• Microbiology and Biotechnology Letters
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• v.6 no.1
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• pp.33-40
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• 1978

Immobilization of alkaline protease was investigated by absorbing the enzyme on adsorbents. Alkaline protease was adsorbed on silica gel selected as a carrier to immobilize the enzyme. In this study, properties of the immobilized enzyme were compared with those of the soluble enzyme. 1) The optimum pH (10.0) of the enzyme was not changed, but the activity was increased at alkaline pH by immobilization. 2) The optimum temperature of the immobilized enzyme was shifted from 50$^{\circ}C$ to 45$^{\circ}C$, while the temperature-activity Profile became broader than those of the soluble enzyme. 3) The pH stability of the immobilized enzyme was significantely increased at pH 4.0, althouth it did not change in the neutral and alkaline pH region. 4) The heat stability of the enzyme was enhanced in the temperature range of 55$^{\circ}C$∼65$^{\circ}C$ by the immobilization. 5) The immobilized enzyme retained 40％ of its original activity after repetitive use for 6 times. 6) The enzyme stability was greately improved for a prolonged storage at 4$^{\circ}C$.

• Food Science and Preservation
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• v.11 no.2
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• pp.227-232
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• 2004

• YAKHAK HOEJI
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• v.31 no.4
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• pp.236-251
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• 1987

The chemistry, antimicrobial properties, organic soil resistance, toxicity, corrosivity and chemical stability of stabilized alkaline 2%, glutaraldehyde solution(SGS) are discussed. SGS retains the maximum antimicrobial activity of alkaline glutaraldehyde solutions and the chemical stability here to fore observed only with acidic glutaraldehyde solutions. These improvements, along with the inherent resistance of glutaradehyde to neutralization by organic soil, allow SGS to be continuously used for 14 days in situations of high dilution, or 28 days in situations of low dilution.

• Transactions of the Korean hydrogen and new energy society
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• v.32 no.6
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• pp.524-533
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• 2021

In this study, a series of anion conductive organic/inorganic composite membranes with excellent ionic conductivity and chemical stability were prepared by introducing graphene oxide (GO) inorganic nanofiller into the quaternized poly(phenylen oxide (Q-PPO) polymer matrix. The fabricated organic/inorganic composite membranes showed higher ionic conductivity than the pristine membrane. In particular, Q-PPO/GO 0.7 showed the highest ionic conductivity value of 143.2 mS/cm at 90℃, which was 1.56 times higher than the pristine membrane Q-PPO (91.5 mS/cm). In addition, the organic/inorganic composite membrane showed superior dimensional stability and alkaline stability compared to the pristine membrane, and the physicochemical stability was improved as the content of inorganic fillers increased. Therefore, we suggest that the as-prepared organic/inorganic composite membranes are very promising materials for anion exchange membrane applications with high conductivity and alkaline stability.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.8
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• pp.129-135
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• 2016

This study is about ionic water generator filter Recently, a lot of people feel deep interest in health and drinking water. Evaluation of the stability of oxidation-reduced potential (ORP) using the filter of the alkaline water. This study utilizes the three filter of activated carbon, UF, carbon block in alkaline reduced water equipment. Passing the water to the filter is evaluated that the OPR values are stability in accordance with the change of the volume in the bucket. Alkaline reduced water equipment is a system that has the function of making the water reduction. This system is the values of the human body beneficial minerals and ORP are made in the functional water has a very low value than general water. Which has passed through the filter the water in the water negative ions and positive ions through the electrolytic. After electrolysis, the cathode side by water, including $Ca^+$, $K^+$, $Mg^+$, $Na^+$ water gets Alkaline Reduced Water containing the minerals beneficial to the human body. A positive electrode side is made of the organic materials that have an anion such as chlorine (Cl), phosphorus (P), sulfur(S). This experiment uses the Alkaline Reduced Water to adjust the magnitude of the voltage of the electrolysis in the Alkaline Reduced Water. That is 1st step(pH8) 2nd step (pH8.5) 3th step (pH9), 4th step (pH9.5) in the Alkaline Reduced Water and -1st step (pH6.0), -2nd step (pH5.0) used as the acidic oxidation water. When the water passes through the three filter in this system was evaluated whether the ORP values are changed and stabilized. When about 100 liters of water passing through the filter was confirmed that the ORP values are stability and evaluation.

