• Research in Plant Disease
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• v.16 no.2
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• pp.141-147
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• 2010

Resistance to Phytophthora blight (Phytophthora capsici Leonian) of commercial cultivars of Capsicum pepper in Korea were evaluated from 2008 to 2010. In 2008 and 2009, the cultivars were tested for resistance to the Pc003 isolate collected in Youngyang, Gyeongbuk province. In 2010, the selected cultivars in the previous years were tested by inoculating with 3 isolates obtained from the pepper plants in Miryang in Gyeongnam province, Youngyang in Gyeongbuk province, and Goesan in Chungbuk province. A continuous variation in resistance from highly resistant to susceptible was observed among the commercial pepper cultivars. It was also noted that some cultivars, although their names were initiating with 'Yeokgang' or 'PR' meaning Phytophthora resistance, were very low in resistance or susceptible. When the resistant cultivars selected in 2008 and 2009 experiment were inoculated with the 3 isolates, all the commercial cultivars except a rootstock, 'Tantan', succumbed to the exceptionally virulent Pc005 (Miryang) isolate. Pc002 (Goesan) was a little more virulent than Pc003 (Youngyang). A few cultivars resistant to Pc003 (Youngyang) were severely infected by Pc002 (Goesan). Significant interaction in analysis of variance suggested the differential interactions between cultivars and pathogen isolates. Strategies to breed cultivars having high level of resistance to the highly variable pathogenic fungus, Phytophthora capsici, were discussed.

• Archives of Pharmacal Research
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• v.19 no.1
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• pp.46-51
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• 1996

The in vitro activity of LB 10517, a new catechol-substituted cephalosporin, was compared with those of E-1077, cefpirome and ceftazidime 1034 clinical isolates collected in Japan. LB10517 showed a broad-spectrum antibacterial activity against a wide range of grampositive and gram-negative bacteria including non-glucose fermenting rods, Pseudomonas aeruginosa. Against the methicillin-susceptible strains of Staphylococcus aureus (MSSA) and Strptoccus pyogenes, the $MIC_{90}$ values of LB10517 which required to inhibit 90% of the strains wre $3.13\mug/ml\; and\; 0.1\mug/ml$, respectively. It was as active as E-1077 but more active than cefpirome and ceftazidime. Methicillin-resistant strains of S.aureus (MRSA) and Enterococcus spp. were highly resistant to all the test compunds. LB10517 was highly active against most members of the family Enterobacteriaceae, 90% of which were inhibited at a concentration of less than $0.78\mug/ml$, except for Enterobacter cloacae ($1.56\mug/ml$) and Serratia marcescens ($3.13\mug/ml$)Its activity was comparable to those of E-1077 and cefpirome but it was greater than that of ceftazidime. Against Pseudomonas aeruginosa, LB10517 showed the most potent antibacterial activity among the compounds tested. Ninety percent of P. aeruginosa isolates were susceptible at the concentration of $0.39\mug/ml$. Its activity was 32-to 128 fold higher than those of E-1077, cefpirome and ceftazidime. Against imipenem- or ofloxacin-resistant P. aeruginosa, LB10517 with $MIC_{90}\; of\; 6.25 \\mug/ml\; and\; 3.13\mug/ml$, respectively, showed 16-fold more potent activity than the other test compounds. LB10517 showed a relatively high plasma level and long plasma elimination half-life in rats $(t_{1/2}(\beta,\; 52 min)\; and\; dogs\; (t_{1/2}(\beta),\; 103 min)$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.9
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• pp.2396-2401
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• 2009

