• Title/Summary/Keyword: new strain

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A new finite element based on the strain approach with transverse shear effect

  • Himeur, Mohammed;Benmarce, Abdelaziz;Guenfoud, Mohamed
    • Structural Engineering and Mechanics
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    • v.49 no.6
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    • pp.793-810
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    • 2014
  • This research work deals with the development of a new Triangular finite element for the linear analysis of plate bending with transverse shear effect. It is developed in perspective to building shell elements. The displacements field of the element has been developed by the use of the strain-based approach and it is based on the assumed independent functions for the various components of strain insofar as it is allowed by the compatibility equations. Its formulation uses also concepts related to the fourth fictitious node, the static condensation and analytic integration. It is based on the assumptions of tick plate.s theory (Reissner-Mindlin theory). The element possesses three essential external degrees of freedom at each of the four nodes and satisfies the exact representation of the rigid body modes of displacements. As a result of this approach, a new bending plate finite element (Pep43) which is competitive, robust and efficient.

Pervaporative Butanol Fermentation Using a New Bacterial Strain

  • Park, Chang-Ho
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.1 no.1
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    • pp.1-8
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    • 1996
  • Fermentation processes for the production of butanol had an economic importance in the first part of this century. Today butanol is commercially produced from the Oxo reaction of propylene because relatively low priced propylene during the cracking of petroleum. Efforts have been made during the past decade or two to improve the productivity of butanol fermentation processes. It includes strain improvements, continuous fermentation processes, cell immobilization and simultaneous product separation. This review introduces a new butanol fermentation process using pervaporative product separation and a new bacterial strain producing less amount of organic acids. This review also compares the new process with chemical processes. This kind of new fermentation process may be able to compete with the chemical synthesis of butanol and revitalize the butanol fermentation process.

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Isolation and Characterization of a New Methanobacterium formicicum KOR-1 from an Anaerobic Digester Using Pig Slurry

  • Battumur, Urantulkhuur;Yoon, Young-Man;Kim, Chang-Hyun
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.4
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    • pp.586-593
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    • 2016
  • A new methanogen was isolated from an anaerobic digester using pig slurry in South Korea. Only one strain, designated KOR-1, was characterized in detail. Cells of KOR-1 were straight or crooked rods, non-motile, 5 to $15{\mu}m$ long and $0.7{\mu}m$ wide. They stained Gram-positive and produced methane from $H_2+CO_2$ and formate. Strain KOR-1 grew optimally at $38^{\circ}C$. The optimum pH for growth was 7.0. The strain grew at 0.5% to 3.0% NaCl, with optimum growth at 2.5% NaCl. The G+C content of genomic DNA of strain KOR-1 was 41 mol%. The strain tolerated ampicillin, penicillin G, kanamycin and streptomycin but tetracycline inhibited cell growth. A large fragment of the 16S rRNA gene (~1,350 bp) was obtained from the isolate and sequenced. Comparison of 16S rRNA genes revealed that strain KOR-1 is related to Methanobacterium formicicum (98%, sequence similarity), Methanobacterium bryantii (95%) and Methanobacterium ivanovii (93%). Phylogenetic analysis of the deduced mcrA gene sequences confirmed the closest relative as based on mcrA gene sequence analysis was Methanobacterium formicicum strain (97% nucleic acid sequence identity). On the basis of physiological and phylogenetic characteristics, strain KOR-1 is proposed as a new strain within the genus Methanobacterium, Methanobacterium formicicum KOR-1.

Growth Optimization of Photorhabdus luminescens Isolated from Entomopathogenic Nematode Heterorhabditis bacteriophora (병원성 선충 Heterorhabditis bacteriophora에서 분리된 공생 박테리아 Photorhabdus luminescens의 생장조건)

  • Yoo, Sun Kyun;Randy Gaugler;Christopher W. Brey
    • Microbiology and Biotechnology Letters
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    • v.29 no.2
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    • pp.104-109
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    • 2001
  • The yield of infective juveniles of Heterorhabditis bacteriophora (Tf strain) in vitro monoxenic liquid culture was improved significantly as the amount of symbiont biomass, Photorhabdus sp. strain Tf, increased. To investigate the influence of abiotic factors on the growth and biomass production of Photorhabdus sp. strain Tf, triplicate flask cu1tmes were performed. The optinal temperature and medium pH for the growth of Photorhahdus sp. strain Tf were 30$^{\circ}$C and between pH 5.5-7.3, respectively. Aeration also improved greatly growth and yield of biomass of Photorhabdus sp. strain Tf. Photorhabdus sp. strain Tf in batch fermentation showed growth-associated pattem in terms of pigment production, and the pH of culture medium rose steadily until growth stopped dUling the fermentation. Both pigment production and culture pH rise would be useful parameters indicating a reliable growth of Photorhabdus sp. strain Tf.

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A Gram-negative halophilic carotenoid-producing bacterium, Paracoccus sp.

  • Lee, Jae-Hyung;Lee, Won-Jae;Kim, Young-Tae
    • 한국생물공학회:학술대회논문집
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    • 2003.04a
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    • pp.710-712
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    • 2003
  • A new species of Gram-negative halophilic cartenoid producing bacterium was isolated from the Haeundae Coast, Korea. This strain is non-motile, aerobic, orange-pigmented, rod-shaped, and produced carotenoids, mainly astaxanthin. All the type strains of the genus Paracoccus were compared with this strain using 16S rDNA sequence analysis, fatty acid patterns, and physiological reaction profiles. From the results obtained, this strain is classified as a new species, Paracoccus sp..

