• Title/Summary/Keyword: Improved synthesis

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Enzymatic Synthesis of Flame Retardant Phenolic Polymers Catalyzed by Horseradish Peroxidase (Horseradish Peroxidase 효소촉매에 의한 난연성 페놀고분자의 합성)

  • Park, Han Sol;Park, Jung Hee;Lee, Hak Sung;Ryu, Keungarp
    • Korean Chemical Engineering Research
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    • v.51 no.1
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    • pp.111-115
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    • 2013
  • The optimum synthetic conditions of poly(p-phenylphenol) by horseradish peroxidase in dioxane:water (80:20 v/v) mixtures were studied. The stability against thermal degradation and structural properties of the synthesized phenolic resins were investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), respectively. The synthetic yield of poly(p-phenylphenol) increased upon the increase of the amount of enzyme up to 0.25 mg HRP/mL, then leveled off for further increase of the enzyme usage. When sodium acetate (100 mM, pH 4~6) and sodium phosphate (100 mM, pH 7~9) were used as the buffering salts for the aqueous component (20% v/v), the synthetic yield of the resin increased at higher pH of the aqueous buffer. But when the pHs of the aqueous buffer were 6 and 9, the synthetic yield strongly depended on the types of the buffering salts; if sodium phosphate was used instead of sodium acetate at pH 6, the yield decreased by about 15% and if sodium bicarbonate was used instead of sodium phosphate, the yield decreased by almost 20%. When the pH range of the aqueous buffer was from 4 to 7, the addition of a radical mediator, 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonate) (ABTS), up to 2 mM improved the synthetic yield of the resin by about 10%. TGA experiments revealed that the thermal stability of the resin synthesized in dioxane:water (100 mM sodium phosphate, pH 9) (80:20 v/v) was high having the char yield of 47% upon the heating at $800^{\circ}C$. DCS results showed that the structures of the polymers synthesized in acidic aqueous buffers were different from those of the polymers synthesized in the basic aqueous buffers. However, all the synthesized resins were found to have the property of the thermosetting resins.

Identification of the Pig β-1,3-N-acetylglucosaminyltransferase 1 (pB3GNT1) that is Involved in Poly-N-acetyllactosamine (poly-LacNAc) Synthesis (Poly-N-acetyllactosamine (poly-LacNAc) 합성에 관여하는 돼지 β-1,3-N-acetylglucosaminyltransferase I (pB3GNT1) 유전자 동정)

  • Kim, Ji-Youn;Hwang, Hwan-Jin;Chung, Hak-Jae;Hochi, Shinichi;Park, Mi-Ryung;Byun, Sung June;Oh, Keon Bong;Yang, Hyeon;Kim, Kyung-Woon
    • Journal of Life Science
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    • v.28 no.4
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    • pp.389-397
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    • 2018
  • The structure of glycan residues attached to glycoproteins can influence the biological activity, stability, and safety of pharmaceutical proteins delivered from transgenic pig milk. The production of therapeutic glycoprotein in transgenic livestock animals is limited, as the glycosylation of mammary gland cells and the production of glycoproteins with the desired homogeneous glycoform remain a challenge. The ${\beta}$-1,3-N-acetylglucosaminylatransferase1 (B3GNT1) gene is an important enzyme that attaches N-acetylglucosamine (GlcNAc) to galactose (Gal) residues for protein glycosylation; however, there is limited information about pig glycosyltransferases. Therefore, we cloned the pig B3GNT1 (pB3GNT1) and investigated its functional properties that could attach N-acetylglucosamine to galactose residue. Using several different primers, a partial pB3GNT1 mRNA sequence containing the full open reading frame (ORF) was isolated from liver tissue. The ORF of pB3GNT1 contained 1,248 nucleotides and encoded 415 amino acid residues. Organ-dependent expression of the pB3GNT1 gene was confirmed in various organs from adult and juvenile pigs. The pB3GNT1 mRNA expression level was high in the muscles of the heart and small intestine but was lower in the lungs. For functional characterization of pB3GNT1, we established a stable expression of the pB3GNT1 gene in the porcine kidney cell line (PK-15). As a result, it was suggested that the glycosylation pattern of pB3GNT1 expression in PK-15 cells did not affect the total sialic acid level but increased the poly N-acetyllactosamine level. The results of this study can be used to produce glycoproteins with improved properties and therapeutic potential for the generation of desired glycosylation using transgenic pigs as bioreactors.

