• Title/Summary/Keyword: supercritical

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Antioxidant and Antiaging Activities of Complex Supercritical Fluid Extracts from Dendropanax morbifera, Corni fructus and Lycii Fructus (황칠나무, 산수유, 구기자 복합 초임계유체추출물의 항산화 및 항노화 효과)

  • Shin, Dong-Chul;Kim, Gwui-Cheol;Song, Si-Young;Kim, Hee-Jin;Yang, Jae-Chan;Kim, Bo-Ae
    • The Korea Journal of Herbology
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    • v.28 no.6
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    • pp.95-100
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    • 2013
  • Objectives : The purpose of this study was to investigate antiaging and antioxidant effects on cultured human skin fibroblast with supercritical fluid extracts of Dendropanax morbifera, Corni fructus and Lycii Fructus. Methods : Supercritical fluid extraction (SFE) technique was applied to extract from three medicinal plants including stem of Dendropanax morbifera, Corni fructus and Lycii Fructus. Antioxidant activity of extract was evaluated by two different assays as 2,2-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and super oxide dismutase (SOD) like activities. These extracts were tested for cell viability on HS68 skin fibroblast by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay. We investigated the effects of Ultraviolet-B irradiation on cytotoxicity, type 1 collagen, elastin level and oxidative damage in cultured human skin fibroblast (HS68). Recently, many studies have reported that elastin is also involved in inhibiting or repairing wrinkle formation, although collagen is a major factor in the skin wrinkle formation. Results : The extracts obtained dose-dependently increased the scavenging activity on DPPH radical scavenging activity and SOD like activity. The supercritical fluid extracts of complex herbal medicine showed low cytotoxicity as more than 100% cell viability in 100ppm/ml concentration. HS68 fibroblasts were survived 70% at $120mJ/cm^2$ UVB irradiation and treated tumor necrosis factor (TNF)-alpha. The levels of aging factors and cytotoxicity were decreased by supercritical fluid extract of complex herbal medicine. Conclusions : These results suggest that supercritical fluid extracts may have value as the potential antioxidant and antiaging medicinal plant.

Collagen Extraction Using Supercritical CO2 from Animal-Derived Waste Tissue (동물 유래 폐지방으로부터 초임계 CO2를 이용한 콜라겐 추출)

  • No, Seong-Rae;Shin, Yong-Woo;You, Seong-sik
    • Korean Chemical Engineering Research
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    • v.60 no.3
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    • pp.386-391
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    • 2022
  • This study is about a technique for obtaining collagen by extracting fat by treating collagen-containing liposuction effluent in the presence of supercritical fluid. Using a supercritical solvent, a collagen extract could be obtained from animal-derived fat in a short time (about 6 hours), and about 2-3% of collagen by mass compared to the raw material could be obtained. The presence of collagen in the extract obtained by supercritical extraction was confirmed by SDS-PAGE, and it was confirmed that it was type 1 collagen having a relatively large molecular weight. In addition, the growth factors of IGF-1, bFGF, VEGF and NGF were analyzed to find out which growth factors were present in the collagen obtained by supercritical extraction, and it was found that these growth factors were contained in the extract. There was no significant difference in DNA content per mg of sample before and after supercritical treatment. Further in-depth studies are likely to be needed on decellularization technology using the supercritical process. In conclusion, the extracellular matrix obtained through the solvent extraction process using a supercritical fluid contains growth factors above a certain amount even after decellularization and removal of fat, so that it was found that not only biocompatibility is greatly increased, but also tissue regeneration can be rapidly induced.

High-pressure rheology of polymer melts containing supercritical carbon dioxide

  • Lee Sang-Myung;Han Jae-Ro;Kim Kyung-Yl;Ahn Young-Joon;Lee Jae-Wook
    • Korea-Australia Rheology Journal
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    • v.18 no.2
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    • pp.83-90
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    • 2006
  • Supercritical carbon dioxide ($scCO_2$) has advantages of being incorporated in polymer with high solubility and of being recovered easily by depressurizing. $scCO_2$ reduces the viscosity of polymer melt and it is expected to be use as a plasticizing agent. In this work, we studied on the effect of $scCO_2$ on the rheological properties of polymer melts during extrusion process. Slit die attached to twin screw extruder was used to measure the viscosity of polymer melts plasticized by supercritical $CO_2$. A gas injection system was devised to accurately meter the supercritical $CO_2$ into the extruder barrel. Measurements of pressure drop within the die, confirmed the presence of a one phase mixture and a fully developed flow during the measurements. The viscosity measurement of polypropylene was performed at experimental conditions of various temperatures, pressures and $CO_2$ concentrations. We observed that melt viscosity of polymer was dramatically reduced by $CO_2$ addition.

