• Korean Journal of Plant Resources
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• v.27 no.4
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• pp.271-278
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• 2014

Rubus coreanus has been used as a traditional medicine in Asia because of its various pharmacological properties. This study examined the effects of protocatechuic acid (PCA), one of phenolic compounds derived from R. coreanus on the lipid metabolism in high cholesterol diet-induced mice. A total of 30 male C57BL/6 mice were divided into 5 groups with 6 mice in each group as follows: (1) Control mice received normal diet (ND). (2) Mice received high-cholesterol diet (HCD) plus water, 10% sucrose solution and treated daily oral phosphate-buffered-saline (PBS) of equal volumes through gavage. (3) Mice received HCD and treated daily with 25 mg/kg b.w./day of PCA (4) with 50 mg/kg b.w./day or (5) with 10 mg/kg b.w./day of simvastatin via oral gavage for 12 weeks. Body weights were measured weekly for a period of experiment. After treatment, liver, thymus, spleen and kidney were harvested and weighed, and the lipid metabolite profiles (total cholesterol, triglyceride (TG), HDL-cholesterol (HDL-c), LDL-cholesterol (LDL-c) and liver-damaging markers (GOT and GPT) in serum were examined. PCA significantly reduced the total cholesterol, TG, LDL-c level and increased the HDL-c level. PCA administration also significantly reduced the levels of GOT and GPT. These results indicate that the PCA could be used as a functional material for lowering lipid and an adjuvant for the treatment of hyperlipemia.

• Korean Journal of Environmental Agriculture
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• v.34 no.2
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• pp.111-119
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• 2015

BACKGROUND: Ethychlozate (ECZ) is a plant growth regulator of synthetic auxin for agricultural commodities (ACs). Accurate and sensitive method to determine ECZ in diverse ACs on global official purpose is required to legal residue regulation. As the current official method is confined to the limited type of crops with poor validation, this study was conducted to improve and extend the ECZ method using high-performance liquid chromatography (HPLC) in all the registered crops with method verification. METHODS AND RESULTS: ECZ and its acidic metabolite (ECZA) were both extracted from acidified samples with acetone and briefly purified by dichloromethane partition. ECZ was hydrolyzed to form ECZA and the combined ECZA was finally purified by ion-associated partition including hexane-washing. The instrumental quantitation was performed using HPLC/ FLD under ion-suppression of ECZA with no interference by sample co-extractives. The average recoveries of intra- and inter-day experiment ranged from 82.0 to 105.2% and 81.7 to 102.8%, respectively. The repeatability and reproducibility for intra- and inter-day measurements expressed as a relative standard deviation was less than 8.7% and 7.4%, respectively. CONCLUSION: Established analytical method for ECZ residue in ACs was applicable to the nation-wide pesticide residues monitoring program with the acceptable level of sensitivity, repeatability and reproducibility.

• Journal of Microbiology and Biotechnology
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• v.30 no.3
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• pp.417-426
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• 2020

Bacillus amyloliquefaciens is an important plant disease-preventing and growth-promoting microorganism. B. amyloliquefaciens WS-8 can stimulate plant growth and has strong antifungal properties. In this study, we sequenced the complete genome of B. amyloliquefaciens WS-8 by Pacific Biosciences RSII (PacBio) Single Molecule Real-Time (SMRT) sequencing. The genome consists of one chromosome (3,929,787 bp) and no additional plasmids. The main bacteriostatic substances were determined by genome, transcriptome, and mass spectrometry data. We thereby laid a theoretical foundation for the utilization of the strain. By genomic analysis, we identified 19 putative biosynthetic gene clusters for secondary metabolites, most of which are potentially involved in the biosynthesis of numerous bioactive metabolites, including difficidin, fengycin, and surfactin. Furthermore, a potential class II lanthipeptide biosynthetic gene cluster and genes that are involved in auxin biosynthesis were found. Through the analysis of transcriptome data, we found that the key bacteriostatic genes, as predicted in the genome, exhibited different levels of mRNA expression. Through metabolite isolation, purification, and exposure experiments, we found that a variety of metabolites of WS-8 exert an inhibitory effect on the necrotrophic fungus Botrytis cinerea, which causes gray mold; by mass spectrometry, we found that the main substances are mainly iturins and fengycins. Therefore, this strain has the potential to be utilized as an antifungal agent in agriculture.

