• Title/Summary/Keyword: Optimum Ph

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A Study on the Alkaline Protease Produced from Bacillus subtilis (Bacillus subtilis가 생산하는 Alkaline Protease에 관한 연구)

  • Chang, Shin-Jae;Kim, Yoon-Sook;Sung, Ha-Chin;Choi, Yong-Jin;Yang, Han-Chul
    • 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.

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Effects of pH, Sucrose and Vitamins on the Growth and Tropane Alkaloid Production of Hairy Roots of Datura stramonium var. tatula Torr. (독말풀(Datura stramonium var. tatula Torr.) 모상근의 성장과 tropane alkaloid 생성에 미치는 pH, 서당 및 비타민의 영향)

  • 양덕조;강현미;이강섭;김용해;양덕춘
    • Korean Journal of Plant Tissue Culture
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    • v.24 no.3
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    • pp.143-148
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    • 1997
  • The optimum concentrations of pH, sucrose and vitamins for the growth and tropane alkaloid production of hairy root clone DTLA9 (best growth line) were investigated. The optimum pH in growth and tropane alkaliod production of DTLA9 clone in SH (Schenk and Hildebrandt, 1972) basal medium without growth regulator were pH 6.3 and 6.5, respectively. Also, the optimum sucrose concentration in growth and tropane alkaliod production in the same medium were 3.0 and 2.8%, respectively. The optimum concentrations of ascorbic acid, D-pantothenate, nicotinic acid, pyridoxine, riboflavin, and thiamine on the growth of DTLA9 clone in SH basal medium without vitamins were 0.1 mM, 0.003 mM, 0.07 mM, 0.002 mM, 0.025 mM, and 0.01 mM, respectively. In particular, supplement of 0.1 mM ascorbic acid to SH basal medium without vitamins stimulated the tropane alkaloid production.

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Studies on 5'-Phosphodiesterase produced by microoganisms - Part. I. On the 5'-Phosphodiesterase of Penicillium sclerotiorum - (미생물(微生物)에 의(依)한 5'-Phosphodiesterase생산(生産)에 관(關)한 연구(硏究) - 제1보(第一報) penicllium sclerotiornm의 5'-Phosphodiesterase에 대(對)하여 -)

  • Kim, Ho-Sik;Lee, Ke-Ho
    • Applied Biological Chemistry
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    • v.4
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    • pp.11-16
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    • 1963
  • (1) The 30 strains of Penicillia and the 52 strains of Aspergilli have been screened for their producibility of 5'-Phosphodiesterase, and Penicillium sclerotiorum 7321, Penicillium sp M-11 and Penicillium citrinum UV-mutant 2032-72 were selected as having high 5‘-Phosphodiesterase activity. (2) Using the wheat bran medium the 5‘-Phosphodiesterase production was reached at maximum state by the plate culture for 10 days at $30^{\circ}C$ (3) The optimum conditions of the 5'-Phosphodiesterase activity of Penicillium sclerotiorum 7321 and Penicillium sp M-11 were pH 4.0 at $62.5^{\circ}C$, while the optimum condition of the 5'-Phosphodiesterase activity of Penicillium citrinum UV-mutant 2032-72 was pH 5.0 at $50^{\circ}C$.

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Studies on the Preservation of Soybean Paste (Part 1) Inhibition of the Growth of Film-forming Yeast (된장의 변질방지에 관한 연구 (제1보) 산막효모의 발육억제)

  • 차원섭
    • Microbiology and Biotechnology Letters
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    • v.6 no.2
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    • pp.81-84
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    • 1978
  • Film-forming yeasts were isolated from deteriolated soybean paste and after identification factors affected on the growth of the organisms were studied to provide information on the protection of the product from deteriolation. The isolated yeasts were identified as Pichia membranaefaciens. The yeasts could grow within the temperature limit of 10$^{\circ}C$ and 68$^{\circ}C$ with optimum at 25$^{\circ}C$. The optimum pH was 6.0 and the growth was reduced in order at 7.0, 5.0, 8.0 and 4.0. The maximum concentration of sodium chloride in Hayduck solution was 15% above which the yeasts ceased to grow.

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Studies on Growth Characteristics of lactobacillus brevis Isolated from Kimchi - Optimization of Nutrient Composition in Sourdough Media - (김치에서 분리한 Lactobacillus brevis의 생장 특성에 관한 연구( I ) - Sourdough 배지의 영양 조성 최적화 -)

  • 신언환
    • The Korean Journal of Food And Nutrition
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    • v.15 no.3
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    • pp.215-219
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    • 2002
  • Growth characteristics of sourdough lactic acid bacteria was investigated to obtain basic informations for sourdough starter. The optimum temperature and pH on bacterial growth and lactic acid production of Lactobacillus brevis UC-22 in sourdough broth were 35'E and around pH 5.5, respectively. And the optimum concentrations of the carbohydrate sources added to the broths was 2% maltose. The acidity significantly increased during growth by Lactobacillus brevis UC-22 fur 18 hours while pH significantly decreased during growth.

