• Microbiology and Biotechnology Letters
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• v.23 no.5
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• pp.602-608
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• 1995

The aim of the present research program was to construct an optimum fermentation system and to characterize the properties of cathepsin B inhibitor from Streptomyces chromofuscus SMF28. Glucose and casitone were proved to be good carbon source and nitrogen source, respectively. The production of inhibitor was high at lower concentration than 10 mM of inorganic phosphate. The optimum temperature and pH for the production of inhibitor were 30$\circ$C and pH 7, respectively. The production of inhibitor was related to mycelial growth and was affected by medium composition. The inhibitor in culture filtrate of S. chromofuscus SMF28 was purified by butanol extraction, silica gel chromatography, Amberlite IRC-50 (H$^{+}$ form) chromatography, preparative TLC, and preparative HPLC. From amino acid analysis and UV, IR, $^{1}$H-NMR spectroscopic analysis, the inhibitor was identified as a peptide containing valine and phenylalanine derivative.

• Journal of Microbiology and Biotechnology
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• v.1 no.4
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• pp.288-292
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• 1991

The aim of the current study is to evaluate the effects of medium compositions on the production of protease inhibitor in Streptomyces sp. SMF13. The production of protease inhibitor was counter-currently linked to extra-cellular protease, which were regulated by the culture conditions. Nitrogen source was the most critical ingredient affecting the production of protease inhibitor and protease. Carbon source was an important factor to determine the culture pH which affected very clearly the formation of protease and protease inhibitor. Inorganic phosphate inhibited the protease inhibitor production which was linked to the cell growth rate, although the optimal conditions for the production of protease inhibitor were not favouring to the cell growth.

• Journal of Life Science
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• v.6 no.2
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• pp.120-128
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• 1996

In the screening of actinomycetes culture filtrate for inhibitor of adenosine deaminase, a novel inhibitor was found in a cultured broth of strain J-144K. The optimum conditions for the adenosine deaminase inhibitor production from the isolated strain J-144K were evaluated. This strain showed the maximum yield of adenosine deaminase inhibitor when grown at pH 7.0 and 30$\circ$C for 60 hours in the medium of 1.0% dextrose, 0.5% yeast extract, 0.5% peptone and 0.1% KH$_{2}$PO$_{4}$ under the aerobic condition. Through the activated charcoal extraction, methanol fractionation, Dowex 50 H$^{+}$ X-8 ion exchange column chromatography, Dowex CI$^{-}$ X-8 ion exchange column chromatography, and Sephadex G-15 gel filtration procedures, this inhibitor was purified with three materials.

• YAKHAK HOEJI
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• v.39 no.3
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• pp.306-313
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• 1995

The aim of the present study was to produce low molecular weight cathepsin B inhibitor. A strain of Streptomyces aburabiensis isolated from soil in Korea was selected and the optimum condition for the production of the inhibitor was evaluated. Glucose and soytone were selected as best carbon and nitrogen sources, respectively. From the kinetic analysis in batch fermentation, it was found that the specific cathepsin B inhibitor production rate (q$_{p}$) was linearly related to specific growh rate ($\mu$). The inhibitor in culture filtrate was purified by adsorption on activated charcoal, butanot extraction, silica gel chromatography, ion exchange chromatography using Dowex-1 (Cl form) and Amberlite IRC-50 (H$^{+}$ form), and preparative TLC. From the UV, IR, Mass spectroscopy and $^{1}$H-NMR, the inhibitor was thought to be a new inhibitor of which molecular weight was 199.

• Korean Journal of Food Science and Technology
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• v.18 no.5
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• pp.339-344
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• 1986

The specific reaction of trypsin inhibitors with trypsin to form stable complexes was successfully applied for detection of trypsin inhibitors in soybean. Soybean extract was treated with $Ca^{++}$ to remove globulin fraction, followed by digestion with trypsin and fractionated by chromatography on Sephadex G-50. The void volume fraction contained the trypsin-trypsin inhibitor complexes as well as trypsin. The trypsin inhibitors were then detected by their molecular weight differences on SDS-polyacrylamide gel electrophoresis, in which the complexes dissociate into trypsin and its inhibitors. With the method proposed, trypsin inhibitors were indentified by their ability forming the stable complexes with trypsin and their anti-tryptic moiety. The formation of the complexes with trypsin was further confirmed by two dimensional electrophoresis and DEAE-Sephadex A-25 chromatography. Employing the proposed method, it was found that soybean (Glycine max cv. Hill) contained 7 trypsin inhibitors.

