• Title/Summary/Keyword: optimum growth

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Lead Tolerance Profile of Pseudomonas Stuzeri in Liquid Culture

  • Kim, Su-Jung;Jung, A-Young;Joo, Jin-Ho
    • Korean Journal of Environmental Agriculture
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    • v.26 no.4
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    • pp.332-336
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    • 2007
  • Pseudomonas stutzeri strain KCCM 34719 was used in this experiment to determine the effects of increasing Pb(II) concentrations on its growth rate. To obtain optimum growth conditions, strain KCCM 34719 was cultivated in nutrient broth under various conditions, such as temperature, pH, and NaCl concentration. Optimal conditions for cell growth were $30^{\circ}C$ of temperature, 8.0 of pH, and 3% of NaCl concentration, respectively. Growth response of bacterial cell to Pb(II) showed tolerance to concentrations ranging from 10 to 100 mg ${\ell}^{-1}$ in liquid culture, following a growth pattern similar to the control. Growth rate was greatly inhibited at 200 mg ${\ell}^{-1}$ of Pb(II).

Studies on Koji for Optimum Conditions of Growth and Idenfication of Aspergillus spp.(Part2) (장류용 강력국균 연구 2)

  • 이계호;장건형
    • Korean Journal of Microbiology
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    • v.2 no.1
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    • pp.17-18
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    • 1964
  • Ke Ho Lee and Kun Hyung Chang (Army Research and Testing Lab.): Studies on koji for optimum condition of growth and identification of Aspergillus spp. Cpart 2). Kor. J. Microbiol. Vol. 2, No. 1, p. 17-18 (1964). The experiments reported in this paper are concerned with the identifications, the growth conditions and lethal temperatures of the three strains of Aspergillus spp. which have been isolated from the soils and Meju (fermented soy bean in Korea). The results obtained in the light of the manual of Raper and Thom for identification of the Genus, Aspergillus, have been shown that the three strains of Aspergillus spp. are pertained to Aspergillus flavusoryzae group. The optimum temperature, pH and the lethal temperatures of the Aspergillus spp. have been measured.

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Studies on the osmophilic red colores yeast (II) (내염성 적색효모에 관한 연구 2)

  • 이택수;이석건
    • Korean Journal of Microbiology
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    • v.8 no.3
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    • pp.103-106
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    • 1970
  • The cultural conditions of the osmophilic red color yeasts (Strain L${1$, $L_2$, $L_3$ and $L_4$) isolated and identified in the previous report were examined and the results obtained were as follows ; 1. The optimum medium for growth of these osmophilic red color yeasts was soy sauce medium. 2. These strains were grown exceedingly well on the medium containing 3 percent of NaCl but somewhat restrained on the medium containing 6% or more. 3. The optimum temperautre for growth of these strains was $25^{\circ}C$ and their lethal temperature was $68^{\circ}C$(treatment for 5 minutes). 4. The optimum pH for growth of these strains was 6.0.

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Effect of Incubation Period, Temperature and pH on Mycelial Growth of Cylindrocarpon destructans (Zinssm.) Scholten Causing Root-rot of Ginseng (배양기간, 온도, pH가 인삼 근부병균 Cylindrocarpon destructans (Zinssm.) Scholten의 균사생육에 미치는 영향)

  • 조대휘;안일평
    • Journal of Ginseng Research
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    • v.19 no.2
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    • pp.181-187
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    • 1995
  • Cylindvocarpon destmtalns isolate CY-92-01, pathogen of root-rot of Panax ginseng showed t the maximum mycelial growth on the Czapek solution agar among the thirteen kinds of media. Five isolates (Isolate CY-92-01, CY-92-03, CY-92-07, CY-94-01, CY-94-02) of C. destructan from various growth stages of p. ginseng recovered from several geographical sites also showed maximum growth in the Czapek-Dox broth compared with potato dextrose broth and V-8 juice broth. Rapid growth rate was maintained until 12 days after inoculation on the Czapek-Dox broth and mycelial weight was somewhat constant until 20 days. After 30 days of incubation, the mycelial weight began to decrease. The fungal growth occurred from 5$^{\circ}C$ to $25^{\circ}C$ and optimum temperature for growth was 2$0^{\circ}C$. Mycelial weight orderly decreased at 15, 25, 10, and 5$^{\circ}C$. Quantitative measurement was impossible at 5$^{\circ}C$. No fungal growth was occurred at the temperature higher than 3$0^{\circ}C$. Growth was observed at all tested pH ranges from 2.8 to 8.0. Optimum pH for growth was 4.0~5.0 followed by pH 3.3~3.5 and 5.4~6.0. The least growth occurred at pH 2.8.

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Studies on the Amylase of Rhizopus(III) (Rhizopus의 아밀라제에 관한 연구 3)

  • 이영녹;이평우
    • Korean Journal of Microbiology
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    • v.11 no.3
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    • pp.121-128
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    • 1973
  • In order to clarify the best cultural conditions of Rhizopus niveus the effects of aeration, pH and various nutrients, such as different carbon and nitrogen sources, vitamins, and growth substances, on the mycelial growth were studied through liquid culture, and amylase activities of the fungus at different cultural periods were measured. Soluble starch, xylose and galactose are excellent sources of carbon for growth of the fungus. Sorbose and lactose are utilized slightly for growth. peptone, ammonium sulfate and alanine are excellent nitrogen sources for growth, tyrptophane nad potassium nitrate are utilized slightly for growth and sodium nitrite is not utilized. Thiamine nad gibberellin are excellent growth substances for the fungal growth, and biotin, nicotinamide and indole acetic acid (IAA) are also effective. Rhizopus niveus grows better at rotatory culture than at stationary culture and earlier growth of the fungus increases remarkably at rotatory culture. Optimum pH than at pH3. Growth increases linerly with an increase of soluble starch content up to 100g per liter medium, but 5 grams of ammonium sulfate per liter is the optimum nitrogen concentration for growth, if Pfeffer's medium is employed. Amylase activities of Rhizopus at different cultural periods showed that the maximum amylase production takes place after the cell population has reached its peak in the culture. Dextrinogenic amylase production has reached maximum at stationary phase, and maximum saccharogenic maylase production takes place in the pahse of negative gorwth acceleration.

