• Journal of Microbiology and Biotechnology
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• v.10 no.2
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• pp.181-186
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• 2000

MAPI (microbial alkaline protease inhibitor) was isolated from cultrue broth of Streptomyces chromofuscus SMF28. The Ki values of MAPI for the representative serine proteases such as chymotrypsin and proteinase K were 0.28 and $0.63{\;}\mu\textrm{M}$, respectively, and for the cysteine proteases cathepsin B and papain were 0.66 and $0.28{\;}\mu\textrm{M}$, respectively. These data indicate that MAPI is not a potent selective inhibitor of serine or cysteine proteases. Progress curves for the inhibition of three proteases by MAPI exhibithe characteristic patterns; MAPI exhibited slow-binding inhibition of cathepsin B. It was rapidly associated with chymotrypsin before the addition of substrate and then reactivation of MAPI-inhibited enzyme was investigated in the presence of substrate. On the other hand, MAPI-proteinase K interaction was typical for those classical inhibitors. When MAPI was incubated with trypsin, there was an extensive reduction in the ingibitory activities of MAPI corresponding to 66.5% inactivation of MAPI, indicating that trypsin-like protease may play a role in the decrease of the inhibitory activity during cultivation.

• Corrosion Science and Technology
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• v.16 no.3
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• pp.91-99
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• 2017

The objective of this work was to develop efficient synergistic inhibitor combinations comprising sodium nitrite ($NaNO_2$) and an inhibitor-blend code named (SN-50), keeping in view of their application in industrial cooling water systems. The electrochemical characteristics of the carbon steel working electrode in simulated cooling water (SCW), without and with the addition of different combinations of the inhibitors, were investigated using electrochemical impedance spectroscopy (EIS), open circuit potential (OCP). The electrode surface changes were followed by visual characterization methods. It was demonstrated in this study that all the combinations of the inhibitors exhibited synergistic benefit and higher inhibition efficiencies than did either of the individual inhibitors. The addition of SN-50 inhibitor to the SCW shifted the OCP to more anodic values and increased the polarization resistance ($R_p$) values of carbon steel at all applied concentrations. The higher the applied sodium nitrite concentration (in the protection concentration range), the higher the obtained $R_p$ values and the inhibition efficiency improved by increasing the inhibitor concentration.

• Korean Journal of Child Studies
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• v.29 no.4
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• pp.97-113
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• 2008

In order to examine the antecedents of socially reticent, solitary passive and solitary active behaviors in preschoolers, 38 2 year olds were observed in Kagan's(1989) traditional behavioral inhibition paradigm and thereafter, at age four, in a same age, same sex quartet of peers. Correlation analysis revealed the independent and unique nature of solitary passive, solitary active and reticence behaviors at age 4 suggesting the heterogeneity of the three forms of solitude during the preschool period. Regression analysis indicated that associations between 2 year old inhibition and shyness and 4 year old reticence were positive when mothers demonstrated a high frequency of over protectiveness; similarly, associations between 2 year old inhibition and shyness and 4 year old solitary active behavior were significant and positive when mothers demonstrated high frequencies of authoritarian behavior.

• Preventive Nutrition and Food Science
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• v.16 no.4
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• pp.307-312
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• 2011

In this study, we evaluated the antioxidant activities and xanthine oxidase inhibition effects of water and ethanol extracts of Cynomorium songaricum. The ethanol extract of C. songaricum (EE) contained more phenolic and flavonoid compounds than the water extract (WE). The antioxidant activities of the extracts were increased as the concentration of the extract increased. The WE has better effectiveness than the EE for DPPH free radical scavenging activity and nitrite scavenging ability. The nitrite scavenging abilities of WE were 90.02% ($EC_{50}$ 653.15 ${\mu}g$/mL) at conditions of pH 1.2 and 2,000 ${\mu}g$/mL, and 84.34% ($EC_{50}$ 817.17 ${\mu}g$/mL) at pH 3.0. The EE has more effective SOD-like activity and XO inhibition than WE. The SOD-like activity of EE was 81.47% at a concentration of 2,000 ${\mu}g$/mL, $EC_{50}$ was 951.70 ${\mu}g$/mL. The xanthine oxidase inhibition of the EE, with an $EC_{50}$of 112.47 ${\mu}g$/mL, is greater than that of ascorbic acid, which was 192.50 ${\mu}g$/mL (p<0.05). These results suggest that the C. songaricum is a potentially useful antioxidant source for the development of nutraceuticals and medicines.

