Electrostatic spinnings were performed with the solutions of PAN/DMF to be nanofiber webs. The diameter of the fibers ranged from 200 nm to 1000 nm depending on the PAN concentration and on the applied DC voltage. The nanofibers were oxidatively stabilized and subsequently carbonized up to 1000℃ with carbonization yield of 40%. The bulk electric conductivity of the carbonized web increased form 6.8×10-3S/cm to 1.96 S/cm while the carbonizaton temperature increased from 700℃ to 1000℃.

Short pitch fibers were prepared from petroleum based isotropic precursor pitch by melt-blown technology. The pitch fibers were stabilized in oxidizing condition, followed by steam activations at various conditions. The fiber surface and pore structures of the activated carbon fibers (ACFs) were respectively characterized by using SEM and applying BET theory from nitrogen adsorption at 77 K. The weight loss of the oxidized fiber was proportional to activation temperature and activation time, independently. The adsorption isotherms of the nitrogen on the ACFs were constructed and analyzed to be as Type I consisting of micropores mainly. The specific surface area of the ACFs proportionally increased with the weight loss at a given activation temperature. The specific surface area was ranged 850~1900 m2/g with pores of narrow distribution in sizes. The average pore size was ranged 5.8~14.1 a with the larger value from the more severe activation condition.

Petroleum based isotropic pitch was spun into short fiber by melt-blown spinning technology. The processing parameters chosen were air velocity, die temperature, and throughput rate of the pitch within the ranges of experimental tolerances. The fiber diameter was reduced to 6μm by increases of hot air velocity, and spin die temperature. Also, the fiber diameter was strongly dependent on the throughput rate of the pitch and jet speed of hot air through the spinnerets. Even fibers with 10μm diameter were produced at throughput rate of 0.17g/min·hole and at die temperature of 290℃.

A petroleum-based isotropic pitch fiber spun by melt-blown method was oxidized in air flow at various conditions. The oxidized pitch fiber obtained was tested for its infusibility and its elemental composition during the process of stabilization. The structural changes were traced by using solvent solubility, FT-IR spectroscopy, and elemental analysis. The samples showed a gradual increase in weight with increasing the oxidization temperature. The weight gain of sample oxidized at 320℃ for 10 min was about 4.5%. The concentration of the pyridine and toluene soluble fraction decreased with an increase in stabilization temperatures. The oxygen uptaken in the stabilization process converted aliphatic side chains into the carbonyl groups. As stabilization proceeded, the more ether and carboxylic acid groups were formed through the oxidations of aldehyde and primary alcohol, and then the carboxylic acid was dehydrated to be aromatic anhydride.

Background : Astilboides tabularis (Hemsl.) Engl. is a perennial herbaceous plant, distributed in the northern high mountains of the Korean peninsula and China. It is an excellent ornamental plant currently at risk of overharvesting and therefore, is designated as an endangered wild plant Class II by the Ministry of Environment. Physiological research on A. tabularis has not be reported. Therefore, in this study, using A. tabulari extracts, antioxidant and Anti-inflammatory effects were determined. Methods and Results : The antioxidant and free radical scavenging activities of A. tabularis extracts were evaluated using DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. The results showed that the ethyl acetate fraction of A. tabularis possesses potent DPPH radical scavenging activity (2.90±0.08㎍/㎖), similar to the scavenging activity of ascorbic acid (2.19±0.06㎍/㎖), and better than the powerful antioxidant α-tocopherol (10.60±0.40㎍/㎖) as well as BHA (butylatedhydroxy anisole)(6.12±0.27㎍/㎖). The ethyl acetate fraction possessed a significantly higher concentration of total phenolic (549.70±2.72㎎GAE/g) and flavonolic content (154.58±1.04㎎QE/g). It was also found that the ethyl acetate fraction exhibited high reducing power and inhibition of ROS (Reactive Oxygen Species) formation. Different fractions of A. tabularis were tested for anti-inflammatory activity using LPS stimulated Raw 264.7 cells. The n-hexane and ethyl acetate fractions exhibited a high inhibitory effect on NO (Nitrite oxide) production (22.43±1.06%, 19.30±0.45%, respectively) at 200㎍/㎖ concentration. The mRNA of IL-1β, iNOS and COX-2 gene expression was decreased by treatment with the ethyl acetate fraction. These results showed that A. tabularis extracts can be used as natural substances to control inflammation. Conclusion : These result showed that A. tabularis extracts can be used in a variety of antioxidant and other functional product research and development processes as valuable natural materials.

