• Title/Summary/Keyword: Various Solvents

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The Effect of Enhancer on the Penetration of Indapamide through Hairless Mouse Skin (경피흡수촉진제의 영향에 따른 인다파마이드의 피부투과)

  • Seo, Hui;Jeung, Sang-Young;Park, Ji-Seon;Shin, Byung-Cheol;Hwang, Sung-Joo;Cho, Sun-Hang
    • Journal of Pharmaceutical Investigation
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    • v.37 no.4
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    • pp.237-242
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    • 2007
  • The chemical formula of indapamide is 3-(aminosulfonyl)-4-chloro-N-(2,3-dihydro-2-methyl-1H-indol-l-yl)-benzamide, Indapamide is an oral antipertensive diuretic agent indicated for the treatment of hypertensive and edema. Indapamide inhibits carbonic anhydrase enzyme. Transdermal drug delivery systems, as compared to their corresponding classical oral or injectable dosage form counterparts, offer many advantages. The most important advantages are improved systemic bioavailability of the pharmaceutical active ingredients (PAI), because the first-pass metabolism by the liver and digestive system are avoided; and the controlled, constant drug delivery profile (that is, controlled zero-order absorption). Also of importance is the reduced dose frequency compared to the conventional oral dosage forms (that is, once-a-day, twice-a-week or once-a-week). Other benefits include longer duration of therapeutic action from a single application, and reversible action. For example, patches can be removed to reverse any adverse effects that may be caused by overdosing. In order to evaluate the effects of vehicles and penetration enhancers on skin permeation of Indapamide, the skin permeation rates of Indapamide from vehicles of different composition were determined using Franz cells fitted with excised hairless skins. Solubility of Indapamide in various solvents was investigated to select a vehicle suitable for the percutaneous absorption of Indapamide, The solvents used were Tween80, Tween20, Labrasol, Lauroglycol90 (LG90) and Peceol. Lauroglycol90 increase the permeability of indapamide approximately 3.75-fold compared with the control. Tween80, Tween20, Labrasol, Lauroglycol90 (LG90) and Peceol showed flux of $0.06ug/cm^2/hr,\;0.4ug/cm^2/hr,\;0.21ug/cm^2/hr,\;0.72ug/cm^2/hr,\;0.29ug/cm^2/hr$, respectively.

A Study on the Reaction Rate and Cause Analysis of Cyanoacrylate Adhesives According to the Coating Mixtures for Metal Artifacts (금속유물 코팅제와 Cyanoacrylate 접착제의 반응속도 및 원인분석: 초기접착속도를 중심으로)

  • Kwon, Hee-Hong;Huh, Il-Kwon;Kim, Soo-Ki
    • Journal of Conservation Science
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    • v.27 no.2
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    • pp.135-144
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    • 2011
  • When metal artifacts have to undergo conservation treatment, the person in charge of the treatment selects and uses various coating mixtures based on his judgment regarding their condition, material, or environment. Since the kinds of coating mixtures or solvents make a difference in the set time of cyanoacrylate adhesives, they have something to do with the efficiency of the conservation treatment. This study examines the effects and causes that affect the set time of cyanoacrylate adhesives according to the kinds of coating mixtures and solvents and suggests ways to increase the set time. As a result, it is thought that as the surface roughness gets flatter, the wettability of adhesive is improved further, which increases the set time. Moreover, the C-F binding of V-Flon, C-O-C absorption peak, molecular weight of the coating mixtures, and glass transition temperature (Tg) were the factors that significantly affected the set time. According to the result of measuring the set time based on the result of superficial and chemical analysis, relative difference was shown according to the kind and viscosity of adhesive, but all the adhesives indicated the following order of the set time: V-Flon > Paraloid B-72 (in xylene) > Paraloid NAD-10 > Paraloid B-72 (in acetone).

