• Toxicological Research
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• 제21권1호
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• pp.57-62
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• 2005

To investigate the mutant induction of wild ginseng culture extract, we performed chromosomal aberration assay with chinese hamster lung cell in vitro. The test concentration of the extract was decided for the standard with the 50% suppression of cell propagation in the cell. The concentrations for the chromosome test were 1,250, 2,500 and 5,000 ㎍/ml with metabolic activation (+S, 6 hours treatment), 1,100, 2,200 and 4,400 ㎍/ml without metabolic activation (-S, 6 hours treatment) 800, 1,600 and 3,200 ㎍/ml without metabolic activation (-S, 24 hours treatment). No significant increase in chromosome aberrations was observed at any of these concentrations both in the absence and presence of metabolic activation system. Cyclophosphamide monohydrate (CPA) and ethylmethanesulfonate (EMS) caused a significant increase in chromosome aberration. These results may be concluded that wild ginseng culture extract is not capable of inducing chromosome aberration in cultured chinese hamster lung cell regardless of metabolic activation and genotoxicity of that is negative under the present experimental condition.

• Tuberculosis and Respiratory Diseases
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• 제70권6호
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• pp.482-489
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• 2011

Background: Based on the assertion that apocynin diminishes acute lung injury (ALI) by inhibition of NADPH oxidase, the effect of apocynin was tested in interleukin-$1{\alpha}$ (IL-1)-induced ALI in rats. Methods: IL-1 was insufflated into the trachea of Sprague-Dawley rats to induce ALI, and apocynin (8 mg/kg) was given intravenously for inhibition of NADPH oxidase. In addition, we determined whether apocynin inhibited generation of superoxide anions from isolated human neutrophils. Five hours after IL-1 instillation, lung injury parameters, expression of cytosolic phospholipase A2 (cPLA2) by cells from bronchoalveolar lavage (BAL), an index of oxidative stress in lung tissues (${\gamma}$-glutamyltranspeptidase, activity), and ultrastructure of alveolar type II (AT II) cells were evaluated. Results: Apocynin decreased the generation of free radicals from phorbol myristate (PMA)-activated neutrophils in vitro, but did not ameliorate ALI. IL-1 induced enhancement of the expression of cPLA2 on neutrophils was not altered by apocynin. Conclusion: Apocynin induced suppression of the generation of superoxide anions from neutrophils by inhibition of NADPH oxidase does not attenuate IL-1-induced ALI in rats.

• Biomolecules & Therapeutics
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• 제20권5호
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• pp.492-498
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• 2012

Phytochemicals have been known to exhibit potent antioxidant activity. This study examined cytoprotective effects of phytochemicals including quercetin, catechin, caffeic acid, and phytic acid against oxidative damage in SK-Hep-1 cells induced by the oxidative and non-oxidative metabolism of ethanol. Exposure of the cells to excess ethanol resulted in a significant increase in cytotoxicity, reactive oxygen species (ROS) production, lipid hydroperoxide (LPO), and antioxidant enzyme activity. Excess ethanol also caused a reduction in mitochondrial membrane potential (MMP) and the quantity of reduced glutathione (GSH). Co-treatment of cells with ethanol and quercetin, catechin, caffeic acid and phytic acid significantly inhibited oxidative ethanol metabolism-induced cytotoxicity by blocking ROS production. When the cells were treated with ethanol after pretreatment of 4-methylpyrazole (4-MP), increased cytotoxicity, ROS production, antioxidant enzyme activity, and loss of MMP were observed. The addition of quercetin, catechin, caffeic acid and phytic acid to these cells showed suppression of non-oxidative ethanol metabolism-induced cytotoxicity, similar to oxidative ethanol metabolism. These results suggest that quercetin, catechin, caffeic acid and phytic acid have protective effects against ethanol metabolism-induced oxidative insult in SK-Hep-1 cells by blocking ROS production and elevating antioxidant potentials.

