• Journal of Microbiology and Biotechnology
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• 제16권12호
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• pp.1940-1946
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• 2006

The influence of environmental conditions on the ganoderic acid (GA) content in the fungus Ganoderma lucidum was investigated using a one-factor-at-a-time design and orthogonal design. Among the various medium components examined, sucrose, soybean powder or peptone, ferrous sulfate, and pH 6.0 were the most suitable carbon source (factor A), nitrogen source (factor B), mineral source (factor C), and initial pH (factor D), respectively, for the GA content in the one-factor-at-a-time design. According to the orthogonal design, the order of effect for the four factors on the GA content was A>C>D>B. The best level of factor A was $A_2$ (sucrose) with a value of +0.34 mg/100 mg DW. The optimal treatment combination was $A_2B_1C_3D_1$ with which the GA content reached up to 2.63$\pm$0.011 mg/100 mg DW. The interactions between the mineral ion and the nitrogen source, and the mineral ion and the pH were both highly significant (P<0.01). The highest interaction effect was ($B_2{\times}D_2$) with a value of +0.19 mg/100 mg DW, which was higher than the level effect value for $B_2$ (peptone) and D$_2$ (pH 5.0). Therefore, the results proved that interactions between factors cannot be ignored. The results also indicated the importance of the interactions between the factors, which may help to understand the metabolic pathway leading to triterpene biosynthesis and the expression and regulation of the key enzymes involved.

• 한국잡초학회지
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• 제12권1호
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• pp.39-45
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• 1992

최근(最近)에 개발(開發)된 수도(水稻) 도복경감제(倒伏輕減劑)를 공시(供試)하여 gibbeellin 길항작용(拮抗作用), auxin 상호작용(相互作用), ethylene 발생(發生) 및 후작물(後作物) 생육(生育)에 마치는 효과(效果)를 검토(檢討)한 바 그 주요결과(主要結果)는 다음과 같다. 1. 수도(水稻) 도복경감제(倒伏輕減劑) (inabenfide, paclobutrazol 및 uniconazole) 처리(處理)가 녹두의 상배축(上胚軸)을 크게 억제(抑制)시켰으나 $GA_3$와의 혼용처리시(混用處理時) $GA_3$ 농도(濃度)가 높을수록 더욱 신장(伸長)되는 길항작용(拮抗作用)을 보였다. 2. 수도(水稻) 도복경감제(倒伏輕減劑) 처리시(處理時) 녹두의 부정근(不定根) 발생(發生)을 현저(顯著)히 증가(增加)시켜 auxin과의 갚은 상호작용(相互作用)이 있는 것으로 추찰(推察)되며, $GA_3$ 농도(濃度)가 높을수록 부정근(不定根)의 발생(發生)이 억제(抑制)되었다. 3. Ethylene 발생(發生)은 수도(水稻) 도복경감제(倒伏輕減劑) 처리(處理)에 依(의)해 단기간(短期間) (5 DAT)에는 증가(增加)하였으나 시간(時間)이 경과(時間)할수록 (10, 30 DAT), 엽량(葉量)이 많을수록 억제(抑制)되었다. 4 후작물(後作物)에 미치는 수도(水稻) 도복경작제(倒伏耕作劑)의 처리효과(處理效果)는 화본과(禾本科)인 보리에서는 별(別)로 큰 영향(影響)이 없었으나 광엽(廣葉)인 토마토에서는 초장(草長)이 크게 억제(抑制)되었다. Inabenfide는 처리후(處理後) 30 일(日)에 회복(回復)이 되었으나 paclobutrazol과 uniconazole은 그 억제(抑制)가 매우 컸다.

• Journal of Microbiology and Biotechnology
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• 제26권1호
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• pp.56-60
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• 2016

Two new glucosides (1 and 2) of geldanamycin (GA) analogs were obtained from in vitro glycosylation by UDP-glycosyltransferase (YjiC). Based on spectroscopic (HR-ESI-MS, 1D, and 2D-NMR) analyses, the glucosides were elucidated as 4,5-dihydro-7-O-descarbamoyl-7-hydroxyl GA-7-O-β-D-glucoside (1) and ACDL3172-18-O-β-D-glucoside (2). Furthermore, the water solubility of compounds 1 and 2 was about 215.2 and 90.7 times higher respectively, than that of the substrates. Among compounds 1-4, only 3 showed weak antiproliferative activity against four human tumor cell lines: MDA-MB-231, SMMC7721, HepG2, and SW480 (IC₅₀: 13.6, 15.1, 31.8, and 22.7 μM, respectively).