• Journal of Microbiology and Biotechnology
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• v.24 no.5
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• pp.667-674
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• 2014

Twenty-five Saccharomyces cerevisiae strains were screened for the highest sugar tolerance, ethanol-tolerance, ethanol production, and inhibitor resistance, and S. cerevisiae KL5 was selected as the best strain. Inhibitor cocktail (100%) was composed of 75 mM formic acid, 75 mM acetic acid, 30 mM furfural, 30 mM hydroxymethyl furfural (HMF), and 2.7 mM vanillin. The cells of strain KL5 were treated with ${\gamma}$-irradiation, and among the survivals, KL5-G2 with improved inhibitor resistance and the highest ethanol yield in the presence of inhibitor cocktail was selected. The KL5-G2 strain was adapted to inhibitor cocktail by sequential transfer of cultures to a minimal YNB medium containing increasing concentrations of inhibitor cocktail. After 10 times of adaptation, most of the isolated colonies could grow in YNB with 80% inhibitor cocktail, whereas the parental KL5 strain could not grow at all. Among the various adapted strains, the best strain (KL5-G2-A9) producing the highest ethanol yield in the presence of inhibitor cocktail was selected. In a complex YP medium containing 60% inhibitor cocktail and 5% glucose, the theoretical yield and productivity (at 48 h) of KL5-G2-A9 were 81.3% and 0.304 g/l/h, respectively, whereas those of KL5 were 20.8% and 0.072 g/l/h, respectively. KL5-G2-A9 reduced the concentrations of HMF, furfural, and vanillin in the medium in much faster rates than KL5.

• Korean Journal of Microbiology
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• v.28 no.1
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• pp.65-70
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• 1990

The objective of the current study is to elucidate the biological roles of proteinase inhibitor in microorganisms. As the first step, a strain of Streptomyces fradiae was selected as a producer of extracellular proteinase inhibitor. The proteinase inhibitor was purified from culture broth through ultrafiltration, gel-filtration and ion-exchange chromatography. Molecular weight of the proteinase inhibitor was estimated to be 16, 800 by SDS polyacrylamide gel electrophoresis. It was found that the proteinase inhibitor inhibited only alkaline serine proteinases such as subtilisin, $\alpha$-chymotrypsin and Promase E but not trypsin and other proteinases. The mode of inhibition against Pronase E with succinyl-phenylalanine-p-nitroanilide as a substrate was competitive.

• Microbiology and Biotechnology Letters
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• v.28 no.6
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• pp.322-328
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• 2000

To screen agent for the treat-ment of Alzhimers Disease several strains of bacteria producing acetylcholinesterase inhibitor ware isolated from soil. Strain 960903 showed strong acetylcholinesteras inhibitory activity and low butyrylcholinesterse inhibitory activity. The strain 960903 was identified as Pseudomonas sp. Acetylcholinesterase inhibitor ws highly achieved in fermentation medium containing soluble starch 3.0%, glycerol 1.0%, pharmamedia 0.5%, KCI 0.3%, $CaCO_3$ 0.2%, MgS $O_4$..$7H_2$O 0.05%, $KH_2$$PO_4$ 0.05%(pH6.5) at $30^{\circ}C$ for 4 days. Acetylcholinesterase inhibitor was purified by Diaion WA-30($OH^{-}$) column charomatography and cellulose column chromatography. Acetylcholinesterase inhibi-tor showd the maximum wavelength at 205 nm and was soluble in water, acetic acid, ethanol, methanol and dime-thyl sulfoxide. The concentration of 50% inhibition($IC_{50}$) of inhibitor against acetylcholinesterase was 25$\mu\textrm{g}$/ml. The inhibitor was inactivated on heating ar $100^{\circ}C$ fro 15 min and more stable in acidic region than alkaline region.n.

• Journal of Microbiology and Biotechnology
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• v.18 no.6
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• pp.1115-1120
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• 2008

A novel cathepsin B inhibitor-producing bacterium was isolated from marine sediments and identified based on its 16S rDNA sequence as Pseudomonas sp. strain PB01 (Accession No. EU126129). The growth and enzyme inhibitor production were investigated under various culture conditions. A mixture of organic nitrogen source was required for the optimal production, whereas both glucose and maltose proved to be the effective carbon sources for cathepsin B inhibitor production. Other optimal culture conditions included temperature range between 25 and $28^{\circ}C$, initial medium pH of 6.6, and shaking speed of 200 rpm. Under these optimal conditions, the maximum inhibitory activity from culture broth was approximately 50% after 30 h of cultivation. Additionally, kinetic study revealed that inhibitor production paralleled with cell growth, which suggested that the inhibitor may be a primary metabolite of that bacterium.

• Microbiology and Biotechnology Letters
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• v.29 no.1
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• pp.25-30
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• 2001

A strain of Actinomycetes producing cathepis B inhibitor was isolated from soil and identified as Streptomyces misakiensis. The product of S. misakiensis inhibited effectively cathepsis B proteinases as well as trypsin and papain. The cathepsin B inhibitor were largely produced with incubation for 4 days. The S. misakiensis was the most growth with incubation for 5 days. The cathepsin B inhibitor was isolated from the extraction of both with ethanol, ethanol and chlorofrom, and following several column chromatography such as sephadex G-15, silica gel 60 and sephadex LH-20 chromatography. The moleculer weight of purfied inhibitor was 138 dalton.