• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.4
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• pp.659-666
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• 2006

Servo-motors are used as key components of automated system by performing precise motion control as accurate positioning and accurate speed regulation in response to the commands from computers and sensors. Especially, the linear brushless servo-motors have numerous advantages over the rotary servo motors which have connection with the friction induced transfer mechanism such as ball screws, timing belts, rack/pinion. This paper proposes an estimation method of unknown motor system parameters using the informations from the sinusoidal driving type linear brushless DC motor dynamics and outputs. The estimated parameters can be used to tune the controller gain and a disturbance observer. In order to meet this purpose high performance Digital Signal Processor, TMS320F240, designed originally for implementation of a Field Oriented Control(FOC) technology is adopted as a controller of the liner BLDC servo motor. Having A/D converters, PWM generators, rich I/O port internally, this servo motor application specific DSP play an important role in servo motor controller. This linear BLDC servo motor system also contains IPM(Intelligent Power Module) driver and hail sensor type current sensor module, photocoupler module for isolation of gate signals and fault signals.

• The Korean Journal of Mycology
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• v.16 no.2
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• pp.70-78
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• 1988

To obtain basic information for the genetic analysis and breeding of Flammulina velutipes, some factors affecting the release of protoplasts from the fungus were studied. Potato Dextrose peptone Agar medium was suitable for the growth of the mycelium and the protoplast formation of F. velutipes. The culture age for the high yields of protoplast was 5 days on PDPA. Few protoplasts were formed from the mycelium cultured on Mushroom minimum Media. The highest yield of protoplasts was obtained in enzyme solution containing Novozyme 234 plus cellulase CP at 10 mg $ml^{-1}$ concentration, while a half amount of protoplasts was obtained in enzyme solution containing Novozyme 234 only. The optimal reaction time of the mycelium in the Iytic enzyme mixtures was 3 hours. The best osmotic stabilizer for the protoplast formation of the mycelium was 0.6M sucrose without buffer at pH 6.2.

• The Korean Journal of Mycology
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• v.36 no.2
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• pp.189-195
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• 2008

When a homothallic ascomycete Aspergillus nidulans is exposed to visible light, cleistothecial development is inhibited. The light response of development in A. nidulans implies the existence of delicate regulation process including reception and translocation of light signaling and determination of development. Previously, mutants that could develop cleistothecia even in the presence of relatively intensive visible light were isolated and several complementation groups were identified. A gene that was able to complement the silA98 mutation, which was responsible for preferred cleistothecia development under visible light, was isolated from AMA-NotI genomic library. The silA gene retained in the 4.3 kb recovered genomic library DNA has an open reading frame (ORF) consisted of 2,388 bp nucleotides, interrupted by 3 introns and consequently encoding 795 amino acids. The putative SilA carries a ${Zn_2}{Cys_6}$ binuclear cluster motif at N terminus and shows high amino acid sequence similarity to Aro80p of Saccharomyces cerevisiae. Deletion mutants of silA showed a strong induction of sexual development under visible light, indicating that SilA is involved in the negative regulation of sexual development in response to the light.

• Journal of Microbiology and Biotechnology
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• v.27 no.11
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• pp.1971-1982
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• 2017

Piliated Lactobacillus rhamnosus (pLR) strains possess higher adherent capacity than non-piliated strains. The objective of this study was to isolate and characterize probiotic pLR strains in human fecal samples. To this end, mouse polyclonal antiserum (anti-SpaA) against the recombinant pilus protein (SpaA) of L. rhamnosus strain GG (LGG) was prepared and tested for its reactivity and specificity. With the anti-SpaA, a method combining the de Man, Rogosa, and Sharpe (MRS) agar plating separation and colony immunoblotting (CIB) was developed to isolate pLR from 124 human fecal samples. The genetic and phenotypic characteristics of the resultant pLR isolates were compared by randomly amplified polymorphic DNA (RAPD) fingerprinting, and examination of adhesion to Caco-2 cells, hydrophobicity, autoaggregation, and in vitro gastrointestinal tolerance. Anti-SpaA specifically reacted with three pLR strains of 25 test strains, as assessed by western blotting, immunofluorescence flow cytometry, and immunoelectron microscopy (IEM) assays. The optimized MRS agar separation plus anti-SpaA-based CIB procedure could quantitatively detect $2.5{\times}10^3CFU/ml$ of pLR colonies spiked in $10^6CFU/ml$ of background bacteria. Eight pLR strains were identified in 124 human fecal samples, and were confirmed by 16S RNA gene sequencing and IEM identification. RAPD fingerprinting of the pLR strains revealed seven different patterns, of which only two isolates from infants showed the same RAPD profiles with LGG. Strain PLR06 was obtained with high adhesion and autoaggregation activities, hydrophobicity, and gastrointestinal tolerance. Anti-SpaA-based CIB is a rapid and inexpensive method for the preliminary screening of novel adherent L. rhamnosus strains for commercial purposes.