• Korean Journal of Pharmacognosy
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• v.16 no.1
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• pp.12-17
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• 1985

The extract of Mawhang-tang showed considerable inhibition of 70.7 and 57.2% at oral doses of 200 and 400mg/kg, respectively, on carrageenin edema in rat paw. In case of combined oral administration of the extract at each dose of 100, 200 and 400mg/kg with 100mg/kg of aspirin, the inhibition percentages were 78.2, 87.2 and 72.5%, respectively. The combined oral administration of 200mg/kg of the extract with 200mg/kg of aspirin exhibited 87.6% inhibition of the edema. On the writhing syndrome induced by 0.7% acetic acid solution, the oral administration of 200mg/kg of the extract with 200mg/kg of aspirin showed remarkable inhibition of 90.3%. In the inhibitory effect of the leakage of dye into peritoneal cavity were shown to be 51.9, 56.6 and 58.1% at the combined administration of the extract at the doses of 100, 200 and 400mg/kg with 100mg/kg of aspirin, respectively.

• Korean Journal of Pharmacognosy
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• v.16 no.1
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• pp.7-11
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• 1985

The extract of Galgun-tang at oral doses of 200 and 400 mg/kg showed remarkable inhibition of 42.5% and 45.0%, respectively, on the carrageenin edema in rat paw. In case of combined oral administration of the extract at each dose of 100, 200 and 400mg/kg with 100mg/kg of aspirin, the inhibitions were 70.5%, 83.6% and 80.7% respectively. These results showed the remarkable effects as compared with those of aspirin which showed 50.3% and 69.4% of inhibition at doses of 100 and 200mg/kg, respectively. On the other hand, on the writhing syndrome in mice induced by 0.7% acetic acid solution, the oral administration of the extract showed remarkable inhibition of 18.5 and 47.7% at doses of 200 and 400mg/kg, respectively. In case of combined oral administration of the extract at each dose of 100, 200 and 400mg/kg with 100mg/kg of aspirin, the inhibition percentages of writhing syndromes were 66.6, 72.3 and 80.8, respectively, whereas the inhibition at doses of 100 and 200mg/kg of aspirin showed 59.9 and 69.5%, respectively.

• Natural Product Sciences
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• v.18 no.1
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• pp.1-7
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• 2012

Among 90 Vietnamese medicinal plant extracts investigated for their antioxidant activity by DPPH assay at various concentrations from $10-100{\mu}g/mL$, 67 showed an inhibition rate over 50% at $100{\mu}g/mL$; 47 had greater than 50% inhibition at $50{\mu}g/mL$; 17 showed over 50% inhibition at $25{\mu}g/mL$. 8 extracts which exhibited strong inhibitory activity more than 50% inhibition at $10{\mu}g/mL$ were further tested for lipid peroxidation inhibition by TBA assay. They displayed activity with $IC_{50}$ values from 30.6 to $158.9{\mu}g/mL$. Until now, this is the first report on antioxidant activity of the female flower of Borassus flabellifer, and the stem of Combretum latifolium, Embelia ribes, Spatholobus parviflorus, and Tetrastigma erubescens. Fractionations of the EtOAc extract prepared from S. parviflorus led to the isolation of protocatechuic acid (1), ferulic acid (2), epicatechin (3), and gallic acid (4). These compounds showed significant DPPH inhibitory activity with $IC_{50}$ values from 6.5 to $23.6{\mu}M$.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.5975-5979
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• 2012