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Studies on the Amylase Producing Bacteria. (partI) (Amylase 생성세균에 관한 연구 1)

  • 이석건;이한창
    • Korean Journal of Microbiology
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    • v.2 no.1
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    • pp.19-24
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    • 1964
  • 1. Three hundred and twenty four strains of amylase producing bacteria were isolated from various sources and a high amylase producing new strain, which was isolated from MEJU, M-181, was selected for further investigations. 2. The new strain M-181 was similar to Bacillus subtilis in the characteristics. 3. Wheat bran medium was the best one for production of amylase so for as the investigations had been done. The amylase activity of M-181 was measured D$40^{\circ}\\30^{'}$ .$deg._{30'}$ 25,000 to 26,800 on the medium of wheat bran. 4. The strain M-181 did not demand phosphate for production of amylase.

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Breeding of a Recessive Soybean Genotype (titirs2rs2) with Green Cotyledons and Black Seed Coats (titirs2rs2 열성 유전자형을 가진 속푸른 검정콩 계통 육성)

  • Choi, Sang Woo;Kim, Jin A;Shim, Sang In;Kim, Min Chul;Chung, Jong Il
    • Journal of Life Science
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    • v.29 no.2
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    • pp.147-151
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    • 2019
  • Soybean [Glycine max (L.) Merr.] is grown worldwide for its high protein and oil content. Anthocyanins from black soybean seed coats are known to have many pharmaceutical effects. Soybean cultivars with large seed sizes and black seed coats are needed by soybean farmers. However, antinutritional factors, like protein, stachyose, and Kunitz trypsin inhibitor (KTI) exist in raw mature soybeans. Genetic elimination or reduction of these components is needed in soybean breeding. The objective of this research was to develop new a soybean strain with black seed coats and green cotyledons that was KTI protein free and low in stachyose. Six parents were used. The presence or absence of KTI protein was detected using the Western blot technique. The content of stachyose in mature seeds was detected using HPLC. One new strain was selected from 11 $F_2$ plants with black seed coats and green cotyledons that lacked KTI protein. The new strain had black seed coats and green cotyledons and was KTI protein free and low in stachyose. The plant height of the new strain was 66 cm, and its 100-seed weight was 28.4 g. The stachyose content of the new strain was 2.59 g/kg. The new strain developed in this research will be used to develop new cultivars that are KTI protein free and low in stachyose.

Characterization of a New Acidophilic Acetobacter sp. Strain HA Isolated from Korean Traditional Fermented Vinegar

  • CHUN, HONG-SUNG;SUNG-JUN KIM
    • Journal of Microbiology and Biotechnology
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    • v.3 no.2
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    • pp.108-114
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    • 1993
  • A new strain of acidophilic, acetogenic bacterium, Acetobacter sp. strain HA was isolated by selective enrichment from the traditionally fermented rice wine vinegar in Korea. It was a gram-negative, non-motile short rod and oxidized acetate and lactate. The optimal temperature and pH for growth were $28^{\circ}C$ and 4.0, respectively. The strain HA differed from other Acetobacter species by growing well on methanol, xylitol, inositol, dulcitol, D-xylose, L-arabinose, and D-mannose as sole sources of carbon and energy. The isolated strain HA did not produce $\gamma$-pyrones from glucose and did not produce ketone bodies from glycerol. The quinone system used in this study was an ubiquinone-9 isoprene unit. The guanine-plus-cytosine content of the DNA was 50.7 mol%, and the major cellular fatty acids were $C_{18:1} and C_{16:0}$.

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Identification of Prevotella intermedia ATCC 25611 Using Pi29-L DNA Probe. (Pi29-L DNA 프로브를 이용한 Prevotella intermedia ATCC 25611의 동정)

  • 국중기;백동헌
    • Microbiology and Biotechnology Letters
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    • v.31 no.2
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    • pp.205-209
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    • 2003
  • Recently, we introduced a new method for rapid screening of bacterial species- or subspecies-specific DNA probes, named “inverted dot blot hybridization screening method”. We then applied this method to develop species- or strain- specific DNA probes for Prevotella intermedia and Prevotella nigrescens. In those studies, among 96 candidate DNA probes which were screened by the new method, 5 probes were confirmed as being putatively strain-specific : 3 probes for P. nigrescens 9336 (ATCC 33563), one for each p. intermedia ATCC 25611 and one for P. nigrescens G8-9K-3 (ATCC 49046). In the present study, we evaluated by Southern blot analysis a DNA probe Pi29-L, one of the 96 candidate probes described above, whether it is specific for the strain ATCC 25611 off. intermedia. Our data show that the probe Pi29-L is potentially P. intermedia ATCC 25611-specific, which can be useful for the detection and identification of the strain, particularly in maintenance of the strain.

Evaluation of Sample Quality for Marine Clay by Large Block Samples (대형블럭시료를 이용한 해성점토 시료의 품질 평가)

  • Kim, Jong-Kook;Yoon, Won-Sub;Kim, Ji-Hee;Chae, Young-Soo
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.03a
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    • pp.1004-1011
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    • 2008
  • In this study, obtained large block sample and piston sample of marine clay in korea were performed unconfined compression and consolidation test. Soil properties of two type samples such as failure strain, between two parameter's ratio($E_{50}$ and $q_u$), and volumetric strain were used to evaluate sample disturbance. The result, large block samples show a low disturbance than piston samples. Therefore, we suggest new sample disturbance evaluated method through the relation of OCR and volumaric strain at shallow of marine clay in Korea and suggest new sample disturbance classified method by subdivided grade for failure strain of unconfined compression test.

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