• Microbiology and Biotechnology Letters
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• v.27 no.5
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• pp.404-409
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• 1999

The most favorable nitrogen source for the production of protease by Aspergillus oryzae PF was 2% soybean flour among sodium nitrate, ammonium sulfate, defatted soybean, skim milk, casein, peptone, and yeast extract. The production of protease from A. oryzae PF was higher at the concentration of 2% lactose than at variable concentration of glucose, sucrose, soluble starch, corn starch, potato starch, wheat starch, rice starch, cellulose, and gum arabic. Protease production was affected by the concentration of KH2PO4, Triton X-100, CaCo3, and MgSO4, and it was the highest at the highest at the concentration of 3% KH2PO4, 0.01% Triton X-100, 0.3% CaCO3, and 0.06% MGSO4.

• Korean Journal of Microbiology
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• v.28 no.3
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• pp.264-267
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• 1990

The objectives of the current studies were to establish the optimal conditions for the production of extracellular protease inhibitor in a strain of Streptomyces fradiae. As results, it was found that cell specific growth rate was very critical for the production of protease inhibitor and the optimum specific growth rate was found to be 0.05 h$^{-1}$ . Dissolved oxygen tension and pH were also important to regulate the inhibitor production. The inhibitory mode of the purified inhibitor to .alpha.-chymotrypsin was found to be competitive (K$_{i}$=5.5*10$^{-7}$ M). One mole of inhibitor could bind two moles of .alpha.-chymotrypsin and the complex has very low dissociation constant.t.

• Korean Journal of Food Science and Technology
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• v.13 no.3
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• pp.241-246
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• 1981

A fungal strain which produced high levels of acid protease and amylase was isolated from the atmosphere for application to the manufacture of digestive enzme preparation. This study was carried out to elucidate its microbiological characteristics, environmental conditions for production of the enzymes, and relationships between the enzyme activity and acidity. 1. The isolate was identified as a fungal strain which belonged to Aspergillus niger by the manual of Rafer and Fennel, and was found to be a strain producing high levels of acid protease and amylase. 2. The optimal pH of tile enzymes produced by the strain were: protease, 2.0;, ${\alpha}-amylase$, 4 to 5; and glucoamylase, 3 to 5. 3. The optimal culture conditions for production of the enzymes were: protease (at pH 2.5), 2 to 3 days incubation on wheat bran at $30^{\circ}C$; ${\alpha}-amylase$ and glucoamylase(at pH 3.0), 3 days incubation at $30^{\circ}C$. 4. The production of acid protease and glucoamylase was increased approximately by 20 percent when 2 percent of corn starch was added to the wheat bran medium. 5. The addition of 0.3 percent ammonium sulfate to the wheat bran medium resulted in enhancing the enzyme production, especially of acid prctease.

• The Korean Journal of Food And Nutrition
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• v.23 no.3
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• pp.399-404
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• 2010

This study was conducted to determine the influence of culture conditions such as temperature, time, water content, koji-thickness, and agitation on the production of protease by Rhizopus sp. ZB9, isolated from Korean Nuruk, during the preparation of rice koji, which is used in brewing the Korean rice wines, Takju and Yakju. Rice koji was made under different culture conditions, and the proteolytic activity of each koji was tested. The temperature range suitable for the production of protease was $28~32^{\circ}C$. Based on the protease and color, 60 hours of cultivation at $28^{\circ}C$ was shown to produce optimum results. The production of protease increased in proportion to the increase in water content of steamed rice from 25% to 35%. An increase in koji-thickness induced no adverse effects on the production of protease, and agitation during cultivation showed beneficial effects.

• The Korean Journal of Mycology
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• v.24 no.2 s.77
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• pp.149-154
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• 1996

Effects of various kinds of sawdusts, supplements and culture conditions on activities of several enzymes such as protease, phenoloxidase and cellulase produced from mycelium of P. ostreatus grown on sawdust medium were studied and the results are as follows; Higher specific activity of these enzymes was observed when oak tree sawdust and poplar tree sawdust were supplemented with rice bran or wheat bran at rate of 30%, 20% and 10% in total volume respectively. Higher total activities of protease, phenoloxidase and cellulase were observed at 70% of the moisture contents of culture media, while lower activity of these enzymes was observed with 40% moisture contents of sawdust culture medium. The pH 4 and 9 of the sawdust media appeared to be optimum pH for the. production of protease while pH 5 and 7 were optimal for the production of phenoloxidase. The pH 6 of the sawdust medium was optimal for the production of cellulase. The optimum incubating temperature for the production of protease, phenoloxidase and cellulase was $25^{\circ}C$. Higher total activities of protease and phenoloxidase were observed when culture medium was added with wood vinegar at the control, and 0.5% for cellulase.

