• Applied Biological Chemistry
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• v.38 no.2
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• pp.106-110
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• 1995

An alkaline protease-producing bacterium was isolated from Korean hot pepper paste and identified as Alteromonas sp. CN301. A alkaline protease was purified and characterized. The optimal pH and temperature for the enzyme activity were pH 12.0 and $35^{\circ}C$, respectively. Molecular weight of the enzyme was determined as 31,000 dalton by the SDS-PAGE. The enzyme was stable in the range of $pH\;6.0{\sim}13.0$ showing the residual activity above 80% of the enzyme activity. The residual activity of the enzyme was 64% when the enzyme was incubated at $50^{\circ}C$ for 1 hr. The activity of the enzyme was not affected by most metal ions tested except $Hg^{2+}$, and activated by Triton X-100, Tween 20 and Tween 80. The enzyme activity was severely inhibited by PMSF and EDTA, suggesting that the enzyme is serine protease having metal ion in its structure.

• Applied Biological Chemistry
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• v.33 no.2
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• pp.154-160
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• 1990

A bacterial strain which was capable of producing extracellular soymilk-clotting enzyme was isolated from soil samples during the course of screening test. The characteristics of the isolated strain K-324-7, indicated that the strain belonged to species of Bacillus cereus. The crude purification of this enzyme was precipitated by salting out with ammonium sulfate of 0.8 saturation. The optimal pH for the enzyme activity was at $6.1{\sim}7.0$ and below $50^{\circ}C$. The optimal culture medium for the production of soymilk-clotting enzyme were consisted of 0.2% glucose, 0.2% peptone, and 0.5% $KH_2PO_4$ with initial pH value of 6.5. The activity of enzyme was maximum when the microbe was cultured for 3 days at $35^{\circ}C$.

• Applied Biological Chemistry
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• v.38 no.5
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• pp.414-421
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• 1995

In order to establish informations important to the measurement of lipoxygenase (LOX) activity, providing conditions most favorable for its action and determining factors that inhibit activity, the influence of extraction buffer, substrate, pH, storage, temperature, NaCl, $CaCl_2$, other cations and antioxidants on LOX activity, and localization of LOX in cucumber tissues were carried out. The most favored substrate for LOX was linolenic acid followed by linoleic and arachidonic acids. LOX activity in both peel and mesocarp tissue extracts was maximum at pH 5.5 and relatively stable at $40^{\circ}C\;and\;50^{\circ}C$ temperature. The condition of 0.2 M NaCl with pH 5.0 was observed to provide optimum LOX stability. The enzyme activity was reduced by addition of cations, $Mn^{2+},\;Cu^{2+}\;or\; Al^{3+}$, except $Ca^{2+}$ which stimulated activity of LOX. Butylated hydroxy anisole (BHA) and propyl gallate decreased LOX activity with increasing concentration. Cucumber peel had higher activity than other tissues, locule or mesocarp, of cucumber.

• Microbiology and Biotechnology Letters
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• v.29 no.2
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• pp.67-71
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• 2001

Isolation and Growth Characteristics of AIkalophilic Bacillus sp. for Removal of Anthraquinone Dye. Kim, Jeong-Mog. School of Environmental Information, Taekyeung College, Kyungsan, 712-850, Korea -Alkalophilic strain degrading and decolorizing anthraquinone dye, Remazol brilliant blue R was isolated from natural system and named as Bacillus sp. ARB!. The optimal temperature and pH of Bacillus sp. ARBI were 35°C and 9.0, respectively. The pH of culture media during the fermentation were changed from 10 and 10.5 of initial values to 9.3 and 9.4 after 40 hrs, respectively. Decolorization efficiency in aerobic shaking culture of Bacillus sp. ARBI was markedly higher than that in standing culture. At the optimal culture condition, decolorization efficiency by the Bacillus sp. ARBl was 93% after 32 hrs batch culture. In the case of batch culture using real dye processing wastewater, dye decolorization efficiency of Bacillus sp. ARBl was 78% after 40 hrs.

• Applied Biological Chemistry
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• v.35 no.5
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• pp.339-345
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• 1992

In order to enhance the processing quality and utility of alaska-pollack meat, the optimum conditions for the preparation of pronase hydrolysate and the synthesis of plastein were investigated. The optimum temperature and pH for the hydrolysis of alaska-pollack by pronase were $40^{\circ}C$ and pH 7.0. The reaction time and enzyme concentration were 4 hr and 1,000 units per g of substrate. Under the above optimum conditions alaska-pollack was hydrolyzed by pronase yielding a hydrolytic degree of about 89%. Pronase hydrolysate was employed as substrate for plastein synthesis. The 30% pronase hydrolysates were adjusted to pH 7 for fruit-bromelain and pH 5 for stem-bromelain, and then plastein were synthesized by 1% bromelain at $40^{\circ}C$ for 24 hr. The plasteins synthesized by fruit- and stem-bromelain were consisted of peptides having average peptide length of 22.6 and 20.8 under the optimum synthetic conditions. The plastein synthesis reaction reduced considerably the bitterness of pronase hydrolysate.

• Microbiology and Biotechnology Letters
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• v.18 no.1
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• pp.26-30
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• 1990

Candida dattila K109 and K112 isolated from grapes in Korea showed killer activity toward Saccharomyces cereuisiae 5 x 47, S. cereuisiae 1368, Hamenula, Torulopsis, Kluyueromyces, Debaryomyces, and Brettanomyces, and showed the most effective killer activity at 22-26$^{\circ}C$ and at pH 3.9-4.1. The killer actvity of both toxins were remarkably decreased at higher temperature than $25^{\circ}C$ and higher pH than pH 4.0. And the toxins were suggested to be glycoproteins inactivated by pronase E and pepsin. The killer activity was not cured by incubation at elevated temperature of 30-37"C, but cured by treatment with 0.0105-0.3 ppm cycloheximie.imie.

