• Asian Pacific Journal of Cancer Prevention
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• v.17 no.3
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• pp.957-963
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• 2016

Cellular senescence, a barrier to tumorigenesis, controls aberrant proliferation of cells. We here aimed to investigate cellular senescence in immortalized cholangiocyte and cholangiocarcinoma cell lines using five different inducing agents: 5-aza-2'deoxycytidine, bromodeoxyuridine, interferons ($IFN{\beta}$ and $IFN{\gamma}$), and hydrogen peroxide. We analyzed senescence characteristics, colony formation ability, expression of genes involved in cell cycling and interferon signaling pathways, and protein levels. Treatment with all five agents decreased cell proliferation and induced cellular senescence in immortalized cholangiocyte and cholangiocarcinoma cell lines with different degrees of growth-inhibitory effects depending on cell type and origin. Bromodeoxyuridine gave the strongest stimulus to inhibit growth and induce senescence in most cell lines tested. Expression of p21 and interferon related genes was upregulated in most conditions. The fact that bromodeoxyuridine had the strongest effects on growth inhibition and senescence induction implies that senescence in cholangiocarcinoma cells is likely controlled by DNA damage response pathways relating to the p53/p21 signaling. In addition, interferon signaling pathways may partly regulate this mechanism in cholangiocarcinoma cells.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.1
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• pp.124-129
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• 2005

Resveratrol, a phytoalexin found at high levels in grapes and in grape products such as red wine, has been reported to possess a wide range of biological and pharmacological activities including anti-oxident, anti-inflammatory, anti-mutagenic, and anti-carcinogenic effects, but its molecular mechanism is poorly understood. In this study, we examined the effects of resveratrol on lipopolysaccharide (LPS)-induced growth inhibitory activity and cell growth-regulatory gene products in astroglioma C6 cells to elucidate its possible mechanism for anti-cytotoxicity. It is shown that LPS induced time-dependent growth inhibition and morphological changes of C6 cells, which were recovered by pre-treatment with resveratrol. The anti-proliferative effect of LPS was associated with the induction of tumor suppressor p53 and cyclin-dependent kinase (Cdk) inhibitor p21 (WAF1/CIP1) expression assessed by RT-PCR and Western blot analysis in time-dependent manner in C6 cells. In addition, the pro-apoptotic Bax expression was also up-regulated in LPS-treated C6 cells without alteration of anti-apoptotic Bcl-2 and Bcl-XL expression. However, resveratrol significantly inhibited LPS-induced p53, p21 and Bax levels, suggesting that the modulation of p53, p21 and Bax levels could be one of the possible pathways by which resveratrol functions as anti-cytotoxic agent.

• Korean Journal of Weed Science
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• v.17 no.4
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• pp.407-412
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• 1997

Allelopathic activity of methanol extract from medicinal plants was determined based on the inhibition of germination, shoot and root length of Echinochloa crus-galli. The response was depended on the source of extracts and concentrations. Of the 20 test plants tested, Cnidium officinale showed most inhibition according to germination, shoot and root length of E. crus-galli. Based on the plant parts, the root extract of C. officinale had more inhibitory effect on E. crus-galli than the stem+leaf extract. Phytotoxic effects of the root extract on E. crus-galli showed 75% inhibition of seed germination, 95% inhibition of shoot growth, and 100% inhibition of root growth at the concentration of 1g/petridish. Sequential partitioning of root extract with organic solvents with increasing polarity showed that the ethylacetate fraction had the greatest inhibitory effect on E. crus-galli. Germination was not inhibited at any rate of ethylacetate fraction but shoot and root growth, were significantly inhibited even at 2mg/petridish. This indicates that the most toxic phytotoxin present in the root extract may be moderate polar compound.

• Archives of Pharmacal Research
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• v.28 no.11
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• pp.1270-1274
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• 2005

The vascular endothelial growth factor (VEGF) plays a key role in angiogenesis, which is a process where new blood vessels develop from the endothelium of a pre-existing vasculature. VEGF exerts its activity by binding to its receptor tyrosine kinase, KDR/Flk-1, which is expressed on the surface of endothelial cells. A methanol extract and organic solvent (n-hexane, ethyl acetate, n-butanol, aqueous) fractions from Rubus coreanus were examined for their inhibitory effects on VEGF binding to the VEGF receptor. The methanol extract from the crude drug were found to significantly inhibit VEGF binding to the VEGF receptor ($IC_{50}$$\thickapprox$27 $\mu$g/mL). Among the fractions examined, the aqueous fraction from the medicinal plant showed potent inhibitory effects against the binding of KDR/Flk-1-Fc to immobilized $VEGF_{165}$ in a dose­dependent manner ($IC_{50}$$\thickapprox$11 $\mu$g/mL). Sanguiin H-6 was isolated as an active principle from the aqueous fraction, and inhibited the binding of KDR/Flk-1-Fc to immobilized $VEGF_{165}$ in a dose­dependent manner ($IC_{50}$$\thickapprox$0.3 $\mu$g/mL). In addition, sanguiin H-6 efficiently blocked the VEGF­induced HUVEC proliferation in a dose-dependent manner ($IC_{50}$$\thickapprox$7.4 $\mu$g/mL) but had no effect on the growth of HT1080 human fibrosarcoma cells. This suggests that sanguiin H-6 might be a potential anti-angiogenic agent.

• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.370-374
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• 1991

The inhibitory effects of garlic on the mutagenicity in Salmonella assay system and on the growth of HT-29 human colon carcinoma cells were studied. Methanol extract of garlic inhibited the mutagenicities induced by aflatoxin $B_1(AFB_1)$and N-methyl-N'-nitro-N-nitrosoguanidine(MNNG) in Salmonella typhimurium TA100. The inhibition rate increased significantly when the concentration of the methanol extract from garlic increased in both strains of Salmonella typhimurium TA98 and TA100. The chloroform fraction from the methanol extract exhibited strong antimutagenicity against $AFB_1$. The chloroform fraction also inhibited greatly the growth of human HT-29 colon carcinoma cells in fetal bovine serum concentrations of 1% and 5%.

• The Korean Journal of Ecology
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• v.12 no.3
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• pp.161-170
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• 1989

To verify allelopathic effects of Artemisia princeps var. orientalis, a number of laboratory experiments have been performed. Aqueous extracts of leaves, stems and roots of the above species inhibited the seed germination and seedling growth of experimental species, receptor plants. In general, the higher was the concentration of the extracts, the lower was the germination and the growth ratio. Volatile substances released from leaves of the donor plants also inhibited the seed germination and the radicle elongation of receptor plants. Therefore, to find out the inhibitory substances emitted from the wormwood, gas chromatography was employed. As a result of the analysis, 17 KDICical substances were isolated from the leaves and most of them were identified as phenolic compounds.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.4
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• pp.303-307
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• 2003

Some Compositae plants are known to contain biologically active substances that are allelopathic to weeds species as well as antioxidant to foods. Aqueous extracts from leaves of 3 plant species, Cirsium japonica, Kalimeris yomena, and Lactuca saliva, were bioassayed against alfalfa (Medicago saliva) to determine their allelopathic effects. The extracts applied on filter paper in bioassay significantly inhibited root growth of alfalfa. Extracts of 20 g dry tissue $\textrm{L}^{-1}$ from Lactuca sativa showed the most inhibitory effect on alfalfa seedling growth and followed by Cirsium japonica and Kalimeris yomena. Oxidative stability by Rancimat method and antioxidant activity by TBA method for the ground samples were the greatest in Lactuca sativa although were less than that of a commonly used antioxidant, 1% ascorbic acid. Antioxidant activity of methanol extracts on storing meat was stably kept for 28days and was excellent compared to control. These results suggest that three Compositae plants have potent allelopathic and antioxidant effects, and that their activities differ, depending on plant species.

• Microbiology and Biotechnology Letters
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• v.25 no.5
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• pp.442-447
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• 1997

To development food preservative, antimicrobial activities of Schizandra chinensis (SC) against Listeria monocytogenes Scott A, L. monocytogenes Brie I and L. monocytogenes ATCC 19111 were investigated. The growth of L. monocytogenes Scott A, L. monocytogenes Brie I and L. monocytogenes ATCC 19111 was inhibited apparently in Tryptic Soy Broth (TSB) containing 1% SC at 35$\circ$C and it was found that these had antibacterial effects against a broad spectrum of pathogenic bacteria such as S. aureus ATCC 29737, B. subtilis KCTC 1021, E. coli ATCC 11775. The growth of L. monocytogenes was also inhibited about 3 to 5 log$_{10}$ cycle by 0.1% of three fractions of the alcohol extract such as ether, ethyl acetate and butanol. Acidic, weakly acid and neutral fraction of ether fraction showed inhibitory properties against L. monocytogenes.

• International Journal of Oral Biology
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• v.35 no.4
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• pp.203-207
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• 2010

A number of bacterial species coexist in oral cavities as a biofilm rather than a planktonic arrangement. By forming an oral biofilm with quorum sensing properties, microorganisms can develop a higher pathogenic potential and stronger resistance to the host immune system and antibiotics. Hence, the inhibition of biofilm formation has become a major research issue for the future prevention and treatment of oral diseases. In this study, we investigated the effects of pentose on biofilm formation and phenotypic changes using wild type oral bacteria obtained from healthy human saliva. D-ribose and D-arabinose were found to inhibit biofilm formation, but have no effects on the growth of each oral bacterium tested. Pentoses may thus be good candidate biofilm inhibitors without growth-inhibition activity and be employed for the future prevention or treatment of oral diseases.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.2
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• pp.239-243
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• 1998

The growth of pathogens such as Staphylococcus aureus ATCC 29737, Bacillus subtilis KCTC 1021 and Escherichia coli ATCC 11775 was inhibited as much as 1 to 4 log cycles in tryptic soy broth containing 1% of Schizandra chinensis extract but Salmonella tuphimrium ATCC 14028 and Vibrio parahaemolyticus ATCC 17802 were not inhibited. The essential oil of Schizandra chinensis showed stronger inhibitory activity than ethanol extract against above menioned pathogens. The growth of Listeria monocytogenes was not changed in minced pork containing 1% of Schizandra chinensis extract for 12 days at 4$^{\circ}C$. The sensory quality of hamburger patty such as taste, flavor and overall accepability were not decreased by the addition of 1% Schizandra chinensis extract(p<0.05).