• Title/Summary/Keyword: Biological Engineering

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Red Pigment Producing Serratia marcescens Isolated from Abalone (Haliotis discus) (전복(Haliotis discus)에서 분리한 Serratia marcescens가 생산하는 적색 색소의 항균활성)

  • Shin, YuJin;Kang, Chang-Ho;So, Jae-Seong
    • KSBB Journal
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    • v.31 no.4
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    • pp.214-218
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    • 2016
  • Serratia marcescens characterized by the ability to produce red pigments inhabits various ecological niches. A strain Serratia marcescens PYU was isolated from abalone (Haliotis discus) collected at the West Sea in Korea. The isolated strain was gram-negative, motile, rods like coccus, oxidase-negative, and catalase-positive; and formed red pigment. S. marcescens PYU was grown in the presence of 0~10% (w/v) NaCl, at pH 4~9, and at $10{\sim}40^{\circ}C$. The strain PYU produced red pigment, and the extracted pigment showed antibacterial activity against Streptococcus iniae and Lactococcus garviae which has been known as an important fish pathogens. Further studies are underway to elucidate the direct relationship between the red pigment and antibacterial activity.

A Facile and Efficient Synthesis of Dronedarone Hydrochloride

  • Li, Feng;Jin, Chunhua;Zou, Jianwei;Wu, Jun
    • Bulletin of the Korean Chemical Society
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    • v.35 no.7
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    • pp.1970-1972
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    • 2014
  • A facile and efficient synthesis of dronedarone hydrochloride starting from commercially available 4-nitrophenol is described. This approach features a tandem-type synthesis of 3-carbonylated benzofuran involving cyclization of 2-ethynylphenol followed by $CO_2$ fixation at the 3-position of the benzofuran ring mediated by potassium carbonate without the addition of any transition metal catalyst.

Sophorolipid Production by Candida bombicola ATCC 22214 from a Corn-Oil Processing Byproduct

  • KIM , HYUN-SOO;KIM, YOUNG-BUM;LEE, BAEK-SEOK;KIM, EUN-KI
    • Journal of Microbiology and Biotechnology
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    • v.15 no.1
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    • pp.55-58
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    • 2005
  • Sophorolipid was produced by Candida bombicola ATCC 22214 from soybean dark oil, a byproduct of soybean oil processing. With a fed-batch culture of C. bombicola for 7 days, 90 g/l of sophorolipid was obtained. The CMC (critical micelle concentration) and minimum surface tension of the sophorolipid in aqueous solution were found to be 150 mg/l and 48 mN/m, respectively. The dispersion capability of sophorolipid was higher than that of the chemical surfactants such as SDS and Brij30. The molar solubility ratio (MSR) of 4-methylnaphthalene was 0.2. Linoleic and oleic acids were the main constituents of the fatty acid composition of the sophorolipid. The sophorolipid showed antimicrobial activity against Propionibacterium acne and Bacillus subtilis.

Hydrolysis of Olive Oil by Lipase, Immobilized on Hydrophobic Support

  • Jung, Ju-Young;Yun, Hyun-Shik;Kim, Eun-Ki
    • Journal of Microbiology and Biotechnology
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    • v.7 no.2
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    • pp.151-156
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    • 1997
  • Two commercially available lipases, Lipase OF (non-specific lipase from Candida rugosa) and Lipolase 100T (1, 3-specific lipase from Aspergillus niger), were immobilized on insoluble hydrophobic support HDPE (high density polyethylene) by the physical adsorption method. Hydrolysis performance was enhanced by mixing a non-specific Lipase OF and a 1, 3-specific Lipolase 100T at a 2 : 1 ratio. The results also showed that the immobilized lipase maintained its activity at broader temperature ($25~55^{\circ}C$) and pH (4-8) ranges than soluble lipases. In the presence of organic solvent (isooctane), the immobilized lipase retained most of its activity in upto 12 runs of hydrolysis experiment. However, without organic solvent in the reaction mixture, the immobilized lipase maintained most of its activity even after 20 runs of hydrolysis experiment.

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Effects of the Hovenia dulcis THUMBER var. Koreana Nakai Extracts on Hepatoprotective Activities and Improvement of Hepatofunction

  • Hwang Hyun-Ik;Lee In-Soon;Chae Hee-Jun;Moon Hae-Yeon
    • Biomedical Science Letters
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    • v.11 no.2
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    • pp.237-242
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    • 2005
  • The Hovenia extracts showed a significant hepato-protective activity against alcohol and CC4-induced hepatotoxicity. Injection of CC4 and alcohol induced liver injury and increased serum GOT (glutamic oxaloacetic transaminase) and GPT (glutamic pyuvic transaminase) levels in injured rats. The ADH (alcohol dehydrogenase)-like and ALDH (aldehyde dehydrogenase)-like activities in the Hovenia extracts were studied. Their activities in the extracts of Hovenia wood were higher than the extracts of other parts of Hovenia. And then Hovenia wood extracts have high effects on the alcohol and acetealdehyde degradation. The Hovenia extracts were decreased concentration of fusel oil. The ADH-like and ALDH-like activities in the Hovenia wood extract were 1.14 $unit/{\mu}l$, 0.33$unit/{\mu}l$ respectively.