Protection of UV-derived Skin Cell Damage and Anti-irritation Effect of Juniperus chinensis Xylem Extract (향나무추출물의 광손상으로부터 피부세포 보호와 자극완화 효과에 대한 연구)

  • 김진화;박성민;심관섭;이범천;표형배
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.30 no.1
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    • pp.63-71
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    • 2004
  • The human skin is constantly exposed to environmental irritants such as ultraviolet, smoke, chemicals. Free radicals and reactive oxygen species (ROS) caused by these environmental facts play critical roles in cellular damage. These irritants are in themselves damaging to the skin structure but they also participate the immensely complex inflammatory reaction. The purpose of this study was to investigate the skin cell protective effect of Juniperus chinensis xylem extract on the UV and SLS-induced skin cell damages. We tested free radical and superoxide scavenging effect in vitro. We found that Juniperus chinensis xylem extracts had potent radical scavenging effect by 98% at 100 $\mu\textrm{g}$/mL. Fluorometric assays of the proteolytic activities of matrix metalloproteinase-l(MMP-1, collagenase) were performed using fluorescent collagen substrates. UV A induced MMP-1 synthesis and activity were analyzed by enzyme-linked immunosorbent assay (ELISA) and gelatin-based zymography in skin fibroblasts. The extract of Juniperus chinensis showed strong inhibitory effect on MMP-1 activities by 97% at 100 $\mu\textrm{g}$/mL and suppressed the UVA induced expression of MMP-1 by 79% at 25 $\mu\textrm{g}$/mL. This extract also showed strong inhibition on MMP-2 activity in UVA irradiated fibroblast by zymography. We also examined anti-inflammatory effects by the determination test of proinflammatory cytokine, interleukin 6 in HaCaT keratinocytes. In this test Juniperus chinensis decreased expression of interleukin 6 about 30%. Expression of prostaglandin E$_2$, (PGE$_2$) after UVB irradiation was measured by competitive enzyme immunoassay (EIA) using PGE$_2$ monoclonal antibody. At the concentrations of 5-50 $\mu\textrm{g}$/mL of the extracts, the production of PGE$_2$ by HaCaT keratinocytes (24 hours after 10 mJ/$\textrm{cm}^2$ UVB irradiation) was significantly inhibited in culture supernatants (p〈0.05). The viability of cultured HaCaT keratinocytes was significantly reduced at the doses of above 10 mJ/$\textrm{cm}^2$ of UVB irradiation, but the presence of these extracts improved cell viability comparing to control after UVB irradiation. We also investigated the protective effect of this extract in sodium lauryl sulfate (SLS)-induced irritant skin reactions from 24 hour exposure. Twice a day application of the extract for reducing local inflammation in human skin was done. Irritant reactions were assessed by various aspects of skin condition, that is, erythema (skin color reflectance) and transepidermal water loss (TEWL). After 5 days the extract was found to reduce SLS-induced skin erythema and improve barrier regeneration when compared to untreated symmetrical test site. In conclusion, our results suggest that Juniperus chinensis can be effectively used for the prevention of UV and SLS-induced adverse skin reactions such as radical production, inflammation and skin cell damage.

Anti-wrinkle and Whitening Effects of Essential Oil from Abies koreana (Abies koreana 유래 정유의 항주름 및 미백 효과)

  • Song, Byeong-Wook;Song, Min-Jeong;Park, Mi-Jin;Choi, Don-Ha;Lee, Sung-Suk;Kim, Myungkil;Hwang, Ki-Chul;Kim, Il-Kwon
    • Journal of Life Science
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    • v.28 no.5
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    • pp.524-531
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    • 2018
  • The essential oil from Abies koreana E.H. Wilson had been developed, however, its efficacy has not yet been studied especially in terms of skin care research. The aim of this study is to investigate the effects of Abies koreana extracts (AKE) on melanogenesis and wrinkle formation in B16F10 melanoma cells (B16F10) and human dermal fibroblast cell line (HDF). The essential oil was extracted by hydrodistillation method and purified by anhydrous sodium sulfate. At a concentration of $10^{-5}$-fold, viability in these cells had been defined by cytotoxicity assays. Anti-melanogenic effects on B16F10 were evaluated using tyrosinase inhibition assay, and real-time PCR for verifying gene expression of tyrosinase, tyrosinase related protein-1 and -2 (TRP-1 and -2). AKEs reduced about 5-fold of tyrosinase inhibitory activity compared to ${\alpha}$-melanocyte-stimulating hormone (${\alpha}$-MSH)-induced group and about 30% reduction compared to Arbutin induced group. The mRNA levels of three melanin-related factors were increased, separately. To investigate the effects of anti-wrinkle, procollagen type I c peptide synthesis assay (PIP) and Western blot were performed. At AKE-treated group, PIP was up-regulated and the expression of collagen type 1 and matrix metalloproteinase (MMP)-1 were improved. Furthermore, AKE presented anti-wrinkle effects by increasing UVB-inhibited collagen type 1 expression, and reducing UVB-induced MMP-1 production at $60mJ/cm^2$ of UVB radiation. Therefore, Abies koreana extracts has potentials as a safe and an effective skin ingredient for whitening and anti-wrinkle.

