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Isolation and Characterization of Ethanol-Producing Schizosaccharomyces pombe CHFY0201

  • Choi, Gi-Wook;Um, Hyun-Ju;Kim, Mi-Na;Kim, Yule;Kang, Hyun-Woo;Chung, Bong-Woo;Kim, Yang-Hoon
    • Journal of Microbiology and Biotechnology
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    • v.20 no.4
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    • pp.828-834
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    • 2010
  • An ethanol-producing yeast strain, CHFY0201, was isolated from soil in South Korea using an enrichment technique in a yeast peptone dextrose medium supplemented with 5% (w/v) ethanol at $30^{\circ}C$. The phenotypic and physiological characteristics, as well as molecular phylogenetic analysis based on the D1/D2 domains of the large subunit (26S) rDNA gene and the internally transcribed spacer (ITS) 1+2 regions, suggested that the CHFY0201 was a novel strain of Schizosaccharomyces pombe. During shaking flask cultivation, the highest ethanol productivity and theoretical yield of S. pombe CHFY0201 in YPD media containing 9.5% total sugars were $0.59{\pm}0.01$ g/l/h and $88.4{\pm}0.91%$, respectively. Simultaneous saccharification and fermentation for ethanol production was carried out using liquefied cassava (Manihot esculenta) powder in a 5-l lab-scale jar fermenter at $32^{\circ}C$ for 66 h with an agitation speed of 120 rpm. Under these conditions, S. pombe CHFY0201 yielded a final ethanol concentration of $72.1{\pm}0.27$ g/l and a theoretical yield of $82.7{\pm}1.52%$ at a maximum ethanol productivity of $1.16{\pm}0.07$ g/l/h. These results suggest that S. pombe CHFY0201 is a potential producer for industrial bioethanol production.

Progesterone Hydroxylation by Rhizopus nigricans(I): The effects of reaction conditions (Rhizopus nigricans 에 의한 Progesterone 의 Hydroxylation(I): 반응 조건의 영향)

  • Kim, Myung-Hee;Kim, Mal-Nam
    • The Korean Journal of Mycology
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    • v.15 no.1
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    • pp.23-28
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    • 1987
  • Physicochemical factors influencing the $11{\alpha}$, hydroxylation of progesterone by Rhizopus nigricans Ehrenberg were studied. The higher is the concentration of progesterone. the shorter time is need to attain maximum yield in the $11{\alpha}-hydroxyprogesterone$. High concentration in progesterone was supposed to inhibit the hydroxylation reaction of the $11{\alpha}-hydroxyprogesterone$. The range of optimum pH and temperature appeared to be rather broad and these conditions were similar to those of optimum growth of the mycelia. Agitation at a higher speed than a certain limit, and the presence of sugars accelerated the $11{\alpha}-hydroxyprogesterone$ reaction. Glucose was found to be more effective for the reaction using spores rather than mycelia as enzyme sources. Organic solvents were proved to supress the enzyme activity, which decreased with increase in the concentration of the organic solvents and in the time for pretreatment with the solvents.

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Removal of Chlorine from Fly Ash in Municipal Solid Waste Incineration Ash by Water Washing (수세에 의한 생활폐기물 소각재 중 비산재로부터 염소성분의 제거)

  • 안지환;한기천;김형석
    • Resources Recycling
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    • v.10 no.5
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    • pp.36-43
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    • 2001
  • The chlorine component in fly ash from municipal solid waste incineration ash was removed by water washing for the purpose of recycling fly ash as a raw material of ordinary portland cement. The samples were a different kind of 리y ashes using $Ca(OH)_2$and NaOH as media of wet scrubber for flue gas cleaning. The content of soluble salts of fly ash using $Ca(OH)_2$and NaOH was 32.8%, 50.1% and the content of chlorine component, 22.9% and 26.0% respectively, which was KCl, NaCl, CaC1OH mainly. When each fly ash was washed using water under conditions of a agitation speed of 300 rpm, a liquid to solid ratio of 10, most soluble salts in fly ash were dissolved within 30 minutes and the content of chlorine component in ash was diminished to the content of 4.4%, 2.O% at $20^{\circ}C$ and 1.7%, 0.8% at $50^{\circ}C$ respectively. And the main compound of residual chlorine component in ash after water washing was friedel`s salt ($3CaO.A1_2$$O_3$.$CaCl_2$.$10H2$O). From analysis results of water quality for wastewater by water washing, the components exceeding discharged wastewater standard were only Pb and Cd. But As pH was controlled to 10 with addition of $CO_2$(g) or $Na_2$$_CO3$in water, the concentration of heavy metals such as Pb and Cd was also under discharged wastewater standard.