• 한국식물학회:학술대회논문집
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• 한국식물학회 1985년도 워크샵 및 심포지엄 북한산국립공원의 식생
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• pp.35-48
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• 1985

Plastids, which are organelles unique to plant cells, bear their own genome that is organized into DNA-protein complexes (nucleoids). Regulation of gene expression in the plastid has been extensively investigated because this organelle plays an important role in photosynthesis. Few attempts, however, have been made to characterize the regulation of plastid gene expression at the chromosomal structure, using plastid nucleoids. In this report, we summarize the recent progress in the characterization of DNA-binding proteins in plastids, with special emphasis on CND41, a DNA binding protein, which we recently identified in the choloroplast nucleoids from photomixotrophically cultured tobacco cells. CND41 is a protein of 502 amino acids which consisted of a transit peptide of 120 amino acids and a mature protein of 382 amino acids. The N-terminal of the 'mature' protein has lysine-rich region which is essential for DNA-binding. CNA41 also showed significant identities to some aspartyl proteases. Protease activity of purified CND41 has been recently confirmed and characterized. On the other hand, characterization of accumulation of CND41 both in wild type and transgenic tobacco with reduced amount of CND41 suggests that CND41 is a negative regulator in chloroplast gene expression. Further investigation indicated that gene expression of CND41 is cell-specifically and developmentally regulated as well as sugar-induced expression. The reduction of CND41 expression in transgenic tobacco also brought the stunted plant growth due to the reduced cell length in stem. GA3 treatment on apical meristem reversed the dwarf phenotype in the transformants. Effects of CND41 expression on GA biosynthesis will be discussed

• Journal of Microbiology and Biotechnology
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• 제19권6호
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• pp.582-587
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• 2009

Immobilized cells of Arthrohacter nitroguajacolicus ZJUTB06-99 capable of producing nitrilase were used for biotransformation of acrylonitrile to acrylic acid. Six different entrapment matrixes were chosen to search for a suitable support in terms of nitrilase activity. Ca-alginate proved to be more advantageous over other counterparts in improvement of the biocatalyst activity and bead mechanical strength. The effects of sodium alginate concentration, $CaCl_2$ concentration, bead diameter, and ratio by weight of cells to alginate, on biosynthesis of acrylic acid by immobilized cells were investigated. Maximum activity was obtained under the conditions of 1.5% sodium alginate concentration, 3.0% $CaCl_2$ concentration, and 2-mm bead size. The beads coated with 0.10% polyethylenimine (PEI) and 0.75% glutaraldehyde (GA) could tolerate more phosphate and decrease leakage amounts of cells from the gel. The beads treated with PEI/GA could be reused up to 20 batches without obvious decrease in activities, which increased about 100% compared with the untreated beads with a longevity of 11 batches.

• 한국작물학회지
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• 제44권2호
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• pp.176-179
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• 1999

Trinexapac-ethyl[ 4-(cyclopropyl- $\alpha$ -hydroxy-methylene)-3,5-dioxocyclohexane carboxylic acid ethylester] is a growth-retardant for plants by inhibiting a key step in biosynthesis of GA. A treatment of trinexapacethyl generally induces a reduction in vegetative growth and also inhibits heading. In addition, the trinexapacethyl was known to enhance the freeze-tolerance in annual bluegrass, however, the mechanism is not known yet. One possible reason for the enhanced freeze-tolerance may be the antifreeze protein known to be accumulated in intercellular space of the leaf during cold acclimation. In order to see the possible in-duction of the synthesis of antifreeze proteins by trinexacpacethyl, the apoplastic proteins extracted from Kentucky bluegrass treated with trinexapacethyl were analyzed by SDS-PAGE and the presence of the antifreeze protein was observed. In addition, western analysis showed the identity of the protein induced by both a cold acclimation and a trinexapacethyl treatment. It appears that an enhanced freeze-tolerance of the turf grass by trinexapacethyl is due to the synthesis and/or accumulation of the antifreeze protein similar to the enhanced freeze tolerance induced by cold acclimation.

• Journal of Microbiology and Biotechnology
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• 제21권9호
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• pp.893-902
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• 2011

Endophytic fungi are little known for their role in gibberellins (GAs) synthesis and abiotic stress resistance in crop plants. We isolated 10 endophytes from the roots of field-grown soybean and screened their culture filtrates (CF) on the GAs biosynthesis mutant rice line - Waito-C. CF bioassay showed that endophyte GMH-1B significantly promoted the growth of Waito-C compared with controls. GMH-1B was identified as Penicillium minioluteum LHL09 on the basis of ITS regions rDNA sequence homology and phylogenetic analyses. GC/MS-SIM analysis of CF of P. minioluteum revealed the presence of bioactive $GA_4$ and $GA_7$. In endophyte-soybean plant interaction, P. minioluteum association significantly promoted growth characteristics (shoot length, shoot fresh and dry biomasses, chlorophyll content, and leaf area) and nitrogen assimilation, with and without sodium chloride (NaCl)-induced salinity (70 and 140 mM) stress, as compared with control. Field-emission scanning electron microcopy showed active colonization of endophyte with host plants before and after stress treatments. In response to salinity stress, low endogenous abscisic acid and high salicylic acid accumulation in endophyte-associated plants elucidated the stress mitigation by P. minioluteum. The endophytic fungal symbiosis of P. minioluteum also increased the daidzein and genistein contents in the soybean as compared with control plants, under salt stress. Thus, P. minioluteum ameliorated the adverse effects of abiotic salinity stress and rescued soybean plant growth by influencing biosynthesis of the plant's hormones and flavonoids.

