions that do not denature the protein. An extracellular collagenase-producing bacterial strain was isolated from kimchi and identified to be Bacillus subtilis JS-17 through morphological, cultural, biochemical characteristics and 16S rDNA sequence analysis. Optimum culture condition of Bacillus subtilis JS-17 for the production of collagenase was $1.5\%$ fructose, $1\%$ yeast extract, $0.5\%\;K_2HPO_4,\;0.4\%\;KH_2PO_4,\;0.01\%\;MgSO_4\cdot7H_2O,\;0.01\%\; MnSO_4\cdot4H_2O,\;,0.1\%$ citrate and $0.1\%\;CaCl_2$. The production of collagenase was optimal at $30^{\circ}C$ for 72 hr. A collagenase was isolated from the culture filtrate of Bacillus subtilis JS-17. The enzyme was purified using Amberlite IRA-900 column chromatography, Sephacryl S-300 HR column chromatography and DEAE-Sephadex A-50 column chromatography The purified collagenase has an specific activity 192.1 units/mg. The molecular weight of the purified enzyme was estimated to be 28 kDa by SDS-PACE. The purified collagenase has $100\%$ activity up to $55^{\circ}C$.

• Journal of the Microelectronics and Packaging Society
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• v.23 no.3
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• pp.57-61
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• 2016

In order to protect the solar cells from the moisture and oxygen, we evaluated the electrical and optical properties for the $Cu(In,Ga)Se_2$ (CIGS) solar cells which were prepared by the spray coating method. Generally, the EVA (ethylene-vinyl acetate) films are laminated to protect the CIGS flexible solar cells, which results in a high cost process due to complicated devices. In this study, we tried to prepare the protection layers of the flexible CIGS flexible solar cells by using spray coating method instead of conventional laminating films in order to reduce the device weight as well as the process time. The CIGS solar cells with spray coating method showed an enhanced efficiency than the before treated sample (2.77% to 2.93%) and relatively proper water vapor transmission rate of the solar cells about 62.891 gm/[$m^2-day$].

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.3
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• pp.527-533
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• 2002

In the screening of Korean traditional tea sources for the cellular lysosomal enzyme activity of peritoneal macrophage from mice, CT-0, a cold-water extract from Carthamus tinctorius L., showed the highest macro-phage-stimulating activity. CT-1-IIa-2-1, a purified macrophage-stimulation polysaccharide was obtained by a series of purification steps such as anion exchage chromatography with DEAE-Toyopearl 650M, gel permeation chromatography with Sepharose CL-6B, Sephacryl S-200, and HPLC with Superdex G-75. The molecular weight of homogeneous purified polysaccharide was estimated about 68 kDa. CT-1-IIa-2-1 consisted of xylose 27.44%, arabinose 16.14%, mannose 15.92% and glucose 14.47%. To measure acute toxicity, dose of 50, 100, 500, and 1000 mg/kg were intraperitoneally injected to ICR mice. The LD$\_$50/ was about 397 mg/kg.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.4
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• pp.373-383
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• 2019

The objectives of this study were to compare the protein expression patterns and degrees and identify the protein function of disomic addition lines (DAs) in Leymus racemosus, in order to improve the quality of wheat. Upon SDS-PAGE, L. racemosus showed two major protein bands whereas Chinese Spring (CS) had four major protein bands of high molecular weight. The DA(s) generally showed a similar protein expression pattern to that of CS, because 42 chromosomes were from CS and two chromosomes were from L. racemosus. However, only the L.r[J] line showed two protein bands of between 15 and 20 kDa, like L. racemosus. Image analysis based on 2-DE revealed that L.r[F] had the most upregulated protein spots, whereas L.r[N] had the least upregulated protein spots. For L.r[I], the frequency of the downregulated protein spots was higher than that of the upregulated ones. Using MALDI-TOF MS, the protein function was identified for each protein spot on the 2-DE polyacrylamide gel. The protein spots were classified into 11 groups according to protein function. Among the 11 groups, most protein spots of the DA(s) were identified as proteins related to metabolism. Additionally, unique protein spots of the DA(s) were related to abiotic stressors such as cold and heat. Those proteins are useful for improving wheat quality with resistance against abiotic stressors.

