• Korean Journal of Environmental Agriculture
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• v.34 no.2
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• pp.128-133
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• 2015

BACKGROUND: Plant extracts have been used as environment friendly agricultural materials for organic farming in South Korea. However safety evaluation on the plant extracts was not properly tested. The aim of this study was to evaluate safety of the extracts from Melia azedarach, Nerium indicum and Coptis chinensis on cultivating rice. METHODS AND RESULTS: Pant extarcts 300-fold diluted were treated on rice, and residues of M. azedarach, N. indicum and C. chinensis were determined. The analytes from the rice samples were detected by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The method was validated, and good linearities ($r^2=0.995-0.998$), specificity, and recoveries were obtained. Limits of detection were 0.01 mg/kg for all of the target compounds. Recoveries were 79.3-118.3% at 0.1 mg/kg and 75.2-111.5% at 0.5 mg/kg. The residue levels were below 0.030 mg/kg for azadirachtin, 0.320 mg/kg for oleandrin and 1.460 mg/kg for berberine. CONCLUSION(S): The extracts of M. azedarach, N. indicum and C. chinensis contained azadirachtin, oleandrin and berberine as an active ingredient, respectively. The residue of three active ingredients dramatically decreased after treatment in all fruits, stems and roots of rice.

• Journal of Ocean Engineering and Technology
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• v.12 no.3 s.29
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• pp.19-30
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• 1998

In this paper, the dynamic analysis of a dolphin system for mooring a floating structure such as barge mounted plant is studied. The characteristics of the soil-pile system are simplified by a set of equivalent spring elements at the mudline. To evaluate the equivalent spring constants, the finite difference method is used. Since the characteristics of the soil-pile system are nonlinear in case of soft foundation, the nonlinear dynamic analysis technique is needed. The Newmark $beta$ method incorporating the modified Newton-Raphson method(initial stiffness method) is used. A numerical analysis is performed on two mooring dolphin systems on soft foundation and rock foundation. In case of the rock foundation, the characteristics are found to be nearly linear, so the linear dynamic analysis may be sufficient to consider the foundation effect. But in case of soft foundation, the non-linearity of the foundation appears to be very signigicant, so the nonlinear dynamic analysis si needed.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.153-153
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• 2017

Potato (Solanum tubersosum L.) is susceptible to various environmental stresses such as frost, high temperature, and drought. Enhancement of potato drought tolerance can reduce yield loss under drought that has negative effect on potato tuber growth. Genetic engineering can be utilized to achieve this goal, but such approaches using endogenous potato genes have rarely been applied. Since unpredictable global weather changes cause more severe and frequent water limiting conditions, improvement of potato drought tolerance can minimize such adverse effects under drought and can impact on sustainable potato production. Genetic engineering can be utilized to improve potato drought tolerance, but such approaches using endogenous potato genes have rarely been applied. We were obtained AtbZIP28 gene transgenic potato plants. It is identified transcript levels at various stress conditions, polyethylene glycol (PEG), NaCl, abscisic ${\underline{acid}}$ (ABA). Also, For identification to regulate ER stress response genes in AtbZIP28 gene transgenic potato plant, we screened seven potato genes from RNA-seq analysis under TM treatment. Five and two genes were up- and down-regulated by TM, respectively. Their expression patterns were re-examined at stress agents known to elicit TM, DTT, DMSO and salt stress.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.11a
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• pp.71-76
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• 2000

In generally, grouting consists of injecting a suspension or solution into the voids of soils. The low slump mortar grout has been used in America since 1950's. The Compaction Grouting, the injection of a very stiff under relatively high pressure, form a cylinderical grout support pile. The grout generally does not enter soil pores but remains in homogeneous mass that gives controlled displacement either to compact loose soils, or for lifting of structures, or both. In this paper, on the case of the reinforcement construction of 00 plant that the foundation's bearing capacity is insufficient and is to reinforce the foundation, a study has been peformed to analyze the effectiveness of the ground improvement. The bearing capacity of the Compaction Pile has been verified by the S.P.T and the settlement of the improved ground has been monitored rising the magnetic extensometer.

