• Title/Summary/Keyword: bio materials

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Menthol biosynthesis pathway in Mentha piperita suspension cells (박하(Mentha piperita) 세포 현탁배양에서 멘톨생합성 경로)

  • Park, Si-Hyung;Chae, Young-Am;Lee, Hyong-Joo;Kim, Soo-Un
    • Applied Biological Chemistry
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    • v.36 no.5
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    • pp.358-363
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    • 1993
  • The metabolic capability of the cultured cells of peppermint was tested with whole intact cells by feeding appropriate exogenous substrates to the suspension cultures. Conversion of (-)-limonene into any other monoterpenes was not observed with the suspension cultures. (+)-Pulegone was converted into (+)-isomenthone and (-)-menthone, and (-)-menthone into (-)-menthol. The experiments confirmed that the suspension retained most of the menthol biosynthesis pathway in the cell except for a few loci. (-)-Isopiperitenone was transformed into (+)-pulegone, piperitenone, (-)-7-hydroxyisopiperitenone and two unidentified products.

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Expression of Bacillus macerans Cyclodextrin Glucanotransferase in Bacillus subtilis

  • Kim, Chang-Sup;Han, Nam-Soo;Kweon, Dae-Hyuk;Seo, Jin-Ho
    • Journal of Microbiology and Biotechnology
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    • v.9 no.2
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    • pp.230-233
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    • 1999
  • A plasmid vector was constructed for the expression and secretion of Bacillus macerans cyclodextrin glucanotransferase (CGTase) in Bacillus subtilis. The vector, pUBACGT, was composed of the ribosome-binding sequence, signal sequence, and cgt gene from B. macerans under the control of amyR2, the promoter of amyE gene coding for $\alpha$-amylase from B. subtilis var. natto. Bacillus subtilis LKS88, a mutant strain lacking genes for an amylase and two proteases, was used as a host for the transformation of the plasmid vector. The transformants were selected on kanamycin-containing Luria-Bertani plates. The starch hydrolyzing activity was observed on the starch-containing plates by the iodine method and cyclodextrin-forming activity was detected in the culture medium. A SDS-PAGE analysis showed that most of the expressed CGTase in the recombinant B. subtilis was secreted into the medium at a high expression level.

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Synthesis of anisotropic defective polyaniline/silver nanocomposites

  • Kamblea, Vaishali;Kodwania, Gunjan;Sridharkrishna, Ramdoss;Ankamwar, Balaprasad
    • Advances in nano research
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    • v.2 no.2
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    • pp.111-119
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    • 2014
  • The chemical synthesis of anisotropic defective polyaniline/Ag composite (PANI/Ag) is explored using silver nitrate ($AgNO_3$) as the precursor material. This study provides a simple method for the formation of PANI/Ag nanocomposites at two different aniline concentrations $5{\mu}l$ (PANC5) and $10{\mu}l$ (PANC10). The composite PANC5 exhibits UV-Visible absorption peaks at 436 nm and 670 nm whereas, PANC10 exhibits absorption peaks at 446 nm and 697 nm. This shift is caused by the strong interaction between polyaniline and silver. The characterized FTIR peaks observed at around $3410cm^{-1}$ (PANC5) and $3420cm^{-1}$ (PANC10) was due to the N-H stretching vibrations. The appearance of a broad band instead of a sharp peak can be attributed due to the presence of a high concentration of N-H groups in the nanocomposite. The TEM images show that the sample contains defective spherical, truncated triangular and rod shaped particles. The results showed that the PANI/Ag nanocomposites are composed of nano-sized particles of 43-53 nm that contain Ag domains of 33-37 nm with polymer thickness 5.7-11.2 nm at two different aniline concentrations.