This study is on development of UV-cured hard coating compounds which have more improved abrasion resistance than existing UV-cured urethane-acrylic resin, to prevent a surface of a widely used PVC tile as a constructive material from being scratched. To make a high abrasion resistant hard coating solution compared to UV-cured urethane-acrylic resin which has no abrasion resistance and been used for PVC tiles, we added powder substances of different abrasion resistant level, $Al_2O_3$(Al-160SG-3), $Al(OH)_3$(SH-8W), $SiO_2$(KS-5000), etc., to the resin, changing their contents from 10% to 30% against quantities of resin, and compounded it using Ring-Mill. After coating PVC tiles with the hard coating solution using bar-coating method that can adjust a thickness, we estimated some surface properties-abrasion resistance, pencil hardness, adhesive power, thickness of coating, and so on. As a result, a hard coating solution added 30% $Al_2O_3$ powder to the resin had the finest surface properties-the first grade in abrasion resistance, H in pencil hardness, 100% in adhesive power, and a hard coating solution which showed excellent solidity and abrasion resistance has smaller particle size, higher powder content, and thicker coating thickness.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.62-62
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• 2019

Bacterial leaf blight(BLB), caused by X. oryzae pv. oryzae(Xoo), is one of the most destructive diseases of rice due to its high epidemic potential. Understanding BLB resistance at a genetic level is important to further improve the rice breeding that provides one of the best approaches to control BLB disease. In the present investigation, a collection of 192 accessions was used in the genome-wide association study (GWAS) for BLB resistance loci against four Korean races of Xoo that were represented by the prevailing BLB isolates under Xoo differential system. A total of 192 accessions of rice germplasm were selected on the basis of the bioassay using four isolated races of Xoo such as K1 and K2. The selected accessions was used to prepare 384-plex genotyping by sequencing (GBS) libraries and Illumina HiSeq 2000 pairedend read was used for GBS sequencing. GWAS was conducted using TASSEL 5.0. The TASSEL program uses a mixed linear model (MLM). The results of the bioassay using a selected set of 192 accessions showed that a large number of accessions (93.75%) were resistant to K1 race and K2 resistant germplasm proportion remained between 66.67. The genotypic data produced SNP matrix for a total of 293,379 SNPs. After imputation the missing data was removed, which exhibited 34,724 SNPs for association analysis. GWAS results showed strong signals of association at a threshold of [-log10(P-value)] more than 5 (K1 and K2) for nine of the 39 SNPs, which are plausible candidate loci of resistance genes. These SNP loci were positioned on rice chromosome 2, 9, and 11 for K1 and K2 races. The significant loci detected have also been illustrated and make the CPAS markers for NBS-LRR type disease resistance protein, SNARE domain containing protein, Histone deacetylase 19, NADP-dependent oxidoreductase, and other expressed and unknown proteins. Our results provide a better understanding of the distribution of genetic variation of BLB resistance to Korean pathogen races and breeding of resistant rice.

• Animal Bioscience
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• v.35 no.11
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• pp.1698-1710
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• 2022

Objective: Raw potato starch (RPS) is resistant to digestion, escapes absorption, and is metabolized by intestinal microflora in the large intestine and acts as their energy source. In this study, we compared the effect of different concentrations of RPS on the intestinal bacterial community of weaned piglets. Methods: Male weaned piglets (25-days-old, 7.03±0.49 kg) were either fed a corn/soybean-based control diet (CON, n = 6) or two treatment diets supplemented with 5% RPS (RPS5, n = 4) or 10% RPS (RPS10, n = 4) for 20 days and their fecal samples were collected. The day 0 and 20 samples were analyzed using a 16S rRNA gene sequencing technology, followed by total genomic DNA extraction, library construction, and high-throughput sequencing. After statistical analysis, five phyla and 45 genera accounting for over 0.5% of the reads in any of the three groups were further analyzed. Furthermore, short-chain fatty acids (SCFAs) in the day 20 fecal samples were analyzed using gas chromatography. Results: Significant changes were not observed in the bacterial composition at the phylum level even after 20 d post feeding (dpf); however, the abundance of Intestinimonas and Barnesiella decreased in both RPS treatment groups compared to the CON group. Consumption of 5% RPS increased the abundance of Roseburia (p<0.05) and decreased the abundance of Clostridium (p<0.01) and Mediterraneibacter (p< 0.05). In contrast, consumption of 10% RPS increased the abundance of Olsenella (p<0.05) and decreased the abundance of Campylobacter (p<0.05), Kineothrix (p<0.05), Paraprevotella (p<0.05), and Vallitalea (p<0.05). Additionally, acetate (p<0.01), butyrate (p<0.05), valerate (p = 0.01), and total SCFAs (p = 0.01) were upregulated in the RPS5 treatment group Conclusion: Feeding 5% RPS altered bacterial community composition and promoted gut health in weaned piglets. Thus, resistant starch as a feed additive may prevent diarrhea in piglets during weaning.