• Textile Coloration and Finishing
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• v.31 no.4
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• pp.249-257
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• 2019

Baker's yeast(Saccharomyces cerevisiae) was used as a biocatalyst for eco-friendly indigo dyeing and the reducing power of yeast according to the alkaline solution type was compared. NaOH solution, lye, and buffer solution were used as alkaline solutions. The reducing power(K/S value, oxidation/reduction potential(ORP), pH) was monitored according to the elapsed time including the initiation of reduction, peak reduction, and the end of reduction. In all alkaline solutions, it was confirmed that yeast can be used reducing agent in indigo reduction dyeing. The pH stability and reducing power of buffer solution was better than that of NaOH alone. Although, pH and ORP stability of the reduction bath in lye were better than that of buffer solution, K/S value in buffer solution was higher compared to lye. The reducing power was different depending on the starting pH of the dye bath, and it was better when starting at pH 10.70 than at pH 11.30. Fastnesses to washing, rubbing, and light were relatively good with above rating 4. There was no significant difference in colorfastness depending on the type of alkaline solutions.

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.222-228
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• 2001

Vibrio metschnikovii strain RH530 is a non-pathogenic, industrially-important alkaline protease producer which has been isolated from wastewater. In this paper, we report on the transformation of this strain by using the method of electroporation. A field strength of $7.5\;kVcm^{-1}$ and $25\;{\mu}F$, and using a 0.2-cm cuvette, appeared to be the optimal conditions for electroporation of the cells with the recombinant pSBCm plasmid carrying the vapK alkaline protease gene and the ColE1 replicon. Cells were subjected to osmotic shock in order to remove extracelluar DNase, and adding 200 mM of sucrose to electroporation buffer cells showed an increased transformation efficiency. Maximum efficiency of transformation was obtained at an early exponential growth phase. Using all of the conditions mentioned above, we routinely obtained a transformation efficiency of more than $10^4{({\mu}g\;plasmid\;DNA)}^{-1}$. The stability of the plasmid pSBCm in V. metschnikovii RH530 was 25% after 18h of growth (27 generations) in the medium without antibiotic selection. The insertion of the par locus to the pSBCm increased the stability of the plasmid up to 42% without selective pressure. The increase in plasmid stability was accompanied by the increase in the productivity of alkaline protease in the recombinant V. metschnikovii strain RH530. Determining optimal conditions for the transformation of the industrially-important, nonpathogenic Vibrio strain, and the improvement of plasmid stability by introducing the par locus into the high copy number plasmid vector, will allow the development of procedures involved in the genetic manipulation of this strain, particularly for its use in the production of industrial enzymes such as alkaline protease.

• Journal of Food Hygiene and Safety
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• v.12 no.1
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• pp.15-19
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• 1997

The stability of monascin yellow pigment isolated from Monascus purpureus was determined over a period of storage for the wide range of pH, various metal ions and antioxidants. The absorption maximum of monascin pigment was 385 nm. Monascin pigment was more stable in acid solutions than in alkaline (pH 9 and pH 11) during storage period. It was also observed the reduction of absorption was occur after 3 days storage. The stability of monascin pigment was not changed by adding the various metal ions of the concentration of 10-4 M, however, it was unstable by adding the Zn2+, Al3+ and Fe3+ of 103- M concentration. The antioxidants. BHA, BHT, cysteine and L-ascorbic acid, have no effects on the stability of monascin yellow pigment. Thus, it may be concluded that the monascin pigment is stable and useful food additives as the natural colorant except for the alkaline food and food containing the Zn2+, Al3+ and Fe3+.

• Transactions of the Korean hydrogen and new energy society
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• v.33 no.4
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• pp.330-336
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• 2022

In order to evaluate the possibility as a separator in alkaline water electrolysis, the high temperature characteristics were evaluated by measuring the membrane resistance and durability of 5 types of commercial anion exchange membranes in 7 M KOH solution and at 80℃. The membrane resistance of AEM membrane measured in 7 M KOH solution and at 80℃ had a lower value of about 8-24 times compared to the other membranes. The durability of AEM membrane tested with the soaking time in 7 M KOH solution and at 80℃ showed a very good stability and that of FAAM40 and FAAM75-PK showed secondly a good stability. The thermal stability with the soaking time in 7 M KOH solution and at 80℃ of FAAM40 and FAAM75-PK membrane analyzed by thermo-gravimetric analysis showed a good stability compared to the other membranes.

• Korean Journal of Environmental Biology
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• v.17 no.4
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• pp.493-498
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• 1999

To verify the usefulness of enzyme activities as a index for the stability or maturity of organic refuse composting such as grape pomace, Vmax of $\beta$-glucosidase, cellobiohydrolase and alkaline phosphatase were measured. The peak values of all measured enzymes at the initial stage of composting were probably associated with easily degradable organic matter in the grape pomace and decreased gradually. But the activities of $\beta$-glucosidase and cellobiohydrolase were increased again rapidly whereas that of alkaline phosphatase remained approximately constant after 60 composting days. These results suggest that the increase of enzyme activities during the later periods of grape pomace composting process could be used as a index for their stability.