• Mycobiology
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• 제31권4호
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• pp.251-254
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• 2003

To select active bacterial strains to control plant diseases, 57 bacterial strains were isolated from the rhizosphere of the plants growing in various areas such as coast, middle and top of Halla Mountain in Jeju Island. Anti-fungal effect of isolated bactrial strains was tested in vitro by incubating in potato dextrose agar with isolates of four fungal plant pathogens Rhizoctonia solani, Fusarium oxysporum, Colletotrichum gloeosporioides and C. orbiculare, respectively. Thirty-four bacterial strains inhibited the hyphal growth of the plant pathogens, from which 17 strains inhibited one of the tested fungi, 10 strains two fungi, six strains three and a strain TRL2-3 inhibited all of the tested fungi. Some bacterial strains could inhibit weakly the hyphal growth of the plant pathogens, whereas some did very strongly with apparent inhibition zone between the plant pathogens and bacterial strains indicating the unfavorable condition for hyphal growth. Although there was no apparent inhibition zone, some bacterial strains showed a strong suppression of hyphal growth of plant pathogens. Especially, the inhibition by TRL2-3 was remarkably strong in all cases of the tested plant pathogens in this study that could be a possible candidate for biological control of various plant diseases.

• 한국자원식물학회지
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• 제35권6호
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• pp.704-712
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• 2022

Research on whitening materials using natural alternatives is actively being conducted. The aim of this study was to investigate the in vitro inhibitory effects of Ranunculus chinensis Bunge (RCB) on melanogenesis and associated enzymes, such as tyrosinase, tyrosinase-related protein (TRP)-1, and TRP-2 in B16F10 murine melanoma cells. We found that RCB extract significantly attenuated melanin synthesis and reduced the activity of intracellular tyrosinase, a rate-limiting melanogenic enzyme. Western blot analysis showed that RCB extract decreased the protein expression of tyrosinase and TRP-1. In addition, it significantly decreased the expression of microphthalmia-associated transcription factor (MITF), a key regulator of melanogenesis. Extracellular signal-regulated kinase (ERK) activation has been reported to be involved in the inhibition of melanogenesis. Thus, we investigated whether the hypopigmentary effects of RCB extract were related to the activation of ERK. RCB extract induced ERK phosphorylation in a dose-dependent manner. Furthermore, it markedly inhibited body pigmentation in a zebrafish model. Our results suggest that RCB extract inhibits melanogenesis by activating ERK pathway-mediated suppression of MITF and its downstream target genes, including tyrosinase. Therefore, RCB extract can be used as a whitening agent in the development of functional cosmetics.

• The Plant Pathology Journal
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• 제39권5호
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• pp.513-521
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• 2023

Seed-borne diseases reduce not only the seed germination and seedling growth but also seed quality, resulting in the significant yield loss in crop production. Plant seed harbors diverse microbes termed endophytes other than pathogens inside it. However, their roles and application to agricultures were rarely understood and explored to date. Recently, we had isolated from soybean seeds culturable endophytes exhibiting in-vitro antagonistic activities against common bacterial and fungal seed-borne pathogens. In this study, we evaluated effects of seed treatment with endophytes on plant growth and protection against the common seed-borne pathogens: four fungal pathogens (Cercospora sojina, C. kikuchii, Septoria glycines, Diaporthe eres) and two bacterial pathogens (Xanthomonas axonopodis pv. glycines, Pseudomonas syringae pv. tabaci). Our experiments showed that treatment of soybean seeds with seed endophytes clearly offer protection against seed-borne pathogens. We also found that some of the endophytes promote plant growth in addition to the disease suppression. Taken together, our results demonstrate agricultural potential of seed endophytes in crop protection.

