• Natural Product Sciences
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• v.5 no.2
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• pp.65-69
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• 1999

By bioassay guided fractionation followed by chromatographic separation of the MeOH extract from the fruit of Evodia rutaecarpa (Juss.) Benth. (Rutaceae), a new cyclooxygenase-2 inhibitor was isolated and identified as an alkaloid, rutaecarpine. Other alkaloids such as evodiamine and dehydroevodiamine together with limonoids were also isolated and characterized.

• Applied Biological Chemistry
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• v.43 no.2
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• pp.158-161
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• 2000

• Journal of Microbiology and Biotechnology
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• v.25 no.9
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• pp.1425-1428
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• 2015

Monoamine oxidase (MAO) is found in most cell types and catalyzes the oxidation of monoamines. Three anithiactins (A-C, modified 2-phenylthiazoles) isolated from Streptomyces sp. were tested for inhibitory activity of two isoforms, MAO-A and MAO-B. Anithiactin A was effective and selective for the inhibition of MAO-A, with an IC₅₀ value of 13.0 μM; however, it was not effective for the inhibition of MAO-B. Anithiactins B and C were weaker inhibitors for MAO-A and MAO-B. Anithiactin A was a reversible and competitive inhibitor for MAO-A with a K_i value of 1.84 μM. The hydrophobic methyl substituent in anithiactin A may play an important role in the inhibition of MAO-A. It is suggested that anithiactin A is a selective reversible inhibitor for MAO-A, with moderate potency, and can be considered a new potential lead compound for further development of novel reversible inhibitors for MAO-A.

• The Korean Journal of Food And Nutrition
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• v.21 no.2
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• pp.143-147
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• 2008

To develop a new anti-wrinkle agent from medicinal plants, this study investigated the optimal conditions for extracting elastase inhibitor from Rheum undulatum L. Maximal extraction occurred by using 70% methanol at $50^{\circ}C$ for 24 hr; the elastase inhibitory activity was 60.4%($IC_{50}:6.7{\times}10^3{\mu}g/m{\ell}$). Systematic solvent extraction, thin layer chromatography, silica gel column chromatography, Sephadex LH-20 column chromatography, and reverse-phase high performance liquid chromatography were used in the partial purification of the elastase inhibitor. The compound was soluble in dimethylsulfoxide, methanol, and ethanol, and had maximum absorption spectra at 231.5 nm and 275.5 nm.

• Biomolecules & Therapeutics
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• v.21 no.2
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• pp.107-113
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• 2013

Plasminogen activator inhibitor-1 (PAI-1) is a member of serine protease inhibitor family, which regulates the activity of tissue plasminogen activator (tPA). In CNS, tPA/PAI-1 activity is involved in the regulation of a variety of cellular processes such as neuronal development, synaptic plasticity and cell survival. To gain a more insights into the regulatory mechanism modulating tPA/PAI-1 activity in brain, we investigated the effects of proteasome inhibitors on tPA/PAI-1 expression and activity in rat primary astrocytes, the major cell type expressing both tPA and PAI-1. We found that submicromolar concentration of MG132, a cell permeable peptide-aldehyde inhibitor of ubiquitin proteasome pathway selectively upregulates PAI-1 expression. Upregulation of PAI-1 mRNA as well as increased PAI-1 promoter reporter activity suggested that MG132 transcriptionally increased PAI-1 expression. The induction of PAI-1 downregulated tPA activity in rat primary astrocytes. Another proteasome inhibitor lactacystin similarly increased the expression of PAI-1 in rat primary astrocytes. MG132 activated MAPK pathways as well as PI3K/Akt pathways. Inhibitors of these signaling pathways reduced MG132-mediated upregulation of PAI-1 in varying degrees and most prominent effects were observed with SB203580, a p38 MAPK pathway inhibitor. The regulation of tPA/PAI-1 activity by proteasome inhibitor in rat primary astrocytes may underlie the observed CNS effects of MG132 such as neuroprotection.

• KSBB Journal
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• v.4 no.2
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• pp.123-127
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• 1989

The separation of trypsin inhibitir using reverse micellar system was invertigated. Among the biffer system tested, 1.0M $CaCl_2$ solution (pH 3.0) and 1.0M NaCl soluation (pH 11.5) were most effective for solubilization and de-solubilization of protein, respectively. When these conditions were applied to two model sampeles, one of which was composed of the same amount of 7S protein and trpsin inhibitor, and the other of which was composed of the same amount of soluble soybean protein isolates and trypsin inhibitor, highly pure trypsin inhibitor was obtained. And in the real soybean, Kwng Gyo, pure trypsin inhibior was also obtained.