• Microbiology and Biotechnology Letters
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• v.32 no.2
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• pp.117-122
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• 2004

Bacillus sp. $\beta$-mannanase was purified by DEAE-sephadex ion exchange column chromatography. The specific activity of the purified enzyme was 21.57 units/$m\ell$ protein, representing an 95.33-folds purification of the original crude extract. The final preparation thus obtained showed a single band on SDS-polyacrylamide gel electrophoresis. The molecular weight was determined to be 38.9 kDa. Guar gum galactomannan was hydrolyzed by the purified $\beta$-mannanase, and then the hydrolysates was separated by activated carbon column chromatography and Sephadex G-25 gel filtration. The main hydrolysates were composed of D.P. (Degree of Polymerization) 5 and 7 galactomannooligosaccharides. To investigate the effects of guar gum galactomannooligosaccharides on in vitro growth of Bifidobacterium longum, B. bifidum, B. infantis, B. adolescentis, B. animalis, and B. breve, Bifidobacterium spp. were cultivated individually on the modified-MRS medium containing carbon source such as D.P. 5 and D.P. 7 galactomannooligosaccharides, respectively B. longum and B. bifidum grew up l0-fold and 9.8-fold more effectively by the treatment of D.P. 5 galactomannooligosaccharides, compared to those of standard MRS medium. Especially, D.P. 5 was more effective than D.P. 7 galactomannooligosaccharide on the growth of Bifidobacterium spp.

• Microbiology and Biotechnology Letters
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• v.38 no.2
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• pp.129-135
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• 2010

We described production of bioactive compounds from fungi grown on Korean ginseng-steaming effluents (GSE) for develop high-value added nutraceuticals from Korean GSE. Hansenula anomala KCCM 11473, which grew well in Korean GSE had high RNA content, and its optimal autolysis conditions were established to produce 5'-ribonucleotides (13.9~28.5 mg/g of biomass) at $55^{\circ}C$ and pH 5.0 for 24 h. 5'-Phosphodiesterase and adenyl deaminase were not effective in increasing the yield of 5'-ribinucleatides, but the yield of IMP increased significantly only after the addition of 1.0% adenyl deaminase. Saccharomyces cerevisiae showed the highest growth in the GSE medium. 267.1 mg of S. cerevisiae biomass was produced from 1 g of GSE solid and medicinal ginsenoside-$Rg_3$ contents was determined with 0.033 mg. Mucor miehei KCTC 6011 produced approximately 120 mg of chitosan per g-dry mycelium in 84 h at $25^{\circ}C$ when grown in the GSE (pH 8.0) supplemented with 0.5% yeast extract and 0.002% $CuSO_4$. Chitosan produced by M. miehei KCTC 6011 have deacetylated approximately 56% and its viscosity and molecular weight of the chitosan were 80 cps and $1.07\times10^3$ kDa, respectively. The chitosan at 1.5 mg/ml inhibited 73.9% of the mycelium growth of Rhizotonia solani in 60 h.

• Microbiology and Biotechnology Letters
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• v.48 no.2
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• pp.215-222
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• 2020

The marine microorganism PX-1, which can hydrolyze xylan, was isolated from coastal sea water of Jeju Island, Korea. Based on the 16S rRNA gene sequence and chemotaxonomy analysis, PX-1 was identified as a species of the genus Aestuariibacter and named Aestuariibacter sp PX-1. From the culture broth of PX-1, an extracellular xylanase was purified to homogeneity through ammonium sulfate precipitation and subsequent adsorption chromatography using insoluble xylan. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration chromatography estimated the molecular weight of the purified putative xylanase (XylA) as approximately 64 kDa. XylA showed xylanase activity toward beechwood xylan, with a maximum enzymatic activity at pH 6.0 and 45℃. Through thin-layer chromatographic analysis of the xylan hydrolysate produced by XylA, it was confirmed that XylA is an endo-type xylanase that decomposes xylan into xylose and xyloligosaccharides of various lengths. The K_m and V_max values of XylA for beechwood xylan were 27.78 mM and 78.13 μM/min, respectively.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.2
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• pp.144-150
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• 2013

