• Title/Summary/Keyword: Inhibitory Activity

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Evaluation of Antimicrobial Activity of Farnesoic Acid Derivatives

  • Kim, Sang-Hee;Oh, Ki-Bong
    • Journal of Microbiology and Biotechnology
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    • v.12 no.6
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    • pp.1006-1009
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    • 2002
  • The biological activities of farnesoic acid derivatives against pathogenic fungi and bacteria were investigated. Farnesoic acid and its derivatives showed growth inhibitory activities against various bacteria. Among the compounds tested, geranylgeranoic acid (3) had potent antibacterial activity against Salmonella typhimurium, Proteus vulgaris, and Bacillus subtilis with minimum inhibitory concentration (MIC) in the range of $6.25-12.5{\mu}g/ml$. On the other hand, amide derivatives of farnesoic acid showed some antifungal activities. In particular, 3,7,11-trimethyl-dodeca-2,6,10-trienoic acid amide (5a) had a potent antifungal activity against Aspergillus niger, Candida albicans, and Trichophyton sp. with MIC in the range of $6.25-12.5{\mu}g/ml$.

Synthesis and Biological Evaluation of Furo[2,3-d]pyrimidines as Akt1 Kinase Inhibitors

  • Kim, Se-Young;Kim, Dong-Jin;Yang, Beom-Seok;Yoo, Kyung-Ho
    • Bulletin of the Korean Chemical Society
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    • v.28 no.7
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    • pp.1114-1118
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    • 2007
  • Based on the hit compound 4 derived from focused library, a series of furo[2,3-d]pyrimidines were designed, synthesized and evaluated for the inhibitory activity against Akt1 kinase. And their structure-activity relationships were investigated. Of these compounds, 3a having 2-thienyl and methyl groups at R1 and R2 showed the most potent activity with an IC50 value of 24 μ M. Introduction of the thienyl groups at C-5 and C- 6 positions significantly improved potency compared to furyl and phenyl groups.

Acyl-CoA: Cholesterol Acyltransferase Inhibitors from llex macropoda

  • Im Kyung-Ran;Jeong Tae-Sook;Kwon Byoung-Mog;Baek Nam-In;Kim Sung-Hoon;Kim Dae-Keun
    • Archives of Pharmacal Research
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    • v.29 no.3
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    • pp.191-194
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    • 2006
  • Twigs from llex macropoda were extracted with MeOH, and the concentrated extracts were partitioned with $CH_2Cl_2$, EtOAc, n-BuOH, and $H_2O$. Repeated column chromatography of the $CH_2Cl_2$ fraction ultimately resulted in the isolation of two compounds, via activity-guided fractionation, using ACAT inhibitory activity measurements. According to the physico-chemical data, the chemical structures of these isolated compounds were identified as lupeol (1) and betulin (2). Compounds 1 and 2 were shown to inhibit the activity of hACAT-1 and hACAT-2 in a dose-dependent manner, and compounds 1 and 2 inhibited hACAT-1 with $IC_{50}$ values of 48 and $83{\mu}M$, respectively.

Effect of Ailanthi Radicis Cortex Extracts on Melanogenesis

  • Cho, Young-Ho
    • Biomedical Science Letters
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    • v.13 no.4
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    • pp.313-317
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    • 2007
  • Melanogenesis refers to the biosynthesis of melanin pigment in melanocytes. Melanogenesis is controlled by the intra- and extracellular environments. In the present study, to develop a new whitening agent, it was investigated the antioxidant activity and the inhibitory effect of Ailanthi Radicis Cortex extract on tyrosinase activity and on melanogenesis in the B16/F1 melanoma cells. The inhibition ratio of tyrosinase activity of ethylacetate fraction from Ailanthi Radicis Cortex was higher than that of arbutin. The ethylacetate fraction showed scavenging activities of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and superoxide anion radicals in a dose dependent manner. The highest inhibitory activity of melanogenesis was also in ethylacetate fraction ($40.0{\pm}5%$ at the concentration of $400{\mu}g/ml$). This study demonstrates that the Ailanthi Radicis Cortex extract might be used to be a potential agent for skin whitening.

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Inhibitory Effects of Bioactive Fractions Containing Protoberberine Alkaloids from the Roots of Coptis japonica on Monoamine Oxidase Activity

  • Lee, Myung-Koo;Lee, Sang-Seon;Ro, Jai-Seup;Lee, Kyong-Soon;Kim, Hack-Seang
    • Natural Product Sciences
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    • v.5 no.4
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    • pp.159-161
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    • 1999
  • The effects of bioactive fractions containing protoberberine alkaloids from Coptis japonica on monoamine oxidase (MAO) activity were investigated. The MAO was obtained from the mitochondrial fraction of mouse brain. The butanol fraction from Coptis japonica was fractionated into separate bioactive fraction (Fr I-IV) by silica gel column chromatography. MAO activity was strongly inhibited by Fr III and IV, which mainly contain protoberberine alkaloids such as berberine, palmatine and coptisine. These results indicated that the protoberberine alkaloids from Coptis japonica had an inhibitory effect on MAO activity.