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Growth of Yeasts in Alcohol Distiller′s Waste of Dried Sweet Potato for Single-cell Protein Production and BOD Reduction (절간고구마원료 주정폐액을 이용한 단세포단백질의 생산 및 폐액의 BOD제거)

  • 이형춘;구영조;민병용;이홍근
    • Microbiology and Biotechnology Letters
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    • v.10 no.2
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    • pp.95-100
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    • 1982
  • Torulopsis candida FRI YA-15, a selected yeast, was cultivated in alcohol distiller's waste-filtrate of dried sweet potato for microbial protein production and BOD reduction. The General composition of waste-filterate was BOD$_{5}$ 15700 ppm, COD 36800 ppm, reducing sugar 3300 ppm, total nitrogen 910 ppm, total solids 51800 ppm and ash 390 ppm. The pH of waste was 3.85. The yield to the medium of T. candida cultivated in shake-flask at $25^{\circ}C$ for 48 hrs was 3.38g/$\ell$ and effectiveness in reducing BOD$_{5}$ and COD of waste was 38.9% and 31.8%, respectively. In batch cultivation using 3 $\ell$-jar fermenter, maximum yield to the medium reached 3.2g/$\ell$after 28 hrs cultivation under the condition of temperature 35$^{\circ}C$, initial pH 4.0, aeration rate 2vvm, agitation speed 100rpm. Dry yeast was composed of crude protein 47.98% and ash 5.23%.

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Development of Miniaturized Culture Systems for Large Screening of Mycelial Fungal Cells of Aspergillus terreus Producing Itaconic Acid

  • Shin, Woo-Shik;Lee, Dohoon;Kim, Sangyong;Jeong, Yong-Seob;Chun, Gie-Taek
    • Journal of Microbiology and Biotechnology
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    • v.27 no.1
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    • pp.101-111
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    • 2017
  • The task of improving a fungal strain is highly time-consuming due to the requirement of a large number of flasks in order to obtain a library with enough diversity. In addition, fermentations (particularly those for fungal cells) are typically performed in high-volume (100-250 ml) shake-flasks. In this study, for large and rapid screening of itaconic acid (IA) high-yielding mutants of Aspergillus terreus, a miniaturized culture method was developed using 12-well and 24-well microtiter plates (MTPs, working volume = 1-2 ml). These miniaturized MTP fermentations were successful, only when highly filamentous forms were induced in the growth cultures. Under these conditions, loose-pelleted morphologies of optimum sizes (less than 0.5 mm in diameter) were casually induced in the MTP production cultures, which turned out to be the prerequisite for the active IA biosynthesis by the mutated strains in the miniaturized fermentations. Another crucial factor for successful MTP fermentation was to supply an optimal amount of dissolved oxygen into the fermentation broth through increasing the agitation speed (240 rpm) and reducing the working volume (1 ml) of each 24-well microtiter plate. Notably, almost identical fermentation physiologies resulted in the 250 ml shake-flasks, as well as in the 12-well and 24-well MTP cultures conducted under the respective optimum conditions, as expressed in terms of the distribution of IA productivity of each mutant. These results reveal that MTP cultures could be considered as viable alternatives for the labor-intensive shake-flask fermentations even for filamentous fungal cells, leading to the rapid development of IA high-yield mutant strains.

