• Title/Summary/Keyword: alkaline

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Molecular Cloning and Expression of Alkaline Amylase Gene of Alkalophilic Bacillus sp. in Bacillus subtilis and Escherichia coli (알카리성 Bacillus sp.의 호알카리성 amylase 유전자의 Bacillus subtilis와 Escherichia coli로의 cloning과 발현)

  • Bae, Moo;Park, Shin-Hae
    • Microbiology and Biotechnology Letters
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    • v.17 no.2
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    • pp.160-164
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    • 1989
  • A 5.7Kb EcoRI fragment containing alkaline amylase gene of Bacillus sp. AL-8 obtained in the previons experiment (10) was transformed in B. subtilis via plasmid pUB110. The enzymatic proper-ties of the amylase produced by the transformants were Identical to those of the donor strain. Thus, the alkaline amylase activity from the transformant was maximum at pH 10 and 5$0^{\circ}C$. And the enzyme was very stable over the ranges of alkaline pH. In order to determine the location of the alkaline amylase gene within the 5.7Kb DNA fragment, the fragment was subcloned in E. coli. It was found that the alkaline amylase gene was located k EcoRI fragment of 3.7Kb.

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Scanning Tunneling Microscopy (STM)/Atomic Force Microscopy(AFM) Studies of Silicon Surfaces Treated in Alkaline Solutions of Interest to Semiconductor Processing

  • Park, Jin-Goo
    • Journal of the Korean institute of surface engineering
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    • v.28 no.1
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    • pp.55-63
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    • 1995
  • Alkaline solutions such as $NH_4$OH, choline and TMAH (($CH_3$)$_4$NOH) have been introduced in semiconductor wet processing of silicon wafers to control ionic and particulate impurities following etching in acidic solutions. These chemicals usually mixed with hydrogen peroxide and/or surfactants to control the etch rate of silicon. The highest etch rate was observed in $NH_4$OH solutions at a pH in alkaline solutions. It indicates that the etch rate depends on the content of $OH^{-}$ as well as cations of alkaline solutions. STM/AFM techniques were used to characterize the effect of alkaline solutions on silicon surface roughness. In SC1 (mixture of $NH_4$OH : $H_2$$O_2$ : $H_2$O) solutions, the reduction of the ammonium hydroxide proportion from 1 to 0.1 decreased the surface roughness ($R_{rms}$) from 6.4 to $0.8\AA$. The addition of $H_2$$O_2$ and surfactants to choline and TMAH reduced the values of $R_{p-v}$ and $R_{rms}$ significantly. $H_2$$_O2$ and surfactants added in alkaline solutions passivate bare silicon surfaces by the oxidation and adsorption, respectively. The passivation of surfaces in alkaline solutions resulted in lower etch rate of silicon thereby provided smoother surfaces.s.ces.s.

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Effects of Alkaline Treatment on the Characteristics of Chemical Pulps for Papermaking (알칼리 처리가 제지용 화학펄프의 특성에 미치는 영향)

  • Won, Jong-Myoung;Kim, Min-Hyun
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.43 no.3
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    • pp.106-112
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    • 2011
  • The effects of alkaline treatment on the WRV, crystalline structure and sheet structure of softwood and hardwood bleached kraft pulp were investigated. Sodium hydroxide and sodium carbonate were used as chemicals for alkaline treatment and two levels of alkali dosage (5%, 10%) were applied respectively. Alkali treated and untreated pulp were refined to three levels (550, 450 and 350 mL CSF). WRV of the alkali treated pulps depended on the alkaline type and concentration. It was found that the crystalline structures of softwood and hardwood pulp were not changed by refining. Sodium carbonate and lower concentration of sodium hydroxide treatment did not caused any modification of cellulose crystalline structure, while higher concentration of sodium hydroxide treatment caused the partial modification of cellulose crystalline structure. Alkaline treatment of hardwood bleached kraft pulp led to the shrinkage of fiber diameter and bulky structure of sheet. Alkaline treatment of softwood bleached kraft pulp did not cause the significant change in fiber shrinkage and bulk of sheet.