• Economic and Environmental Geology
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• v.34 no.3
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• pp.301-306
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• 2001

Column tests were conducted to investigate the optimal condition of surfactant solution pH that can affect the removal efficiency in surfactant-assisted remediation. Toluene and 1,2,4-trichlorobenzene were chosen as the model hydrophobic substances. Two Iowa soils, Fruitfield sand and Webster clay loam, were leached with solutions of 4%(v/v) sodium diphenyl oxide disulfonate (DOSL, trade name Dowfax 8390), or 4%(v/v) trideceth-19-carboxylic acid (TDCA, trade name Sandopan JA36), or 4% (v/v) octylphenoxypoly ethoxyethanol (OPEE, trade name Triton X100). The test results revealed that a maximum removal of toluene and 1,2,4-trichlorobenzene was obtained at pH 10 of surfactant solution, and maximum recoveries of added toluene (94%) or 1 ,2,4- trichlorobenzene (97 %) were obtained for DOSL surfactant solution in Fruitfield sandy soil column. Increased removal efficiency by pH control of both toluene and 1,2,4trichlorobenzene was 16% and 20% for DOSL with Fruitfild sandy soil, respectively. In addition, the maximum recoveries of added toluene or I ,2,4-trichlorobenzene were 89% and 93% for DOSL surfactant solution in Webster clay loam soil column. The maximum increase of toluene and 1,2,4-trichlorobenzene removal was 26% and 19% for DOSL with Webster clay loam soil, respectively. These experimental results indicate that maintaining a high pH surfactant solution in surfactant-assisted remediation is desirable for efficient removal of NAPLs from contminated soils.

• Applied Biological Chemistry
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• v.12
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• pp.33-41
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• 1969

1. Crude cellulase extracted from wheat bran media of Chaetomium globosum with pH 7.0 McIlvaine buffer was fractionated by precipitation with ammonium sulfate and by treatment with the cellulose powder, DEAE-Sephadex A-25 and Amberite XE-65 (IRC-50) column chromatography. 2. Consquently two cellulases C-1 and C-2 were obtained by cellulose column chromatography. Cellulose C-1 was a powerful CMC-saccharifying and CMC-liquefying activity but cellulose C-2 was stronger CMC-liquefying activity compared to CMC-saccharifying activity and cellulase C-2 had smaller protein than that of cellulose C-1. And cellulose C-2 was fractionated by DEAE-Sephadex A-25 column chromatography into cellulase C-1-1 and cellulose C-1-2. 3. It can be obtained, therefore, that cellulose produced Chaelomium globosum consisted, at least, of three cellulases C-2, C-1-1 and C-1-2. 4. Cellulose C-1-1 was homogenous in the ultraviolet and the ultracentrifuge pattern. And cellulose C-1-1 had enzyme for CMC-saccharifying activity. 5. The optimum pH for the enzyme activity of cellulose C-1-1 was 4.0 in any methods of meas urement reducing sugar and viscosity. The optimum temperature was $40^{\circ}C$ in any methods. 6. The pH stability of cellulase C-1-1 was within pH 5.0 to pH 6.0 at $40^{\circ}C$ and fairly stable in acidic solution. 7. The heat stability was below $50^{\circ}C$ at pH 4.0 and complete heat inactivation of this cellulase occurred at $70^{\circ}C$.

• Journal of Life Science
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• v.18 no.4
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• pp.556-564
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• 2008

Response surface methodology was used to monitor the optimization of fermentation conditions for red ginseng wine. A central composite design was applied to investigate the effects of independent variables, fermentation temperature ($X_1$), fermentation time ($X_2$) and initial pH ($X_3$) on dependent variables, physicochemical characteristics and effective ingredients. Alcohol and total sugar content were significantly affected both by fermentation temperature and time. Crude saponin content was greatly affected by fermentation time, and pH was significantly affected by initial pH. Fermentation time and initial pH had a greater effect on ginsenoside content than fermentation temperature. Ginsenoside content increased along with fermentation time and initial pH. We elicited a regression formula for each variable, and superimposed the total optimum points of fermentation conditions for physicochemical characteristics and the effective constituents. The predicted values at the optimum fermentation conditions were at $21{\sim}27^{\circ}C$ for $15{\sim}20$ day in initial pH $4.6{\sim}5.2$.

• Microbiology and Biotechnology Letters
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• v.38 no.3
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• pp.273-277
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• 2010

Undecylprodiginine and streptorubin B are red-pigmented antibiotics produced by Streptomyces coelicolor A3(2). In this study, we investigated the correlation between productivity of these red-pigmented antibiotics and stress of pH shock. Biosynthesis of these red-pigmented antibiotics is enhanced at acidic pH shock on solid R2YE medium. The optimal pH shock is pH 4 which led to 1.6 fold and two-fold increase in the production of undecylprodiginine and streptorubin B as compared with control, respectively. In addition, the extract of pH 4 shocked cells exhibited a remarkable activity against Trichophyton mentagrophytes. However, neutral and basic pH shock did not give raise to promote a production of these red-pigmented antibiotics as well as antifungal activity. Thus, although the acidic pH shock is simple and easy method, it should be extremely effective approach to enhance a productivity of these red-pigmented antibiotics and other secondary metabolites.