• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.3
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• pp.68-76
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• 1999

Coprinus cinereus 2249 producing alkaline-active cellulase was screened from 29 species of Corpinaceae and constitutively produced alkaline carboxymethyl cellulase (CMCase) and filter paper cellulase (Fpase). When cultivated at pH 9.0, 25$^{\circ}C$ and 5 days, copnnus cinereus 2249 produced higher alkaline activity on 0.5% CMC, 2% wheat bran as carbon source and 0.5% peptone, 0.05% yeast extract as nitrongen source compared with other culture conditions. The level of cellulase production was higher in the presence of wheat bran than in the presence of CMC. The optimum temperature and pH for alkaline -active cellulase activity weas 50$^{\circ}C$ and 9, 0, respectively.

• Journal of the Korean Wood Science and Technology
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• v.48 no.6
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• pp.861-868
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• 2020

The use of polyphenol extracts from radiata pine (Pinus radiata) bark as raw materials for bio-foams was investigated along with the optimal NaOH extraction conditions. The targeted yield of alkaline extracts was 60%, and the targeted pH was 11 to 12. The radiata pine bark was composed of 70% of a 1% NaOH extract, which contained mainly polyphenols, such as proanthocyanidin (PA). As the particle size of the bark decreased, the yield of the 1% NaOH extracts increased from 57 to 87%. A range of NaOH concentrations, liquor ratios, and extraction times were explored to establish an economic polyphenol extraction method. More than 60% of the alkaline extract was extracted, and the pH of the extract was approximately 12 when the optimum extraction conditions were employed, i.e., a liquor to bark ratio of 5:1, a NaOH dosage of 17 to 18% based on the bark weight, and a 1 h extraction time. Following neutralization of the alkaline extract, structural analysis indicated severe structural changes in the PA during the alkaline extraction. Because the alkaline extract was barely soluble in the solvent used for the structural analyses, it is assumed that chemical modification is required to increase the solubility of the alkaline extract for the production of bio-foams.

• The Korean Journal of Zoology
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• v.25 no.2
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• pp.71-80
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• 1982

Some properties of alkaline phosphatase, partially purified from the liver of the local Pekin duck, Anas platyrhynchos, were investigated with the following results. 1. Gel-filtration of the duck liver extract indicated the presence of two molecular-weight species of alkaline phosphatase. 2. Electrophoresis of both enzyme preparations suggests the presence of two molecular forms of alkaline phosphatase with different physicochemical characteristics. 3. The liver alkaline phosphatase has an optimum pH of 9.0, and is further activated by $Mg^2+$ but not by $Ca^2+$. 4. The enzyme was relatively heat-labile, and was competitively inhibited by phosphate ions, but uncompetitively inhibited by L-phenylalanine. 5. These results are discussed in comparison with the properties of human and other animal alkaline phosphatases.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.8
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• pp.1043-1047
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• 2007

The physicochemical characteristics of green tea prepared by four kinds of alkaline ionized water (AIW; pH 8.57, 8.85, 9.23, and 10.06, respectively) were evaluated. Green tea was made by soaking commercial green tea leaves in AIW at $75^{\circ}C$ for 10 min (1.0 g/100 mL). Total phenol contents, total flavonol contents, and ascorbic acid contents of green tea decreased with increasing pH of AIW. Increasing pH of AIW tended to decrease lightness (L) and redness (a) of green tea but increase yellowness (b) in Hunter color values. The amount of epicatechins and radical scavenging activity of green tea also decreased with increasing pH of AIW, while caffeine was not significantly affected. Tyrosinase inhibition activity was the highest in AIW of pH 8.85.

• Applied Biological Chemistry
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• v.15 no.1
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• pp.27-33
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• 1972

The alkaline protease was isolated from the culture material of monascus sp. on wheat bran culture. The crude purification of this enzyme was extracted with distilled water and precipitated with ammonium sulfate of 0.5 saturation. And, the activity of this enzyme was determind very strongly by folin's colorimetric method. The optimal pH of this enzyme was ranging from pH 10 to 13 and the optimal temperature was $50^{\circ}C$. The pH stability was ranging from pH 5 to 12 and the enzyme activity was not inactivated by heat treatment in lower temperature than $40^{\circ}C$. The enzyme was protected from heat denature by the treatment of $Pb^#$, $Ba^#$, $Co^#$, $Zn^#$, and $Cu^#$, but was inactivated with $Hg^#$, $Fe^#$ strongly. Moreover, one of these metal ions, the cupper ion, has a strong protective activity on enzyme heat denature. And, it was not effected by treatment of EDTA.

• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.25-30
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• 1991

Chicken liver was enzymatically hydrolyzed with an alkaline protease and determined the optimal conditions of reaction temperature and time, pH and enzyme to substrate ratio(E/S ratio) for possible utilization as a protein supplementary ingredient. The functional properties of hydolysate measured were water and oil absorption capacity, emulsifying activity and viscosity and sensory properties were also evaluated. It was found that hydrolysis at $60^{\circ}C$ and pH 8.0 were most effective and the degree of hydrolysis increased with increasing E/S ratio. A decrease in water and oil absorption capacity and an increase in viscosity were found during hydrolysis. The lowest emulsifying activity and highest water absorption were measured for 1/2 hour-hydrolysate and little difference was found for those treated more than 1 hour. The sensory characteristics of odor showed no significant difference among the chicken liver hydrolysates while the brightness increased and red decreased significantly(p<0.01) as the hydrolysis proceeded.

• YAKHAK HOEJI
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• v.34 no.1
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• pp.47-53
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• 1990

Alkalophilic bacteria isolated from compost were selected, identified and tested for production of alkaline protease. The bacterium was tentatively assigned to Bacillus sp. based on the morphological, cultural and biochemical characteristics. The optimum pH of growth was 10 Galactose and Sodium glutamate enhanced the production of alkaline protease. The protease was most active at pH 11.0 and $60^{\circ}C$ and stable in the range of pH 5-11 and temp. $30^{\circ}-55^{\circ}C$. The protease was stabilized by the presence of calcium salts.

• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.349-354
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• 1991

An alkaline amylase-producing Bacillus sp. GM8901 was isolated and some properties of crude enzyme extract were examined. The microbiological and biochemical characteristics of GM8901 were very similar to those of B. licheniformis. The optimal temperature and pH for the cell growth and amylase production were $50^{\circ}C$ and pH 10.5. The crude amylase extract showed that the optimal temperature and pH were $50{\sim}60^{\circ}C\;and\;pH\;10{\sim}12$, respectively, and that the activity of amylase was stable up to $50^{\circ}C$ and in the range of $pH\;3{\sim}12$.

• Journal of Microbiology and Biotechnology
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• v.25 no.5
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• pp.662-671
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• 2015

To enrich the genetic resource of microbial xylanases with high activity and stability under alkaline conditions, a xylanase gene (xynSL4) was cloned from Planococcus sp. SL4, an alkaline xylanase-producing strain isolated from the sediment of soda lake Dabusu. Deduced XynSL4 consists of a putative signal peptide of 29 residues and a catalytic domain (30-380 residues) of glycosyl hydrolase family 10, and shares the highest identity of 77% with a hypothetical protein from Planomicrobium glaciei CHR43. Phylogenetic analysis indicated that deduced XynSL4 is closely related with thermophilic and alkaline xylanases from Geobacillus and Bacillus species. The gene xynSL4 was expressed heterologously in Escherichia coli and the recombinant enzyme showed some superior properties. Purified recombinant XynSL4 (rXynSL4) was highly active and stable over the neutral and alkaline pH range from 6 to 11, with maximum activity at pH 7 and more than 60% activity at pH 11. It had an apparent temperature optimum of 70℃ and retained stable at this temperature in the presence of substrate. rXynSL4 was highly halotolerant, retaining more than 55% activity with 0.25-3.0 M NaCl and was stable at the concentration of NaCl up to 4M. The enzyme activity was significantly enhanced by β-mercaptoethanol and Ca²⁺ but strongly inhibited by heavy-metal ions and SDS. This thermophilic and alkaline- and salt-tolerant enzyme has great potential for basic research and industrial applications.

• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.545-551
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• 1989

Thermostable alkaline protease of alkalophilic Bacillus sp. No. 8-16 has been purified, and the properties of the enzyme investigated. The characteristic point of the organism used is especially good growth in alkaline and thermal condition. The alkaline protease of the strain No. 8-16 was purified from crude enzyme by acetone precipitation, CM-cellulose ion exchange chromatography, Sephadex G-100 and Sephadex G-75 gel filtration. Through the series of chromatograpies, the enzyme was purified to homogeneity with specific activity of 37 fold higher than that of the crude broth. Characteristics of the purified enzyme were as follow; $K_m$ value for the enzyme was 1.3 mg/ml, the alkaline protease showed a maximal activity at 7$0^{\circ}C$ and from the pH 6.0 through 12.0, and stable for 1 hr. at 6$0^{\circ}C$. The moleclar weight of the enzyme was estimated to be 33,000 by Sephadex G-100 gel filtration. The activity of the alkaline protease was inhibited by iodoacetic acid and Ag$^+$, Hg$^+$, PMSF (phenylmethylsulfonyl fluoride), and activated by $Ca^{2+}$ and Mn$^{2+}$.