• The Korean Journal of Food And Nutrition
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• v.11 no.6
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• pp.673-677
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• 1998

A inhibitor acting on substrate proteolytic enzyme was isolated from culture broth of Streptomyces sp. SK-862, which had been isolated from soil in Wonju City, by using the colloidal agar medium. The optimum culture temperature and initial pH for the production of the protease inhibitor was 28$^{\circ}C$ and pH 8.5, respectively. The optimum culture medium was composed of 1.5% glucose, 0.5% peptone, 0.1% K2PHO4, 0.05% CaCO3 and initial pH 8.5. The inhibitor production was maximum when the strain was incubated in shaking incubator at 70 strokes for 60 hours.

• YAKHAK HOEJI
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• v.42 no.6
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• pp.552-557
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• 1998

Acyl CoA synthetase inhibitor, was purified from the culture broth of a Bacillus sp. B-6, which had been isolated from soil, by chloroform extract, silica gel column chro matography and preparative TLC. The purified acyl CoA synthetase inhibitor showed higher Antifungal activity against C. al-bicans (MIC: 8${\mu}$g/ml). Though the analysis of UV spectrum, melting point, IR spectrum, Mass-spectrum, $^1H$-NMR and $^{13}C$-NMR spectrum, the inhibitor could be identified as phenazine-l-carboxylic acid.

• 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.

• Microbiology and Biotechnology Letters
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• v.17 no.3
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• pp.207-212
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• 1989

Cultural conditions for $\alpha$-D-Glucosidase Inhibitor production from Streptomyces sp. YS-221-B isolated from soil arid identified as Streptomyces flauovirens or a subspecies of it were investigated. When the strain was cultured in a flask containing 2% glucose, 0.3% asparagine, 0.0002% riboflavin, 0.05% $K_2$HPO$_4$, 0.1% MgSO$_4$.7$H_2O$, 0.05% NaCl, pH 8.0 at 3$0^{\circ}C$, maximum production of the inhibitor was obtained after 8-9 days of cultivation. Sugar alcohols such as mannitol, i-inositol, erythritol as carbon sources, asparagine and beef extract as nitrogen sources were favorable for inhibitor production. Among vitamins, riboflavin, p-aminobenzoic acid, pyridoxamine and folic acid promoted the production of inhibitor, but depressed by the addition of hesperidine, and also depressed by cobalt, lithium and ferrous salts.

• Archives of Pharmacal Research
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• v.25 no.4
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• pp.463-468
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• 2002

We have previously reported on the identification of the endogenous transmethylation inhibitor oligosaccharide-linked acyl carrier protein (O-ACP), In this study, the role of the transmethylation reaction on cell cycle progression was evaluated using various transmethylase inhibitors, including O-ACP. O-ACP significantly inhibited the growth of various cancer cell lines, including NIH3T3, ras-transformed NIH3T3, MDA-MB-231, HT-1376, and AGS. In addition, exposure of ras-transformed NIH3T3 to O-ACP caused cell cycle arrest at the $G_0/G_1$ phase, which led to a decrease in cells at the S phase, as determined by flow cytometry. In contrast, transmethylase inhibitors did not affect the expression of $p21^{WAF1/Cip1}$, a well known inhibitor of cyclin dependent kinase, indicating that the cell cycle arrest by transmethylase inhibitors might be mediated by a $p21^{WAF1/Cip1}$-independent mechanism. Therefore, O-ACP, a novel transmethylase inhibitor, could be a useful tool for elucidating the novel role of methylation in cell proliferation and cell cycle progression.

• The Journal of Natural Sciences
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• v.4
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• pp.23-28
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• 1991

The pyrimidy1 derivative of 2'-deoxythmidine 5'-monophosphate, 3 has been synthesized for the development of anticanncer agents. The compound 3 derived from prototype inhibitor 2 by modifying the p-aminobenzoy1 glutamic acid portion has been designed to facilitate the membrane penetration. Variable temperature $^1H$ NMR spectrum for the protected nucleotide has indicated the existence of two conformers which are stable on the NMR time scale at ambient temperature.

• Microbiology and Biotechnology Letters
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• v.10 no.4
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• pp.283-288
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• 1982

Trypsin inhibitor produced by Streptomyces sp. was investigated its reactive characteristics against trypsin. The mode of inhibition against trypsin was mixed type of non-competitive and competitive with casein, and enzyme-inhibitor complex was formed rapidly. The inhibitory activity was increased by the addition of isoleucine and depressed by silver, mercuric or cupric ion. And when egg albumin or hemoglobin was used as substrate for trypsin, the inhibition ratio was changed. The inhibitor inhibited coagulation of blood of bovine.

• Microbiology and Biotechnology Letters
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• v.22 no.5
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• pp.495-498
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• 1994

Genistein, a inhibitor of the progression of G$_{1}$ and G$_{2}$ phase of the mammalian cell cycle, was discovered through a unique screening system, in which effects of microbial metabolites on the cycle progression of the cultured mouse mammalian carcinoma cell were monitored by flow cytometry. The inhibitor was extracted from the fermentation broth of Streptomyces sp. ZF10 with ethyl acetate, and purified by silica gel column chromatography and HPLC.

• Biomedical Science Letters
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• v.22 no.2
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• pp.60-64
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• 2016

In the pathogenesis of inflammatory diseases such as allergies, S100A8 acts as an important molecule and T lymphocytes are essential cytokine-releasing cells. In this study, we investigated the effect of S100A8 on release of cytokines, specifically MCP-1, IL-6, and IL-8 in T cells, and its associated signaling mechanism. S100A8 increased secretion of MCP-1, IL-6, and IL-8 in a time- and dose-dependent manner. Elevated secretion of MCP-1, IL-6, and IL-8 due to S100A8 was inhibited by the TLR4 inhibitor TLR4i, the PI3K inhibitor LY294002, the $PKC{\delta}$ inhibitor rottlerin, the ERK inhibitor PD98059, the p38 MAPK inhibitor SB202190, the JNK inhibitor SP600125, and the NF-${\kappa}B$ inhibitor BAY-11-7085. S100A8 induced phosphorylation of ERK, p38 MAPK, and JNK in a time-dependent manner, and activation was suppressed by TLR4i, LY294002, and rottlerin. S100A8 induced NF-${\kappa}B$ activation by $I{\kappa}-B{\alpha}$ degradation, and NF-${\kappa}B$ activity was suppressed by PD98059, SB202190, and SP600125. These results indicate that S100A8 induces cytokine release via TLR4. Study of PI3K, $PKC{\delta}$, MAPKs, and NF-${\kappa}B$ will contribute to elucidation of the S100A8-invovled mechanism.

• Mycobiology
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• v.36 no.2
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• pp.102-105
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• 2008

The acetylcholinesterase (AChE) inhibitor of Yarrowia lipolytica S-3 was maximally produced when it was incubated at $30^{\circ}C$ for 36 h in an optimal medium containing 1% yeast extract, 2% peptone and 2% glucose, with an initial pH 6.0. The final AChE inhibitory activity under these conditions was an $IC_{50}$ value of 64mg/ml. After partial purification of the AChE inhibitor by means of systematic solvent extraction, the final $IC_{50}$ value of the partially purified AChE inhibitor was 0.75 mg/ml. We prepared a test product by using the partially purified AChE inhibitor and then determined its stability for the development of a new antidementia commercial product. The test product was stable at room temperature for 15 weeks.