• 한방안이비인후피부과학회지
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• 제30권4호
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• pp.49-61
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• 2017

Objectives : In order to find out the whitening effects of Leonuri Herba, this study was designed to identify the effects and the action mechanism of LHE(Leonuri Herba extract) on Malignant melanoma cell lines. Methods : After treating LHE on the B16F10 cell-Malignant melanoma cell line-, the cell survival rate, melanin biosynthesis rate, intra&extracellular tyrosinase activity rate, SOD-like activity, tyrosinase mRNA gene expression were investigated. The results were compared with control group without LHE treatment or with positive control group treated with whitening efficacy substance. Results : B16F10 cell survival rate, melanin biosynthesis rate, and intra&extracellular tyrosinase activity were significantly inhibited depending on the concentration of treated LHE. Melanin biosynthesis rate and tyrosinase activity rate were also decreased when ${\alpha}-MSH$ was combined with LHE. In addition, the SOD-like activity was increased in a concentration-dependent manner in the treatment with the LHE, indicating signigicant activity at high concentrations, and the tyrosinase mRNA gene expression was decreased in both the LHE-treated group, the LHE and ${\alpha}-MSH-treated$ group. Conclusions : LHE seems to inhibit melanin synthesis through inhibition of tyrosinase activity and inhibition of tyrosinase mRNA gene expression. It also has the effect of promoting SOD-like activity and may be used clinically as a skin whitening agent in the future.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1999년도 제13회 식물생명공학심포지움 New Approaches to Understand Gene Function in Plants and Application to Plant Biotechnology
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• pp.51-56
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• 1999

Plastids, which are organelles unique to plant cells, bear their own genome that is organized into DNA-protein complexes (nucleoids). Regulation of gene expression in the plastid has been extensively investigated because this organelle plays an important role in photosynthesis. Few attempts, however, have been made to characterize the regulation of plastid gene expression at the chromosomal structure, using plastid nucleoids. In this report, we summarize the recent progress in the characterization of DNA-binding proteins in plastids, with special emphasis on CND41, a DNA binding protein, which we recently identified in the choloroplast nucleoids from photomixotrophically cultured tobacco cells. CND41 is a protein of 502 amino acids which consisted of a transit peptide of 120 amino acids and a mature protein of 382 amino acids. The N-terminal of the 'mature' protein has lysine-rich region which is essential for DNA-binding. CNA41 also showed significant identities to some aspartyl proteases. Protease activity of purified CND41 has been recently confirmed and characterized. On the other hand, characterization of accumulation of CND41 both in wild type and transgenic tobacco with reduced amount of CND41 suggests that CND41 is a negative regulator in chloroplast gene expression. Further investigation indicated that gene expression of CND41 is cell-specifically and developmentally regulated as well as sugar-induced expression. The reduction of CND41 expression in transgenic tobacco also brought the stunted plant growth due to the reduced cell length in stem. GA3 treatment on apical meristem reversed the dwarf phenotype in the transformants. Effects of CND41 expression on GA biosynthesis will be discussed.

• Journal of Microbiology
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• 제43권6호
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• pp.510-515
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• 2005

The growth of red pepper plants was enhanced by treatment with the rhizobacterium, Bacillus cereus MJ-1. Red pepper shoots showed a 1.38-fold increase in fresh weight (fw) and roots showed a 1.28-fold fw gain. This plant growth-promoting rhizobacterium (PGPR) has been reported to produce gibberellins (GAs). Other GAs-producing rhizobacteria, Bacillus macroides CJ-29 and Bacillus pumilus CJ-69, also enhanced the fw of the plants. They were less effective than B. cereus MJ-1, though. The endogenous GAs content of pepper shoots inoculated with MJ-1 was also higher than in shoots inoculated with CJ-29 or CJ-69. When inoculated with MJ-1, bacterial colonization rate of the roots was higher than that of roots inoculated with CJ-29 or CJ-69. These results support the idea that the plant growth-promoting effect of the bacteria also positively related with the efficiency of root colonization by the bacteria. In addition, we identified the major endogenous GAs of the red pepper as originating from both the early C-13 hydroxylation and the early non C-13 hydroxylation pathways, with the latter being the predominant pathway of GA biosynthesis in red pepper shoots.