• Microbiology and Biotechnology Letters
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• v.34 no.4
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• pp.323-328
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• 2006

A bacterium producing the extracellular protease was isolated from insect-eating plant and has been identified as a member of the genus Bacillus based on partial 165 rRNA sequences. In order to develop the medium composition, effects of ingredients including nitrogen sources, carbon source, metal ions and phosphate were examined for protease production of the isolate, SH-8. Soluble starch increased the protease productivity, while glucose repressed it. Yeast extract was effective nitrogen source for enzyme production, but the pretense production of Bacillus sp. SH-8 was reduced by large amount of yeast extract. The calcium was found to induce pretense activity as well as protease productivity. However, cell growth and enzyme production was completely inhibited by divalent ions such as $Zn^{2+}$, $Cu^{2+}$, $Co^{2+}$ and $Mn^{2+}$. The maximum protease productivity was reached 435 unit/ml in the optimized medium consisting of soluble starch (2%), yeast extract (0.3%), $CaCl_2$ (0.3%), $K_2HPO_4$ (0.01%) and $KH_2PO_4$ (0.01%). The pretense activity of culture filtrate was dramatically decreased after incubation for 26 h.

• Microbiology and Biotechnology Letters
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• v.22 no.5
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• pp.515-521
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• 1994

A bacterial strain, which showed the high protease activity at low temperature and the high tolerance for the surfactant, was isolated from soil and identified as Xanthomonas sp. YL-37. The optimal temperature, initial pH, and cultivation time for the production of the alkaline protease by Xanthomonas sp. YL-37 were 20$\circC , 11.0, and 84 hours, respectively. In the jar fermenter culture of Xanthomonas sp. YL-37, the alkaline protease activity was about 15,000 DU/ml/-broth after cultivating for 108 hours. The optimal pH and temperature for the protease activity were 70$\circC and 11.0, respectively. The protease was relatively stable at the pH range of 7.0~12.0 and at the temperatures below 50$\circC . The protease activity at 20$\circC was about the level of 40% of its activity at 70$\circC . The enzyme was suggested as a serine protease because the enzyme activity was inhibited by phenylmethane sulfonyl fluoride, a serine modifier.

• Journal of Microbiology and Biotechnology
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• v.11 no.4
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• pp.558-563
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• 2001

A new alkalophilic strain of Bacillus pumilus JB¬05 producing bleach-stable and halo-tolerant alkaline protease was isolated from cement industry effluents in Karnataka, India. The effects of carbon and nitrogen sources on protease production by this alkalophilic strain were observed after a 30-h incubation. A high level of alkaline protease activity was obtained in the presence of starch as the carbon and peptone as the nitrogen sources. The partially purified enzyme showed an optimum temperature and pH activity at $58^{\circ}C$ and 10.5, respectively. The enzyme was completely inhibited by PMSF (95.0%) indicating it as a serine protease. It is bleach-stable as it retained 35% original activity in the presence of 10% (v/v) hydrogen peroxide at $30^{\circ}$C after 2 h and is halo-tolerant as it retained 70% original activity in the presence of 2.5 M sodium chloride at $30^{\circ}C$ after 2 h incubation.

• Journal of Life Science
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• v.9 no.4
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• pp.348-357
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• 1999

Seventy-two strains of Pseudomonas aeruginosa isolated from the patients were tested for pigment production, exoenzyme production and antimicrobial susceptibility. In the pigment production test, 23.6% of total 72 strains produced both pyocyanine and pyoverdin. Pyoverdin and pyomelanin producing strains were in 9.7%, and 5.5% produced pyoverdin and pyorubin. Strains producing of all of exoenzyme, protease, elastase and lecithinase were in 5.6%. The most common type of exoenzyme production was both protease and elastase producing. Protease producing strain were 23.6%, Among the 72 strains, 50% produced protease. As the result of antimicrobial susceptibility in the isolated 20 strain, most strain were resistant to sulfamethoxazole(90%), but sensitive to other tested antibiotics more than 60%. The MIC50 and MIC90 level of tested antibiotics to 70 strains were 128 $\mu\textrm{g}$/$m\ell$, 512 $\mu\textrm{g}$/$m\ell$ for KM, 8,256 $\mu\textrm{g}$/$m\ell$ for GM, 8, 128 $\mu\textrm{g}$/$m\ell$ for CPZ, and 8, 64 $\mu\textrm{g}$/$m\ell$ for PIPC respectively.

• Journal of Applied Biological Chemistry
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• v.49 no.4
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• pp.135-139
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• 2006

A alkalophilic strain, Bacillus licheniformis MH31 producing an alkaline protease was isolated from mine soil of Boryeong in Korea. Production of a high level of alkaline protease was achieved 42 h after incubation when the bacterium was grown at pH 9.0 and $35^{\circ}C$ in Horikoshi medium supplemented with 0.5%(w/v) starch and 1%(w/v) skim milk as carbon and nitrogen source, respectively. The molecular weight of partially purified enzyme was estimated to be 30 kDa by SDS-PAGE and its optimum pH was pH 10. The enzyme showed optimum temperature at $50^{\circ}C$, and was stable up to $60^{\circ}C$ after 1 h incubation. The protease was strongly inhibited by 1 mM of PMSF which was known well as strong inhibitor of serine proteases, but almost not inhibited by 5 mM of EDTA and 1,10-phenanthroline. When the protein hydrolysis products of 1% skim milk by partially purified protease was compared with available commercial proteases using HPLC analysis, most of hydrolysis products were detected below molecular weight of 10,000 and the hydrolysis ratio of purified enzyme was 24.8% lower than those(above 32%) of commercial proteases.