A Study on Heat Transfer of Plywood for Wood Based Flooring by Veneer Composition (마루판용 합판의 단판 구성요소에 따른 열전달 특성에 관한 연구)

  • Pi, Duck-Won;Choi, Song-Kyu;Kang, Ho-Yang;Kang, Seog-Goo
    • Journal of the Korea Furniture Society
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    • v.23 no.3
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    • pp.298-304
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    • 2012
  • Since 1990's, a flooring based on plywood has gotten customers' demand. Costs of raw material and production increased because of changed environment of industry. Tropical timber such as Red Meranti (Shorea acuminate) used for raw material of the floor has been depleting beside countries in South Eastern Asia changed species of afforestation. As a result, it gets hard to secure good quality of raw material for plywood. Moreover plywood price is increased suddenly after earthquake in Japan. Eucalyptus (Eucalyptus globulus) in china has been using for raw material as a countermeasure of changed environment of industry. In this study, possibility of using flooring consisted of Eucalyptus veneer as a core layer was checked by heat transfer experiments. Flooring consisted of Red Meranti was used for comparison. Two factors which impact on heat transfer are a type of density gradient and density difference between Long-grain veneer and Short-grain veneer. Red Meranti samples are 'M' type of density gradient on the other hand Eucalyptus samples are 'W' type of density gradient.

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Effects of Incubation Temperature on Egg Development, Hatching and Pigment Plug Evacuation in Farmed Siberian Sturgeon Acipenser baerii

  • Park, Chulhong;Lee, Sang Yoon;Kim, Dong Soo;Nam, Yoon Kwon
    • Fisheries and Aquatic Sciences
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    • v.16 no.1
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    • pp.25-34
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    • 2013
  • Early ontogenic development in Siberian sturgeon Acipenser baerii was documented and the effects of different temperatures on embryonic and prelarval development were examined. Photograph-assisted data on morphogenesis in Siberian sturgeon prolarvae agreed well with published descriptions of their ontogeny and ecological behaviors, although certain aspects of differentiation, such as gill covering and scute development, could be rearing condition-sensitive. The present study provides the first characterization of the transient development of teeth during early larval stages; the pattern was congruent with the transition of prolarvae to exogenous feeding. From examinations of embryonic and prelarval development under different temperature conditions ($12-24^{\circ}C$), developmental speed was inversely related with temperature. Overall, hatchability was higher and hatching events were more synchronized at $20^{\circ}C$ than at lower temperatures. After hatching, similar patterns of temperature-dependency were observed in yolk sac absorption and the evacuation of the pigment plug. Our results suggest that the incubation of Siberian sturgeon embryos and prolarvae at temperatures close to $20^{\circ}C$ would be advantageous in hatcheries, based on reductions in the duration and uniformity of egg and prolarval developmental stages.

Embryonic Development of Siberian Sturgeon Acipenser baerii under Hatchery Conditions: An Image Guide with Embryological Descriptions

  • Park, Chulhong;Lee, Sang Yoon;Kim, Dong Soo;Nam, Yoon Kwon
    • Fisheries and Aquatic Sciences
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    • v.16 no.1
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    • pp.15-23
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    • 2013
  • Normal embryonic development at a constant temperature ($18^{\circ}C$) has been described for the Siberian sturgeon Acipenser baerii (Acipenseriformes). Hormone-induced spawning and artificial insemination were performed to prepare embryonic batches for embryologic examination. After insemination, early cleavages of the Siberian sturgeon embryos continued for 7 h post-fertilization (HPF), showing the typical pattern of uneven holoblastic cleavage. Blastulation and gastrulation began at 9 HPF and 19 HPF, respectively. Epiboly formation (2/3 covered) was observed at 25 HPF during gastrulation. Neurulation was initiated with the formation of a slit-like neural groove from the blastopore at 33 HPF. During neurulation, the primary embryonic kidney (pronephros) and s-shaped heart developed. The embryos underwent progressive differentiation, which is typical of Acipenseriform species. A mass hatching was observed at 130 HPF, and the average total length of the hatched prolarvae was 10.5 mm. The hatched prolarvae possessed a typical pigment plug (yolk plug). The results of this study are valuable not only as a reference guide for the artificial propagation of Siberian sturgeon in hatcheries but also as the basis for the derivation of developmental gene expression assays for this species.