• Microbiology and Biotechnology Letters
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• v.34 no.3
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• pp.196-203
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• 2006

Three slime-forming lactic acid bacteria were isolated from Kimchi and shown to produce viscous exopolysaccharides (EPS) in sucrose media. The isolated strains, GJ2, C3 and C11, were identified as Leuconostoc kimchii, Leuconostoc citreum and Leuconostoc mesenteroides, respectively, by examining their metabolic characteristics and determining their 16S rDNA sequences. Leu. kimchii GJ2, Leu. citreum C3 and Leu. mesenteroides C11 exhibited high viability (maintained initial viable cell count of $10^8$ CFU/ml) in 0.05 M sodium phosphate buffer (pH 3.0) for 2 h, in artificial gastric juice for 2 h and in 0.3% oxgall for 24 h. When tested, Leu. kimchii GJ2, in particular, displayed antimicrobial activity against pathogenic microorganisms. Leu. kimchii GJ2, Leu. citreum C3 and Leu. mesenteroides C11 produced 21.49 g/l, 16.46 g/l and 22.98 g/l EPS, respectively, in sucrose (5%) medium. The amount of purified EPS extracted from Leu. kimchii GJ2, Leu. citreum C3 and Leu. mesenteroides C11 was 14.61 g/l, 7.73 g/l and 4.77 g/l, respectively. Although the EPS produced by Leu. kimchii GJ2, Leu. citreum C3 and Leu. mesenteroides C11 differed in viscosity, TLC and HPLC analysis revealed that each contained only one type of monosaccharide, glucose. The average molecular mass of EPS produced by Leu. kimchii GJ2 was 306,606 Da.

• Journal of Plant Biotechnology
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• v.29 no.2
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• pp.99-104
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• 2002

Suppression subtractive hybridization (SSH) was used to isolate wound-induced cDNAs from wounded soybean. One of low-temperature-inducible cDNA, slti182 showed high homology with genes encoding 1-asparaginase. The full length cDNA of slti182, deginated GmASP1, is 1258 bp long and contains an open reading frame consisted of 326 amino acids. CmASP1 protein showed the highest identity (84%) with putative asparaginase from A. thaliana (AB012247), but it showed only 55% identity with another isoform of A. tathaliana (Z34884). The expression of GmASP1 during low temperature stress started to increase 3 hours after treatment, reached the maximum at 6 hour, and then decreased to the initial level at 48 hours. The amount of GmASP1 transcripts increased again when low-temperature-treated plants were transferred to room temperature, The present study suggests that GmASP1 may function to accelerate the protein synthesis which is important in the early response to low temperature.

• Korean Journal of Veterinary Service
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• v.36 no.3
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• pp.163-169
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• 2013

Both of avian influenza (AI) and Newcastle disease (ND) can cause mild to severe diease in poultry. In this study, clinical signs, macro, and micro lesions were studied. Eighteen six-week-old SPF chicks were divided into 4 groups (E1, E2, E3 and C1) and housed in different rooms of the isolation facility at CAVAC (Daejeon, Korea). The control group (C1) of 3 chicks was housed separately as uninoculated. Experimental groups (E1, E2 and E3) challenged with H9N2 and/or NDV. E1 group was challenged with 0.1 mL A/Kr/Ck/01310/01 (H9N2) $10^{5.6}$ $EID_{50}$ by intranasal, E2 group was challenged with 0.5 mL Kyojeongwon (KJW) $10^{5.0}{\sim}10^{6.0}$ $ELD_{50}$ by intramuscular, and E3 group was challenged with 0.1 mL A/Kr/Ck/01310/01 $10^{5.6}$ $EID_{50}$ by intranasal and 0.5 mL KJW $10^{5.0}{\sim}10^{6.0}$ $ELD_{50}$ by intramuscular 7 days after H9N2 challenge. In clinical signs and gross findings, E1 group showed 0% mortality, anorexia, and hemorrhage of proventriculus and thymus, E2 group showed 100% mortality within 3~5 days after challenge, anorexia, green diarrhea, hemorrhage of proventriculus, proximal esophagus and thymus, enlargement of kidney, and bronze liver, and E3 group showed 100% mortality within 24~36 hours after NDV challenge, depression, anorexia, green diarrhea, hemorrhage of proventriculus, spleen, and lung, enlargement of kidney, and reduction of thymus size and number. In histopathological examination, E1 group showed depletion and necrosis in bursa of Fabricius, thymus, and spleen, and E2 and E3 group showed severe lymphocyte depletion and necrosis with destruction of lymphoid organ structures. In conclusion, co-infection of H9N2 with ND virus causes acute disease with high mortality than single infection and the pathologic lesions were more severe.

• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.669-673
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• 2008

For the development of a biological control method against B. cereus in cheonggukjang, 20 Bacillus spp. were isolated from the naturally fermented baektae and heuktae cheonggukjang, identified by using 16S rDNA sequences. Among the isolated strains, Bacillus sp. SC-8 was selected using the B. cereus lawn cell assay as an antagonistic microorganism against B. cereus. The culture medium of Bacillus sp. SC-8 after 24 hr of incubation at $37^{\circ}C$ also evidenced a high level of antagonistic activity. In cheonggukjang fermented with the mixed culture of Bacillus sp. SC-8 and B. cereus, antagonistic effect against B. cereus was maintained during the fermentation of cheonggukjang, while its effect was reduced during storage at $4^{\circ}C$ due to the decrement of cell population of Bacillus sp. SC-8. In Bacillus sp. SC-15, which was utilized a control, antagonistic activity against B. cereus was not demonstrated on the lawn cell plate assay and culture medium, but its effects were detected in cheonggukjang. Therefore, the production of antagonistic substances of Bacillus spp. depends on the fermentative environment.

• Journal of Life Science
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• v.24 no.12
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• pp.1316-1324
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• 2014

Most beta-glucans obtained from various fruit bodies of mushrooms and mushroom mycelial cultures have high-molecular weight glycoproteins, conjugated with beta-glucans. We report that isoflavone-conjugated glycolproteins (designated as gluvone) were isolated and exhibited stronger anticarcinogenic activities. Agaricus blazei mycelia (ABM) was cultured in a liquid medium containing soybean flakes for 14 days. The liquid culture was autolyzed by incubating at $53^{\circ}C$ (pH 5.5) for 3 h. A crude glycoprotein (CGP) fraction with a cytotoxic effect on a mouse ascite cancer cell line (S-180) and a human breast cancer cell line (MCF-7) was isolated from the autolyzed ABM cultures by 80% ethanol treatment. Gluvone was isolated from the CGP with Sephadex G-75 column chromatography. It exhibited a stronger anticancer effect than CGP against the S-180 cell-induced female ICR mouse ascites carcinogenesis. Gluvone with 9,400 daltons was identified as a glycoprotein conjugated with isoflavone. According to HPLC and GC analysis, in conjunction with $^1H$-NMR spectral analysis, it contained 60% carbohydrates (glucose, fructose, and ribose), 31% protein, and 2% isoflavone (daidzein and genistein), which is a novel material. These results indicate that a strong anticarcinogenic gluvone was isolated from the autolyzed product of a submerged liquid culture of ABM, suggesting that autolysis could be a useful tool to produce antitumor agents.

• Applied Biological Chemistry
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• v.34 no.2
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• pp.134-141
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• 1991

In order to investigate the changes and characteristics of biochemical metabolic substances of soybean tissue culture during the cultural period, immature cotyledons were detached form the plant on 15th days after flowering and cultured in vitro for 3 weeks. The cultures were classified into embryogenic(EC) and non-embryogenic callus(NEC). A part of the EC lines were subcultured for another 3 weeks and classified into root forming(RFC), and shoot forming cultures(SFC). Another part of the EC lines were used for isolation of protoplasts, which were subsequently cultured in vitro for 4 weeks. The cultures were classified into embryogenic(PEC) and non-embryogenic callus(PNEC) derived from the protoplasts. The cultures of EC and PEC lines showed higher phenylalanine content and lower methionine content than those of NEC and PNEC. At organ differentiation stage, both cultures showed the content of aspartic acid decreased, while the other amino acids increased as a whole. The protein pattern analysis of the cultures revealed that EC and NEC lines contained distinctive polypeptides, with mass of ca. 18KD for EC and ca. 22KD for NEC respectively. The EC and PEC lines also showed high activity of peroxidase isozyme A(piA), while the RFC and SFC lines showed that of peroxidase isozyme B(piB).