• Title/Summary/Keyword: bioactive material

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Activation of JNK and c-Jun Is Involved in Glucose Oxidase-Mediated Cell Death of Human Lymphoma Cells

  • Son, Young-Ok;Jang, Yong-Suk;Shi, Xianglin;Lee, Jeong-Chae
    • Molecules and Cells
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    • 제28권6호
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    • pp.545-551
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    • 2009
  • Mitogen-activated protein kinases (MAPK) affect the activation of activator protein-1 (AP-1), which plays an important role in regulating a range of cellular processes. However, the roles of these signaling factors on hydrogen peroxide ($H_2O_2$)-induced cell death are unclear. This study examined the effects of $H_2O_2$ on the activation of MAPK and AP-1 by exposing the cells to $H_2O_2$ generated by either glucose oxidase or a bolus addition. Exposing BJAB or Jurkat cells to $H_2O_2$ affected the activities of MAPK differently according to the method of $H_2O_2$ exposure. $H_2O_2$ increased the AP-1-DNA binding activity in these cells, where continuously generated $H_2O_2$ led to an increase in mainly the c-Fos, FosB and c-Jun proteins. The c-Jun-$NH_2$-terminal kinase (JNK)-mediated activation of c-Jun was shown to be related to the $H_2O_2$-induced cell death. However, the suppression of $H_2O_2$-induced oxidative stress by either JNK inhibitor or c-Jun specific antisense transfection was temporary in the cells exposed to glucose oxidase but not to a bolus $H_2O_2$. This was associated with the disruption of death signaling according to the severe and prolonged depletion of reduced glutathione. Overall, these results suggest that $H_2O_2$ may decide differently the mode of cell death by affecting the intracellular redox state of thiol-containing antioxidants, and this depends more closely on the duration exposed to $H_2O_2$ than the concentration of this agent.

Glycoproteins isolated from Atractylodes macrocephala Koidz improve protective immune response induction in a mouse model

  • Kim, Kyoung-A.;Son, Young-Ok;Kim, So-Soon;Jang, Yong-Suk;Baek, Young-Hyun;Kim, Chun-Chu;Lee, Jeong-Hoon;Lee, Jeong-Chae
    • Food Science and Biotechnology
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    • 제27권6호
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    • pp.1823-1831
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    • 2018
  • This study examined the efficacy of Atractylodes macrocephala Koidz (AMK) protein and polysaccharide extracts as adjuvant or adjuvant booster when given together with porcine pleuropneumonia vaccine. Experimental mice (n = 5/group) were subcutaneously immunized with $25{\mu}g$ ApxIIA #3 antigen, a target protein against A. pleuropneumoniae, together with alum and/or various concentrations ($0-500{\mu}g$) of the AMK extracts, while the control group received PBS only. Immunization with ApxIIA #3 antigen increased the antigen-specific IgG titer and this increase was enhanced in the immunization together with AMK protein, but not polysaccharide extract. Supplementation of AMK protein extract exhibited dose-dependent increases in the antigen-induced protective immunity against A. pleuropneumoniae challenge and in the lymphocyte proliferation specific to the antigen. Glycoproteins present in the AMK extract were the active components responsible for immune response induction. Collectively, the present findings suggest that AMK glycoproteins are useful as immune stimulating adjuvant or adjuvant booster.

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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    • 제46권2호
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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.

Mechanism of Apatite Formation on Bioactive Titanium Metal

  • Kim, Hyun-Min;Takadama, Hiroaki;Miyaji, Fumiaki;Kokubo, Tadashi;Nishiguchi, Shigeru;Nakamura, Takashi
    • The Korean Journal of Ceramics
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    • 제4권4호
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    • pp.336-339
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    • 1998
  • Bioactive titanium metal can be prepared by simple 5M-NaOH treatment and subsuquent heat treatment at $600^{\circ}C$ to form an amorphous sodium titanate on its surface. In the present study, mechanism of apatite formation on the titanium metal was investigated by examining its surface compositional and structural changes in a simulated body fluid. The apatite formation on the metal was found to proceed in the sequence of 1)$Na^+$ ion release from the sodium titanate to form hydrated titania abundant in Ti-OH groups, 2) early and selective binding of calcium ions with the Ti-OH groups to form a calcium titanate, and 3) late binding of phosphate ions to make apatite nucleation and growth. This indicates that Ti-OH groups do not directly induce the apatite nucleation, but via formation of a calcium titanate.

