• Title/Summary/Keyword: isolation source

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Utilization of Crawfish Processing Wastes as Carotenoids, Chitin, and Chitosan Sources (캐로티노이드 , 키틴, 키토산의 원료로서 Crawfish 가공 폐기물의 이용)

  • No, hong-Hyoon;Samuel P.Meyers
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.21 no.3
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    • pp.319-326
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    • 1992
  • The Louisiana crawfish industry comprises the largest concentration of crustacean aquaculture in the United States. Processing plants throughout the culture region annually generate as much as 80 million pounds of peeling waste during recovery of the 15% (by weight) edible tail meat. A commercial oil extraction process for recovery of carotenoid astaxanthin from crawfish waste has been developed. Crawfish pigment in its various forms finds applications as a source of red intensifying agents for use in aquaculture and poultry industries. Crawfish shell, separated in the initial pigment extraction step, is an excellent source of chitin. Applicable physicochemical procedures for isolation of chitin from crawfish shell and its conversion to chitosan have been developed. Crawfish chitosan has been demonstrated to be both an effective coagulant and ligand-exchange column material , respectively, for recovery of valuable organic compounds from seafood processing wastewater.

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A Study on New High Density DRAM Cell (고밀도 DRAM Cell의 새로운 구조에 관한 연구)

  • Yi, Cheon-Hee
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.26 no.6
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    • pp.124-130
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    • 1989
  • For the higher density DRAM'S, innovations in fabrication process and circuit design which have led to dramatic density improvement are discussed from the desinger's perspective. A new dynamic RAM cell called Trench Epitaxial Transistor Cell(TETC) using trench technics and SEG have been developed for use in future megabit DRAMS. Storge electrode with $n^+$-polysilicon and $n^+$-source electrode are self-contacted in TETC. With keeping the storage capacitance large enough to prevent soft errors, the cell size reduced to 30% compare with existing BSE cell by utilizing the vertical capacitor made along the isolation region.

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Isolation of Hafnia Species from Kimchi

  • Kwon, Eun-Ah;Kim, Myung-Hee
    • Journal of Microbiology and Biotechnology
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    • v.19 no.1
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    • pp.78-82
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    • 2009
  • Eight commercially packaged kimchi products were examined over 15 days of storage at $4^{\circ}C$ to evaluate the occurrence of Hafnia alvei (H. alvei). Additionally, 7 saeujeot products, as a possible ingredient source, were analyzed to examine the bacteria's origin. Over the storage period, kimchi samples had decreasing pH levels, which stabilized at pH 4.2; acidity increased to $0.9{\pm}0.1%$. Lactose-nonfermenting bacteria, which H. alvei belongs to, gradually reduced in numbers over the kimchi storage. However, the relative frequency of H. alvei to lactose-nonfermenting bacteria tended to increase. From the kimchi samples, 58 H. alvei-presumptive colonies were selected. Forty three colonies turned out to be H. alvei and 15 colonies were identified as other strains or uncertain identifications when the API 20E system was used. From further test, 3 of the 43 colonies were H. alvei (-) against the phage test. Finally, H. alvei was isolated from saeujeot, indicating that this ingredient can be an originating source of H. alvei in kimchi.

Isolation and Characterization of Cyclohexanol-utilizing Bacteria (Cyclohexanol 이용성 세균의 분리 및 특성)

  • 김태강;이인구
    • Microbiology and Biotechnology Letters
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    • v.27 no.2
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    • pp.107-112
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    • 1999
  • A bacterium, which can utilize cyclohexanol as a sole source of carbon and energy, was isolated from sludge in sewage of Ulsan Industrial Complex for Petrochemicals, Korea and identified as Rhodococcus sp. TK6. The growth conditions of the bacteria were investigated in cyclohexanol containing media. The bacteria utilized cyclohexanol, cyclohexanone, cyclohexane-1,2=diol, cyclopentanol, cyclopentanone, and $\varepsilon$-caprolactone but not cyclohexane, cyclohexane-1,2-dione, and cyclooctanone. The bacteria were able to utilize alcohols such as ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 2-methyl-1-propanol, 3-methyl-1-butanol, 2-propanol, and 2-butanol as well as cyclohexanol, organic acids such as adipate, propionate, butyrate, valerate, n-caproate, and 6-hydroxycaproate, and aromatic compounds such as phenol, salicylate, p-hydroxbenzoate, and benzoate as a sole source of carbon and energy. Cyclohexanone as a degradation product of cyclohexanol by Rhodococcus sp. TK6 was determined with gas chromatography.

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Identification of Noise Source from Main Steam Line in Power Plant (발전소 주증기 배관 소음 발생 원인 규명)

  • Sohn, M.S.;Lee, J.S.;Lee, S.K.;Lee, W.R.;Lee, S.K.
    • Journal of Power System Engineering
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    • v.7 no.3
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    • pp.23-28
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    • 2003
  • In heavy nuclear power plant, high energy through main steam line is provided to turbine that generate the electric power. Since plant had generated power, high noise has been occurred. Noise make equipments and work environment worse. For finding out the location and the cause of making noise, noise was measured along main steam line at open/close test of Main Steam Isolation Valve (MSIV hereafter). As the result, it was identified that the vortex shedding in the cavity of MSIV is main noise source. The profile change of MSIV seat ring was proposed as the method of noise reduction. After filletting MSIV seat ring, the noise level reduced $10{\sim}20dB$ compared before the change of profile.

