• Journal of Agricultural Extension & Community Development
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• v.7 no.1
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• pp.181-191
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• 2000

This experiment was conducted to find out the effects of mushroom cultivation on ozone susceptibility. The mushroom media in cultivation became softening well without bad Knell when it was soaked for 120 hours. The mushroom media softening on cultivating of oyster mushroom was good and fast when the concentration of gas condition ozone is high. The concentration of gas condition ozone must control at less than 0.02 ppm at the innoculation room, 0.03 ppm at the incubating room, must not use at the sprouting mom, less than 0.02 ppm at the growing room respectively. Also at the growing room, it removes the smell of mushroom, so has a protective effects of coming into mushroom fees and disease. When the concentration of 0.02 ppm liquid condition ozone was sprinkled, it was very useful in disease protection If it was input, the storage period of mushroom fruiting body was prolonged.

• Korean Journal of Agricultural Science
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• v.23 no.1
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• pp.80-89
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• 1996

The expression and secretion of human lactoferrin (hLf) in Sacclnromyces diastaticus were performed. 1. For the secretion of hLf in yeast, recombinant plasmid pYEGLf was constructed using promoter, secretion signal sequence of glucoamylase I gene (STA1) and transcriptional terminator of GAL7 gene. 2. Each correct recombinant plasmid was selected by mini-preparation of plasmid DNA from E coli transformant and restriction enzyme digestion analysis. The selected plasmids, pYEGLf, were transformed into S. diastaticus YIY345 as a expression host, respectively. 3. Western blot analysis using rabbit anti-hLf was carried out to identify expressed hLf. Positive signals were shown in culture supernatant of pYEGLf transformant. 4. About $100{\mu}g-1mg$ of concentrated culture supernatant of positive clone were loaded on paper disc and tested for the antimicrobial activity against E coli. However, no activity was observed. We concluded that this fact results from low concentration of hLf secreted from yeast, compared with the fact that MIC of hLf is as high as $3mg/m{\ell}$. Therefore, the purification of secreted hLf may be require to investigate the antimicrobial activity. From this study, the feasibility of low-cost production of sufficient quantities of human lactofferin for nutritional and therapeutical applications were suggested.

• Childhood Kidney Diseases
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• v.2 no.2
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• pp.169-177
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• 1998

Purpose : Renal duplication is a common occurrence, and the range of ureteral and renal anomalies draining the two poles of the duplex kidney leads to a variety of clinical presentations. Method : A series of 61 children with duplicated systems was studied retrospectively who were admitted during last 12years. Results : Of the children $60.6\%$ were accompanied with urologic anomalies that required surgical treatment, and most children initially were presented with urinary tract infection. $42.6\%$ of children were either diagnosed incidentally during evaluation of other non-urologic disease or during follow-up evaluation of abnormal antenatal renal sonogram. Conclusion : From our point view, children with history of abnormal antenatal renal sonogram, or with symptoms such as urinary tract infection, hematuria, abdominal pain should be evaluated radiologially fully to confirm further abnormality and accompanied complications. And routine follow-up using abdominal ultrasonogram, VCUG, and urine culture should be used to prevent and detect early treatable complications.

• Research in Plant Disease
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• v.12 no.3
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• pp.254-259
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• 2006

Bacillus spp. isolated from mushroom medium wastes were evaluated for their biocontrol potentials on control of Sclerotinia rot of lettuce. The Bacillus isolates were more effectively obtained from waste suspension when directly added into nutrient agar(NA) medium than plating on the agar medium. Totally 42 isolates obtained from the wastes B23 and B42 showed highest antifungal activity against eight fungal pathogens such as Sclerotinia sclerotiorum, Rhizoctonia solani, Pythium ultimum, Phytophthora capsici, Fusarium oxysporum, Colletotrichum gloeosporioides, Cladosporium cucumerinum, and Botrytis cinerea and B23 and B42 were finally selected for further studies. Optimal concentration of the isolates was $10ml(10^7cfu/ml)$ to suppress the Sclerotinia rot of lettuce. Supplements such as starch, glycerol, and egg-yolk successfully maintained the bacterial population for 30 days in vitro and increased bio-control potentials against the disease. The bacterial isolate B23 alone showed 72% control value, furthermore it presented 95% control value when supplemented with 0.2% of starch, glycerol, and egg-yolk. The promising Bacillus isolates B23 and B42 were identified as Brevibacillus brevis and Bacillus stearothermophillus, respectively, based on morphological and physiological characteristics according to API database.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.847-858
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• 2015