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Ring and Volcano Structures Formed by a Metal Dipyrromethene Complex

  • Son, Seung Bae;Miao, Qing;Shin, Ji-Young;Dolphin, David;Hahn, Jae Ryang
    • Bulletin of the Korean Chemical Society
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    • 제35권6호
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    • pp.1727-1731
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    • 2014
  • Dichloromethane liquid droplets containing a cobalt dipyrromethene trimer deposited on a graphite surface were found to form coffee ring, toroid ring, or volcano dot structures due to the redistribution of the solute during solvent evaporation. The shapes and size distributions of the ring structures depended on the drying temperature. The shape differences were attributed to the fact that the solvent evaporation rate controlled the self-assembly process that yielded the coffee stain and pinhole structures.

The Synthesis of Diverse Adenosine 5'-phosphonate Analogues as Chain Terminators against Hepatitis C Virus (HCV)

  • Kim, Bo-Seung;Kim, Beom-Tae;Hwang, Ki-Jun
    • Bulletin of the Korean Chemical Society
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    • 제31권6호
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    • pp.1643-1648
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    • 2010
  • Adenosine 5'-phosphonates have been reported as potential chain terminators against Hepatitis C virus (HCV); therefore, we developed convenient sequences for synthesis of modified adenosine 5'-phosphonates in which the hydroxyl group at 2' or 3'-position of the sugar moiety is substituted with the azido or amino group and the oxymethyl group at the 4'-position is modified by the ethylene or vinyl group. This synthetic sequence can provide six adenosine 5'-phosphonates via one protocol, and is considered to be very efficient and a convenient route of synthesis. An assay of adenosine 5'-phosphonate analogues (1, 2, 3, 4, 5, and 6) against HCV infection is now in progress.

A Promising Vaccination Strategy against COVID-19 on the Horizon: Heterologous Immunization

  • Mattoo, Sameer-ul-Salam;Myoung, Jinjong
    • Journal of Microbiology and Biotechnology
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    • 제31권12호
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    • pp.1601-1614
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    • 2021
  • To overcome the ongoing COVID-19 pandemic, vaccination campaigns are the highest priority of majority of countries. Limited supply and worldwide disproportionate availability issues for the approved vaccines, together with concerns about rare side-effects have recently initiated the switch to heterologous vaccination, commonly known as mixing of vaccines. The COVID-19 vaccines are highly effective in the general population. However, none of the vaccines is 100% efficacious or effective, with variants posing more challenges, resulting in breakthrough cases. This review summarizes the current knowledge of immune responses to variants of concern (VOC) and breakthrough infections. Furthermore, we discuss the scope of heterologous vaccination and future strategies to tackle the COVID-19 pandemic, including fractionation of vaccine doses and alternative route of vaccination.

Effect of Lactic Fermentation and Spray Drying Process on Bioactive Compounds from Ngoc Linh Ginseng Callus and Lactobacillus plantarum Viability

  • Dong, Lieu My;Linh, Nguyen Thi Thuy;Hoa, Nguyen Thi;Thuy, Dang Thi Kim;Giap, Do Dang
    • 한국미생물·생명공학회지
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    • 제49권3호
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    • pp.346-355
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    • 2021
  • Ngoc Linh ginseng is one of the most valuable endemic medicinal herbs in Vietnam. In this study, Ngoc Linh ginseng callus was fermented by Lactobacillus plantarum ATCC 8014 (at 6, 7, and 8 log CFU/ml) to evaluate the extraction efficiency of bioactive compounds. The post-fermentation solution was spray-dried using maltodextrin with or without Stevia rebaudiana (3% and 6% v/v) as the wall material. Bioactive compounds such as polyphenols, polysaccharides, and total saponins, and L. plantarum viability during fermentation and after spray-drying, as well as under simulated gastric digestion, were evaluated in this study. The results showed that probiotic density had a significant effect on bioactive compounds, and L. plantarum at 8 log CFU/ml showed the best results with a short fermentation time compared to other tests. The total content of polyphenols, polysaccharides, and saponins reached 5.16 ± 0.18 mg GAE/g sample, 277.2 ± 6.12 mg Glu/g sample, and 4.17 ± 0.15 mg/g sample, respectively after 20 h of fermentation at the initial density of L. plantarum (8 log CFU/ml). Although there was no difference in the particle structure of the preparation, the microencapsulation efficiency of the bioactive compound in the samples containing S. rebaudiana was higher than that with only maltodextrin. The study also indicated that adding S. rebaudiana improved the viability of L. plantarum in gastric digestion. These results showed that S. rebaudiana, a component stimulating probiotic growth, combined with maltodextrin as a co-prebiotic, improved the survival rate of L. plantarum in simulated gastric digestion.