Effect of the Preparation Method on the Activity of CeO2-promoted Co3O4 Catalysts for N2O Decomposition (촉매 제조방법에 따른 Co-CeO2 촉매의 N2O 분해 특성 연구)

  • Kim, Hye Jeong;Kim, Min-Jae;Lee, Seung-Jae;Ryu, In-Soo;Yi, Kwang Bok;Jeon, Sang Goo
    • Clean Technology
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    • v.24 no.3
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    • pp.198-205
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    • 2018
  • This study investigated the influence of catalyst preparation on the activity of $Co-CeO_2$ catalyst for $N_2O$ decomposition. $Co-CeO_2$ catalysts were synthesized by co-precipitation and incipient wetness impregnation. In order to estimate the performance of the as prepared catalysts, direct catalytic $N_2O$ decomposition test was carried out under $250{\sim}375^{\circ}C$. As a result, the catalyst prepared by co-precipitation (CoCe-CP) showed an enhanced performance on $N_2O$ decomposition reaction even in the presence of $O_2$ and/or $H_2O$, whereas the impregnation catalyst (CoCe-IM) did not. In order to investigate the difference in catalytic activity, characterization such as XRD, BET, TEM, $H_2-TPR$, $O_2-TPD$, and XPS was conducted. It is confirmed that the particle size and specific surface area were changed depending on the catalyst preparation method and the synthesis process influenced the physical properties of the catalysts. In addition, the improvement in the activity of the catalyst prepared by co-precipitation is due to the enhanced reduction from $Co^{3+}$ to $Co^{2+}$ and the improved oxygen desorption rate. However, it has been confirmed that the surface electron state and binding energy, which are related to $N_2O$ decomposition, do not change depending on the preparation method.

Anti-wrinkle Activity of $\beta$-carotene Extracted & Purified from Recombinant Escherichia coli (재조합 대장균으로부터 추출.정제된 베타-카로틴의 주름개선 활성)

  • Jo, Ji-Song;Ku, Bo-Mi;Kang, Sang-Soo;Lee, Jae-Ran;Kim, You-Geun;Lee, He;Kim, Sung-Bae;Kim, Seon-Won;Kim, Chang-Joon;Chung, In-Young
    • KSBB Journal
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    • v.23 no.6
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    • pp.513-518
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    • 2008
  • This paper described the extraction/purification of $\beta$-carotene from recombinant E.coli and evaluation of anti-wrinkle activity of purified $\beta$-carotene. No significant differences in extraction yields were observed when hexane or isobutyl acetate was used. However, extraction from wet-cell cake resulted in 2-fold higher amount of $\beta$-carotene than that from dry cells. Disruption of 5 g-wet cells by ultrasonic homogenizer, acetone dehydration, extraction with isobutyl acetate resulted in 36 mg of $\beta$-carotene corresponding to 61.2% of recovery. The formation and separation of $\beta$-carotene crystal improved the purity. 633 mg of $\beta$-carotene crystal with 93% purity was obtained from 223 g/L of wet-cell cake harvested from 2.5-L fed-batch culture broth. The cultures of normal human primary fibroblast were performed to investigate the effect of $\beta$-carotene on cytotoxicity as MTT assay and anti-wrinkle activity as collagen synthesis assays. $1.7{\mu}M$ of $\beta$-carotene was found to be optimal concentration at which 1.4-fold higher amount of collagen was synthesized than that in absence of $\beta$-carotene. This indicates that highly purified $\beta$-carotene can be obtained from recombinant E.coli by applying simple method with less toxic solvent and can be used in functional cosmetics as anti-wrinkle agent.

