• Applied Biological Chemistry
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• v.43 no.3
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• pp.169-173
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• 2000

For the development of enzyme detergent capable of effectively washing at low temperature, a bacterium producing alkaline protease was isolated from soil samples, and properties of the enzyme were investigated. The selected strain was Gram negative, rod shape$(0.6{\sim}0.7{\times}1.3{\sim}2.6\;{\mu}m\;in\;size)$ and motile. It had the degradation activity of aesculin, gelatin and casein, and was catalase-positive. The cell wall components was meso-DAP, and G+C mole contents was 43.3%. From these results, the strain was identified as Acinetobacter sp. KN-27. The activity of alkaline protease by this strain peaked with 3,300 D.U/mL after 36 hours in the liquid culture at $40^{\circ}C$. The optimal pH and temperature of the enzyme were pH 9 and $60^{\circ}C$, respectively. Alkaline protease produced by Acinetobacter sp. KN-27 has shown two active bands on the electrophoresis of native gel.

• International Journal of Industrial Entomology and Biomaterials
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• v.35 no.2
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• pp.63-70
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• 2017

Native fluorescent pseudomonas bacteria were isolated from rhizosphere soil of mulberry and were evaluated against powdery mildew. In vitro conidial germination study showed significant (P<0.05) variation in conidial germination by bacterial strains Pf1 and Pf3. Mildew incidence was significantly varied due to treatment with various pseudomonas strains in vivo. Significantly (P<0.05) less mildew incidence was in plants treated with the bacterial strain Pf1 (9.11%) followed by Pf3 (13.48%) controlling 69.40% and 54.75% respectively compared with untreated control. Similarly, mildew severity was least (8.51%) in plants treated with strain Pf1 followed by Pf5 (9.23%) and Pf3 (9.72%) controlling the severity by 84.51%, 77.01% and 71.96% respectively compared with control. The bacterial strains significantly influenced biochemical constituents such as chlorophyll, protein and soluble sugar content of the mulberry leaf. Similarly, bacterial strains significantly increased the activity of the peroxidase (PO) and Polyphenol oxydase (PPO) activity from $7^{th}$ day up to the $28^{th}$ day after treatment. The strain Pf1, Pf3 and Pf5 exhibited a marked enhancement in the peroxidase at different periods of infection. Significant (P<0.01) negative correlation was found between powdery mildew severity with phenol content ($R^2=0.67$) as well as peroxidase ($R^2=0.92$) and polyphenol oxidase ($R^2=0.72$) activity thus confirms induction of systemic resistance in mulberry by pseudomonas bacteria. The study shows scope for exploration of rhizosphere fluorescent pseudomonas bacteria for induction of systemic resistance in mulberry to contain powdery mildew disease effectively.

• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.587-592
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• 1989

A strain of alkalophilic Bacillus sp. YS-309 capable of producing large amount of $\beta$-galactosidase has been isolated from soil sample. Intracellular $\beta$-galactosidase was purified 6.9 folds by procedures including ammonium sulfate precipitation, DEAE-cellulose chromatography, gel-filtration, DEAE-Sephadex A-50 chromatography with over-all yield of 17.8%. The molecular weight of native enzyme was 205, 000 by HPLC, and SDS-polyacrylamide gel electrophoresis showed that the enzyme consisted of 4 identical subunits with a molecular weight of 56, 000.

• Journal of Microbiology and Biotechnology
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• v.20 no.9
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• pp.1295-1299
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• 2010

Recently, recombinant Streptomyces venezuelae has been established as a heterologous host for microbial production of flavanones and stilbenes, a class of plant-specific polyketides. In the present work, we expanded the applicability of the S. venezuelae system to the production of more diverse plant polyketides including flavones and flavonols. A plasmid with the synthetic codon-optimized flavone synthase I gene from Petroselium crispum was introduced to S. venezuelae DHS2001 bearing a deletion of the native pikromycin polyketide synthase gene, and the resulting strain generated flavones from exogenously fed flavanones. In addition, a recombinant S. venezuelae mutant expressing a codon-optimized flavanone $3{\beta}$-hydroxylase gene from Citrus siensis and a flavonol synthase gene from Citrus unshius also successfully produced flavonols.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.2
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• pp.188-199
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• 1996