Hybrid ceramic membrane (HCM) processes that combined ozonation with a ceramic membrane (CM) or a reactive ceramic membrane (RM), an iron oxide nanoparticles (IONs) incorporated-CM were investigated for membrane fouling control. Alumina disc type microfiltration and ultrafiltration membranes doped with IONs by sintering method were tested under varying mass fraction of IONs. Scanning electron microscope (SEM) images showed that IONs were well-doped on the CM surface and doped IONs were approximately 50 nm in size. Change in the pure water permeability of RM was negligible compared to that of CM. These results indicate that IONs incorporation onto CM had little effect on CM performance in terms of the flux. Natural organic matter (NOM) fouling and fouling recovery patterns during HCM processes confirmed that the RM-ozonation process enhanced the destruction of NOM and reduced the extent of fouling more than the CM-ozonation process by hydroxyl radical formation in the presence of IONs on RM. In addition, analyses of NOM in the feed water and the permeate showed that the efficiency of membrane fouling control results from the NOM degradation during HCM processes; leading to removal and transformation of relatively high contents of aromatic, high molecular weight and hydrophobic NOM fractions.

• Journal of Dairy Science and Biotechnology
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• v.21 no.2
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• pp.97-104
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• 2003

It is extremely important to destroy the antigenicity of milk proteins for dietetic treatment of infants with milk allergy. Enzymatic digestion of milk protein is not only effective for destroying antigenicity, but it also is less liable to alter the nutritive value. Bovine casein was hydrolyzed with eight different commercial proteases derived from bacterias or fungi, either individually or in combination to eliminate protein allergenicity. The average molecular weight of casein hyrdolysates determined by size exclusion chromatography is about 550${\sim}$2,300 dalton range. Antigenicity of the casein hyrdolysates was not detected by heterologous passive cutaneous anaphylaxis in guinea pig-rabbit antiserum system. The inhibition test on the enzyme-linked immunosorbent assay(ELISA) showed that the antigenicity of casein hydrolysates is lowed up to 1/8,000 than that of intact bovine casein. As the enzyme reaction was carried out by the combination of bacterial and fungal protease, casein hydrolysates showed much lower bitterness and antigenicity. It suggests that these hydrolysates will be applied to many kinds of foods including the development of hypo-allergenic infant formula.

• The Korean Journal of Pharmacology
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• v.31 no.2
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• pp.207-217
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• 1995

To investigate the functional and immunological properties of the Ca-release channel in the sarcoplasmic reticulum(SR) of the eel skeletal muscle, $[^3H]ryanodine$ binding, SDS gel electrophoresis, $^{45}Ca\;release$ studies, and immunoblot assay were carried out in the SR of the eel skeletal muscle. Maximal binding sites(Bmax) and $K_D$ values of $[^3H]ryanodine$ for Ca-release channel of the SR of the eel skeletal muscle were $19.44{\pm}1.40\;pmole/mg$ protein and $15.55{\pm}1.69\;nM$, respectively. $[^3H]Ryanodine$ binding to RyR was increased by calcium and AMP. The SR of the eel skeletal muscle has two high molecular weight bands on the SDS PAGE. The mobility of upper band was more slower than the single band of the rabbit skeletal muscle, and that of the lower band was similar with the single band of canine cardiac muscle. Vesicular $^{45}Ca-release$ was activated by calcium. Ca-induced $^{45}Ca-release$ was significantly inhibited by $MgCl_2(2\;mM)$, ruthenium red$(10\;{/mu}M)$ or tetracaine(1 mM), but not by high concentration of calcium itself. AMP-induced $^{45}Ca-release$ was slightly occurred only in the absence of calcium, it was not inhibited by $MgCl_2$ or ruthenium red. Caffeine also increased $^{45}Ca-release$ from the SR vesicles, but it was not affected by $MgCl_2$ or ruthenium red. Polyclonal Ab against rat skeletal muscle RyR is reacted with that of rabbit, but not reacted with that of the eel skeletal muscle. These results suggested that ryanodine receptor of the SR of the eel skeletal muscle is showing some similar properties with that of mammalian skeletal muscle, but might be an another isotype channel having two bands which is less sensitive to AMP, not cross-reacted with antisera against rat RyR, and not inhibited by high concentration of calcium.