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Phytochemical Constituents of the Leaves of Hosta longipes

  • Kim, Chung Sub;Kim, Ki Hyun;Lee, Kang Ro
    • Natural Product Sciences
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    • v.20 no.2
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    • pp.86-90
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    • 2014
  • Phytochemical investigation of the 80% MeOH extract from the leaves of Hosta longipes resulted in the isolation of sixteen compounds (1 - 16). The structures of the compounds were elucidated by spectroscopic methods to be methyl 10,10-dimethoxydecanoate (1), methyl 10-hydroxy-8E,12Z-octadecadienoate (2), methyl coriolate (3), trans-phytol (4), phytene-1,2-diol (5), phyton (6), (3S,5R,6S,7E,9R)-7-megastigmene-3,6,9-triol (7), (3S,5R,6S,9R)-3,6,9-trihydroxymegastigman-7-ene (8), shikimic acid (9), p-coumaramide (10), trans-N-p-coumaroyltyramine (11), cis-N-coumaroyltyramine (12), tryptophan (13), thymidine (14), adenosine (15), and deoxyadenosine (16). Compound 1 was synthesized, but not yet isolated from natural source, and compounds 2-16 were isolated for the first time from this plant source.

The Analysis of Perceptual Levels For Floor Impact Noises in Apartments (공동주택에서의 바닥충격음 인지도 분석)

  • 김경호;전진용
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.05a
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    • pp.598-603
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    • 2002
  • The floor impact noise in apartment buildings has been known as the most sensitively recognized environmental noise. Therefore. inhabitants perceptual evaluation of floor impact noises was investigated by a questionnaire survey. It was found that the respondents perceive the floor impact noises from the upper nor as a constant noise level. However, if there is any child on the upper floor. the respondents felt Its noise as a harshly grating level. It was also found that the larger the respondents house is. the higher their wanted level of noise isolation is. Moreover, it was revealed that the main source of the floor impact noise from the upper floor is a child at the age from six to seven. The results could be used as fundamental data for the research on impact sources and new regulations that fit to Korean perceptual aspects and characteristics.

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Isolation of Clostridium thermocellum Producing High Activity of Cellulase (Cellulase의 생산력이 뛰어난 Clostridium thermocellum의 분리)

  • 이호섭;최병일;이용현;박용복;하지홍
    • Korean Journal of Microbiology
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    • v.29 no.3
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    • pp.184-188
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    • 1991
  • Three strains of Clostridium thermocellum, JH01, JH20 and JH30 which are capable of producing ethanol directly from cellulose were isolated from composts. The morphological, cultural and physiological properties of the strains were similar to the ATCC type strain, except for carbon source utilization and degree of ethanol tolerance. All of the three isolates could use glucose and maltose as a sole carbon source and two of them, strains of JH01 and JH20 were three times more tolerant to ethanol than the ATCC type strain. Cellulases secreted by the isolated strains had higher activities than those of the ATCC type strain.

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Isolation and Identification of Trichoderma sp. HK 47 Producing Avicelase (Avicelase 생산성 Trichoderma sp. HK 47의 분리 및 동정)

  • 박헌국;이계호
    • The Korean Journal of Food And Nutrition
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    • v.6 no.3
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    • pp.199-207
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    • 1993
  • In order to obtain a good microorganism capable of degrading microcrystaline cellulose (avicel), the screening test was carried out from soil and brown-rot wood. 8 strains which had good avicel-hydrolyzing activity were isolated. Among them, HK 47 which exhibited the highest avicel hydrolyzing activity was identified as Trichoderma sp. HK 47. Maximum avicel-hydrolyzing enzyme production from Trichoderma sp. HK 47 was obtained with the optimum medium contained carboxymethylcellulose 1.5% as carbon source, NaN030.75% as nitrogen source, KH2P040.5%, MgSO4.7H2O 0.1%, Tween 800.005% (V/V) during stationary cultivation at pH 6.0, 3$0^{\circ}C$ In this case, the production of avicel-hydrolyzing enzyme was 0.028 U/ml.

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Isolation and Characterization of Aerobic Trichloroethylene Cometabolizing Bacterium (호기적 Trichloroethylene 공동대사 세균의 분리 및 특성)

  • 김호성;박근태;손홍주;박성훈;이상준
    • Journal of Environmental Science International
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    • v.10 no.2
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    • pp.99-103
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    • 2001
  • Several microorganisms which degrade phenol and trichloroethylene(TCE) were isolated from the activated sludge of a wastewater treatment plant. Among them, one isolate EL-04J showed the highest degradability and was identified as a Pseudomonas species according to morphological, cultural and biochemical properties. The phenol-induced cells of Pseudomonas EL-04J, which were preincubated in the mineral salts medium containing phenol as a sole carbon source, degraded 90% of 25$\mu$M TCE within 20h. This strain could also utilize some of methylated phenol derivatives (o-cresol, m-cresol and p-cresol) as the sole source of carbon and energy. Cresol-induced cells of Pseudomonas EL-04J also cometabolized TCE.

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