• Applied Biological Chemistry
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• v.46 no.1
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• pp.66-68
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• 2003

• Journal of the Korean Ceramic Society
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• v.35 no.3
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• pp.219-230
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• 1998

Various interlayer materials have been tested for active metal(Cusil ABA) brazing of Si3N4/S. S316 joint. In general multilayer joint had higher strength(80-150 MPa) and better reliability than monolayered one. The joint with Cu(0.2)/Mo(0.3)/Cu(0.2mm) interlayer showed the highest bending strength of abou 490 MPa and the joint with Cu(0.2)/Mo(0.3mm) interlayer the best reliability (14.6 Weibull modulus). The stresses distributed in joint materials during 4-point bending test were estimated by CAE von Mises analysis; the estimated stresses were In good agreement with the measured data. In multilayer joint Cu was though to reduce the residual stresses induced by the difference in thermal expansion coefficient between the ceramic Mo and metal It apperared that a Cu/Mo was optimum interlayer material for Si3N4/S. S316 joint with high bending strength (420 MPa) and reliability. In addition the various shapes and types of compound were examined by EPMA in joining interface.

• BMB Reports
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• v.34 no.1
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• pp.28-32
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• 2001

The Fos-Jun heterodimers are part of the regulatory network of gene expression and nuclear proteins encoded by proto-oncogenes. The activation of Fos-Jun is important in the transmission of the tumor-promoting signal from the extracellular environment to the nuclear transcription mechanism. To search for the inhibitors of the Fos-Jun DNA complex formation, several natural products were screened and water-soluble paeoniflorin reduced the binding activity of the Fos-Jun heterodimer. This active compound was purified by silica gel column chromatography and HPLC. The electrophoresis mobility shift assay and reverse-phase HPLC test showed that paeoniflorin reduced the AP-l function. The cytotoxic effect of paeoniflorin was observed in HL-60. These results indicate that paeoniflorin blocks the Fos-Jun heterodimer-binding site of the AP-l DNA and it also has cytotoxic effects on human leukemia cell lines.

• Korean Journal of Pharmacognosy
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• v.34 no.1 s.132
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• pp.14-17
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• 2003

In the course of screening Korean natural plants for acetylcholinesterase (AChE) inhibitory activity, we found that a methanolic extract of the leaves of Securinega suffruticosa showed significant inhibitory effects on AChE. Bioassay-guided fractionation of the methanolic extract resulted in the isolation of dihydrosecurinine, as a active principle. This compound inhibited AChE activity in a dose-dependent manner, and the $IC_{50}$ value of dihydrosecurinine was $18.9\;{\mu}g$.

• Natural Product Sciences
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• v.22 no.4
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• pp.252-258
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• 2016

Vitex trifolia L. has been used traditionally to treat various illnesses, such as inflammation, headache, migraine, and gastrointestinal infections. We analyzed and evaluated the composition of V. trifolia leaf oil. Based on the results, we isolated abietatriene from V. trifolia leaf oil and investigated the effect of V. trifolia leaf oil and its active compound abietatriene on melanogenesis in B16F10 melanoma cells. They significantly decreased melanin contents and melanogenic factors, such as tyrosinase, TRP-1, TRP-2, and MITF dose-dependently in both protein and mRNA levels. Protein and mRNA expressions were determined by Western blot analysis and quantitative real time RT-PCR. Findings indicate that V. trifolia leaf oil and abietatriene reduce melanogenesis by regulating the expression of melanogenic factors. These results suggest that V. trifolia leaf oil and abietatriene could comprise a useful therapeutic agent for treating hyperpigmentation and used as effective skin-whitening agents.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1176-1181
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• 2004

The cytotoxic activities of Cinnamomum cassia (Blume) bark-derived materials toward six human HeLa epithelioid cervix, A549 lung, SK-OV-3 ovarian, SK-MEL-2 melanoma, XF-498 central nerve system, and HCT-15 colon tumor cell lines were evaluated by using sulforhodamine B assay and compared to those of the anticancer agents, cisplatin and mitomycin C. The biologically active constituent of the Cinnamomum bark was characterized as trans­cinnamaldehyde by spectroscopic analysis. The cytotoxic activity of cinnamaldehyde against HeLa, SK-MEL-2, and HCT -15 cell lines was comparable to that of cisplatin and mitomycin C. The compound showed lower activity against A549, SK-OV-3, and XF-498 cell lines than the anticancer agents. Eugenol exhibited moderate activity against SK-OV­3, XF-498, and HCT-15 tumor cells, and trans-cinnamic acid, cinnamyl alcohol, $\alpha-pinene,\;and\;\beta-pinene$ showed little or no activity against model tumor cells. Cinnamaldehyde was not mutagenic against four strains (TA 98, TA 100, TA 1535, and TA 1537) of Salmonella typhimurium (Castel and Chalm). These results indicate at least one pharmacological action of C. cassia.

