• Title/Summary/Keyword: Inhibiting Effect

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Studies on Staphylococci Isolated from Bovine Mastitis: III. Activity of Penicillins and Gentamicin to Isolates (젖소 유방유래(乳房由來) 난포구원(蘭葡球園)에 관한 연구(硏究) : III. 분리균주(分離菌株)에 대한 Penicillins 및 Gentamicin의 항균효과(抗菌效果))

  • Park, Cheong-kyu
    • Korean Journal of Veterinary Research
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    • v.24 no.2
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    • pp.163-168
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    • 1984
  • The in vitro activity of penicillins(penicillin G, ampicillin, carbenicillin, methicillin and cloxacillin) and gentamicin to Staphylococcus aureus and coagulase-negative staphylococci isolated from bovine mastitic milk samples was determined. The growth of all isolates of staphylococci tested was inhibited by cloxacillin and methicillin at a concentration of $0.78{\mu}g/ml$ and by gentamicin at a minimum inhibitory concentration (MIC) of $1.56{\mu}g/ml$. Of the 140 strains of Staphylococcus aureus isolated 99(70.7%) gave positive reactions for penicillinase on the starch-iodine test. Of 121 isolates of coagulase-negative staphylococci, 58(47.9%) showed penicillinase production, but all the Staph. xylosus lacked the ability to produce penicillinase. MIC of penicillin G of the penicillinase-positive strains was $0.2{\mu}g/ml$ or more. The combination of cloxacillin with gentamicin showed a synergistic effect by inhibiting regrowth of the tested organism.

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Stimulation of Tissue Transglutaminase Activity by Clostridium botulinum Neurotoxin Type B

  • Moon, Yu-Seok;Gi-Hyeok;Rhee, Sang-Dal;Jung, Hyun-Ho
    • Journal of Microbiology
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    • v.41 no.2
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    • pp.161-164
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    • 2003
  • Recombinant light chain of Clostridium botulinum neurotoxin type B stimulated transglutaminase activity in a dose dependent manner, Compared to native toxin, recombinant light chain showed av greater stimulatory effect on transglutaminase activity. Zn-chelating agents, inhibiting the proteolytic activity of the clostridial toxins, did not interfere with this stimulation. These results suggest that the light chain plays a major stimulatory role, which is not due to its metallopeptidase activity, but is possibly due to specific interaction with transglutaminase. More importantly, this report provides a new insight into the intracellular action of C. botulinum neurotoxins.

Antifungal Activities of Herbal Essential Oils and Combination Effects with Ketoconazole against Candide spp. (수종 허브정유의 Candida속 진균에 대한 억제 활성 및 Ketoconazole과의 병용효과)

  • 신승원
    • YAKHAK HOEJI
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    • v.46 no.3
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    • pp.203-207
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    • 2002
  • The antifungal activities of the essential oils from Anthemis nobilis, Ciderus atlantica, Juniperus communis, Lavandula angustifolia, Pelargonium graveolens, Pogestemon patchouli, Rosmarinus officinalis, and Styrax tonkinensis which are recommended for the treatment of microbial infections in aromatherapy and complementary medicines were tested against Candida spp. The activities were measured by broth dilution method and disk diffusion assay. Most of the test oils inhibited growth of Candida albicans, C. utilis and C. tropicalis. Especially, the essential oil from Pelargonium graveolens and its main component, citronellol showed the strongest activity among the herbs except benzoic acid from Styrax tonkinensis which is well-known antimicrobial compound. As a result of checkerboard microtiter test. synergistic effect of citronellol, was shown when the component was combinated with ketoconazole, displaying a fractional inhibiting concentration (FIC) index of 0.37 against C. albicans.

Inhibiting Effect of Nicotinic Acid Hydrazide on Corrosion of Aluminum and Mild Steel in Acidic Medium

  • Bhat, J. Ishwara;Alva, Vijaya D.P.
    • Journal of the Korean Chemical Society
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    • v.58 no.1
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    • pp.85-91
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    • 2014
  • The corrosion behavior of aluminum and mild steel in hydrochloric acid medium was studied using a nicotinic acid hydrazide as inhibitor by potentiodynamic polarization, electrochemical impedance spectroscopy technique and gravimetric methods. The effects of inhibitor concentration and temperature were investigated. The experimental results suggested, nicotinic acid hydrazide is a good corrosion inhibitor for both aluminum and mild steel in hydrochloric acid medium and the inhibition efficiency increased with increase in the inhibitor concentration. The polarization studies revealed that nicotinic acid hydrazide exhibits mixed type of inhibition. The inhibition was assumed to occur via adsorption of the inhibitor molecules on the aluminum and mild steel surface and inhibits corrosion by blocking the reaction sites on the surface of aluminum.

Selection of Peptides Binding to HCV E2 and Inhibiting Viral Infectivity

  • Hong, Hye-Won;Lee, Seong-Wook;Myung, Hee-Joon
    • Journal of Microbiology and Biotechnology
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    • v.20 no.12
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    • pp.1769-1771
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    • 2010
  • The envelope glycoprotein E2 of hepatitis C virus (HCV) binds to various cell surface receptors for viral infection. We performed biopanning against this protein and selected peptides from phage display peptide libraries. Two short peptides, pep7-1 and pep12-1, were selected and their ability to inhibit the infection process was investigated. When pep7-1 was present, the infectivity of HCV particles in cell culture was notably decreased. This decrease was demonstrated by Western blot analysis, immunofluorescence assay, and reverse transcription PCR assay. However, pep12-1 showed little inhibitory effect on HCV infection.