Antioxidant Effects of Ulmus davidiana Extracts on Various Oil (유근피와 유백피 추출액의 유지에 대한 항산화 효과)

  • Lim, Yong-Suk
    • Food Science and Preservation
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    • v.17 no.1
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    • pp.107-116
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    • 2010
  • We prepared extracts from Ulmus davidiana (root, Korean source; URK) and Ulmus davidiana (bark, Korean source; UBK). URK extracts obtained with all tested solvents showed the highest antioxidant effects on fish oils. Both treatments containing 0.1% (v/v) extract from URK and UBK each showed that peroxide values of 30 meq/kg were maintained for 6 h and levels of 40 meq/kg were apparent for up to 18 h, indicating that antioxidative activity seemed to sustain during all tested time periods. Compared with commercial antioxidants, butanol and methanol extracts diluted to 0.05% (v/v) had similar antioxidative effects. Water and butanol UBK extracts diluted to 0.1% (v/v) both showed the highest antioxidative activities. After addition of metal ions, methanol and butanol URK extracts diluted to 0.1% (v/v) showed enhanced antioxidative activity. UBK ethanol extracts displayed superior antioxidative activity and a constant peroxide value throughout storage. However, in the case of Perilla oil, $\alpha$-tocopherol which is known as a natural antioxidant did not show any antioxidative activity except in the BHT. Methanol and butanol URK extracts diluted to 0.2% (v/v) showed superior antioxidative activities throughout the experiment. A methanolic UBK extract (0.2%, v/v) also had a similarly increased antioxidative effect. In tests involving addition of metal ions to all extracts, the methanolic UBK extract (0.2%, v/v) showed excellent antioxidative activity. When lard was tested, antioxidant levels did not differ significantly among extracts prepared using four different solvents at either 0.05% or 0.1% concentrations (both v/v). Addition of metal ions at levels of 0.05% or 0.1% (w/v) to these extracts had no significant additive effect on oxidation.

An Edible Gintonin Preparation from Ginseng

  • Choi, Sun-Hye;Shin, Tae-Joon;Lee, Byung-Hwan;Hwang, Sung-Hee;Kang, Ji-Yeon;Kim, Hyun-Joong;Park, Chan-Woo;Nah, Seung-Yeol
    • Journal of Ginseng Research
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    • v.35 no.4
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    • pp.471-478
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    • 2011
  • Ginseng, the root of Panax ginseng, is one of the oldest herbal medicines. It has a variety of physiological and pharmacological effects. Recently, we isolated a subset of glycolipoproteins that we designated gintonin, and demonstrated that it induced transient change in intracellular calcium concentration $([Ca^{2+}]_i)$ in cells via G-protein-coupled receptor signaling pathway(s). The previous method for gintonin isolation included multiple steps using methanol, butanol, and other organic solvents. In the present study, we developed a much simple method for the preparation of gintonin from ginseng root using 80% ethanol extraction. The extracted fraction was designated edible gintonin. This method produced a high yield of gintonin (0.20%). The chemical characteristics of gintonin such as molecular weight and the composition of the extract product were almost identical as the gintonin prepared using the previous extraction regimen involving various organic solvents. We also examined the physiological effects of edible gintonin on endogenous $Ca^{2+}$-activated $Cl^-$ channel activity of Xenopus oocytes. The 50% effective dose was $1.03{\pm}0.3\;{\mu}g$/mL. Finally, since gintonin preparation through ethanol extraction is easily reproducible, gintonin could be commercially applied for ginseng-derived functional health food and/or drug following the confirmations of in vitro and in vivo physiological and pharmacological effects of gintonin.

Antioxidant Activity and Inhibitory Effect of Taraxacum officinale Extracts on Nitric Oxide Production (서양민들레 부위별 추출물의 항산화활성 및 nitric oxide 생성저해효과)

  • Min, Kyung-Chun;Jhoo, Jin-Woo
    • Korean Journal of Food Science and Technology
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    • v.45 no.2
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    • pp.206-212
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    • 2013
  • In the current study, antioxidant properties of extracts from different parts of Taraxacum officinale were determined by measuring the radical scavenging activity of 1,1-diphenyl-2-picryl hydrazyl(DPPH) and 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). The antioxidant activity of aerial and root parts of this plant was measured in extracts obtained from various solvents, e.g., water, 50, 70, 100% ethanol, and hot-water. The hot-water extracts had the highest radical scavenging activities. A further study was conducted to determine the total antioxidant activity of hot-water extract fractions obtained from different solvents, e.g., chloroform, ethyl acetate, n-butanol, and water. The ethyl acetate fraction of this extract displayed the strongest DPPH and ABTS radical scavenging activity and the highest total phenolic contents. The inhibitory effect of individual solvent fractions on the production of nitric oxide in LPS-stimulated RAW 264.7 cells was measured. The results indicated that the ethyl acetate fraction of aerial and roots part extracts significantly reduced nitric oxide productions.

