• Applied Biological Chemistry
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• v.31 no.4
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• pp.356-360
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• 1988

The alkaline protease producing bacteria isolated from soil and identified as Bacillus subtilis. The optimum medium for alkaline protease production from the microorganism was as follows; soluble starch, 1.5% ; proteose peptone, 0.5% ; $K_2HPO_4$, 0.1% ; $MgSO_4{\cdot}7H_2O$, 0.02% and sodium carbonate, 1.0%. The optimum temperature for alkaline protease production was $35^{\circ}C$, and the initial pH of medium was pH 10.5. The alkaline protease activity was about 2,300 U per ml of culture broth by Casein-Folin Method. A 9.2 fold purification of alkaline protease was obtained from culture broth. The recovery was 14% and purified enzyme was identified as single band, and its molecular weight was about 19,000. The optimum temperature for enzyme reaction was $70^{\circ}C$, and optimum pH was 12. The activity of purified enzyme was inhibited by metal ion ($Fe^{++}$), and Phenylmethylsulfonyl Fluoride, a serine protease inhibitor.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.754-759
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• 2002

In order to develope a new pretense applicable to industries, a bacterium which produces a remarkable amount of extracellular pretense were isolated from soil. About 10 bacterial strains producing pretense were isolated from samples of soil, and strain PANH765 showed the highest activity of pretense production among them. The strain was identified as Bacillus subtilis according to the Bergey's Manual of Systematic Bacteriology based on its morphological, cultural and physiological characteristics. B. subtilis PANH765 showed the maximal production of pro-tease in the medium containing 2.0% glucose, 1.0% yeast extract, 0.2% ammonium nitrate, 0.02% ferrous sulfate and 0.02% dipotassium hydrogen phosphate. Under the optimal condition with temperature of 3$0^{\circ}C$, initial pH of 7.0 and shaking speed of 150 rpm, the pretense production reached a maximum level with 36 hr cultivation (6.34 U).

• Applied Biological Chemistry
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• v.41 no.5
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• pp.342-348
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• 1998

A bacteria producing protease against soy protein was isolated from various traditional Me-Ju, in order to improve utililization and characteritics of soy protein hydrolysates reduced bitterness and advanced flavors. The optimal culture conditions for protease production was investigated. The isolated bacteria was identified as Bacillus subtilis by morphological and physiological charateristics and named Bacillus subtilis YG-95. The optimal culture condition of liquid medium for protease production by Bacillus subtilis YG-95 composed of 3.5% soluble starch, 3.0% soy protein isolate, 0.25%, dextrose, 0.5% NaCl, 0.25% $K_2HPO_4$ with on initial pH of 7.6, for 60 hrs at $45^{\circ}C$.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.3
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• pp.186-191
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• 2005

In this study, a microorganism-produced protease was used to improve the quality of fabrics. First, the protease-producing bacteria were isolated from soils, and one of them was selected and identified as Bacillus sp. SJ-121. The optimal medium composition for its growth and protease production was determined to be as follows: glucose 1g/L, soybean meal 0.5g/L, soy peptone 0.5, $K_2HPO_4\;0.2,\;MgSO_4\cdot7H_2O\; 0.002,\;NaCl\;0.002,\;and\;Na_2CO_3g/L$. Also, the optimal temperature for the production of the protease by Bacillus sp. SJ-121 was about $40^{\circ}C$ at pH 7. The wool and silk were treated with the protease from Bacillus sp. SJ-121. Following the protease treatment, changes in the surface of a single yarn of the fabrics were observed by both an optical microscope and a scanning electron microscope (SEM). Changes in the K/S value of the wool and silk were measured by spectrophotometric analysis, in order to determine the amount of dye uptake in the fabrics. We also performed a tensile strength examination in order to determine the degree and nature of mechanical changes in single yarns of the wool and silk fabrics. By increasing the protease treatment time to 48 h, the dyeing characteristics of the fabrics were enhanced, and the surfaces of the single yarns of the fabrics became smoother, due to the removal of soil and scale in them. However, no mechanical changes were detected in the fabrics. Therefore, we suggest that proper treatment of the protease produced by Bacillus sp. can improve the quality of silk and wool.