• Journal of Microbiology and Biotechnology
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• v.17 no.3
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• pp.414-419
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• 2007

Botryococcus braunii is a green colonial fresh water microalga and it is recognized as one of the renewable resources for production of liquid hydrocarbons. CFTRI-Bb-l and CFTRI-Bb-2 have been reported for the first time and their performance with regard to growth and biochemical profile is presented here. The present study focused on effect of carbon dioxide $(CO_2)$ on biomass, hydrocarbon, carbohydrate production, fatty acid profile, and carotenoid content in various species of B. braunii (LB-572, SAG 30.81, MCRC-Bb, N-836, CFTRI-Bb-l, and CFTRI-Bb-2) at 0.5, 1.0, and 2.0% (v/v) levels using a two-tier flask. $CO_2$ at 2.0% (v/v) level enhanced growth of the organism, and a two-fold increase in biomass and carotenoid contents was observed in all the B. braunii strains studied compared with control culture (without $CO_2$ supplementation). At 1 % and 2% (v/v) $CO_2$ concentrations, palmitic acid and oleic acid levels increased by 2.5 to 3 folds in one of the strains of B. braunii (LB-572). Hydrocarbon content was found to be above 20% at 2% $CO_2$ level in the B. braunii LB-572, CFTRI-Bb-2, CFTRI-Bb-l, and N-836 strains, whereas it was less than 20% in the SAG 30.81 and MCRC-Bb strains compared with control culture. This culture methodology will provide information on $CO_2$ requirement for growth of algae and metabolite production. B. braunii spp. can be grown at the tested levels of $CO_2$ concentration without much influence on culture pH.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.4
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• pp.401-408
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• 2016

The present study described the isolation of 2-methylbutyric acid (2-MBA) produced from Bacillus pumilus L1, to subsequently investigate its nematicidal activity for the control of the root-knot nematode. The results showed that 2-MBA could be purified by chromatographic techniques and was identified using nuclear magnetic resonance and liquid chromatography-mass spectrometry. Crude extract and partially purified compounds had a significant effect on the inhibition of egg hatchability and second-stage juvenile (J2) mortality. A dose-dependent effect of 2-MBA was observed for J2 mortality and egg hatchability. Egg hatchability was 69.2%, 59.9%, 32.7%, and 0.0% at 125, 250, 500, and $1000{\mu}g\;mL^{-1}$ of 2-MBA after 4 d of incubation, respectively. Meanwhile, J2 mortality was in the range of 24.4%-100.0% after 2 d of incubation, depending on the concentrations of 2-MBA used. A pot experiment also demonstrated that treatment of B. pumilus L1 culture caused a significant reduction in the number of galls, egg masses, and J2 population than that of the tap water (TW) control. However, as the B. pumilus L1 culture concentration was decreased, the efficacy of nematode control by treatment of B. pumilus L1 culture was reduced compared to that of TW. B. pumilus L1 inoculation at different concentrations also promoted cucumber plant growth. Therefore, our study demonstrated the potential of 2-MBA from B. pumilus L1 as a biocontrol agent against the root-knot nematode and a plant growth promoter for cucumber plants.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2012.05a
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• pp.8-8
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• 2012

Ginseng have been traditionally used for strengthening immunity, providing nutrition and recovering health from fatigue. Recently, pharmaceutical activities of ginseng roots have been proven by many researches, and ginseng has become a world-famous medicinal plant. Ginseng saponin, ginsenoside, is one of the most important secondary metabolite in ginseng which has various pharmacological activities. Many studies have aimed to convert major ginsenosides to the more active minor ginsenoside Rg3 for consumer demand ginseng product. Microbial strain GS514 strain was isolated from soil around ginseng roots for enzymatic preparation of ginsenoside Rg3, which strain shows strong ability of converting ginsenoside Rb1and Rd into Rg3 in the solution with NaCl. The gene encoding a ${\beta}$-glucosidase from this GS514 was cloned and expressed in the BL21 (DE3) strain of Escherichia coli. The recombinant enzyme was purified and characterized. The molecular mass of purified was 87.5 kDa, as determined by SDS-PAGE. The gene sequence revealed significant homology to the family 3 glycoside hydrolases. The purified single enzyme also catalyzed the conversion of ginsenoside Rb1 into Rg3. This target enzyme will be able to produce as much saponin for consumer demand ginseng product. Anti-apoptotic proteins bind with pro-apoptotic proteins to induce apoptosis mechanism. Over expression of these anti-apoptotic proteins lead to several cancers by preventing apoptosis. Docking simulations were performed for anti-apoptotic proteins with several ginsenosides from Panax ginseng. Our finding shows ginsenosides particularly Rg3, Rh2 and Rf have more binding affinity with apoptotic proteins. Further, these docking system of each ginsenosides can be extended to experimental screen system for further brief confirmations of several diseases.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.200-200
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• 2017