Spectrophotometric Determination of Platinum (IV) with 2-Oximino-1-indanone (2-Oximino-1-indanone을 이용한 Pt(IV) ion의 정량에 관한 연구)

  • 김정균;유미경;원미숙;심윤보;고영심
    • YAKHAK HOEJI
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    • v.28 no.2
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    • pp.61-67
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    • 1984
  • A method is described for the spectrophotometric determination of platinum (IV) with 2-oximino-1-indanone based on solvent extraction of Pt:2-oximino-1-indanone complex. The 2-oximino-1-indanone reacted with Pt(IV) to form a dark-orange complex which shows a characterisic maximum absorption at 342nm. The optimum PH for the platinum extraction lies between 5.4~8.0. Beer's law obeys up to 0.98-16.3ppm of platinum (IV) and the molar absorption coefficient is $1.06{\times}10^{-4}L.mol^{-1}.cm^{-1}$. The relative standard deviation of the method was $\times2.1%$. The composition of the complex is estimated to be Pt : In= 1 : 1, by the mole ratio method and ion exchange resin experiment. The optimum condition for the determination of platinum has been studied in detail. The 2-oximin-1-indanone is found to be a selectivereagent for the determination of platinum, since the synthesixed 2-oximino-1-indanone did not react with other metals such as cobalt, cadmium, copper, manganese nickel, iron, lead and zinc, to form the complex. In this studies, we have also clarified Sindhwani and Singh's spectrophotometric determination data of various metals with acenaphthenequinone monooxime (Talanta 20,248, 1973), whose results were not correct.

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Practicality of Woo's Super Rudder Controlling (우즈 수퍼러더조선법의 실용성에 관하여)

  • 우병구
    • Journal of the Korean Institute of Navigation
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    • v.17 no.3
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    • pp.69-76
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    • 1993
  • In harbour the practical shiphandlers should have a expert knowledge of systematically reducing head-way and keeping ship's positions to the final position with confidence and under control. But now in the practical approaches we do not have any special maneuvers of controlling the ship effi-ciently regarding the headway and approaches except some existing reduction of speeds according to the Weight-to-Power Ratio, use of astern power and Rudder Cycling. Consequently this study put Woo's Super Rudder Controlling originally developed by Captain Woo, Ph. D. to practical use as a special maneuvers in the port approaches. The conclusions of this paper are drawn as follows : 1) Optimum standard and desirable controls in combination of three engine speeds with three yaw ang-les were proposed for the practical shiphandlers, 2) According to simulation of the pilotships the Super advances are 10.5 ship lengths for Full full full maneuvers, and 7.9 ship lengths for Full half maneuvers approximately, 3) Approach maneuvers to anchorages by trying Woo's Super Rudder Controlling saved about 30% of total standby time in comparison with the existing Weight-to-Power Ratio maneuvers in the Pusan and Kwang Yang ports.

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Production of Mannooligosaccharides by the Penicillium purpurogenum Mannanase (Penicillium purpurogenum 유래의 Mannanase에 의한 Mannooligosaccharide의 생산)

  • Park, Gwi-Gun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.23 no.3
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    • pp.509-514
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    • 1994
  • Penicillium purpurogenum , which produces a copra galactomannan degrading enzyme extracellularyl, was isolated from soil , and its properties and formation condition of mannooligosaccharides were investigated. The optimum ph and temperature for the activity of the mannanase were 5.5 and 55$^{\circ}C$, respectively. The mannanase was stable in between pH 3.5 and 7.0 after 2 hr incubation at 3$0^{\circ}C$ lost 90% of the original activity after incubation at 55$\AA$ and pH 5.5 for 2 hr. With two different substrate concentration, hydrolysis of white coprameal proceeded rapidly at the early stage of the reaction, but gradually solwed thereafter especially at a higher concentration of copra meal (20 %). The enzyme hydrolyzed white copra meal to monosaccharides, mannobiose and mannotriose at the final stage of the reaction.

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Characteristics Evaluation of Thin Films Formed on Mg-Al Alloy in Various Chemical Conversion Solution Conditions (다양한 화성처리 용액 조건에서 마그네슘-알루미늄 합금위에 형성된 박막의 특성 평가)

  • Jang Seok-Ki;Kim Seong-Jong;Kim Jeong-Il
    • Journal of Advanced Marine Engineering and Technology
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    • v.29 no.1
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    • pp.98-106
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    • 2005
  • The chemical conversion film formed on magnesium alloy was investigated by using the colloidal silica with some parameters such as solution pH. temperature, solution conditions, and treatment time. Moreover. the solutions consisted of colloidal silica titanium sulfate, and cobalt ions were used for the colloidal silica film to having a good corrosion resistance and adhesion properties. It was thought that the film at 298K was made with combination of Si-O. The quantity of film formed at high temperature such as 333K and 353K is smaller than dissolved quantity during chemical conversion treatment. Adding $CoSO_4$ to the colloidal silica solution enhanced the adhesion force between the silica film and magnesium substrate, The optimum conditions for the chemical conversion treatment solution were PH 2.90 s treatment, and 298K.

Fabrication and Characterization of High Purity Al2O3 by Decomposition of Selicite (세리사이드 분해에 의한 고순도 Al2O3의 제조 및 특성에 관한 연구)

  • 이경희;박한수;송명신
    • Journal of the Korean Ceramic Society
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    • v.24 no.5
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    • pp.431-436
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    • 1987
  • High purity Al2O3 has been extracted from serlcite of clayminerals, selicite was treated by H2SO4(2N∼18N) solution, NH4OH treatment(PH8.5∼10.0) and metallic impurities such as Fe were removed by NaOH treatment. The tendency of extraction yield of ${\alpha}$-Al2O3 have been investigated by relating reaction time, acid concentration. Reaction products were analyzed by DT-TGA, chemical analysis and X-ray diffractometer. Prepared ${\alpha}$-Al2O3 power is fired in air at 1400$^{\circ}C$, 1600$^{\circ}C$ 2hr. The results are as follows; 1. The most suitable extracting conditions of ${\alpha}$-Al2O3 from Selicite were N-H2SO4, 120 min acidtreating time. 2. The optimum pH condition was 9.0. 3. Physical properties of sintered Al2O3 bodies were as follows. Relative density is 99%. Water absorption is 0.26%. Rock well hardness is 89.

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