• Journal of Life Science
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• v.27 no.12
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• pp.1415-1420
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• 2017

The metallothionein (MT) gene (IbMT3) was selected from an EST library of suspension-cultured sweet potato cells. The MT gene, which is one of abundant ESTs in the library, is involved in stress regulation of cells and tissues. A full-length IbMT3 cDNA was obtained and analysis of its nucleotide sequence revealed that IbMT3 encoded a type 3 MT protein, based on its structural characteristics. The function of type 3 MT in plants is not yet known. Northern blot analysis showed stronger expression of IbMT3 in suspension-cultured cells than in sweet potato plant leaves. Since cell culture is known to impose a state of oxidative stress on cells, sweet potato plants were subjected to oxidative stress to investigate the transcriptional regulation of IbMT3. When the herbicide methyl viologen (MV) was administered for 6, 12, and 24 hr, IbMT3 transcription rapidly increased at 6 hr and then decreased. A cold treatment at $15^{\circ}C$ for 24 and 48 hr resulted in a gradual increase in IbMT3 expression. These findings indicate that IbMT3 expression is regulated in response to environmental and oxidative stress. IbMT3 isoform is expected to have antioxidant effects in sweet potato plants and may play an important role in cellular adaptation to oxidative stress.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.126-131
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• 2005

Richadella dulcifica, a native shrub in tropical West Africa, gives red berries that have the unusual property of modifying a sour taste into a sweet taste. The red berries contain a taste-modifying protein named miraculin. A synthetic gene encoding miraculin was placed under the control of constitutive promoters and transferred to lettuce. High expression of miraculin was obtained, with accumulation of up to 1% total soluble protein in lettuce leaf. In addition, the miraculin expressed in lettuce possesses a taste-modifying activity.

• The Korean Journal of Mycology
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• v.42 no.1
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• pp.91-94
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• 2014

In June 2013, surface rot symptoms were observed on sweet potatoes (Ipomoea batatas) in Yeoju city, Korea. The lesions were circular, light to dark brown, firm, dry, and superficial. The diseased area became sunken in older tissues, and the symptoms usually did not extend deeply into the flesh. Seven isolates of Fusarium species were isolated from diseased sweet potatoes. All isolates were identified as Fusarium oxysporum based on morphological characteristics on CLA medium. To confirm the identification, molecular analysis of elongation factor 1 alpha gene was conducted. Among the isolates, however, four isolates were F. commune, and three isolates were F. oxysporum based on the DNA sequence data. Pathogenicity was tested using agar block inoculation on wounded or unwounded sweet potato pieces. Lesions were observed on wounded sweet potato pieces after 7 days inoculation in only F. commune isolates. This is the first report that F. commune causes Fusarium surface rot of sweet potato in Korea.

• Journal of Plant Biotechnology
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• v.45 no.3
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• pp.257-265
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• 2018

Sweetener is one of the additives that makes you feel sweet. Artificial sweeteners and sugar are typical examples, and sweetness proteins with sweetness characteristics have been widely studied. These studies elucidated the transformation lettuce cells with Agrobacterium method for stable production of natural sweet proteins, brazzein, thaumatin, and miraculin. In this paper, we report use of a plant expression system for production of sweet proteins. A synthetic gene encoding sweet proteins was placed under the control of constitutive promoters and transferred to lettuce. High and genetically stable expression of sweetener was confirmed in leaves by RT-PCR and Western blot analysis. Sweet proteins expressed in transgenic lettuce had sweetness-inducing activity. Results demonstrate recombinant sweet proteins correctly processed in transgenic lettuce plants, and that this production system could be a viable alternative to production from the native plant.

• Proceedings of the IEEK Conference
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• 2004.06a
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• pp.301-304
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• 2004

In this paper, we propose a method to find the optimal direction of the multi beam between each station on the point-to-point link by genetic algorithm. In the proposed method, maximum value in optimal direction on each station is used as a fitness function. The beam of millimeter wave generates a lot of multi-peak because of much influence of noise. About each gene, we simulated this method using 16bit, 32bit, and 32bit split algorithm. 32bit split uses 16bit gene information. Each antenna makes 32bit gene information by adding gene information of two antennas having 16bit gene. Through the proposed method, we could have gotten a good output without 32bit gene information.

• Journal of Life Science
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• v.20 no.3
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• pp.462-465
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• 2010

Sweetness plays an important role in providing calories and promoting appetite for food. Since it has been known that genetic factor(s) is involved in individual differences in taste sensitivity in humans, this study aimed to examine genetic variations of the TAS1R2 gene, one of the components for tasting sweet compounds, by using DNA sequencing analysis from 98 unrelated Korean subjects. As a result, 12 different single nucleotide polymorphisms (SNPs) were identified in the hTAS1R2 gene and most of them were nonsynonymous. Also, two novel SNPs were found for the first time in this study. It was noted that the frequencies of these SNPs were common in the Korean population. 20 different haplotypes with coding SNPs (cSNPs) were also found in this study. Three out of these haplotypes were common, showing frequencies of > 10%. The repertoire and frequencies of cSNPs and haplotypes in the hTAS1R2 gene will provide information that will help identify a functional ligand receptor common in the Korean population.