Salinity stress is one of the most important abiotic stresses and severely impairs plant growth and production. Root is the first site for nutrient accumulation like as $Na^+$ in the plant. To investigate the response of wheat root under salinity stress, we executed the characterization of morphology and analysis of metabolites. Wheat seeds cv. Keumgang (Korean cultivar) were grown on the moist filter paper in Petri dish. After 5 days, seedlings were transferred to hydroponic apparatus at 1500 LUX light intensity, at $20^{\circ}C$ with 70% relative humidity in a growth chamber. Seedlings (5-day-old) were exposed to 50mM, 75mM, 100mM NaCl for 5 days. Ten-day-old seedlings were used for morphological characterization and metabolite analysis. Root and leaf length became shorter in high NaCl concentration compared to following NaCl treatment. For confirmation of salt accumulation, wheat roots were stained with $CoroNa^+$ Green AM, and fluoresce, and the image was taken by confocal microscopy. $Na^+$ ion accumulation rate was higher at 100mM compared to the untreated sample. Furthermore, to analyze metabolites in the wheat root, samples were extracted by $D_2O$ solvent, and extracted sample was analyzed by 1H NMR spectroscopy. Fourteen metabolites were identified in wheat roots using NMR spectroscopy. Methanol and ethanol were up-regulated, whereas formate, aspartate, aminobutyrate, acetate and valine were down-regulated under salinity stress on roots of wheat. Fumarate had no change, while glucose, betaine, choline, glutamate and lactate were unevenly affected during salinity stress.

• KSBB Journal
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• v.31 no.3
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• pp.158-164
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• 2016

Plant growth promoting (PGP) hormones, which are produced in a small quantity by bacteria, affect in plant growth and development. PGPs play an important role on the crop productivity in agricultural field. In this study, a photosynthetic bacterial strain producing the PGP was isolated from paddy soil. Bacterial isolate was gram negative, rod-shaped and motility positive. From the 16s rRNA gene sequence analysis, the isolate was identified as Rhodobacter capsulatus PS-2. The mass cultivation of R. capsulatus PS-2 was optimized by considering of the carbon, nitrogen and inorganic salt sources. Optimal medium composition was determined as Na-succinate 4.5 g, yeast extract 5 g, $K_2HPO_4$ 1 g, $MgSO_4$ 5 g, per liter. From the result of 500 L fermentation for 2 days using the optimal medium, the viable cells were $8.7{\times}10^9cfu/mL$. R. capsulatus PS-2 strain produced the carotenoid and indole-3-acetic acid (IAA). The carotenoid extraction and quantitative analysis were performed by HCl-assisting method. Total carotenoid contents from R. capsulatus PS-2 culture broth were measured as $7.02{\pm}0.04$ and $6.93{\pm}0.05mg/L$ under photoheterotrophic and chemoheterotrophic conditions, respectively. To measure the productivity of IAA, colorimetric method was employed using Salkowski reagent at optical density 535 nm. The results showed that the highest content of IAA was $197.44{\pm}5.92mg/L$ in the optimal medium supplemented with 0.3% tryptophan.

• Molecules and Cells
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• v.28 no.4
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• pp.331-339
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• 2009

Capsaicin is a very important secondary metabolite that is unique to Capsicum. Capsaicin biosynthesis is regulated developmentally and environmentally in the placenta of hot pepper. To investigate regulation of capsaicin biosynthesis, the promoter (1,537 bp) of pepper capsaicin synthase (CS) was fused to GUS and introduced into Arabidopsis thaliana (Col-0) via Agrobacterium tumefaciens to produce CSPRO::GUS transgenic plants. The CS was specifically expressed in the placenta tissue of immature green fruit. However, the transgenic Arabidopsis showed ectopic GUS expressions in the leaves, flowers and roots, but not in the stems. The CSPRO activity was relatively high under light conditions and was induced by both heat shock and wounding, as CS transcripts were increased by wounding. Exogenous capsaicin caused strong suppression of the CSPRO activity in transgenic Arabidopsis, as demonstrated by suppression of CS expression in the placenta after capsaicin treatment. Furthermore, the differential expression levels of Kas, Pal and pAmt, which are associated with the capsaicinoid biosynthetic pathway, were also suppressed in the placenta by capsaicin treatment. These results support that capsaicin, a feedback inhibitor, plays a pivotal role in regulating gene expression which is involved in the biosynthesis of capsaicinoids.

• Research in Plant Disease
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• v.18 no.1
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• pp.17-23
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• 2012

Indole compound is a bacterial metabolite synthesized and released by an entomopathogenic bacterium, Xenorhabdus nematophila K1. The antibiotic activity was evaluated against plant pathogens, such as Phytophthora blight and anthracnose of red pepper. Indole significantly suppressed mycelial growth of Phytophthora blight and anthracnose pathogens. Under natural sunlight conditions, indole maintained the antifungal activity for at least sixty days. The activity was not affected under the condition of soil-water. When the indole suspension was applied to surface soil before transplanting of red pepper seedlings and was then regularly sprayed to the foliage of the plants with ten days interval, it resulted in significant reduction of the disease occurrences (Phytophthora blight, anthracnose, soft rot, and black mold) by about 30%. These results suggest that indole can be used to control Phytophthora blight and anthracnose of red pepper.