• Korean journal of applied entomology
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• v.4
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• pp.25-28
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• 1965

The study was carried on a new disease of rice seedling which named 'Black rot of rice seedling'. None of papers on this disease was reported recently. The symptom of this disease was quite different from other seedling rot of rice plant. Submerged mycelial growth in water was black colored and it was surrounded whole surface of seed. Soil on which diseased seedlings were placed was black colored by this disease and the seedlings, finally stopped to grow within 3 em in height, and appeared with black rot symptom. Sporulation of the pathogen does not occurred under both of natural and artificial conditions. The mycelium appeared in dark color and with distinguished septation under the microscope. With those results it is easily recognized that the pathogen does not belong to those which causal organism:; of other seedling rot of rice plant like as Phycomycetes or Fusarium species. The study should be continued on identification of the causal organism. Favorable environments for the disease did not differ from other seedling rot of rice plant, and varietal resistance also did not significantly differ among the varieties used in this experiment. Dissemination of the disease was carried out not by planted seeds but by infected soil.

• BMB Reports
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• v.40 no.6
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• pp.845-852
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• 2007

The highly evolved flowers of orchids have colorful sepals and fused columns that offer an opportunity to discover new genes involved in floral development in monocotyledon species. In this investigation, we cloned and characterized the homologous PISTALLATA-like (PI-like) gene PhPI15 ($\underline{Ph}alaenopsis$ $\underline{PI}$ STILLATA # $\underline{15}$), from the Phalaenopsis hybrid cultivar. The protein sequence encoded by PhPI15 contains a typical PI-motif. Its sequence also formed a subclade with other monocot PI-type genes in phylogenetic analysis. Southern analysis showed that PhPI15 was present in the Phalaenopsis orchid genome as a single copy. Furthermore, it was expressed in all the whorls of the Phalaenopsis flower, while no expression was detected in vegetative organs. The flowers of transgenic tobacco plants ectopically expressing PhPI15 showed male-sterile phenotypes. Thus, as a Class-B MADS-box gene, PhPI15 specifies floral organ identity in orchids.

• Biomolecules & Therapeutics
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• v.24 no.5
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• pp.501-509
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• 2016

Shikonin, which derives from Lithospermum erythrorhizon, has been traditionally used against a variety of diseases, including cancer, in Eastern Asia. Here we determined that shikonin inhibits proliferation of gastric cancer cells by inducing apoptosis. Shikonin's biological activity was validated by observing cell viability, caspase 3 activity, reactive oxygen species (ROS) generation, and apoptotic marker expressions in AGS stomach cancer cells. The concentration range of shikonin was 35-250 nM with the incubation time of 6 h. Protein levels of Nrf2 and p53 were evaluated by western blotting and confirmed by real-time PCR. Our results revealed that shikonin induced the generation of ROS as well as caspase 3-dependent apoptosis. c-Jun-N-terminal kinases (JNK) activity was significantly elevated in shikonin-treated cells, thereby linking JNK to apoptosis. Furthermore, our results revealed that shikonin induced p53 expression but repressed Nrf2 expression. Moreover, our results suggested that there may be a co-regulation between p53 and Nrf2, in which transfection with siNrf2 induced the p53 expression. We demonstrated for the first time that shikonin activated cell apoptosis in AGS cells via caspase 3- and JNK-dependent pathways, as well as through the p53-Nrf2 mediated signal pathway. Our study validates in partly the contribution of shikonin as a new therapeutic approaches/agent for cancer chemotherapy.

• Journal of Plant Biotechnology
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• v.1 no.1
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• pp.61-68
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• 1999

Rapid accumulation of reactive oxygen species (ROS) and their toxic reaction products with lipids and proteins significantly contributes to the damage of crop plants under biotic and abiotic stresses. We have identified several stress activated alfalfa genes, including the gene of the alfalfa ferritin and a novel NADPH-dependent aldose/aldehyde reductase enzyme. Transgenic tobacco plants that synthesize alfalfa ferritin in vegetative tissues-either in its processed form in chloroplast or in the cytoplasmic non-processed form-retained photosynthetic function upon free radical toxicity generated by paraquat treatment and exhibited tolerance to necrotic damage caused by viral and fungal infections. We propose that by sequestering intracellular iron involved in generation of the very reactive hydroxyl radicals through a Fenton reaction, ferritin protects plant cells from oxidative damage. Our preliminary results with the other stress-inducable alfalfa gene (a NADPH-dependent aldo-keto reductase) indicate, that the encoded enzyme may play role in the stress response of the plant cells. These studies reveal new pathways in plants that can contribute to the increased stress resistance with a potential use in crop improvement.

• Journal of the Korean Chemical Society
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• v.45 no.4
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• pp.351-356
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• 2001

Planarization of the free-standing diamond film surface as smooth as possible could be obtained by using the hydrogen plasma etching with the diffusion of the carbon species into the metal alloy (Fe, Cr, Ni). For this process, we placed the free-standing diamond film between the metal alloy and the Mo substrate like a metal-diamond-molybdenum (MDM) sandwich. We set the sandwich-type MDM in a microwave-plasma-enhanced chemical vapor deposition (MPECVD) system. The sandwich-type MDM was heated over ca. 1000 $^{\circ}C$ by using the hydrogen plasma. We call this process as the hydrogen plasma etching with carbon diffusion process. After etching the free-standing diamond film surface, we investigated surface roughness, morphologies, and the incorporated impurities on the etched diamond film surface. Finally, we suggest that the hydrogen plasma etching with carbon diffusion process is an adequate etching technique for the fabrication of the diamond film surface applicable to electronic devices.