• Archives of Pharmacal Research
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• v.29 no.10
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• pp.866-873
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• 2006

When patients with cancers are treated with chemotherapeutic agents a long time, some of the cancer cells develop the multidrug resistance (MDR) phenotype. MDR cancer cells are characterized by the overexpression of multidrug resistance1 (MDR1) gene which encodes P-glycoprotein (Pgp), a surface protein of tumor cells that functions to produce an excessive efflux and thereby an insufficient intracellular concentration of chemotherapeutic agents. A variety of studies have sought potent MDR modulators to decrease MDR1 gene expression in cancer cells. Our previous study has shown that curcumin exhibits characteristics of a MDR modulator in KB-V1 multidrug-resistant cells. The aim of this study was to further investigate the effect of curcumin on MDR1 gene expression in patient leukemic cells. The leukemic cells were collected from 78 childhood leukemia patients admitted at Maharaj Nakorn Chiang Mai Hospital, Chiang Mai, Thailand, in the period from July 2003 to February 2005. There were 61 cases of acute lymphoblastic leukemia (ALL), 14 cases of acute myeloblastic leukemia (AML), and 3 cases of chronic myelocytic leukemia (CML). There were 47 males and 31 females ranging from 1 to 15 years old. Bone marrows were collected. The leukemic cells were separated and cultured in the presence or absence of $10{\mu}M$ curcumin for 48 hours. MDR1 mRNA levels were determined by RT-PCR. It was found that curcumin reduced MDR1 gene expression in the cells from 33 patients (42%). Curcumin affected the MDR1 gene expression in 5 of 11 relapsed cases (45%), 10 of 26 cases of drug maintenance (38%), 7 of 18 cases of completed treatment (39%), and 11 of 23 cases of new patients (48%). The expression levels of MDR1 gene in leukemic patient cells as compared to that of KB-V1 cells were classified as low level (1-20%) in 5 of 20 cases (25%), medium level (21-60%) in 14 of 32 cases (44%), and high level (61-100%) in 14 of 20 cases (70%). In summary, curcumin decreased MDR1 mRNA level in patient leukemic cells, especially in high level of MDR1 gene groups. Thus, curcumin treatment may provide a lead for clinical treatment of leukemia patients in the future.

• Korean journal of applied entomology
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• v.35 no.3
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• pp.254-259
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• 1996

The biochemical factors responsible for parathion resistance in a ethyl fenitrothion-selected Yumenoshima I11 (EF-30) strain of the housefly were examined. Great difference (167-fold) in the Iso was observed between the resistant EF-30 (R) and susceptible SRS (S) strains in vitro, suggesting that altered acetylcholinesterase (AChE) in the housefly strain was an important factor in the resistance. The in vitro degradative activity of parathion and paraoxon in both strains was associated with the microsomal and soluble fractions and required NADPH and reduced glutahione (GSH), respectively. The R strain possessed higher activity for GSH S-transferase than the S strain, and this enzyme appears to be important in the resistance mechanism. The R strain was highly resistant to parathion (101,487-fold), but substitution of the methoxy group for ethoxy group decreased the resistance level (25,914-fold) and parathion could be a substrate of GSH S-transferase. It is concluded that the combination of some factors (altered AChE, and enhanced activity of cytochrome P450 dependent monooxygenase and GSH S-transferase) could be sufficient to account for the extremely high level of resistance to parathion and parathion-methyl, although a possible involvement of other factor(s) can not be excluded.