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A Study on the Optimum Planting Density of Urban Public Park in Seoul-In Case of the Munjung-Family APT. Complex- (서울지역 공원녹지 식재밀도의 적정성에 관한 연구 -문정 훼미리 아파트 단지내 공원녹지를 사례로)

  • 이준복;심경구
    • Journal of the Korean Institute of Landscape Architecture
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    • v.26 no.2
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    • pp.219-228
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    • 1998
  • This study was investigated a optimum planting density of urban public park in seoul. Eight species commonly usd as landscape plants were selected. The survey was conducted to measure hight and width of the trees by five years interval. The results are summarized as follows. The average annual growth rates of the trees after planting were 7.4% in height 11.7% in width. Faster grown trees than average growth rate of the survey tres wee Metasequoia, glyptostroboides and Acer buergerianum, While the slower grown trees were Pinus koraiensis, Ginkgo biloba and Zelkova serrata. The average grown trees were Pinus strobus, Pinus densiflora and Acer palmatum . The planting density of survey area was 0.20tree/$m^2$. The optimum planting density was kept until five years after planting, however overcrowding density was found beyond five years after planting. This study also found the density of ten years after planting reaches about 3 times of optimum density.

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Media Optimization for L-tryptophan Production by Genetically Engineered Klebsiella pneumoniae (유전자 조작한 Klebsiella pneumoniae로부터 L-트립토판 생산을 위한 발효배지 조건)

  • 김천규;정용섭;홍석인
    • Microbiology and Biotechnology Letters
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    • v.22 no.5
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    • pp.557-560
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    • 1994
  • The optimum medium composition for the production of L-tryptophan with Klebsiella pnuemoniae pheA tyrA trpE trpR/pSC 101-trp$^{+}$ and the effect of precusors in the optimum medium were studied. The specific growth rate in the optimum medium was almost the same as that in the basal medium, the former showing 1.01 and the latter 1.07 hr $$^{-1}$, but the produced tryptophan was increased 45% in the optimum medium. The maximum amount of produced tryptophan was 159 mg/l within 14 hours. Tryptophan production was ceased by casamino acid addition over 4 g/l in medium, but cell maSS increased with its addition. Indole and anthranilate as precusors had toxic effect on growth and tryptophan production at experimented concentration range (over 20 mg/l), but L-serine had good effect on tryptophan production, resulting in 175 mg/l tryptophan within 14 hours.

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Development of an Algorithm for Searching Optimal Temperature Setpoint for Lettuce in Greenhouse Using Crop Growth Model (작물생장모델을 이용한 상추의 온실 최적설정온도 탐색 알고리즘의 개발)

  • 류관희;김기영;김희구;채희연
    • Journal of Biosystems Engineering
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    • v.24 no.5
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    • pp.445-452
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    • 1999
  • This study was conducted to develop a searching algorithm for optimal daily temperature setpoint greenhouse. An algorithm using crop growth and energy models was developed to determine optimum crop growth environment. The results of this study were as follows: 1. Mathematical models for crop growth and energy consumption were derived to define optimal daily temperature setpoint. 2. Optimum temperature setpoint, which could maximize performance criterion, was determined by using Pontryagin maximum principle. 3. Dynamic control of daily temperature using the developed algorithm showed higher performance criterion than static control with fixed temperature setpoint. Performance criteria for dynamic control models were with simulated periodic weather data and with real weather data, increased by 48% and 60%, respectively.

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Growth of Spirulina platensis in Effluents from Wastewater Treatment Plant of Pig Farm

  • Hong, Seok-San
    • Journal of Microbiology and Biotechnology
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    • v.3 no.1
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    • pp.19-23
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    • 1993
  • Spirulina platensis NIES 39 was grown in effluents from a wastewater treatment plant utilizing activated sludge process at a pig farm to reduce pollutants and to produce feed resources. The addition of 2 g/l NaCl was required for the growth of S. platensis in the effluents with about 100 mg/l ammonia nitrogen concentration. The growth was stimulated by the addition of 2 g/l sodium bicarbonate and 4 mg/l ferrous sulfate. The microorganism grew well at pH 8~11, and the optimum pH for the growth was 10. The algal concentration of 1.1 g/l was attained after 8 days of growth at the optimum condition with the removal of 95% ammonia nitrogen and 34% phosphorus.

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Effect of Culture Conditions on Production of Polysaccharides and Growth Rate of Porphyridium cruentum (Porphyridium cruentum의 성장 및 당질 생산에 미치는 배양 조건의 영향)

  • Joo, Dong-Sik;Choi, Soon-Yeong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.41 no.6
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    • pp.446-451
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    • 2008
  • The growth of Porphyridium cruentum and its porphyran polysaccharide production were measured as functions of light intensity, temperature, light quality (fluorescent, blue, red, and green) and nitrate concentration. The optimum light intensity, temperature, and nitrate concentration for the growth of Porphyridium cruentum and for its polysaccharide production were 1,400 lx, $25^{\circ}C$, and 0.03%, respectively. The maximum cell concentration and polysaccharide content under the optimum conditions were 1.95 and 0.23 mg/mL, respectively. Light quality did not influence growth or polysaccharide production. The best results for growth and polysaccharide production were obtained using fluorescent light.