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Proteomics-Driven Identification of SCO4677-Dependent Proteins in Streptomyces lividans and Streptomyces coelicolor

  • Choi, Si-Sun;Kim, Seon-Hye;Kim, Eung-Soo
    • Journal of Microbiology and Biotechnology
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    • v.20 no.3
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    • pp.480-484
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    • 2010
  • AfsR2 is a global regulatory protein that stimulates antibiotic biosynthesis in both Streptomyces lividans and S. coelicolor. Previously, various afsR2-dependent genes including a putative abaA-like regulatory gene, SCO4677, were identified through comparative DNA microarray analysis. To further identify the putative SCO4677-dependent proteins, the comparative proteomics-driven approach was applied to the SCO4677-overexpressing strains of S. lividans and S. coelicolor along with the wild-type strains. The 2D gel electrophoresis gave approximately 277 protein spots for S. lividans and 207 protein spots for S. coelicolor, showing different protein expression patterns between the SCO4677-overexpressing strains and the wild-type strains. Further MALDI-TOF analysis revealed that only 18 proteins exhibited similar expression patterns in both S. lividans and S. coelicolor, suggesting that the SCO4677 could encode an abaA-like regulator that controls a few cross-species common proteins as well as many species-specific proteins in Streptomyces species.

LOAD CHARACTERISTICS OF ROTARY OPERATION BY TRACTOR IN WET PADDY FIELDS

  • Y. G. Wu;Kim, K. U.;Y. K. Jung
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 2000.11b
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    • pp.101-108
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    • 2000
  • The torque loads were measured at the input shaft of the transmission and driving shaft of the tractor having a cage wheel attached to the driving tires as a traction aid during. a rotavating operation in wet paddy fields with deep hardpan. Their load spectra were also calculated. Effects of design parameters of the cage wheel on the load characteristics were analyzed. The torque load exerted on the input shaft decreased as diameter of the cage wheel increased and increased as the rotating speed of the rotavator increased. The torque load exerted on the driving shaft increased as the working speed of the tractor increased and decreased as the PTO speed increased. Both the torque loads with the cage wheel were greater than those without the cage wheel. The cage wheel was developed for this study.

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DEVELOPMENT OF A 3-DOF ROBOT FOR HARVESTING LETTUCE USING MACHINE: VISION AND FUZZY LOGIC CONTROL

  • S. I. Cho;S. J. Chang;Kim, Y. Y.
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 2000.11b
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    • pp.354-362
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    • 2000
  • In Korea, researches on year-round leaf vegetables production system are in progress, most of them focused on environmental control. Therefore, automation technologies for harvesting, transporting, and grading are in great demand. A robot system for harvesting lettuces, composed of a 3-DOF (degree of freedom) manipulator, an end-effector, a lettuce feeding conveyor, an air blower, a machine vision system, six photoelectric sensors, and a fuzzy logic controller, was developed. A fuzzy logic control was applied to determine appropriate grip force on lettuce. Leaf area index and height were used as input variables and voltage as an output variable for the fuzzy logic controller. Success rate of the lettuce harvesting was 94.12%, and average harvesting time was approximately 5 seconds per lettuce.

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Characteristics of transmission efficiency in power driveline of agricultural tractors

  • I. H. Ryu;Kim, D. C.;Kim, K. U.
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 2000.11b
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    • pp.132-138
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    • 2000
  • Complex gear shifting and high speed-reduction ratio reduce the transmission efficiency in power driveline of agricultural tractors. According to a field test, the power transmission efficiency of a tractor in transporting operations was estimated about 70%. However, the actual efficiency was found by the experiment to fluctuate in a range of 56 to 87%. Therefore, the constant efficiency model commonly used for a simulation of power drivelines is not likely to simulate its performance more accurately. In order to predict power transmission efficiency more accurately, a new model was proposed and the new concepts of the maximum efficiency and sticking torque were introduced. The error mean between the measured and the predicted efficiencies was about 2.3% in mean. The new model reflecting the transmission characteristics in the power driveline of tractors could be used to analyze and predict the power transmission performance of tractors more accurately.

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