Ginseng Prevents DNA-adduct Formation in Rat Hepatocytes in vitro Treated with DMBA

  • Kumar, Ashok
    • Proceedings of the Ginseng society Conference
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    • 1998.06a
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    • pp.263-269
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    • 1998
  • It is an established fact that most of the carcinogens implicate bay-region diol epoxides as the ultimate carcinogenic metabolites. These electrophiles react with nucleophilic sites in the cells to form abducts. It is the formation of carcinogenic-DNA adducts that is thought to initiate carcinogenesis. In our previous study we have reported chemopreventive property of Ginseng on 7,12-dimethylbenz (a)anthracene (DMBA) induced skin papillomagenesis in male Swiss albino mice. In this study we have examined the effect on formation of DMBA-DNA adducts in rat hepatocytes pretreated with ginseng. Primary cultures of rat hepatocytes were used. The cells wets treated with ginseng for 24 hrs and then with DMBA (iOn) for 18 hrs. Cells were then harvested, their DNA was isolated and analyzed by P)2 labelling. A significant reduction in the levels of DMBA-DNA adduces (adducts/108 nucleotides) was observed in all cultures pretreated with ginseng. The viability of cells was not affected by pre-treatment with ginseng. Our finding suggests that ginseng block or suppresses the events associated with chemical carcinogenesis by inhibiting metabolic activation of the carcinogens.

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Research of Energy Efficiency for Power Plant Performance Improvement (발전성능 향상을 위한 에너지 효율 연구)

  • Lee, Jae-Keun;Moon, Jeon-Soo
    • Transactions of the Korean hydrogen and new energy society
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    • v.21 no.3
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    • pp.220-226
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    • 2010
  • The heat transfer performance improvement in closed cooling water system of an electric power generation can be achieved by a corrosion control using corrosion inhibitors. The effect of trisodium phosphate and sodium nitrite upon carbon steel at various $Cl^{-1}$ ion containing water concentrations was examined by an integrated corrosion monitoring system. Nitrite was found to be the most effective inhibitor among tested inhibitors for carbon steel. The inhibiting process is considered as adsorption of nitrite ions in oxide layer which form a passive film on the carbon steel surface.

Modulation of Phytotropin Receptors by Fluoride and ATP

  • Nam, Myung-Hee;Kang, Bin-G.
    • BMB Reports
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    • v.28 no.6
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    • pp.552-555
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    • 1995
  • Treatment of microsomal vesicles isolated from etiolated Pisum sativum L cv. Alaska epicotyl tissue with agents inhibiting protein dephosphorylation, namely NaF and/or ATP, resulted in increased binding of the phytotropin NPA to the putative auxin efflux carriers localized on the plasma membrane. The phytotropin effect was especially conspicuous if the vesicles were simultaneously treated with Triton X-100. Kinetic analysis of the binding indicated the existance of two distinct sites for NPA, each having different affinities. Increased binding of the phytotropin to the membrane where protein dephosphorylation was inhibited was attributable to the increased ligand affinity of both sites. Treatment of tissue segments with flubride was found to enhance in vivo auxin transport. Implications of covalent modification of the auxin efflux carrier complex for the regulation of membrane transport of auxin molecules are discussed.

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Role of GALNT14 in lung metastasis of breast cancer

  • Kim, Mi-Young
    • BMB Reports
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    • v.50 no.5
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    • pp.233-234
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    • 2017
  • Aberrant expression of the polypeptide N-acetyl-galactosaminyltransferase (GALNTs) has been associated with cancer, but their function(s) in metastasis remains elusive. We have recently identified GALNT14, one of the O-GalNAc glycosylation-initiating enzymes, as a prognostic marker for pulmonary relapse in breast cancer patients. Furthermore, we showed that GALNT14 promotes lung metastasis by the following novel mechanisms: 1) enhancing metastasis initiation by inhibiting the anti-metastatic effect of BMP produced from the lung stroma, 2) exploiting growth signals (e.g. FGF) supplied by macrophages, for their growth into macrometastases in the lung environment. These multi-faceted roles of GALNT14 in lung metastasis are achieved by GALNT14-mediated inhibition and activation of the BMP and FGF signaling pathways, respectively. The link among GALNT14, its downstream pathways and lung metastasis, provides us with an opportunity to develop effective therapeutic intervention for breast cancer.

Psammaplin A, a Natural Bromotyrosine Derivative from a Sponge, Possesses the Antibacterial Activity against Methicillin-resistant Staphylococcus aureus and the DNA Gyrase-inhibitory Activity

  • Kim, Do-Yeob;Lee, Il-Sun;Jung, Jee-Hyung;Yang, Sung-Il
    • Archives of Pharmacal Research
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    • v.22 no.1
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    • pp.25-29
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    • 1999
  • Psammaplin A, a natural bromotyrosine derivative from an associated form of two sponges (Poecillastra sp. and jaspis sp.) was found to possess the antimicrobial effect on the Gram-positive bacteria, especially on methicillin-resistant Staphylococcus aureus (MRSA). The minimal inhibitory concentration of psammaplin A against twenty one MRSAs ranged from 0.781 to 6.25 ${\mu}g/ml$, which that of ciprofloxacin was 0.391~3.125${\mu}g/ml$. Psammaplin A could not bind to penicillin binding protein, but inhibited the DNA synthesis and the DNA gyrase activity with the respective 50% (DNA synthesis) and 100% (DNA gyrase) inhibitory concentration 2.83 and 100 ${\mu}g/ml$. These results indicate that psammaplin A has a considerable antibacterial activity, although restricted to a somewhat narrow range of bacteria, probably by inhibiting DNA gyrase.

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