• Microbiology and Biotechnology Letters
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• v.30 no.1
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• pp.26-32
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• 2002

For commercial production of Korean fermented anchovy sauce through rapid fermentation, a bacterial strain which showed the high protease activity was isolated from a commercially fermented anchovy sauce. The isolate was Bacillus amyloliquefaciens, and named as B. amyloliquefaciens HTP-8. The incubation temperature, initial pH, and cultivation time for optimal production of protease by B. amyloliquefaciens HTP-8 were $30^{\circ}C$, 7.0, and 3 days, respectively. In jar fermenter, B. amyloliquefaciens HTP-8 showed higher protease activity when grown at pH 7.0. The protease was partially purified by 80% ammonium sulfate precipitation and CM-Sephadex C-50 ion exchange chromatography. The partially purified enzyme had specific activity of 103.3 units/mg, yield of 0.4%, and purification fold of 43.0. The optimal pH and temperature for the protease activity were 10.0 and $50^{\circ}C$, respectively. The protease was relatively stable at the pH range of 7.0~12.0 and at the temperatures below 4$0^{\circ}C$. The activity of the enzyme was inhibited by $Ag^{＋}$ /, $Ba^{2＋}$ and selectively inhibited by PMSF, suggesting that it is a serine protease.

• Korean Journal of Microbiology
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• v.48 no.1
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• pp.48-51
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• 2012

A novel Chryseobacterium sp. JK1 strain producing extracellular protease had been isolated from soil. The largest clear zones were observed on nutrient agar plates supplemented with 1% skim milk at $30-35^{\circ}C$ along with the growth of Chryseobacterium sp. JK1. The cell growth of JK1 strain was maximal at 24 h and maximum protease activity was reached up to 560 unit/ml at the stationary phase in liquid culture. In the presence of maltose, glucose or mannitol in Nutrient broth, cells grew well, but protease were produced poorly with lower production yields of 64-77% than in NB broth only. Similarly, the addition of skim milk, beef extract, yeast extract, malt extract or tryptone showed good growth and poor enzyme production. On the contrary, the addition of $(NH_4)_2HPO_4$ or $(NH_4)_2SO_4$ gave poor growth and good enzyme production of 121-146%.

• Applied Biological Chemistry
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• v.39 no.6
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• pp.449-454
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• 1996

We investigated the optimal condition for the production of extracellular pretense(a cuticle-degrading pretense) from entomopathogenic fungus Beauveria bassiana(ATCC7159) in liquid medium by adding of gelatin, bovine serum albumin(BSA), casein and polypeptone. The optimal induction medium for production of extracellular pretenses is composed of 0.5% polypeptone, trace elements and 50 mM potassium phosphate(pH 6.0). In this condition, the production of extracellular pretenses increased rapidly after the 24hrs, peaking at the third day and there was little inductive effect in culture broth more than pH 7.0. The pretenses were inhibited by phenyl methyl sulfonyl fluoride(PMSF). High activity of pretense was showed both range of pH 8.5 and 11.5 and also detected by three different portions of slice gel derived from non-denaturing isoelectricfocusing gel. At least three different extracellular pretenses are produced in optimal production medium when polypeptone is used as the sole carbon and nitrogen source.

• Applied Biological Chemistry
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• v.33 no.3
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• pp.247-251
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• 1990

A bacterial strain which produce a high level of protease was isolated from a commercial salted fish, squid jetkal. This strain was identified as a strain belong to the genus Halobacterium and was found to be extremely halophilic : more than 2.0M of sodium chloride was required for the growth. The protease production by the strain was maximized when grown on Norberg & Hofsten medium containing 4.5M sodium chloride, 1.5% gelatin and 0.4% yeast extract (initial pH 7.0) for 108hrs at $38^{\circ}C$.

• Applied Biological Chemistry
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• v.19 no.4
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• pp.227-232
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• 1976

This experiment was carried out to investigate the effects of red pepper powder on its enzyme production and growth of Aspergillus oryzae. In this report, Aspergillus oryzae A and G strains were cultured to the wheat bran and Czap다 Dox liquid media containing red pepper powder. And their enzyme activity. dry mycelial weight, pH and acidity were determined respectively. The results obtained were as follows. 1. In the case of protease reaction on the substrate without salt, the addition of red pepper powder ranging from 0.05 to 30 per cent to the wheat bran medium showed the increased neutral and alkali protease production in comparison with the control. However, the acid protease production were decreased by the addition of red pepper powder in the case of Aspergillus oryzae G strain. 2. In the case of protease reaction on the substrate with 10 per cent of salt, wheat bran medium containing 0.05 to 10per cent of red pepper powder showed the high protease production in comparison with the control. 5. As the amount of red pepper added to the Czapek-Dox lipuid culture was increased, the dry mycelial weight produced by Aspergillus oryzae A and G strains were also increased. And the dry mycelial weight produced by Aspergillus oryzae A strain was much more than that of Aspergillus oryzae G strain. 6. The addition of red pepper powder brought the fall of pH in Czapek-Dox liquid medium. 7. By the increase of red pepper powder concentration, the acidity in Czapek-Dox liquid culture were increased. And the increase ratio in the case of Aspergillus oryzae G strain was more remarkable than that of Aspergillus oryzae A strain.