Purification and Characterization of Two Alkaline Proteases Produced by Pseudomonas sp. BK7

  • 이은구;박은희;현형환
    • Journal of Microbiology and Biotechnology
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    • v.10 no.5
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    • pp.667-667
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    • 2000
  • Pseudomonas sp. BK7, an alkalophile, displayed the highest growth and protease activity when grown in a fermenter which was controlled at a pH level of 9.0, and the enzyme production was significantly enganced by the increase of agitation speed. Two formas of alkaline proteases (BK7-1 and BK7-2) were fractionated and purified to near homogeneity. Protease BK7-1 was purified through CM-Sepharose CL-6B and Sephadex G-75 column chromatographies, and Protease BK7-2 was purified through CM-Sepharose CL-6B and Sephadex G-75 column chromatographies, and Protease BK7-2 was purified through CM-Sepharose CL-6B, DEAE-Sepharose, and Sephadex G-75 column chromatographies. The molecular weights of proteases BK7-1 and BK7-2 determined by gel filtration chromatography were 20,700 and 40,800, respectively. The $K_m$ value, isoelectric point, and optimum pH of protease BK7-1 were 2.55 mg/ml, 11.0 and 11.0, respectively, whereas those of protease BK7-2 were 1.57 mg/ml, 7.2, and 10.0, respectively. Both protease were practically stable in the pH range of 5-11. The optimum temperatures for the activities of both protease BK7-1 and BK7-2 were 50℃ and 45℃, respectively. About 56% of the original protease BK7-2 activity remained after being treated at 50℃ for 30 min but protease BK7-1 was rapidly inactivated at above 25℃. Both proteases were completely inhibited by phenylmethane sulfonyl fluoride, a serine protease inhibitor. Protease BK7-2 was stable against EDTA, EGTA, STP, and detergents such as SDS and LAS, whereas protease BK7-1 was found to be unstable.

Production of Xylooligosaccharides with Thermostable Xylanases from the Streptomyces thermocyaneo-violaceus (내열성 방성균 Streptomyces thermocyaneoviloaceus 의 Xylanases를 이용한 자일로올리고당의 생산)

  • 이오석;최충식;최준호;주길재;이인구
    • Microbiology and Biotechnology Letters
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    • v.29 no.4
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    • pp.221-226
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    • 2001
  • Streptomyces themocyaneovio-laceus producing the thermostable xylanase was used for the production of xylooligosaccharides from xylan. The optimal conditions for the xylanase production were investigated in jar fermentor, which operated at 2 vvm aera-tion and 400 rpm agitation speed at $50^{\circ}C$ for 24 h. The optimal reaction condtion for the production of xylooli-gosaccharides with xylanases which were prepared by the percipitation with ammonium sulfate were obtained by the reaction at $60^{\circ}C$ for 12 h in the mixture composed of 10% birchwood xylan in 50 mM sodium phosphate buffer (pH 6.0)and 10 unit/ml of xylanase. In this optimal condition for the xylooligosaccharides production the mixture of xylooligosaccharides (58.8 g/I) which were composed of 20.1 g/I of xyobiose, 8.9 g/I of xylotriose 4.5 g/I of xylotetraose 16.2g/I of xylopentaose and 9.1 g/I xylohexaose and 5.0 g/I of xylose was produced from 100 g/I of birchwood xylan by the xylanases of S thermocyaneoviolaceus .

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A study on the Rapid Processing of Hydrolyzed Anchovy Paste and Its Quality Stability (효소분해법에 의한 페이스트형 속성 멸치젓의 제조 및 품질에 관한 연구)