• Microbiology and Biotechnology Letters
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• v.23 no.6
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• pp.641-646
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• 1995

During the screening of inhibitors of melanin biosynthesis from microbial secondary metabolites, a fungal strain MR304 which was capable of producing high level of an inhibitor was selected. Based on taxonomic studies, this fungus could be classified as Trichoderma harzianum. The active compound (MR304-1) was purified from culture broth by Diaion HP-20 column chromatography, ethylacetate extraction, Sephadex LH-20 column chromatographv and HPLC. The inhibitor was identified as 3-(1,5-dihvdroxy-3-isocyanocyclopent-(E)-3-envl)prop-2-enoate by spectroscopic methods of UV, ESIMS, $^{1}$H-NMR, $^{13}$C-NMR, NOE, HMQC and HMBC. MR304-1 showed strong mushroom tyrosinase inhibitory activity with IC$_{50}$ value of 0.25 $\mu $g/ml. It inhibited melanin biosynthesis with 15 mm inhibition zone at 30 $\mu $g/paper disc in Streptomyces bikiniensis, a bacterium used as an indicator organism in this work. It also inhibited melanin biosynthesis in B16 melanoma cells with a niinimum inhibitory concentration of 0.05 $\mu $g/ml.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.5
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• pp.468-475
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• 2009

This study was conducted to examine the bleaching of an anti-inflammatory agent containing Undaria pinnatifida extract (AIAU). Brown-colored AIAU was irradiated with $^{60}CO$ gamma rays at doses ranging from 10-200 kGy. Discoloring of the anti-inflammatory agent was achieved by gamma irradiation, with significantly removal by 50 kGy irradiation. The main active compound of the agent consisted of 4% U. pinnatifida extract, which inhibited inflammatory symptoms in mouse ear edema by 93%. There was no change in effects against edema, erythema, blood flow and radical scavenging activity by irradiation.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7601-7605
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• 2013

Background: Gambogenic acid is a major active compound of gamboge which exudes from the Garcinia hanburyi tree. Gambogenic acid anti-cancer activity in vitro has been reported in several studies, including an A549 nude mouse model. However, the mechanisms of action remain unclear. Methods: We used nude mouse models to detect the effect of gambogenic acid on breast tumors, analyzing expression of apoptosis-related proteins in vivo by Western blotting. Effects on cell proliferation, apoptosis and apoptosis-related proteins in MDA-MB-231 cells were detected by MTT, flow cytometry and Western blotting. Inhibitors of caspase-3,-8,-9 were also used to detect effects on caspase family members. Results: We found that gambogenic acid suppressed breast tumor growth in vivo, in association with increased expression of Fas and cleaved caspase-3,-8,-9 and bax, as well as decrease in the anti-apoptotic protein bcl-2. Gambogenic acid inhibited cell proliferation and induced cell apoptosis in a concentration-dependent manner. Conclusion: Our observations suggested that Gambogenic acid suppressed breast cancer MDA-MB-231 cell growth by mediating apoptosis through death receptor and mitochondrial pathways in vivo and in vitro.

• Microbiology and Biotechnology Letters
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• v.19 no.4
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• pp.337-342
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• 1991

A bacterium producing the antifungal compound KRF-001 isolated from soil was selected and identified as Bacillus subtilis. The antibiotic KRF-001 was active against various fungi. Effecacy of KRF-001 at various concentration for controlling leaf blast of rice in the paddy field was evaluated and compared with recommended rates of kasugamycin, blasticidin- s and tricyclazole. KRF-001 caused no irritation on the skin of rabbits and LD50 for mice was deduced more than 5000 mg/kg which indicates the possibility of low toxicity or no toxicity.