Background : Curcuma longa L., in the family Zingiberaceae, is distributed in tropical and/or sub-tropical regions mainly in India and China. This species is commonly called turmeric, powder is used as medicinal herbs and/or flavor enhancer. It has been cultivated in southern region mainly Jindo. However, it might be possible to extend cultivation regions due to rise in average temperature. In order to select superior lines based on agronomic characteristics, we analyzed multivariate and estimated selection effects from C. longa germplasm. Methods and Results : The C. longa germplasm were cultivated in an experimental field located in Eumseong, NIHHS, RDA. The harvested roots were investigated in agronomic characteristics included in yield and then considered its relationship among the 9 germplasm by multivariate analysis method. Results from principal component analysis (PCoA) showed that it represented 70.00% and 80.44% accumulated explanation from four and five principal compounds (PC). PCoA was conducted from 9 agronomic characteristics and then correlation coefficient has been showed by analysis between each main component value and agronomic characteristics. Value of the first PC was 2.25, 24.96% explanation of total dispersion, plant height, number of rootlet and weight of rootlet were correlated with a somewhat higher level as 0.41, 0.43 and 0.52. Value of the fifth PC was 0.94, 10.43% explanation of total dispersion, the number of shoots was correlated with a higher level as 0.87. Selection effects with outstanding candidate lines including higher lines were estimated at 126.13% in yield. Conclusion : These data on multivariate based on agronomic characteristics will be give us invaluable breeding information by selection of superior lines.

Rice transformation method using A. tumefaciens has already been widely used to generate transgenic plants, the transformation rate is still low in most Korean elite cultivars. We made several modifications of the standard protocol especially in the co-cultivation step to improve the efficiency of the rice transformation. The co-culture medium was modified by the addition of three antioxidant compounds (10.5㎎/ℓ L-cysteine, 1mM sodium thiosulfate, 1mM dithiothreitol) and of Agrobacterium growth-inhibiting agent (5㎎/ℓ silver nitrate). Co-cultivation temperature (23. 5℃ for 1 day, 26.5℃ for 6 days) and duration (7 days) were also changed. The plasmid of pMJC-GB-GUS carrying the GUS reporter gene and the bar gene as the selectable marker was used to evaluate the efficiency of the transformation. After co-cultivation, a high level of GUS gene expression was observed in calli treated with the modified method. It is likely that those newly added compounds helped to minimize the damage due to oxidative bursts during plant cell-Agrobacterium interaction and to prevent necrosis of rice cells. And the transformation rate under the modified method was also remarkably increased approximately 8-fold in Heungnambyeo and 2-fold in Ilmibyeo as compared to the corresponding standard method. Furthermore, we could produce the transgenic plants stably from Ilpumbyeo which is a high-quality rice but its transformation rate is extremely low. Transformation and the copy number of transgenes were confirmed by PCR, bar strip and Southern blot analysis. The improved method would attribute reducing the effort and the time required to produce a large number of transgenic rice plants.

Rice transformation method using A. tumefaciens has already been widely used to generate transgenic plants, the transformation rate is still low in most Korean elite cultivars. We made several modifications of the standard protocol especially in the co-cultivation step to improve the efficiency of the rice transformation. The co-culture medium was modified by the addition of three antioxidant compounds (10.5㎎/ℓ L-cysteine, 1mM sodium thiosulfate, 1mM dithiothreitol) and of Agrobacterium growth-inhibiting agent (5㎎/ℓ silver nitrate). Co-cultivation temperature (23. 5℃ for 1 day, 26.5℃ for 6 days) and duration (7 days) were also changed. The plasmid of pMJC-GB-GUS carrying the GUS reporter gene and the bar gene as the selectable marker was used to evaluate the efficiency of the transformation. After co-cultivation, a high level of GUS gene expression was observed in calli treated with the modified method. It is likely that those newly added compounds helped to minimize the damage due to oxidative bursts during plant cell-Agrobacterium interaction and to prevent necrosis of rice cells. And the transformation rate under the modified method was also remarkably increased approximately 8-fold in Heungnambyeo and 2-fold in Ilmibyeo as compared to the corresponding standard method. Furthermore, we could produce the transgenic plants stably from Ilpumbyeo which is a high-quality rice but its transformation rate is extremely low. Transformation and the copy number of transgenes were confirmed by PCR, bar strip and Southern blot analysis. The improved method would attribute reducing the effort and the time required to produce a large number of transgenic rice plants.

During the last decade, considerable progress has been made to understand the molecular mechanisms of M. grisea infection in rice plants and 10 rice blast R genes have been identified and characterized via map-based cloning methods. In case of rice germplasm, the genetic backgrounds of each germplasm accessions are not uniform and the evaluation for pathogenicity is difficult. To solve these problems, we applied the single resistance gene markers to rice germplasm accessions. A molecular survey was conducted to identify the presence of major blast resistance (R) gene in 363 accessions of Korea landrace rice germplasm. The results revealed that the resistance gene Pik-p (100%), Pib (98%), Pi-d(t)2 (98%) and Piz (76%) were widely observed in tested rice germplasm, but Pita-2, Pik and Pi39 gene were identified in less than 10 accessions. Most of landrace contain the four or five different resistant genes, but these results was not consist of field nursery screening. 13 accessions were shown the blast resistance in field nursery screening and Pik-p, Pib, Pi-d(t)2 and Piz genes were observed in these accessions. The evaluation results of blast resistance genes in rice germplasm will help in breeding of multi disease resistant varieties.