• Journal of the Earthquake Engineering Society of Korea
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• v.9 no.4 s.44
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• pp.1-10
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• 2005

The purpose ol this study Is to suggest a proper analysis model that can evaluate seismic stability for local rock foundation of nuclear power plant. Sliding Analysis, Pseudo-static Analysis and Dynamic Analysis methods are used for analysing NPP rock foundation with the conditions like acting directions of input earthquake, boundary conditions, width and depth of analysing model, and modeling methods of weakness fault zones. As the results of study, Pseudo-static Analysis for lateral roller and dynamic analysis for transfer boundary condition showed good results, and analysing ranges of width and depth were 5 times of structure width and over 2 times ol structure depth.

• Korean Journal of Plant Resources
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• v.35 no.5
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• pp.586-593
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• 2022

Soybean (Glycine max (L.) Merr.) is a high-protein oilseed crop, cultivated worldwide. Soybean seeds are abundant in various secondary metabolites with physiologically active. Mature seeds of 25 soybean cultivars with various morphological and physiological characteristics analyzed for secondary metabolites, such as carotenoid, isoflavone, and soyasaponin. These secondary metabolites showed various content by genotype in 25 cultivars. Total carotenoid content ranged from 1.23 to 33.78 mg/g and three cultivars, such as IT177645, PI90763 and IT234975 with black seed coat showed high levels of total carotenoid. Total isoflavones content ranged from 20.28 to 276.35 mg/100g and were detected high levels in Savoy, PI90763 and KLG16001. In addition, total soyasaponins content ranged from 33.12 to 246 mg/100g and were detected high levels in PI90763, PI86490 and IT234975. The PI90763 was showed abundant content in all of the carotenoid, isoflavones and soyasaponins. These results could be valuable information for the development of new soybean cultivars and regulation of secondary metabolites biosynthesis in soybean.

• Korean Journal of Breeding Science
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• v.51 no.4
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• pp.318-325
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• 2019

Salt stress is a significant factor limiting growth and productivity in crops. However, little is known about the response and resistance mechanism to salt stress in maize. The objective of this research was to develop an enhanced salt-tolerant silage maize by mutagenesis with gamma radiation. To generate gamma radiation-induced salt-tolerant silage maize, we irradiated a KS140 inbred line with 100 Gy gamma rays. Salt tolerance was determined by evaluating plant growth, morphological changes, and gene expression under NaCl stress. We screened 10 salt-tolerant maize inbred lines from 2,248 M₂ mutant populations and selected a line showing better growth under salt stress conditions. The selected 140RS516 mutant exhibited improved seed germination and plant growth when compared with the wild-type under salt stress conditions. Enhanced salt tolerance of the 140RS516 mutant was attributed to higher stomatal conductance and proline content. Using whole-genome re-sequencing analysis, a total of 328 single nucleotide polymorphisms and insertions or deletions were identified in the 140RS516 mutant. We found that the expression of the genes involved in salt stress tolerance, ABP9, CIPK21, and CIPK31, was increased by salt stress in the 140RS516 mutant. Our results suggest that the 140RS516 mutant induced by gamma rays could be a good material for developing cultivars with salt tolerance in maize.

• Journal of Microbiology and Biotechnology
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• v.34 no.8
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• pp.1563-1579
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• 2024

More and more diterpenoids have attracted extensive attention due to the diverse chemical structures and excellent biological activities, and have been developed into clinical drugs or consumer products. The vast majority of diterpenoids are derived from plants. With the long-term development of plant medicinal materials, the natural resources of many plant diterpenoids are decreasing, and the biosynthetic mechanism of key active components has increasingly become a research hotspot. Using synthetic biology to engineer microorganisms into "cell factories" to produce the desired compounds is an essential means to solve these problems. In this review, we depict the plant-derived diterpenoids from chemical structure, biological activities, and biosynthetic pathways. We use representative plant diterpenes as examples to expound the research progress on their biosynthesis, and summarize the heterologous production of plant diterpenoids in microorganisms in recent years, hoping to lay the foundation for the development and application of plant diterpenoids in the future.

• Food Industry And Nutrition
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• v.18 no.2
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• pp.12-16
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• 2013

• 한국약용작물학회:학술대회논문집
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• 2011.09a
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• pp.98-99
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• 2011