Enhanced Migration of Gasohol Fuels in Clay Soils and Sediments (Gasoline-ethanol(Gasohol)혼합액의 점토층 내 이동에 대한 연구)

  • Hee-Chul Choi;W.M. Stallard;Kwang-Soo Kim;In-Soo Kim
    • Journal of Korea Soil Environment Society
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    • v.1 no.1
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    • pp.67-79
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    • 1996
  • Clay soils typically have low hydraulic conductivities in the presence of high polarity pore fluid, such as water. Low polarity fluids, such as hydrocarbon fuels and halogenated organic solvents, typically cannot migrate into clay pores because they cannot displace the pore water. Oxygenated additives in gasoline, such as alcohols and methyl-tert-butyl ether, are increasingly used to control air pollution emissions. These relatively polar and highly water-soluble compounds may facilitate displacement of pore water and enhance migration of fuels and solvents through clay-rich soil strata. In the reported research, the migration of gasoline-alcohol fuel mixtures (gasohol) through consolidated clay was examined. Prepared kaolinite clay samples were consolidated from slurry, and various combinations of gasoline, alcohol, and water were applied to the clays under 152 Pa gauge pressure. Movement of the fluids into the clay samples was monitored by measur ing displaced pore fluid and by magnetic resonance imaging of the samples. The structures of selected samples were examined using environmental scanning electron microscopy. Results of the research suggest that alcohol added to hydrocarbon fuels can enhance migration through some clays significantly. Gasoline did not migrate appreciably into water saturated clay, even after 14 days under pressure. The gasohol mixture migrated readily into the clay in only 20 minutes. Increased hydraulic conductivity of the clay in the presence of gasohol is hypothesized to be due to the collapse of the clays pore structure when ethanol is present, creating larger pores. Increasing pore diameter decreases the capillary pressure needed for the gasohol to replace water and allows gasohol to migrate through the clay.

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Fabrication of the poly (methyl methacrylate)/clay (modified with fluorinated surfactant) nanocomposites using supercritical fluid process (초임계 공정을 이용한 poly(methyl methacrylate)/클레이 나노복합체 제조)

  • Kim, Yong-Ryeol;Jeong, Hyeon-Taek
    • Journal of the Korean Applied Science and Technology
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    • v.31 no.2
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    • pp.231-237
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    • 2014
  • The supercritical fluids (SCFs) have been widely used for material synthesis and processing due to their remarkable properties including low viscosity, high diffusivity and low surface tension. Carbon dioxide is one of the suitable solvents in SCFs processes in terms of its advantages such as easy processibility (with low critical temperature and pressure), inexpensive, nonflammable, nontoxic, and readily available. However, it has generally low solubility for high molecular weight polymers with the exception of fluoropolymers and siloxane polymers. Therefore, hydrocarbon solvents and hydrochlorofluorocarbons have been used for various SCFs process by its high solubility for high molecular weight polymers. In this report, a PMMA/clay nanocomposites were fabricated by using supercritical fluid process. The $Na^+$-MMT(montmorillonites)was modified by a fluorinated surfactant which is able to enhance compatibility with the chlorodifluoromethane(HCFC-22) and thus, improve dispersability of the clay in the polymer matrix. The PMMA/fluorinated surfactant modified clay nanocomposite shows enhanced mechanical and thermal properties which characterized by X-raydiffraction(XRD), Thermo gravimetric analysis(TGA), Dynamic mechanical analysis (DMA) and Transmission electron microscopy (TEM).