The native ecological environment and aromatic constituents of Korean wild Codonopsis lanceolata and one Japanese strain were investigated to find Codonopsis lanceolata strains showing high aromatics, and to know regional differences among these strains. The results were as follows : There were no remarkable differences among the Korean wild C. lanceolata strains in ecological environments. Recovery yield of essential oils was highest in Togyusan strain with 0.009%. Difference in protein band patterns among these strains was not recognized, and peroxidase and esterase pattern changes were appeared in different collected regions at the leaf and root tissues. Major aromatic constituents were 11 kinds of aliphatic alcohols such as trans-2-hexenal, 1-hexanol, cis-3-hexanol, and trans-2-hexanol. And Togyusan strain, Sobaeksan strain, and Kayasan strain have the highest aliphatic alcohols of plant essential oils. In particular, BHT(butylated hydroxytoluene), one of the antioxidants, was detected in Chirisan strains.

• Journal of Sericultural and Entomological Science
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• v.45 no.1
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• pp.18-24
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• 2003

B. mandarina of Korean population apparently differs B. mori in isozyme analysis. Fourteen polymorphism occurred B. mandarina not in B. mori at 6 isozymes, Bph, Bes, Amy-hc, Ies, Ict-D, Ict-E. Korean population has shared with the Korean native strain of B. mori in B genotype of Bes, F of Amy-hc, n of Ict-E, M and S of Ict-H. These 5 genotype were known that detection only Korean native strains of B. mori. Nei's genetic distance based on the genotype of isozyme and hemolymph protein using 4 populations of B. mandarina varied from 0.0350 to 0.0624. The distances of 0.0350 is between Jinju and Chilgok population and between Jinju and Kosung population has the largest distances, 0.0624. In genus of Bombyx, B. mandarina and B. mori, genetic distance varied from 0.3822 to 0.5074. Phylogenetic tree obtained using the subprogram UPGMA of NTSYS represented that Bombyx devided two group, B. mandarina and B. mori. B. mandarina has genetic differences according to the population within the Korean peninsula, but that was not recognized genetic variation or divergence considering low values of genetic distance.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.3
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• pp.373-382
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• 1994

A bacterial strain No. 40, which produced extracellular endoglucanase, was isolated from the rumen of Korean native goals and identified to be a genus of Actinomyces sp. The optimum conditions for endoglucanase production in PY-CMC medium were initial pH of 7.0 and 4 days of cultivation at $39^{\circ}C$. When localization of endoglucanase activity of Actinomyces sp. was determined, 68% of the enzyme activity was found in the extracellular fraction, 11% of the activity was detected in the periplasmic space and the remaining activity was in the intracellular and cell-bound fractions. The maximal endoglucanase activity was observed at pH 5.0 and it was most s table at pH 5.0. The optimum temperature of this enzyme activity was $55^{\circ}C$, but enzyme activity was gradually lost at temperature above $60^{\circ}C$. The crude enzyme was activated by addition of 10 mM cysteine and 10 mM DTT. But it was inhibited by addition of 10 mM $Cu^{{+}{+}}$ and $Fe^{{+}{+}}$. This crude enzyme could digest carboxymethylcellulose (CMC), and degrade xylan, avicel, pNPG, and pNPC to a less extent.

• Korean Journal of Plant Tissue Culture
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• v.25 no.3
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• pp.201-206
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• 1998

To develop the fruits of cucumber (Cucumis sativus L.) producing high yields of superoxide dismutase (SOD), the MnSOD cDNA from pea (Pisum sativum) under the control of the cauliflower mosaic virus 35S promoter was introduced into cucumber using Agrobacterium tumefaciens (strain LBA 4404)-mediated transformation. The kanamycin-resistant shoots were selected on the selection medium containing MS basal salt, 1.0 mg/L zeatin, 0.1 mg/L IAA, 300 mg/L claforan, and 100 mg/L kanamycin. After 6 weeks of culture on the selection medium, the shoots were transferred to MS medium containing 0.2 mg/L NAA to induce roots. PCR analysis using the primers for neomycin phosphotransferase (NPTII) gene revealed that three plantlets were transformed. The fruits of one transgenic plant had approximately 3.2-fold higher SOD activity than those of non-transgenic plants. MnSOD isoenzyme band was strongly detected on native gel in fruits of transgenic plants.