  • HAN Bong-Ho;KIM Sang-Ho;CHO Hyun-Duk;CHO Man-Gi;BAE Tae-Jin
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.1
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    • pp.79-87
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    • 1997
  • A study on the processing method of anchovy hydrolysate paste (AHP) was carried out to improve the sensory quality of salted and fermented fish. Homogenized whole anchovy was hydrolyzed using commercial pretenses, Complex enzyme-2000 (CE, Pacific Chem. Co.) and Alcalase (AL, Novo), in a cylindrical vessel with 4 baffle plates and 6-bladed turbine impeller. Optimal pH, temperature, and enzyme concentration for the hydrolysis with CE and AL were $7.0,\;52^{\circ}C,\;7\%$, and $8.0,\;60^{\circ}C,\;6\%$, respectively. The rational amount of water for homogenization, agitation speed, and hydrolyzing time were $100\%\;(w/w)$, 100 rpm, and 210 min, respectively. To make the hydrolysate to paste type, it was effective to mix the additives, such as starch, soybean protein, agar, and carrageenan gum to the hydrolysate 5 min before the end of boiling at $100^{\circ}C$ for 30 min. Minimal NaCl concentration for long-term preservation was $15\%$, and this could be reduced to $12\%$ by adding $5\%$ of KCl. yield of the AHP based on the total nitrogen content was $94.6\~97.0\%,\;and\;86.0\~89.2\%$, of the nitrogen was amino nitrogen. Salinity, pH and histamine content of the AHP prepared with $12\%$ NaCl and $5\%$ KCl were $9.3\~9.9\%,\;6.1\~6.2$, and below 13 mg/100 g, respectively. The AHP was stable at $26{\pm}3^{\circ}C$ for 60 days on bacterial growth, and addition of $0.05\%$ of rosemary (Herbalox) extract was effective to inhibit the lipid oxidation of the AHP during storage.

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Economic Production of $\gamma$-Interferon from Recombinant Human Cells in Serum Free Medium by a Moving Aeration Membrane Bioreactor (교반형 막 반응기를 이용한 재조합 인간 세포의 무혈청 배지에 의한 $\gamma$-Interferon의 생산)

  • Park, Young-Shik;Kim, Hyun-Kyu;Lim, Seo-Kyu;Park, Kyung-You;Lee, Hyeon-Yong
    • Microbiology and Biotechnology Letters
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    • v.22 no.4
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    • pp.389-394
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    • 1994
  • 8 X 10$^{6}$(viable cells/ml) of maximum cell density and 9000(IU/ml) of $\gamma$-IFN production were obtained at 55(ml/hr) of a perfusion rate by cultivating HSF cells using a moving membrane aeration bioreactor. This system proves to be an efficient culture process by maintaning 90% of viable cells during the whole cultivation periods. The metabolic molar quotient of glucose to lactate was 0.81 for overall ranges of glucose consumed while the evolution of ammonia was not linearly related to the consumption of glutamine. Low molar conversion ratio was observed in low consumptions of glutamine and high molar conversion ratio in high comsumptions. It also shows that the glutamolysis plays important role in the steady state conditions by evolving larger quantities of ammonia than lactate. At the above of 50 rpm, which is the optimum agitation speed for this bioreactor, the cell growth was severely affected while the IFN production was less decrea- sed, maintaing 1.5 X 10$^{-3}$(IU/cell/day) specific IFN production rate. The cumulatvie $\gamma$-IFN production was 7.2 X 10$^{8}$(IU) for 70 days of the cultivation, which yields 1 X 10$^{7}$ (IU/day) of IFN production rate. Therefore, a commercial production of $\gamma$-IFN by this culture process can be achievable by maintaining the above IFN productivity in a scaled-up culture system.

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Study on the Production and the Culture Condition of Cholesterol Oxidase from Bacillus megterium SFO41 (Bacillus megaterium SFO41에 의한 Cholesterol Oxidase의 생산 및 최적 배양 조건)

  • 김관필;이창호;우철주;박희동
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.3
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    • pp.403-409
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    • 2001
  • A novel strain of SFO41 producing a large amount of cholesterol oxidase as an extracellular enzyme isolate from Korean salt fermented foods. The strain was identified as Bacillus megaterium based on morphological, cultural and physiological characteristics. Experiments were carried out to optimized the condition of cholesterol oxidase production using B. megaterium SFO41. B. megaterium SFO41 was shown to give the maximum yield of cholesterol oxidase in the medium containing 2.0% glucose, 0.5% yeast extract. 0.03% $MgSO_4{\cdot}7H_2O,\;0.02%\;K_2HPO_4,\;0.2%\;NH_4NO_3$ and 0.2% cholesterol. The optimum culture conditions, temperature, initial pH and agitation speed were $30^{\circ}C$, 7.0 and 150 rpm, respectively. The enzyme production reached a maximum level at 24 hr of cultivation (2.37 U).

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