Bacillus amyloliquefaciens GR4-5 was isolated from the rhizosphere soil of Korean ginseng and displayed broad-spectrum suppression of ginseng root rot pathogens. The survivability of B. amyloliquefaciens GR4-5 in soil was investigated under three different conditions; indoor, outdoor - of which soil was put in 14 mL tube after treatment - and field environments. Soil samples were collected over a four-week period from three experimental designs, and assessed for 16S rRNA gene copy number by quantitative polymerase chain reaction (qPCR). In outdoor condition, the 16S rRNA gene copy number of Bacillus spp. was 8.35 log copies g $soil^{-1}$ immediately after the GR4-5 treatment. Two weeks later, the 16S rRNA gene copy number of Bacillus spp. (6.70 log copies g $soil^{-1}$) was similar to that of the control (6.38 log copies g $soil^{-1}$). In indoor condition, the 16S rRNA gene copy number of Bacillus spp. maintained in a certain level for a longer period than those in outdoor and field. The 16S rRNA gene copy number of Bacillus spp. in field experiment was reduced faster than that of outdoor condition. Our results show that B. amyloliquefaciens GR4-5 can survive in bulk soil for 1 week, indicating its potential use as a biocontrol agent following 7 day application intervals. This study presents that outdoor microcosm system design could be a useful method to assess easily the survivability of beneficial microorganisms.

• Korean Journal of Plant Tissue Culture
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• v.22 no.3
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• pp.175-182
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• 1995

Rice is one of the most successful monocot in regenerating fertile and genetically stable transgenic plants. However there is no report of a rice line developed in Korea that can be used for regeneration of fertile and genetically stable transformants. In this paper we first demonstrate that a Korean variety Nakdongbyeo, is suitable to obtain transgenic rice plants. Protoplasts from embryogenic suspension cultures were co-transformed with HPT (hygromycin phosphotransferase) and GUS ($\beta$-glucuronidase) genes in separate plasmids in the presence of PEG (polyethylene glycol). In 5 independent experiment, the average frequency of calli showing hygromycin resistance were 1.73%. Plantlets were regenerated from the Hy $g^{R}$ calli. The average efficiency of plantlet regeneration was apprbximately 27%. Based on the GUS activities of hygromycin resistant calli, ca.35% of the resistant calli carried active GUS genes. The R0 transgenic plantlets were grown to maturity and Rl seeds were obtained. By examining the in siぉ activity of GUS in Rl seeds and seedlings, we confirmed that the GUS transgene driven by a CaMV 35S (cauliflower mosaic virus) promoter showed proper expression patterns. We also confirmed Mendelian segregation of the HPT transgene in the Rl generation.n.

• Korean Journal of Plant Tissue Culture
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• v.27 no.6
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• pp.453-459
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• 2000

Three rice (Oryza sativa L. var Dong-Jin) mutants (DTR1, DTR2, DTR3) resistant to S-methyltryptophan (5MT) were selected by mutagenized M3 seeds. The frequency of chlorophyll mutations induced by the EMS (0.2%) treatment performed 2 hours after flowering is clearly higher than that induced by other treatments in M1 generation. Progeny obtained from the self-pollinating of 5MT-resistant lines segregated with 3 : 1 of resistant to sensitive ratio. Furthermore, the ratio of homozygote to heterozygote in 5MT-resistant plants of the M4 generation was 1：2. These results show that 5MT resistance was inherited as a single dominant nuclear gene. The resistance was also expressed in callus derived from seeds. Total free amino acid content in homozygous seeds of DTR1 and DTR2 showed about 1.7 fold-increased compared to the wild-type seeds. In particular, the levels of phenylalanine and Iysine were, respectively, 6.2 and 3.2 times higher than those in the wild-type seeds. However, seeds of DTR3 had lower levels of free amino acid than the wild-type seeds. This result indicate that these mutants as a significant step towards the production of new rice with balanced amino acid content.