Background: To investigate the influence of telomerase activity, apoptosis, radiosensitivity of cervical cancer after siRNA-mediated knockdown of telomerase RNA and evaluate in vivo growth with gene interference. Methods: We studied siRNA-targeting-telomerase RNA transfection into the Hela cell line. Expression of hTERC mRNA was detected by RT-PCR and telomerase activity was measured by the TRAP assay. Growth inhibition was determined by MTT assay and radiosensitivity of the cervical cancer cells was examined by colony formation assay. In addtion, effects of hTERC inhibition in vivo were studied by injection of siRNA-transfected Hela cells into nude mice. Results: The hTERC siRNA effectively downregulated the expression of hTERC mRNA and also reduced the telomerase activity to 30% of the untreated control vlaue. The viability of hTERC siRNA transfected Hela cells was reduced by 44.7% after transfection. After radiation treatment, the radiosensitivity of Hela cells with hTERC knockdown was increased. In vivo, the tumors developing from the hTERC siRNA-transfected cells were of reduced size, indicating that the hTERT siRNA also depressed the tumorigenic potential of the Hela cells. Conclusions: Our results supported the concept of siRNA-mediated inhibition of telomerase mRNA which could inhibit the expression of hTERC and telomerase activity. Furthermore, radiosensitivity was upregulated after knockdown the hTERC in vivo and in vitro.

• Corrosion Science and Technology
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• v.4 no.5
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• pp.191-200
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• 2005

Two azole compounds viz., Imidazole (IM) and 2-Methylimidazole (2-MIM) were studied to investigate their inhibiting action on corrosion of mild steel in phosphoric acid ($H_3PO_4$) solution by mass loss and polarization techniques at 302K-333K. It has been found that the inhibition efficiency of the all inhibitors increased with increase in inhibitor concentration and decreases with increasing temperature and also with increase in acid concentrations. The inhibition efficiency of these compounds showed very good inhibition efficiency. At 0.5% of IM and 2-MIM in 1N and 5N phosphoric acid solution at 302K to 333K for 5 hours immersion period, the inhibition efficiency of 2-Methylimidazole found to be higher than Imidazole. The adsorption of these compounds on the mild steel surface from the acids has been found to obey Tempkin's adsorption isotherm. The values of activation energy ($E{\alpha}$) and free energy of adsorption (${\Delta}G{\alpha}ds$) were also calculated. The plots of log $W_f$ against time (days) at 302K give straight line which suggested that it obeys first order kinetics and also calculate the rate constant k and half life time $t_{1/2}$. Surface was analyzed by SEM and FITR spectroscopy.

• Biomolecules & Therapeutics
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• v.1 no.1
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• pp.121-124
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• 1993

To elucidate the effect of antipsychotics and antidepressants on phosphoinositide(Pl) second massenger system, we studied the dose-dependent inhibition of the phosphoinositide-specific phospholipase C(PLC) isozymes, ${\beta}_1,\;{\gamma}_1$ and${\delta}_1,$ by fluphenazine and haloperidol as antipsychotics, and amitriptyline, maprotiline and mianserin as antidepressants. All the antipsychotics and antidepressants tested showed inhibition on at least one of the PLC isozymes with $IC_{50}$ at the concentration between 25 and $250 {\mu}M.$ Maprotiline, mianserin and amitriptyline inhibited 80 to 90% of the activities of all three PLC isozymes at the concentration of $250{\mu}M,$ while haloperidol and fluphenazine inhibited PLC ${\beta}_1$ and${\gamma}_1$ But baclofen didn't inhibit any PLC isozyme. These results suggested that PLC isozymes are inhibited by antipsychotics and antidepessants even though the concentration is high, and these drugs may affect PI signal transduction system by direct inhibition of PLC isozymes.