Solvent-tolerant Lipases and Their Potential Uses (유기용매 내성 리파아제와 그 이용가능성)

  • Joo, Woo Hong
    • Journal of Life Science
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    • v.27 no.11
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    • pp.1381-1392
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    • 2017
  • This review described solvent-tolerant lipases and their potential industrial, biotechnological and environmental impacts. Although organic solvent-tolerant lipase was first reported in organic solvent-tolerant bacterium, many organic solvent-tolerant lipases are in not only solvent-tolerant bacteria but also solvent-intolerant bacterial and fungal strains, such as the well-known Bacillus, Pseudomonas, Streptomyces and Aspergillus strains. As these lipases are not easily inactivated in organic solvents, there is no need to immobilize them in order to prevent an enzyme inactivation by solvents. Therefore, the solvent-tolerant lipases have the potential to be used in many biotechnological and biotransformation processes. With the solvent-tolerant lipases, a large number insoluble substrates become soluble, various chemical reactions that are initially impossible in water systems become practical, synthesis reactions (instead of hydrolysis) are possible, side reactions caused by water are suppressed, and the possibility of chemoselective, regioselective and enantioselective transformations in solvent and non-aqueous systems is increased. Furthermore, the recovery and reuse of enzymes is possible without immobilization, and the stabilities of the lipases improve in solvent and non-aqueous systems. Therefore, lipases with organic-solvent tolerances have attracted much attention in regards to applying them as biocatalysts to biotransformation processes using solvent and non-aqueous systems.

Eco-Friendly Production Process of N-Hydroxysuccinimide from Succinic Anhydride (Succinic Anhydride로부터 N-Hydroxysuccinimide의 친환경 생산공정 개발)

  • Goo, Bon Suk;Baek, Jeong yeon;Park, Hwa In;Jung, In Chan;Kim, Woo-Sun
    • Clean Technology
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    • v.26 no.2
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    • pp.91-95
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    • 2020
  • A new eco-friendly synthetic method for N-hydroxysuccinimide (NHS), widely used in the pharmaceutical and fine chemical industries, is developed. Conventional synthesis method yields NHS of about 70% after its reaction with NH2OH to succinic acid. In this method, NHS can be obtained using low-cost succinic acid, but a great deal of solvents are required as an extraction method to purify NHS, while the work-up process is complicated, resulting in low yield. In addition, there is a safety risk due to the high reaction temperature for commercial production, and it is not economical due to the high cost of production from the generation of much waste because of an acid catalyst and the use of various solvents. In order to make up for this shortcoming, this study used succinic anhydride as a raw material under low temperature reaction and developed a new eco-friendly industrial synthesis method using isobutyl alcohol for a single solvent and non-catalytic reaction. The economic evaluation confirms that there is a cost reduction effect of about 20%. In the future, based on this result, studies may establish a commercial production technology through scale-up research and proceed with foreign technology transfer.

Screening of Effective Extraction Conditions for Increasing Antioxidant Activities from Fronds of Osmunda japonica (고비의 항산화활성 증가를 위한 효율적인 추출조건 탐색)

  • Shin, So-Lim;Lee, Cheol-Hee
    • Korean Journal of Plant Resources
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    • v.24 no.2
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    • pp.174-180
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    • 2011
  • This study was conducted to investigate the optimum condition of extraction from fronds of Osmunda japonica to increase antioxidant compounds and antioxidant activity. Powder (1 g) of lyophilized fronds were mixed with three different solvents (MeOH, 80% EtOH and water). Extraction was carried out using not only by immersion (room temp.), heating ($60^{\circ}C$) and stirring (200 rpm) for 6 h, but also by sonication in 42 kHz ultrasonic bath for 15, 30 and 45 min. Extracts were filtered, and adjusted up to 50 mL to determine contents of soluble solids, total polyphenols and total flavonoids. Antioxidant capacity was measured by radical scavenging activity of 0.15 mM DPPH (2,2-diphenyl-1-picrylhydrazyl) and 7.4 mM ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)] radical. Among the solvents, MeOH and 80% EtOH appeared to be effective for extraction. Extract obtained from sonication in MeOH for 15 min resulted high polyphenol contents (45.15 $mg{\cdot}g^{-1}$ db) and DPPH radical scavenging activity ($RC_{50}$= 0.35 $mg{\cdot}mL^{-1}$). The highest flavonoid contents was obtained from immersion or heating extraction with MeOH (38.10~38.10 $mg{\cdot}g^{-1}$ db). ABTS radical scavenging was high in same extraction with 80% EtOH ($RC_{50}$= 0.21~0.22 $mg{\cdot}mL^{-1}$). Altogether, our results indicate that the extraction using ultrasonic bath with MeOH as a solvent (for 15~30 minutes) was the most effective way not only for increasing various antioxidant activities but also for saving labor and time in case of fronds of Osmunda japonica.