• Korean Journal of Microbiology
• /
• v.18 no.3
• /
• pp.123-132
• /
• 1980

Bacterial virus f2 and its RNA were examined to elucidate the mode of ozone utilizing sucrose density gradient analysis and electtron microscopic techniques. the inactivation kinetics of the virus f2 by ozonation showed that the viruses were inactivated during the first 5 sec of the reaction and were further inactivated at a slower rate during the next 10 min at 0.09 and 0.8mg/l ozone concentrations. The virus coat was broken by ozonation into many pieces of protein subunits and the adsorption of the viruses to the host pili was inversely related to the extent of the breakage of the virus. The viral RNA was released from the virus particles during ozone, but ozone inactivation of the RNA enclosed in the protein coat could not ruled out the possibility that the RNA was secondarily sheared by a reaction with the broken coat protein.

• Korean Journal Plant Pathology
• /
• v.14 no.6
• /
• pp.598-602
• /
• 1998

Twenty two rhizobacteria were isolated from the roots and rhizosphere of radish, carnation, potato and tomato. There isolates produced a fluorescent pigment in King's B medium and identified as Pseudomonas spp. These isolates colonized roots and rhizosphere of the host plants. In the study of cultural characteristics of the bacteria, the pH of the culture broth was changed from neutral (7.0) to alkali (8.8∼9.41) and the numbers of cells were increased from 106 to 108 after 40 hr of incubation in basal standard succinate medium. The salicylic acid production identified by pink color reaction were observed in 7 bacteria. Out of these 7 salicylic acid producing bacteria, only 2 strains of bacteria such as Pseudomonas fluorescens RS006, and Pseudomonas sp. EN401 were confirmed as salicylic acid producers by optical density measurement. Therefore, for screening of salicylic acid producing bacteria from the roots and rhizosphere, color reaction of the culture medium should be done in the first step, and then optical density measurement of culture extract should be made for the confirmation of salicylic acid production.

• Research in Plant Disease
• /
• v.27 no.1
• /
• pp.38-44
• /
• 2021

Xylella fastidiosa is the most damaging pathogen in many parts of the world. To increase diagnostic capability of X. fastidiosa in the field, the loop-mediated isothermal amplification (LAMP) and polymerase chain reaction (PCR) assay were developed to mqsA gene of citrate-synthase (XF 1535) X. fastidiosa and evaluated for specificity and sensitivity. Both assays were more robust than current published tests for detection of X. fastidiosa when screened against 16 isolates representing the four major subgroups of the bacterium from a range of host species. No cross reaction with DNA from healthy hosts or other species of bacteria has been observed. The LAMP and PCR assays could detect 10-4 pmol and 100 copies of the gene, respectively. Hydroxynaphthol blue was evaluated as an endpoint detection method for LAMP. There was a significant color shift that signaled the existence of the bacterium when at least 100 copies of the target template were present.

• Journal of Ceramic Processing Research
• /
• v.13 no.spc1
• /
• pp.6-9
• /
• 2012

Eu3+-doped RE2O3 (RE = Gd, Y and La) phosphors were prepared by solvothermal reaction method and their crystalline structure, phase transformation and surface morphologies were investigated by using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM). The obtained RE2O3:Eu3+ phosphors are nanocrystalline-sized. The luminescence properties of Eu3+ ions in different host materials, namely, Gd2O3, Y2O3 and La2O3 have been investigated. PACS number: 32.50.+d, 78.55.-m, 81.40.Tv.

• Biomedical Science Letters
• /
• v.10 no.4
• /
• pp.353-360
• /
• 2004

Eosinophils play an essential role in allergy reaction after parasite infection. To examine the immune reaction induced by eosinophils, we investigated the allergy reaction in BALB/c mice infected with Echinostoma hortense's metacercariae, as well as the effect of ketotifen, an anti-allergy drug, on eosinophil immune reaction in the villi of host intestine. The worm recovery rate was higher in ketotifen-treated mice than in untreated mice and the worms in ketotifen-treated mice survived longer than those in untreated mice. The antibody titer in the serum of ketotifen-treated mice was very low. Especially, Echinostoma hortense infection strongly increased serum IgE level and eosinophil infiltration into the villi of the mouse intestine. Ketotifen treatment suppressed eosinophil infiltration into the infected areas and inhibited IL-4 production. The reduced IL-4 production may be related with the reduction of IgE, IgG1 and IgG2 production. In conclusion, ketotifen inhibited eosinophil infiltration functioning in the allergy reaction induced by parasite infection and the expression of immunoglobulins and cytokines.

• Advances in materials Research
• /
• v.3 no.4
• /
• pp.227-232
• /
• 2014

$Ce^{4+}$, $Eu^{3+}$, $Tb^{3+}$ co-doped $Ca_3Si_3O_8F_2$ phosphor was synthesized via solid state reaction method using $CaF_2$, $CaCO_3$ and $SiO_2$ as raw materials for the host and $Eu_2O_3$, $CeO_2$, and $Tb_4O_7$ as activators. The luminescent properties of the phosphor was analysed by spectrofluorophotometer at room temperature. The effect of excitation wavelengths on the luminescent properties of the phosphor i.e. under near-ultraviolet (nUV) and visible excitations was investigated. The emission peaks of $Ce^{4+}$, $Eu^{3+}$, $Tb^{3+}$ co-doped $Ca_3Si_3O_8F_2$ phosphor lays at 480(blue band), 550(green band) and 611nm (red band) under 380nm excitation wavelength, attributed to the $Ce^{4+}$ ion, $Tb^{3+}$ ion and $Eu^{3+}$ ions respectively. The results reveal that the phosphor emits white light upon nUV (380nm) / visible (465nm) illumination, and a red light upon 395nm / 535nm illumination. RE ions doped $Ca_3Si_3O_8F_2$ is a promising white light phosphor for LEDs. The emission colours can be seen using Commission international de l'eclairage (CIE) co-ordinates. A single host phosphor emitting different colours under different excitations indicates that it is a potential phosphor having applications in many fields.