Effect of Alkaline-Earth Oxide Additives on Flexural Strength of Clay-Based Membrane Supports

  • Lee, Young-Il;Eom, Jung-Hye;Kim, Young-Wook;Song, In-Hyuck
    • Journal of the Korean Ceramic Society
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    • v.52 no.3
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    • pp.180-185
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    • 2015
  • Low-cost ceramic membrane supports with pore sizes in the range of $0.52-0.62{\mu}m$ were successfully prepared by uniaxial dry compaction method using inexpensive raw materials including kaolin, bentonite, talc, sodium borate, and alkaline-earth oxides in carbonate forms (e.g., $MgCO_3$, $CaCO_3$, and $SrCO_3$). The prepared green supports were sintered at $1000^{\circ}C$ for 8 hr in air. The effect of alkaline-earth oxide additives on the flexural strength of clay-based membrane supports was investigated. The porosity of the clay-based membrane supports was found to be in the range of 33-34%. The flexural strength of the clay-based membrane supports with 1% alkaline-earth carbonates was found to be in the range of 42.8-52.7 MPa. The addition of alkaline-earth carbonates to clay-based membrane supports resulted in large increases (47-80%) in the flexural strength of the membrane supports, compared to that of membrane supports without alkaline-earth carbonates. The typical flexural strength of the clay-based membrane support with 1% $SrCO_3$ was 52.7 MPa at 33.8% porosity.

Heterotrophic Bacterial Community and Alkaline Phosphatase Releasing Bacteria in Lake Soyang (소양호에서의 종속영양세균의 종구성 및 Alkaline phosphatase 분비 세균에 관한 연구)

  • 이동훈;안태석;조규송
    • Korean Journal of Microbiology
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    • v.28 no.3
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    • pp.204-209
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    • 1990
  • The total and heterotrophic bacterial distributions, compositions and alkaline phosphatese actibities were analyzed in Lake Soyang from Sep. 1987 to Aug. 1988. The heterotrophic bacteria was small portion, 0.07-2.63% of total bacterial number which ranged from $3.2{\times}10^{5}$ to $3.2{\times}10^{6}$ cells/${\mu}\ell$. The composition of bacterial community was less diverse in summer and at the fish farm site and Peridinium blooming site. Pseudomonas and Flavo bacterium were the dominant genera in all sites. The highest proportion and activity of alkaline phsophatase was appeared in Flavobacterium, while Pseudomonas was the most predominant group.

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Purification and Properties of Alkaline Protease from Streptomyce sp. YSA-130 (Streptomyces sp. YSA-130이 생산하는 Alkaline Protease의 정제 및 특성)

  • 윤성우;이강표;유주현;신철수;오두환
    • Microbiology and Biotechnology Letters
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    • v.17 no.4
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    • pp.358-364
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    • 1989
  • A crystalline alkaline pretense- producing Streptomyce sp. YSA-130 was isolated from soil in alkaline medium(pH 10.5). The optimum culture condition of Streptomyce sp. YSA-130 for the production of alkaline protease was as follows; 2.0% soluble starch, 1.0% soytone, 0.3% $K_2$HPO$_4$, 0.02% MgSO$_4$.7$H_2O$, 0.8% Na$_2$CO$_3$, pH 10.5, 3$0^{\circ}C$, and 12 hr. The alkaline pretense from the culture broth of Streptomyce sp. YSA-130 was purified about 24 folds by ammonium sulfate precipitation , dialysis, DEAE-cellulose ion exchange chromatography, gel filtration on Sephadex G-15 and crystallization. Optimum temperature and pH of purified enzyme were 6$0^{\circ}C$, and 11.5. Temperature and pH stability of purified enzyme were 5$0^{\circ}C$, and 5.5-12.0. Calcium ion was effective to stabilize the enzyme at higher temperature. The molecular weight of the purified enzyme was approximately 30,000. The purified enzyme was inactivated by diisopropyl flurophosphate(DFP) but not affected by metal ion, EDTA, sulfhydryl reagent and stable detergent.