• Journal of Sericultural and Entomological Science
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• v.38 no.1
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• pp.42-47
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• 1996

To investigate the host range determining factors of nuclear polyhedrois virus (NPV), Autographa california NPV and Bombyx mori NPV were coinfected into the two different cell lines, BmN-4 and Sf-9. The recombinant baculoviruses, RecS-A6 and RecB-727 which have an expanded host range, were isolated from Sf-9 and BmN-4 cell lines, respectively. The molecular biological characteristics of the recombinant baculoviruses were investigated. The pathogenicity of RecB-727 was similar to that of wild type BmNPV, while the pathogenicity of RecS-A6 was relatively lower than that of wild type BmNPV. The restriction enzyme digestion patterns of parental viruses and recombinant viruses showed that the recombinant virus has an expanded host range by genetic recombination. Southern blot analysis revealed that the p10 gene of RecB-727 was derived from AcNPV genomic DNA, while RecS-A6 has p10 gene of BmNPV in a viral genome. To investigate the host range expansion mechanism of recombinant baculovirus, HindIII-SacI 0.6 kb DNA fragments of RecS-A6 and RecB-727 were cloned and sequenced. The results showed that of wild type BmNPV helicase gene, suggesting that the expanded host range of recombinant baculoviruses was due to the insertion of BmNPV helicase gene into AcNPV viral genome.

• Journal of the Korean Wood Science and Technology
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• v.39 no.6
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• pp.469-480
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• 2011

In this study, to determine the ligninase activity related to the PCBs degradation of Ceriporia sp. ZLY-2010, the protein contents and manganese peroxidase (MnP) and laccase activities during cultivation on shallow stationary culture (SSC) medium were observed. 4 PCB congeners were selected depending on the number of chlorine substituted on biphenyl. Furthermore, to examine the effects of cytochrome P450 monooxygenase, the inhibition of cytochrome P450 monooxygenase was evaluated by measuring the biodegradation rate when inhibitor such as 1-aminobenzotriazole was added. The extracellular protein contents were affected by PCB congeners in culture media. The total protein in the culture medium showed the biggest differences between the samples containing 2,2',4,4',5,5'-hexachlorobiphenyl and the control. On the other hand, MnP and laccase activity showed dominant increases within samples containing 4,4'-dichlorobiphenyl and 2,3',4',5-tetrachlorobiphenyl. Cytochrome P450 monooxygenase was inhibited by adding inhibitor, 1-aminobenzotriazole in low concentration. Only 2.73% of 2,3',4',5-tetrachlorobiphenyl was degraed on day 1, and biodegradation of 2,2',4,4',5,5'-hexachlorobiphenyl was inhibited as well, showing about 20% of biodegradation rate.

• Journal of fish pathology
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• v.11 no.2
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• pp.97-104
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• 1998

Since 1989, mass mortality has repeatly occurred in cage-cultured sevenband grouper, Epinephelus septemfasciatus along the southern coast of Korea in the summer season and usually reached over 80% within a few months. Diseased fish showed the clinical signs of anorexia, dark coloration, loss of eqilibrium, spinal swimming behaviour, vertebral deformity and inflation of swim bladder. Histopathologically, necrosis and/or vacuolation of the nerve cells in the brain and retina were observed. We previously reported that the causative agent was filtrable. The causative agent was not culturable in various fish cells; RTG-2, CHSE-214, BF-2, EPC and FHM. However, electron microscopic observation revealed unenveloped icosahedral viral particles with about 30 nm in diameter in the cytoplasm of nerve cells of the brain. The characteristics of the virus was tested by an artificial infection with the filtrate of the homogenate of diseased fish. The pathogenicity of the virus was retained after treatment with ether or heat ($50^{\circ}C$, 30 min) but partly lost by pH 3 or 11 treatment. These results suggest that the causative agent are similar to the fish nodavirus. In order to compare the causative agent with a fish nodavirus, Striped Jack Nervous Necrosis Virus (SJNNV), a polymerase chain reaction (PCR) was performed with primers specific to SJNNV. As a result, about 430 by PCR products were detected from the brain and the eye of both naturally and artificially infected sevenband grouper. All these results represent that the mass mortality in the cultured sevenband grouper is caused by the infection of a nodavirus similar to SJNNV and this is the first report of a fish nodavirus from the cultured sevenband grouper in Korea.