Lipase-catalyzed Esterification of (S)-Naproxen Ethyl Ester in Supercritical Carbon Dioxide

  • Kwon, Cheong-Hoon;Lee, Jong-Ho;Kim, Seung-Wook;Kang, Jeong-Won
    • Journal of Microbiology and Biotechnology
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    • v.19 no.12
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    • pp.1596-1602
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    • 2009
  • A lipase-catalyzed esterification reaction of (S)-naproxen ethyl ester by CALB (Candida antarctica lipase B) enzyme was performed in supercritical carbon dioxide. Experiments were performed in a high-pressure cell for 10 h at a stirring rate of 150 rpm over a temperature range of 313.15 to 333.15 K and a pressure range of 50 to 175 bar. The productivity of (S)-naproxen ethyl ester was compared with the result in ambient condition. The total reaction time and conversion yields of the catalyzed reaction in supercritical carbon dioxide were compared with those at ambient temperature and pressure. The experimental results show that the conversion and reaction rate were significantly improved at critical condition. The maximum conversion yield was 9.9% (216 h) at ambient condition and 68.9% (3 h) in supercritical state. The effects of varying amounts of enzyme and water were also examined and the optimum condition was found (7 g of enzyme and 2% water content).

Coffee Deodorization with Supercritical Carbon Dioxide (초임계 이산화탄소를 이용한 커피의 탈취)

  • Lee, Joo-Hee;Kim, Hyung-Bae;Byun, Sang-Yo
    • KSBB Journal
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    • v.22 no.5
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    • pp.336-340
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    • 2007
  • Supercritical carbon dioxide was used to remove coffee odors. The odor removal efficiency was tested with coffee drink prepared by the espresso extraction method. Five typical odors in coffee were analyzed with GC and these odors in deodorized coffee were compared to those in control. Supercritical carbon dioxide extraction conditions were optimized as 350 bar and 70$^{\circ}C$ because the solvating power of supercritical fluid is depend on the density which is determined by temperature and pressure. A modified head space method was applied to collect coffee odors in coffee drink prepared by the espresso extraction method. Odors generated in coffee drink made with deodorized coffee powder were reduced by 73% in total mass of typical five coffee odors.

Decomposition of PVC and Ion Exchange Resin in Supercritical Water

  • Kim Jung-Sung;Lee Sang-Hwan;Park Yoon-Yul;Yasuyo Hoshikawa;Hiroshi Tomiyasu
    • Journal of Environmental Science International
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    • v.14 no.10
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    • pp.919-928
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    • 2005
  • This study introduces the development of new supercritical water oxidation(SCW)(multiple step oxidation) to destruct recalcitrant organic substances totally and safely by using sodium nitrate as an oxidant. This method has solved the problems of conventional SCW, such as precipitation of salt due to lowered permittivity, pressure increase following rapid rise of reaction temperature, and corrosion of reactor due to the generation of strong acid. Destruction condition and rate in the supercritical water were examined using Polyvinyl Chloride(PVC) and ion exchange resins as organic substances. The experiment was carried out at $450^{\circ}C$ for 30min, which is relatively lower than the temperature for supercritical water oxidation $(600-650^{\circ}C)$. The decomposition rates of various incombustible organic substances were very high [PVC$(87.5\%)$, Anion exchange resin$(98.6\%)$, Cationexchange resin$(98.0\%)$]. It was observed that hetero atoms existed in organic compounds and chlorine was neutralized by sodium (salt formation). However, relatively large amount of sodium nitrate (4 equivalent) was required to raise the decomposition ratio. For complete oxidation of PCB was intended, the amount of oxidizer was an important parameter.

Preparation of TiO2 and TiO2-CdS Photocatalayst Using the Supercritical Fluid Method (초임계 유체법에 의한 TiO2 및 TiO2-CdS계 광촉매 제조에 관한 연구)

  • 김종하;박상준;황수현;정용진;전일수;조승범;전명석;임대영
    • Journal of the Korean Ceramic Society
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    • v.40 no.12
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    • pp.1220-1223
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    • 2003
  • TiO$_2$ and TiO$_2$-CdS which were expected to be highly activated photocatalysts with semiconductor properties, were prepared using supercritical fluid method. The powders prepared by supercritical fluid were agglomerate foam in 2-3 ${\mu}{\textrm}{m}$ size and the primary particles of 20 nm were arranged in the powders. The powders which were prepared by supercritical fluid method were anatase phase without any heat treatment.