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Characteristics of Alkaline and Acid Phosphatase in Echinostoma hortense (호르텐스극구흡충에서 Alkaline Phosphatase 및 Acid Phosphatase의 특성)

  • 양용석;김인식;임지애;강성구;박주연
    • Biomedical Science Letters
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    • v.5 no.1
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    • pp.119-129
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    • 1999
  • This study was aimed to investigate the enzyme-histochemical localization and characteristics of alkaline and acid phosphatase extracted from adult of Echinostoma hortense. Using the Gomori calcium stain and the Gomori lead nitrate satin method, we found that the alkaline and acid phosphatases were localized mostly in the intestine, vitellaria and pharynx of Echinostoma hortense. The three isozymes of alkaline phosphatase and two isozymes of acid phosphatase were separated from Echinostoma hortense by electrophoresis. The isozymes of alkaline phosphatase were 145.9, 207.5, 220.8 kDa and the isozymes of acid phosphatase were 179.5 and 209.4 kDa. The activity of alkaline phosphatase was denatured completely after heating at 9$0^{\circ}C$ for 12 seconds. The optimum pH and temperature for activity of alkaline phosphatase were about pH 9 and 4$0^{\circ}C$, while the optimum pH for activity of acid phosphatase was about pH 5. The maximum activity of alkaline phosphatase was at 189 unit, but maximum activity of acid phosphatase was at 71 unit As the result from above, we observed that alkaline and acid phosphatases funtion mainly in the alimentary tract and vitellaria. Echinostoma hortense performs the parasitism in the intestine of host by using proper isozyme of phosphatase.

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Production and Properties of Alkaline Pretense from Bacillus sp. Strain in Thermophilic and Alkaline Condition (Bacillus속 AP-5 균주의 고온성 알카리 배양에 따른 Alkaline Pretense의 생성 및 성질)

  • 이광배
    • Journal of environmental and Sanitary engineering
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    • v.5 no.2
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    • pp.103-110
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    • 1990
  • For production of thermophilic and alkaline protease, Bacillus sp. strain AP-5 was isolated from a compost. The production of the protease was reached at maximum for 4 days at $55^{\circ}$ in standing culture. Chitin and Cellulose as carbon source, and Skim Milk as nitrogen source were favorable for the production of the enzyme. Optimal temperature and optimal pH of the enzyme was $55^{\circ}$ and 11, respectively. Metal ion didn't effect on the enzyme activity, the protease was very stable at heat treatment of 30 min at $55^{\circ}$.

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Bone Alkaline Phosphatase Levels in Serum of Normal Dogs (정상적인 개에서의 Serum Bone Alkaline Phosphatase의 활성치)

  • 조성진;김남수;최인혁
    • Journal of Veterinary Clinics
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    • v.14 no.1
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    • pp.65-69
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    • 1997
  • The bone alkaline phosphatase(BALP) in 130 sera of normal dogs were assayed according to the lectin precipitation method of Rosalki and Foo. The serum BALP activities showed a wide variation as $23.27({\pm}14.73)$ IU/L in young dogs from 6weeks to 12 months old and were lower in magnitude as $9.24({\pm}3.36)$ IU/L in elder dogs from 1 years to 6years old. The serum BALP activities in normal dogs were no significant correlation in sex.

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Regulation of extracellular alkaline protease biosynthesis in a strain of streptomyces sp. (Streptomyces sp. 일주에서 균체외 호염기성 단백질분해 효소의 생합성 조절)

  • 신현승;이계준
    • Korean Journal of Microbiology
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    • v.24 no.1
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    • pp.32-37
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    • 1986
  • In fermentation studies it revealed that Streptomyces sp. SMF 3001 started to synthesize extracellular alkaline protease from early exponential phase of cell growth. The biosynthesis of the alkaline protease was greatly induced by skim milk as a sola nitrogen source and further stimulation was observed under inorganic sulphur limited culture. However, it was found that the biosynthesis was apparently repressed by $NH_4^+$ and free amino acids, specially by cysteine. It was considered that the strain SMF 301 of Streptomyces sp. would produce the alkaline protease for the uptake of sulphur compounds from protein contained in the culture broth.

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