• Biomedical Science Letters
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• v.26 no.2
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• pp.85-92
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• 2020

Various beneficial effects of sweet persimmon (Diospyros kaki T.) including anti-oxidation, anti-bacteria and viruses, anti-allergy were widely reported previously. However, the anti-inflammatory effect and its molecular mechanisms are not clear. In this study, the anti-inflammatory effect of the extracts of flower bud and fruit of sweet persimmon was investigated in LPS-treated RAW264.7 cells. Both extracts of flower bud and fruit showed strong inhibitory effect on the LPS-induced NF-κB activation. IκBα, the inhibitor of NF-κB, was increased and the expressions of NF-κB target genes, COX-2 and iNOS, were suppressed by the treatment with the extracts of flower bud and fruit. The expressions of pro-inflammatory cytokines, IL-1β, IL-6, TNF-α were also suppressed by the extracts. In addition, the LPS-induced wnt/β-catenin pathway and its related gene expressions including cyclin D1, wnt 3a, wnt 5a were suppressed by the extracts. The extracts also showed anti-oxidant activity and suppressive effect on the LPS-induced apoptosis of RAW264.7 cells. These results suggest that the flower bud and fruit of sweet persimmon display strong anti-inflammatory effect through inhibiting the pro-inflammatory signaling pathways in the cells.

• Journal of Microbiology and Biotechnology
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• v.26 no.3
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• pp.488-492
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• 2016

Rhodococcus species have become increasingly important owing to their ability to degrade a wide range of toxic chemicals and produce bioactive compounds. Here, we report isolation of the Rhodococcus sp. KB6, which is a new leaf-inhabiting endophytic bacterium that suppresses black rot disease in sweet potato leaves. We determined the 7.0 Mb draft genome sequence of KB6 and have predicted 19 biosynthetic gene clusters for secondary metabolites, including heterobactins, which are a new class of siderophores. Notably, we showed the first internal colonization of host plants with Rhodococcus sp. KB6 and discuss its potential as a biocontrol agent for sustainable agriculture.

• Journal of Biomedical and Translational Research
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• v.19 no.4
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• pp.92-102
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• 2018

The objectives of this study were to find out the plant to enhance immune activity among 42 kinds of foods frequently consumed by the Korean elderly consisting of 5 food groups and 5 wild plants. Each sample was assessed the immunoactive effect by measuring $NF-{\kappa}B/AP1$ gene expression, nitric oxide and cytokine production in $RAW-Blue^{TM}$ cell. Soybean sprouts of 47 plants showed the highest $NF-{\kappa}B/AP1$ gene expression at the level of $1.13{\pm}0.03$ (O.D. 650 nm) and Soritae, sweet potato, banana, apple, garlic, crown daisy, cabbage and Ailanthus altissima also had high activity of $NF-{\kappa}B/AP1$ gene in $RAW-Blue^{TM}$ cell stimulated by LPS. NO production of Ailanthus altissima was significantly higher than that of other plants and 16 plants of glutinous sorghum, black rice, Seoritae, Heuktae, sweet potato, banana, apple, garlic, mungbean sprouts, spinach, crown daisy, young pumpkin, cabbage, soybean sprouts, Actinidia arguta and Aster scaber were the next best activity. The above results selected 17 out of 47 plant samples. Moreover, soybean sprouts was significantly shown to increase $TNF-{\alpha}$ ($1,509.55{\pm}1.38pg/mL$) and $IL-1{\beta}$ ($54.56{\pm}1.08pg/mL$) cytokines in comparison with RAW-Blue cell stimulated by LPS. According to the results of in vitro evaluation, the ethanol extract of soybean sprout increased the production of immune-enhancing cytokines by proliferation of macrophages. In addition, $NF-{\kappa}B$ transcription factor activity and NO production ability were excellent, and it was selected as a material having excellent immunological activity.

• Applied Chemistry for Engineering
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• v.24 no.5
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• pp.525-529
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• 2013

Contents of the total polyphenols and flavonoids in the dietary fiber from tubers and stalks of domestic sweet potatoes were investigated. In addition, their antioxidant activity as well as the potent anti-cancer effects through the growth inhibition in human colon cancer cells (HT-29) in vitro were tested. The total flavonoids as naringin equivalents in dietary fiber from tubers and stalks of sweet potatoes were $0.5{\pm}0.001$ naringin/g extract and $2.0{\pm}0.008$ mg naringin/g extract dry basis, respectively. The amounts of the total polyphenols as gallic acid equivalents were $2.8{\pm}0.01$ mg gallic acid/g dry basis and $6.3{\pm}0.03$ mg gallic acid/g dry basis, respectively. 1,2-Diphenyi-1-picrylhydrazyl (DPPH) radical-scavenging activity of the dietary fiber from stalks was 2.4 times higher than that of the dietary fiber from tubers. Interestingly, a strong growth inhibition on HT-29 cells was observed in both dietary fibers originated from stalks and tubers of sweet potato in a dose-dependent manner. In addition, we found that the dietary fiber from tubers and stalks of sweet potato increased the gene expression of tumor suppressor p53. The great potential value in the prevention of various diseases including cancer the potential value could be confirmed through effects of the dietary fiber from tubers and stalks of sweet potato on antioxidant activity and anticancer in human colon cancer.