• The Plant Pathology Journal
• /
• v.16 no.6
• /
• pp.306-311
• /
• 2000

A new strain of Cucumber mosaic virus (CMV) from easter lily (Lilium longiflorum), Ly2-CMV, was identified and compared to the well-characterized Mf-CMV (subgroupⅠ) and LS-CMV (subgroupⅡ) by host reaction in several indicator plants, dsRNA analysis, serological property, RT-PCR analysis, restriction enzyme profile of the PCR products and nucleotide sequence of coat protein (CP) gene. Remarkable differences in symptoms of Ly2-CMV were found between Mf-CMV or LS-CMV in tobacco plants and Datura stramoinium. Ly2-CMV induced small necrotic ringspots on the inoculated leaves of Nicotiana tabacum cvs. Xanthi nc and Burley 21 and D. stramonium, and failed to infect these species systemically. Of the indicator plants tested, N. benthamiana only reacted with systemic infection by inoculation of Lr2-CMV. In experiments of dsRNA analysis, serology and RT-PCR of CP gene, Ly2-CMV was come within subgroupⅠ CMV. However, restriction enzyme analysis of the PCR products using MspⅠ showed that Ly2-CMV was distinct to Mf-CMV. The CP gene of Ly2-CMV contains 657 nucleotides, and the nucleotide sequence is similar to that of Mf-CMV. There is also a high degree of conservation between their putative gene products in Ly2-CMV and Mf-CMV, with five amino acid changes in the 218 amino acids of the CPs.

• Research in Plant Disease
• /
• v.14 no.3
• /
• pp.229-232
• /
• 2008

An isolate of Cucumber mosaic virus (CMV), designated as Cas-CMV, was isolated from Chinese aster (Callistephus chinensis) showing severe mosaic symptom, and its properties was compared to the well-characterized Fny-CMV (subgroup IA) and As-CMV (subgroup IB) by host reaction in several indicator plants, dsRNA analysis, RT-PCR analysis, and restriction enzyme profile of the PCR products. Cas-CMV differed markedly in their host reaction to Fny-CMV or As-CMV in Cucurbita pepo cv. Black beauty. In the zucchini squash, all strains induced chlorotic spot on inoculated leaves and mosaic symptoms on upper leaves. However, symptoms induced by Cas-CMV were developed lethal necrosis on the young plants 15 to 20 days after inoculation. In experiments of dsRNA analysis and RT-PCR analysis, properties of Cas-CMV was come within subgroup I CMV. Moreover, restriction enzyme analysis using HindIII of the RT-PCR products showed that Cas-CMV belong to a member of CMV subgroup IA.

• Journal of environmental and Sanitary engineering
• /
• v.4 no.1 s.6
• /
• pp.17-28
• /
• 1989

Having studied the production of monoclonal antibodies for developing a diagnosis medicine which shall be detected by a high-sensitivity test by using Rhodotorula rubra as a fungi-host which had been extracted through biochemical tests and follow-up examinations on Yeast-like fungi obtained from pulmonary tissues of pulmonary tuberculosis patients who had been in Kong ju National Tuberculosis Hospital from Jun. to Dec. in 1987, I. have gained such results as follows: 1. The fusion rate was influenced by feeder cell layers, cell density and time required to the cell fusion with cells in myelona subculture. 2. The fusion rate did not show any significant difference when the cell was applyed with two molecular weights, i.e., 1500 and 4000, of polyethylene glycol. 3. Fused cells after the addition of HAT selection media were bright and round, whereas unfused myelona cells and spleen cells were shrunk and granulated. 4. The cell fusion rate turned out to be about $57.2\%$(150 wells / 264 wells). 5. $10\%$(15 wells / 150 wells) of the positive reaction was detected in monoclonal antibody screening. 6. The titer which had reacted positively to Rhodotorula rubra fungal-host was 800 times in density after the gradual dilution of the produced monoclonal antibodies with Indirect ELISA method. 7. The Strongest specific reaction came out after the peroxidase labelled anti-human Immunogobulin had been applyed to Rhodotorula rubra for activating its nature after making drift with Carbonate-bicarbonate buffer (pH 9.6) and drying completely.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.26 no.4
• /
• pp.669-674
• /
• 1997

This study was attempted to express human lactoferrin gene that has importance as a functional additive in food industry. Lactoferrin has distinctive antibacterial properties. Also, a number of phy-siological roles have been postulated for the lactoferrin in the modulation of immune and inflamatory responses and as a growth factor. Since it did not show feasible growth inhibition by antimicrobial test against HLF, Pichia pastoris was selected the best lactoferrin expression host. HLF expression plasmid pHIL-SI was integrated into the genomic DNA of P. pastoris GSl15. The integration was confirmed not only with 2.4Kb fragment of HLF gene by PCR(polymerase chain reaction) product, but also with same size of specific signal by southern blotting. Among the various pichica transformants, the JY-1 cell showed a positive response for the expression of HLF by the immunoblotting anaysis. The recombinant HLF protein was started to be secreated at 48hr of culture and reached at the highest secreation level at 96hr.