Preparation of Novel Natural Polymer-based Magnetic Hydrogels Reinforced with Hyperbranched Polyglycerol (HPG) Responsible for Enhanced Mechanical Properties (과분지 폴리글리세롤(HPG) 강화를 통해 기계적 물성이 향상된 새로운 천연 고분자 기반 자성 하이드로젤의 제조)

  • Eun-Hye Jang;Jisu Jang;Sehyun Kwon;Jeon-Hyun Park;Yujeong Jeong;Sungwook Chung
    • Clean Technology
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    • v.29 no.1
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    • pp.10-21
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    • 2023
  • Hydrogels that are made of natural polymer-based double networks have excellent biocompatibility, low cytotoxicity, and high water content, assuring that the material has the properties required for a variety of biomedical applications. However, hydrogels also have limitations due to their relatively weak mechanical properties. In this study, hydrogels based on an alginate di-aldehyde (ADA) and gelatin (Gel) double network that is reinforced with additional hydrogen bonds formed between the hydroxyl (-OH) groups of the hyperbranched polymer (HPG) and the functional groups present inside of the hydrogels were successfully synthesized. The enhanced mechanical properties of these synthesized hydrogels were evaluated by varying the amount of HPG added during the hydrogel synthesis from 0 to 25%. In addition, magnetite nanoparticles (Fe3O4 NPs) were synthesized within the hydrogels and the structures and the magnetic properties of the hydrogels were also characterized. The hydrogels that contained 15% HPG and Fe3O4 NPs exhibited superparamagnetic behaviors with a saturation magnetization value of 3.8 emu g-1. These particular hydrogels also had strengthened mechanical properties with a maximum compressive stress of 1.1 MPa at a strain of 67.4%. Magnetic hydrogels made with natural polymer-based double networks provide improved mechanical properties and have a significant potential for drug delivery and biomaterial application.

Effects of polygalacin D extracted from Platycodon grandiflorum on myoblast differentiation and muscle atrophy (길경에서 추출한 polygalacin D가 근원세포 분화 및 근위축에 미치는 영향)

  • Eun-Ju Song;Ji-Won Heo;Jee Hee Jang;Eonmi Kim;Yun Hee Jeong;Min Jung Kim;Sung-Eun Kim
    • Journal of Nutrition and Health
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    • v.56 no.6
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    • pp.602-614
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    • 2023
  • Purpose: The balance between synthesis and degradation of proteins plays a critical role in the maintenance of skeletal muscle mass. Mitochondrial dysfunction has been closely associated with skeletal muscle atrophy caused by aging, cancer, and chemotherapy. Polygalacin D is a saponin derivative isolated from Platycodon grandiflorum (Jacq.) A. DC. This study aimed to investigate the effects of polygalacin D on myoblast differentiation and muscle atrophy in association with mitochondrial function in in vitro and in zebrafish models in vivo. Methods: C2C12 myoblasts were cultured in differentiation media containing different concentrations of polygalacin D, followed by the immunostaining of the myotubes with myosin heavy chain (MHC). The mRNA expression of markers related to myogenesis, muscle atrophy, and mitochondrial function was determined by real-time quantitative reverse transcription polymerase chain reaction. Wild type AB* zebrafish (Danio rerio) embryos were treated with 5-fluorouracil, leucovorin, and irinotecan (FOLFIRI) with or without polygalacin D, and immunostained to detect slow and fast types of muscle fibers. The Tg(Xla.Eef1a1:mitoEGFP) zebrafish expressing mitochondria-targeted green fluorescent protein was used to monitor mitochondrial morphology. Results: The exposure of C2C12 myotubes to 0.1 ng/mL of polygalacin D increased the formation of MHC-positive multinucleated myotubes (≥ 8 nuclei) compared with the control. Polygalacin D significantly increased the expression of MHC isoforms (Myh1, Myh2, Myh4, and Myh7) involved in myoblast differentiation while it decreased the expression of atrophic markers including muscle RING-finger protein-1 (MuRF1), mothers against decapentaplegic homolog (Smad)2, and Smad3. In addition, polygalacin D promoted peroxisome proliferator-activated receptor-gamma coactivator (Pgc1α) expression and reduced the level of mitochondrial fission regulators such as dynamin-1-like protein (Drp1) and mitochondrial fission 1 (Fis1). In a zebrafish model of FOLFIRI-induced muscle atrophy, polygalacin D improved not only mitochondrial dysfunction but also slow and fast muscle fiber atrophy. Conclusion: These results demonstrated that polygalacin D promotes myogenesis and alleviates chemotherapy-induced muscle atrophy by improving mitochondrial function. Thus, polygalacin D could be useful as nutrition support to prevent and ameliorate muscle wasting and weakness.