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Changes of Chloroplast-Mediated Electron Transport Activity and Chlorophyll-Protein Complexes in Barley Seedlings by Decursinol (Decursinol 처리에 따른 보리 유식물의 전자전달 활성과 엽록소-단백질 복합체의 변화에 대하여)

  • 이현식
    • Journal of Plant Biology
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    • v.31 no.2
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    • pp.131-141
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    • 1988
  • The effects of decursinol and decursin on chloroplast-mediated electron transport and phosphorylation in barley seedlings were investigated in comparison with coumarin in the dark or light. The changes of CP-complexes were also studied. Decursinol, decursin and coumarin caused marked inhibitory effects on germination of seed and electron transport and phosphorylation activity of seedlings. The following order of inhibitory effectiveness was exhibited; decursinol>coumarin>decursin. Loss of chlorophyll and decrease of electron transport activity were retarded in the dark, but were reversely accelerated in the light by these three chemicals. The changes of CP-complex patterns were also similar to effects on chlorophyll content and the electron transport activity. These opposite effect in the dark and light suggest that these three chemicals act as natural growth retardants rather than cytokinins or growth inhibitors.

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Antibacterial Phenylpropanoid Gylcosides from Paulownia tomentosa Steud

  • Kang, Kyoung-Hwan;Jang, Seong-Ki;Kim, Bak-Kwang;Park, Man-Ki
    • Archives of Pharmacal Research
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    • v.17 no.6
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    • pp.470-475
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    • 1994
  • The butanol extract of paulownia tomentosa stem showed antibacterial activity against staphyl ococcus aureus (SG511, 285 and 503), Streptococcus pyogenes (A308 and A77) and Streptococcus farcium MD8b etc. The most active compound of the extractg was identified to be campneoside I, which had a minimal inhibitory concentration(MIC) of $150{\;}{\mu}g/ml$ against Strptococcus and Staphylococcus species. From such antibacterial activity, the methoxy group of campneoside I was posulated to be the essential element for the antibacterial activity.

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Antimicrobial Effects of Naringenin alone and in Combination with Related Flavonoids (나린게닌의 항균력에 미치는 관련 후라보노이드의 병용효과)

  • Han, Seong-Sun;Lee, Chong-Kil;Kim, Young-Soe
    • YAKHAK HOEJI
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    • v.36 no.5
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    • pp.407-411
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    • 1992
  • As part of our search for less toxic antimicrobial substances from natural resources, naringin was isolated from feels of Citri fructus and then hydrolyzed to naringenin. The antimicrobial activity of naringenin was examined by measuring the minimal inhibitory concentration(MIC) against fourteen species of bacteria. The antimicrobial activity of narngenin in combination with rutin or hesperetin was evaluated by checkerboard method. Among fourteen species tested, the antimicrobial activity of naringenin was the most prominant against Staphylococcus aureus and Shigella boydii showing MIC of $100\;{\mu}g/ml$ for both species. Combinations of naringenin with rutin or hesperetin showed synergism against several species of bacteria, but no antagonism was observed.

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Antimicrobial Activity of Defatted Camellia(Camellia japonica L.) Seeds Extract (동백(Camellia japonica L.)유박 추출물의 항균활성)

  • 강성구;김용두;최옥자
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.27 no.2
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    • pp.232-238
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    • 1998
  • To developed natural food preservatives, ethanol and water extracts were prepared from the defatted camellia(Camellia japonica L.) seeds. Antimicrobial activities were examined against 14 microorganisms which were food borne pathogens and/or food poisoning microorganisms and food-related bacteria and yeasts. Ethanol extract showed antimicrobial activities against several microorganisms tested, but not on lactic acid bactria. Especially, minimum inhibitory concentrations(MIC) for yeasts were as low as 1mg/ml. Water extract exhibited antimicrobial activities for the yeasts tested, but almost bacteria were not observed. The ethanol extract was fractionated in the order of hexane, chloroform, ethylaetate and butanol fractions to test antimicrobial activity. The strongest activity for the tested yeasts were found in the butanol fractions, but bacteria were chloroform fraction. Hansenula anomala treated with ethanol were observed by scanning electron micrograph, and the results exhibited morphological changes, including the irregularly contracted cell surface and expanded ellipsoidal shape.

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Synthesis of 2,4,6-Tripyridyl Pyridines, and Evaluation of Their Antitumor Cytotoxicity, Topoisomerase I and II Inhibitory Activity, and Structure-activity Relationship

  • Jeong, Byeong-Seon;Choi, Ho-Young;Kwak, Young-Shin;Lee, Eung-Seok
    • Bulletin of the Korean Chemical Society
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    • v.32 no.10
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    • pp.3566-3570
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    • 2011
  • A series of 2,4,6-tripyridyl pyridines were synthesized, and evaluated for their antitumor cytotoxicity, topoisomerase I and II inhibitory activity. From the eighteen prepared compounds, compounds 10-12 have shown better or similar cytotoxicity against several human cancer cell lines as compared to 2,2':6',2"-terpyridine and doxorubicin. Especially, compound 10 exhibited the most potent cytotoxicity better than positive controls. Structure-activity relationship study indicated that 2,2':6',2"-terpyridine skeleton has an important role in displaying significant cytotoxicity against several human cancer cell lines.