• Title/Summary/Keyword: bio materials

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Effects of Substitutions of Gln16 and Asp18 with Phe or Tyr in HP(2-20) on its Structure and Antimicrobial Activity

  • Kim, Jin-Kyoung;Lee, Ju-Un;Kim, Woong-Hee;Park, Yoon-Kyung;Hahm, Kyung-Soo;Kim, Yang-Mee
    • Journal of the Korean Magnetic Resonance Society
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    • v.13 no.1
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    • pp.27-34
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    • 2009
  • HP (2-20), a 19-residue peptide derived from the N-terminus of Helicobacter pylori Ribosomal Protein L1, has antimicrobial activity but is not cytotoxic to human erythrocytes. Previously, we have synthesized several analogue peptides to investigate the effects of substitutions on the structure and antimicrobial activity. Substitution of $Gln^{16}$ and $Asp^{18}$ with Trp (Anal 3) caused a dramatic increase in bacterial and fungal lytic activities. In this study, analogue peptides were synthesized to investigate the effects of substitution of Gin and Asp with Phe (Anal 6) or Tyr (Anal 7) in HP (2-20) on its structure and antimicrobial activity. Substitution of Gin and Asp with hydrophobic aromatic residues at position 16 and 18 of HP (2-20) caused increase in antibiotic activity without hemolytic effect. Substitution of Gin and Asp with Trp and Try increased antibiotic activity of HP (220) twice more compared to substitution with Phe. The tertiary structures of Anal 6 and Anal 7 in SDS micelles has been investigated using NMR spectroscopy. The structures revealed that substitutions of the aromatic residues at C-terminus resulted in longer and well defined alpha-helix and improved their antibacterial activities

Mechanical Properties of Alkali Treated Kenaf Fiber Filled PP Bio-Composites (알칼리 처리된 Kenaf 섬유가 충전된 Polypropylene/Kenaf 바이오복합재의 기계적 특성)

  • Kim, Samsung;Lee, Byoung-Ho;Kim, Hyun-Joong;Oh, Sei Chang;Ahn, Sye-Hee
    • Journal of the Korean Wood Science and Technology
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    • v.37 no.3
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    • pp.222-230
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    • 2009
  • This study was to investigate the effect of alkali treatment for long kenaf fiber to improve fiber surface characterics by removal of wax, lignin and hemicellulose which affect adversely for matrix union. SEM observation was also studied to check out the interface adhesion improvement by the alkali pre-treatment. From the result, interface coherence increased by 3% alkali pre-treatment and reached a maximum by 5% alkali pre-treatment. However, the 3% the bio-composites treated with 3% alkali was highest tensile and flexural strength than other.

Enzymatic bioconversion of ginseng powder increases the content of minor ginsenosides and potentiates immunostimulatory activity

  • Park, Jisang;Kim, Ju;Ko, Eun-Sil;Jeong, Jong Hoon;Park, Cheol-Oh;Seo, Jeong Hun;Jang, Yong-Suk
    • Journal of Ginseng Research
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    • v.46 no.2
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    • pp.304-314
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    • 2022
  • Background: Ginsenosides are biologically active components of ginseng and have various functions. In this study, we investigated the immunomodulatory activity of a ginseng product generated from ginseng powder (GP) via enzymatic bioconversion. This product, General Bio compound K-10 mg solution (GBCK10S), exhibited increased levels of minor ginsenosides, including ginsenoside-F1, compound K, and compound Y. Methods: The immunomodulatory properties of GBCK10S were confirmed using mice and a human natural killer (NK) cell line. We monitored the expression of molecules involved in immune responses via enzyme-linked immunosorbent assay, flow cytometry, NK cell-targeted cell destruction, quantitative reverse-transcription real-time polymerase chain reaction, and Western blot analyses. Results: Oral administration of GBCK10S significantly increased serum immunoglobulin M levels and primed splenocytes to express pro-inflammatory cytokines such as interleukin-6, tumor necrosis factor-α, and interferon-γ. Oral administration of GBCK10S also activated NK cells in mice. Furthermore, GBCK10S treatment stimulated a human NK cell line in vitro, thereby increasing granzyme B gene expression and activating STAT5. Conclusion: GBCK10S may have potent immunostimulatory properties and can activate immune responses mediated by B cells, Th1-type T cells, and NK cells.

Fabrication of Tailor-Made 3D PCL Scaffold Using a Bio-Plotting Process (바이오-플로팅시스템을 통한 Tailor-Made 3D PCL Scaffold 제작)

  • Son, Joon-Gon;Kim, Geun-Hyung;Park, Su-A;Kim, Wan-Doo
    • Polymer(Korea)
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    • v.32 no.2
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    • pp.163-168
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    • 2008
  • Biomedical scaffold for tissue regeneration was fabricated by one of rapid prototyping processes, bioplotting system, with a biodegradable and biocompatible poly($\varepsilon$-carprolactone)(PCL). Through dynamic mechanical test, it was observed that the PCL scaffold manufactured by the bioplotting process has the superior mechanical properties compared to the conventional scaffold fabricated by a salt-leaching process, and the plotted scaffold could be employed as a potential scaffold to regenerating hard and soft tissue. The plotted scaffold was consisted of porous structures. which were interconnected with each pore to help cells be easily adhered and proliferated in the wall of pore tunnels, and metabolic nutrients can be transported within the matrix. By using the plotting system, we could adjust the pore size, porosity, strand pitch, and, strand diameter of PCL scaffolds, which were important parameters to control mechanical properties of the scaffolds, and consequently we could determine that the mechanically controlled scaffolds could be used as a matching scaffold for any required mechanical properties of the target organ. The fabricated 3D PCL scaffold showed enough possibility as a 3D biomedical scaffold, which was cell-cultured with chondrocytes.

Recent Aspects of Eco-friendly Textile Processing

  • Toru Takagishi;Cho, Sung-Mi
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.10a
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    • pp.3-4
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    • 2003
  • The recent aspects of eco-friendly textile processing, in particular bio-scouring of cotton and shrinkproofing of wool are described.

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