• Journal of Plant Biotechnology
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• 제1권2호
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• pp.97-100
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• 1999

In order to establish in vitro propagation method of sundew, Drosera rotundifolia L., the effects of MS medium concentration, cytokinin type and concentration, pH, and auxin type and concentration on shoot proliferation and root formation were investigated using shoots at 3 month after seed germination. The highest shoot production was obtained with the half strength of MS ($\frac{1}{2}$ MS) medium than with any other strength of MS medium tested. Addition of kinetin or BA in $\frac{1}{2}$ MS medium was strongly suppressed shoot proliferation. The suppression of shoot proliferation was more effective in BA-supplemented $\frac{1}{2}$ MS medium than kinetin-supplemented. The optimum pH of the media for shoot proliferation was pH 5.7-6.7. Shoots were subcultured in $\frac{1}{2}$ MS medium supplemented with 0.5mg/L 2,4-D for rooting every 8 weeks. All subcultured shoots produced extensive root systems after 5 to 6 week culture. Plantlets after root development were planted in plastic pots filled with moss. The survival rate of plantlets was almost 100%. On subculturing every 8 weeks, hundreds of the plants were propagated from a single plant within a year.

• Molecules and Cells
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• 제19권2호
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• pp.279-282
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• 2005

In mammals, 7-dehydrocholesterol reductase (Dhcr7) is the terminal enzyme in cholesterol biosynthesis. We previously reported that the Dhcr7 proximal promoter (-179 to +1), which contains CpG islands, is responsible for sterol-mediated expression of the rat gene. In the present study, we examined whether methylation of this region affects the transcriptional activity of the Dhcr7 gene. In vitro DNA methylation of the Dhcr7 promoter and luciferase-reporter assays showed that DNA methylation of the CpG islands suppressed transcription. Furthermore, treatment of the methylated Dhcr7 promoter with the demethylating agent, 5-aza-2'-deoxycytidine (5-Aza-CdR), reversed the suppression of promoter activity. These results indicate that methylation of the CpG islands is an important transcriptional regulatory mechanism in the Dhcr7 promoter.

• Journal of Microbiology and Biotechnology
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• 제24권10호
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• pp.1438-1444
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• 2014

Lactic acid bacteria (LAB) are probiotics that provide numerous beneficial effects on the host body, especially on the intestine. Combining several strains of LAB, we prepared a formulation containing four different LAB and studied its anti-inflammatory activity both in vitro and in vivo. The formulation significantly reduced NO production from RAW 264.7 cells treated with bacterial lipopolysaccharide, indicating that the formulation might include anti-inflammatory activity. The formulation also suppressed inflammatory change induced by trinitrobenzene sulfonic acid (TNBS) in mice, where oral or rectal administration of the formulation protected the colon tissue from the damage by TNBS. Expressions of the IL-6 and FasL genes appeared to be down-regulated by the formulation in TNBS-treated colon tissues, suggesting that the suppression of those genes may be involved in the anti-inflammatory activity of the formulation.

• 한방안이비인후피부과학회지
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• 제22권2호
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• pp.104-117
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• 2009

Objective : Melanin is one of the most important facor in skin color. Melanin protects human skin from ultraviolet radiation otherwise it causes melanin pigmentation. So this experiment is carried out for test whether Scutellaria baicalensis Georgi(SBG) inhibits melanin synthesis and tyrosinase activity in mouse B16 melanoma cells. Method : The melanin synthesis inhibition effects of SBG were examined by in vitro melanin production assay. We assessed inhibitory effects of SBG on melanin contents from B16F1 melanoma cell, on tyrosinase activity(cell and cell free system), effect of SBG on the expression tyrosinase, Microphthalmia-associated Transcription Factor(MITF), Extracellular signal-regulated Kinase(ERK). Result : SBG inhibited melanin synthesis induced $\alpha$-MSH($\alpha$-Melanin Stimulating Hormone) in B16F1. SBG inhibited tyrosinase activity and expression. And SBG down-regulates MITF and stimulated ERK activation in B16F1. Conclusion : According to above results, SBG was improved its suppression effect to the inhibition of melanin synthesis, tyrosinase activation, and tyrosinase promotor activation. So SBG is considered to be used for an strong source of skin whitening effect.