• Korean Journal of Poultry Science
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• v.44 no.3
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• pp.189-198
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• 2017

This study was conducted to develop a new synthetic breed of Korean native chicken. The combining ability and reciprocal effects for production traits were estimated on 1,157 hens from a $5{\times}5$ diallel cross-mating design using grand parent stock (GPS) lines of Korean native chicken. Body weight, viability, age at first egg laying, egg weight, and hen-day egg production were measured and analyzed. The results showed that the general combining ability (GCA) of the survival rate during laying periods was -9.6 to 11.1, with the highest value obtained in the W strain. Additionally, the GCA of the body weight at 12 weeks was -209.7 to 162.2, with the highest value obtained in the F strain. The GCA for age at fist egg laying was estimated to be -2.8 to 3.7, while the GCA of egg weight was -0.91 to 0.96, and the GCA of hen-day egg production was -4.9 to 6.0. In the estimation of specific combining ability, the YW combination showed the highest survival rate, FW showed the highest body weight at 12 weeks, and GW showed the highest hen-day egg production. The reciprocal effects were significantly different among crosses for almost all productivity traits. In identical breeding combinations, differences in ability were observed when the maternal or paternal breeds were switched. The mean value based on combining ability was higher in WY, WF, and GW combinations for survival rate; GF, HG, and HF combinations for body weight at 12 weeks; and GW, YW, and FW combinations for hen-day egg production. It is concluded that the GF and HF combinations, which have excellent growth performance and moderate survival rate, are the most desirable paternal parent stock (PS) strains, and the GW and FW combinations, which have great laying performance and moderate body weight, are the most desirable maternal PS strains.

• Korean Journal of Poultry Science
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• v.44 no.2
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• pp.123-134
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• 2017

This study was conducted to establish new synthetic lines of Korean Native Chicken. We performed $5{\times}5$ diallel crossings with GPS lines of Korean Native Chicken for the selection of parent stock. The production traits including viability, body weight, age at first egg laying, egg weight, hen-day egg production, and hen-housed egg production were measured and analyzed for 25 crosses with 1,157 hens. The heterosis effects of these traits were also estimated. The results showed that the average survival rate during laying periods was 67.7% in the pure lines and 77.1% in the crosses. The 25 cross combinations were shown to be distinctly divided into three groups according to body weight; nine crosses in the high-weight group, 12 crosses in the medium-weight group and four crosses in the light-weight group. The average body weight at 12 weeks of age was $1,873.8{\pm}43.0g$ in the high group, $1,595.4{\pm}56.6g$ in the medium group and $1,152.7{\pm}24.7g$ in the light group, and $1,560.2{\pm}339.3g$ in the pure lines and $1,640.9{\pm}213.7g$ in the crosses. In terms of egg production performance, the age at first egg laying was $139.7{\pm}4.9$ days in the pure lines and $135.8{\pm}5.1$ days in the crosses. The average egg weight was $52.3{\pm}1.6g$ in the pure line and $53.0{\pm}1.6g$ in the crosses. The average hen-housed egg production from 20 to 40 weeks was $58.3{\pm}12.9$ eggs in the pure line and $69.2{\pm}10.4$ eggs in the crosses. The average heterosis effect was 16.9% for survival rate, 5.4% for body weight at 12 weeks, -2.7% for age at first egg laying, 1.3% for egg weight, and 14.3% for hen-day egg production. Generally, the heterosis effect for viability and egg production traits was higher than that for growth trait. On the basis of these results, it is expected that the selection of the HF combination, which had excellent growth performance, is the most desirable as the paternal strain, and the selection of GW and FW combinations, which had excellent laying performance, are preferable as the maternal strain.