• Korean Journal of Agricultural Science
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• v.16 no.2
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• pp.163-168
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• 1989

Fourty-four isolates showed acetylene-reducing(nitrogenase)activity under the atmosphere of 89% Ar, 10% $C_2H_2$ and 1 % $O_{2{\cdot}}$, these nitrogen-fixing isolates characterized chemotaxonomically and their taxonomic status was disscussed; twenty-three isolates corresponded to Azospirillum. They were curved/spiral rods, gram negative, motile by a polar flagellum, and also utilized glucose in nitrogen free medild by a polar flagellum, and also utilized glucose in nitrogen free medium. but the cellular fatty acid composition and quinone system of these isolates showed quite different characteristics with reference strains. Therefore, the taxonomic status of this nitrogen-fixing bacteria is disscussed and a new species Azospirillum. Sixty forur isolates utilized C-l compounds such as methanol and formic acid. phenotypic and chemotaxonomic characteristics of methanol utilizing isolates were investigated and their taxonomic status was discussed; Twenty-one isolates corresponded to Hyphomicrobium and for the other regular rods and irregular rods utilizing isolates showed different cellular fatty acid composition. These isolates were grouped into 8 cluster analysis and similarity values based on correlation coefficients. Among these 8 clusters, two corresponded Pseudomonas and for the other were not decided.

• Journal of the Korea Society of Computer and Information
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• v.19 no.1
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• pp.203-213
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• 2014

In this study, we proposed a new model with ISOIA (Insect Search by Observation based on Insect Appearance) method based on observation by insect appearance to improve user satisfaction, and compared it with the ISBC and ISOBC methods. In order to test these three insect search systems with AHP method, we derived three evaluation criteria for user satisfaction and three sub-evaluation criteria by evaluation criterion. In the ecological environment, non-experts need insect search systems to identify insect species and to get u-Learning contents related to the insects. To assist the public the non-experts, ISBC (Insect Search by Biological Classification) method based on biological classification to search insects and ISOBC (Insect Search by Observation based on Biological Classification) method based on the inference that identifies the observed insect through observation according to biological classification have been provided. In the test results, we found the order of priorities was ISOIA, ISOBC, and ISBC. It shows that the ISOIA system proposed in this study is superior in usage and quality compared with the previous insect search systems.

• Korean journal of applied entomology
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• v.19 no.4 s.45
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• pp.221-227
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• 1980

A new disease of strawberry caused by Alternaria was found in Gim Hae, Gyougnam province, in July 1979. The symptoms of the disease occurred mainly on leaves as showing dark brown spots with circular to irregular, $5\~6mm$ in diameter. The pathogen was identified as Alternaria alternate (Fr.) Keissler which has not been described in Korea as a pathogen of strawberry disease. The common name of the disease was given as Gum un mum byung of strawberry. The conidia shape and size of this fungus varied considerably with culture media. The measurements of conidia and beak on corn meal agar were $20.1\times9.3{\mu}\;and\;4.0\mu$, respectively, which were shorter than those on strawberry leaf lesions in the field. Among 49 strawberry varieties tested, Morioca 16 and Robinson were highly susceptible to the disease by artificial inoculation and Catskill, Cyclone, Northwest, Merton princess, Juspa and Daehak I were moderately susceptible whereas 31 varieties were resistant. This fungus could also infect the leaf of Common garden sunflower, Double sunflower and Mexican sunflower among the 14 plants species tested.

• Korean Journal of Plant Resources
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• v.29 no.5
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• pp.588-597
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• 2016

Little attention has been paid to the functional aspect of the flower petal of Paeonia lactiflora, compared to that of its root. To determine the components of flower petal of Paeonia lactiflora, we conducted the Fourier transform ion cyclotron resonance (FT-ICR) MASS spectrophotometric analysis. We detected the 24 different types of ingredients from the 70% ethanol extracts of flower petal of peonia lactiflora cv. ‘Red Charm’. The main compounds were quercetin glucopyranosides, methyl gallate, paonioflolol and kaemperol glucopyranosides. We further tested its functional activity. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of the extracts was 87.9-90.4% at 0.1mg/ml. This result showed that these flower extracts have approximately 5-fold stronger antioxidant potential than a previous report with root extracts (Bang et al. 1999). The result of tyrosinase inhibition assay of Paeonia lactflora extract was almost similar to that of arbutin except significantly higher effect in the coral sunset extract at 0.1% concentration. Hyaluronidase inhibition assay showed 76.5% inhibition at 5% concentration of this flower extract, indicating that Peaonia lactiflora flower extracts have the major anti-inflammatory, anti-oxidant and brightening effects. Taken together, these results suggest these three Paeonia lactiflora species extracts might provide the basis to develop a new natural brightening agent.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.37 no.1
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• pp.91-96
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• 2011

Deficiency of collagen regeneration, denaturalization of fibers, increased melanin synthesis and reactive oxygen species are important factors inducing deterioration of healthy skin function. They induce freckles and decrease in skin elasticity. Vitamin C, vitamin A and their derivatives have been used as cosmetic ingredients for improvement of these problems but they have various problems. We have been developing the various derivatives of these ingredients. In this study, we investigated whitening effect of 3-o-cetyl-L-ascorbic acid (VCCE), a new vitamin C derivative. The VCCE inhibited melanogenesis in a dose dependent manner(44 % at $20\;{\mu}g/mL $) and tyrosinase expression. For 8 weeks, we also investigated skin brightening effect of VCCE on pigmented spots in UV-irradiated human skin. In results, VCCE showed a statistically significant skin whitening effect by mechanical and visual evaluation. Taken together, our findings suggest that the VCCE has potential benefits as an active ingredient for whitening cosmetics.