Bio-polishing and Silket Treatment of Cotton Yarns (면사의 효소가공 및 실켓 가공)

  • Bae, Young-Hwan;Lee, Ji-Wan;Son, Young-A;Kim, Ju-Hae;Kwon, Mi-Yeon;Kim, Eui-Hwa;Lee, Seung-Goo
    • Textile Coloration and Finishing
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    • v.20 no.4
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    • pp.15-20
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    • 2008
  • The cotton yarn was subjected to bio-polishing treatment with three commercial enzymes(Cellusoft L, Denimax-991L and Denimax-acid) to remove the fuzz on the cotton yarn. Also, enzyme treated cotton yarns were compared with singeing cotton yarns. Experimental variables of enzyme treated cotton yarn were as follow: concentration of enzyme solution and NaOH, dipping time, and processing temperature. The enzymatic treatments were evaluated by analyzing the effect on yarn count, twist contraction, evenness and tenacity. As the results, enzymatic treatment on cotton yarn induced same effects as the traditional singeing treatment. Also, silket treatment of cotton yarn after bio-polishing enhanced the tensile properties of the cotton yarn.

Bio-fusion and Medical Device Industry (바이오융합 및 의료기기 산업)

  • Park, Su A;Lee, Jun Hee;Kim, Wan Doo
    • Transactions of the KSME C: Technology and Education
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    • v.5 no.1
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    • pp.23-52
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    • 2017
  • Bio-fusion and medical device industry is the multidisciplinary engineering application technology industries, which are fused, such as electricity, electronics, machinery, materials. It aims to improve the quality of human life by using bio-fusion and medical devices, and is an important industry recognition and brand power for the product. However, there is a period that is required from the development of products with technology-dependent industries. Therefore, it is necessary to have continuous effort for industrial investment in research and development at the national level including technical support, institutional support, and human resources.

Coating Effect of Low Temperature Melting Bi-Sn Metalized Wood Composites on 10 Different Korean Wood Species (주요 국산재 10가지 수종에 대한 Bi-Sn 저온용융 합금주입 목재복합체의 도장 효과)

  • Park, Kye-Shin;Seo, In Soo;Lee, Hwa Hyoung;Kang, Seog Goo
    • Journal of the Korea Furniture Society
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    • v.25 no.3
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    • pp.223-232
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    • 2014
  • To make metalized wood composites of 10 different korean wood species, it was tested by Low temperature melting Bi-Sn alloy injection method at high temperature and high pressure condition. Metalized wood composite of each wood species had light ash color, but still maintained its own natural wood grain and wood figures. It was evaluated on coating properties. Furthermore, it also was check on effect of coating as like a changes of main color, wood grain and wood figures. The results of test were following as; a coating properties as like a cold resistance, heat resistance, acid resistance, alkali resistance, durability of abrasion, and cross-cut test was proper on the conditions of the KS standard. And, In aspect of color changes, the metalized wood composites of 10 different korean wood species had a light ash color, but still maintained its own natural wood grain and wood figures. Also, the more weight per gain of alloy is, the more grey background of metalized wood composite is.

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Quantification of Inulo-oligosaccharides Using High pH Anion Exchange Chromatography with Pulsed Amperometric Detector (HPAEC-PAD)

  • Kang, Su-Il;Chang, Yung-Jin;Kim, Kyoung-Yun;Kim, Su-Il
    • Journal of Applied Biological Chemistry
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    • v.42 no.4
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    • pp.166-168
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    • 1999
  • Inulo-oligosaccharides (IOS, $F_n$, n=2-6) were purified from enzymatic hydrolysates of water-soluble extract of Jerusalem artichoke tubers. Quantification of inulo-oligosaccharides was done using high pH anion exchange chromatography with pulsed amperometric detector (HPAEC-PAD) at the concentration range of 10-100 mg/L, which was compared with that of fructo-oligosaccharides (FOS, $GF_n$, n=1-7). Peak areas per mg IOS were higher than FOS at the same degree of polymerization (DP). Specific peak areas of IOS increased proportionally as DP increased up to six, in contrast to FOS showing no linearity.

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