• Applied Biological Chemistry
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• v.34 no.2
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• pp.168-173
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• 1991

The uptake of $Mn^{+2}$, a metal cofactor Mn-SOD, by rice seedings resulted in not only a substantial increase in SOD activity in leaf tissues of the plants, but also a significant enhancement of their cold tolerance : the relative extent of the cold tolerance appeared to accord with relative level of the SOD activity. In contrast, $Fe^{+3},\;Cu^{+2}$ and $Zn^{+2}$, which are the cofactors of Fe-SOD and Cu/Zn-SOD, were found to be ineffective for increasing the SOD activity as well as for improving the chilling-resistant capacity of the plants. The results suggest that Mn-SOD, which is most likely induced by its substrate(superoxide) and activated by the presence of $Mn^{+2}$a at high level, is the enzyme acting as an active component of the defense system against low temperature stress in rice plants. In addition, the application of abscisic acid which has been know to protect to some extent certain plants from chilling injury brought about an increase in SOD activity in rice tissues, providing another affirmative information for the crucial role of SOD under the circumstance of cold stress in plants.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.3
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• pp.511-517
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• 1992

Ethanol was utilized by mixed rumen microbes, but addition of pentachlorophenol (25 mg/l), a methanogen inhibitor, suppressed the utilization of ethanol. Carbon monoxide (50% of the gas phase), a hydrogenase inhibitor, more strongly suppressed the utilization of ethanol, propanol, and butanol. These results suggest that the major ethanol utilizers are $H_2$ producers. Ethanol utilization was depressed at low pH (below 6.0). Since methanogens were shown to be relatively resistant to low pH, it appears that ethanol utilizers are particularly sensitive to low pH. Ruminococcus albus and R. flavefaciens in mono-culture produced ethanol from carbohydrate (glucose and cellobiose), even when a high level (170 mM) of ethanol was present. Ethanol was not utilized even in the absence of carbohydrate, but the co-culture of these bacteria with methanogens resulted in the utilization of ethanol, i.e., when $H_2$ was rapidly converted to $CH_4$, R. albus and R. flavefaciens utilized ethanol. These results suggest that ethanol is utilized when the electrons liberated by the oxidation of ethanol are rapidly removed, and ready electron disposal in ethanol-utilizing, $H_2$-producing bacteria is accomplished by the interspecies transfer of $H_2$.

• Journal of Food Hygiene and Safety
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• v.9 no.3
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• pp.141-149
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• 1994

To investigate the distribution of Vibrio parahaemopyticus in the southern 4 coastal areas, Vibrio parahaemolyticus was isolated from seawater, shellfish and sediment from May to October in 1991, and antimicrobial effect of grapefruit seed extract (GFSE) on the growth of isolated strains were examined. In the 120 sample from 4 coastal areas, 16 strains of Vibrio parahaemolyticus were isolated and identified. The distribution serotype of isolated strains was 10 types of monovalent k-antiserum. Especially k-5 and k-28 were highly distribyted with 3 and 4 strains. 31.3% of isolated strains showed positive on Kanagawa phenomenon test. All isolated Vibrio parahaemolyticus were sensitive to chloramphenicol and gentamycin, 5 and 6 strains were resistant to streptomycin and colistin, respectively. Isolated strains were compared with geographical, month and sample. The distribution of 16 isolated Vibrio parahamolyticus was high at Hadong with 50%(8 strains), on July with 43.8%(7 strains) and from seawater with 37.5%(6 strains) respectively. Minimal inhibitory level of GFSE to Vibrio parahaemolyticus was 50 ppm. With 100 ppm treatment of GFSE, the destroy of cell membrane function, outflow of cell ingredients and ghost morphology of cell were investigated.