• Journal of Applied Reliability
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• v.17 no.2
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• pp.122-128
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• 2017

Purpose: To investigate the corrosion inhibition effect of the natural spearmint oil extracted from Mentha Spicata plants on 304 stainless steel in different concentrations of hydrochloric acid. Method: The anti-corrosive effect has been investigated in 0.5m, 1m and 2m HCl using weight loss test and electrochemical polarization method as a function of inhibitor concentration and immersion time in strong chloride environment. The surface morphology was analysed by scanning electron microscopy (SEM). Results: The corrosion rate of steel decreased and inhibition efficiency increased with the increase in inhibitor concentration. Microscopic evaluation revealed significant corrosion in the specimens immersed in uninhibited conditions. Potentiodynamic polarization test results showed an increase in corrosion potential (Ecorr) and decrease in corrosion current (icorr) value with increasing concentration of inhibitor. Conclusions: Immersion of steel in higher concentration of inhibitor resulted in greater surface coverage value and hence lesser number of surface corrosion sites/pores were formed; thus lowering the corrosion rate.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.383.2-383.2
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• 2002

Diabetic nephropathy is major chronic complication of diabetes mellitus. Advanced glycation endproducts(AGEs) are largely involved in the pathogenesis of diabetic nephropathy. The irreversibly formed AGEs do not return to normal even if hyperglycemia is corrected and continue to accumulate over the lifetime of protein. The AGEs inhibitor. aminoguanidine(AG), is the only protein glycation inhibitor currently under development. its safety however is desirable. To find possible AGEs inhibitor in herbal medicines, bovine serum albumin was added to a mixture of sugars and some of processed. unprocessed herbal medicines or AG. Cyperi rhizoma was processed in four different methods according to chinese pharmacopoeia and traditional literatures. In comparision to the negative control with no inhibitor and positive control with AG. alcoholic extracts of these processed cyperi rhizoma proved to have more potent inhibitory activities than that of unprocessed cyperi rhizoma. These results revealed that some processed herbal medicines have a more potent in vitro inhibitory action on AGEs formation than AG. suggesting the possible candidate for diabetic nephropathy from the processed herbal medicines.

• Environmental Analysis Health and Toxicology
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• v.20 no.1
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• pp.75-85
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• 2005

This study was aimed to know the effect of cadmium chloride (CdCl₂) on glucose transport in L6 myotube and its action mechanism. CdCl₂ increased the 2-deoxy- (l-3H)-D-glucose (2-DOG) uptake 1.9 and 2.4 fold at 10 and 25 μM respectively. To investigate the stimulating-mechanism of glucose transport induced by CdCl₂, the wortmannin and PD98059 were used as PI3K (phosphatidylinositol 3-kinase) inhibitor and MAPK inhibitor respectively, which did not affect 2-DOG uptake. This fact suggests that CdCl₂ induced 2-DOG uptake may not be concerned to the insulin signalling pathway. Whereas nifedipine, a calcium channel blocker, and trifluoperazine, a calmodulin inhibitor, were found to inhibit the 2-DOG uptake stimulted by CdCl₂. In addition, we also measured the ROS (reactive oxygen species) production and GSH level in L6 myotube to investigate the correlation between the glucose uptake and ROS. CdCl₂(25 μM) increased ROS generation approximately 1.5 fold and changed the cellular GSH level, but GSSG/GSH ratio remained unchanged. CdCl₂ stimulated 2-DOG uptake and ROS generation were inhibited by N-acetylcystein. And BSO pretreatment, a potent inhibitor of γ-GCS, resulted in the dramatic decrease of 2-DOG uptake and also the increase of the sensitivity to cadmium cytotoxicity. The obtained results suggest that CdCl₂-stimulated glucose uptake might be based on the activation of HMP shunt as an antioxidant defense mechanism of the cells.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.2
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• pp.93-99
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• 2014

The present study prepared 13 mixes to examine fundamental mixture proportions of corrosion inhibitor repair mortars. The mortar mixes were classified into three groups according to the selected test variables which are the substitution level of polymer for Group 1, ground granulated blast-furnace slag (GGBS) and fly ash (FA) for Group 2, and corrosion inhibitor for Group 3. Based on the test results, the optimum substitution levels of GGBS and FA could be recommended as 10% and 20%, respectively, though 1-day strength of mortar significantly decreased with their substitution. Furthermore, the appropriate substitution level of corrosion inhibitor was considered to be less than 1.5%. The flexural strength of mortar tested was higher than the predictions obtained from ACI 318-11 equation. The shrinkage strain of mortar was also conservative after an age of around 10 days compared with the predictions of ACI 209.