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Supercritical Fluids

Zhi-Zhun Mo, Zhi-Xiu Lin, Zi-Ren Su, Lin Zheng, Hui-Lin Li, Jian-Hui Xie, Yan-Fang Xian, Tie-Gang Yi, Shui-Qing Huang, Jian-Ping Chen
Angelica sinensis (AS, Danggui in Chinese) is an important herbal component of various traditional formulae for the management of asthenia and its tonic effects. Although AS has been shown to ameliorate cognitive damage and nerve toxicity in D-galactose (D-gal)-elicited senescent mice brain, its effects on liver and kidney injury have not yet been explored. In this work, mice were subjected to hypodermic injection with D-gal (200 mg/kg) and orally gavaged with AS (20, 40, or 80 mg/kg) once a day for 8 successive weeks...
August 15, 2018: Journal of Medicinal Food
Valery Isidorov, Łukasz Szoka, Jolanta Nazaruk
Birch buds (Gemmae Betulae) are widely used in Russian and Chinese traditional medicine mainly as a diuretic and diaphoretic agent but also as an antiseptic, anti-inflammatory and analgesic. Despite the long history of therapeutic use of birch buds in folk medicine, the existing information on their chemical composition and pharmacological effects is insufficient. This circumstance warrants further study of the chemistry and pharmacology of birch buds. The present study was designed to investigate (a) the chemical composition of buds from two species of white birch and (b) the in vitro cytotoxic effect of extracts from these sources on selected tumour cells...
2018: PloS One
Luca Campone, Rita Celano, Anna Lisa Piccinelli, Imma Pagano, Sonia Carabetta, Rosa Di Sanzo, Mariateresa Russo, Elena Ibañez, Alejandro Cifuentes, Luca Rastrelli
Food industry produces a large amount of onion wastes. Due to the high amount of bioactive compounds in onion by-products an idea for their reuse, could be use them as source of high-value functional and health ingredients. In this study, outer dry layers of coppery onion "Ramata di Montoro" were used as source of bioactive compounds. Firstly, the chemical profile of secondary metabolites of exhaustive extract, obtained by ultrasound assisted extraction was established by UHPLC-UV-HRMS/MS analysis...
December 15, 2018: Food Chemistry
Ioannis J Stavrou, Atalanti Christou, Constantina P Kapnissi-Christodoulou
Carob (Ceratonia Siliqua L., tree of the pea family Fabaceae) and its products have recently attracted great interest due to their polyphenolic composition. This review summarizes the polyphenolic compounds that are contained in different carob parts (leaves, pod, seeds, barks) and products (syrup, flour, fiber). It also states the main differences of polyphenolic composition due to environmental and natural reasons, such as region, variety, and gender, and due to the processes used for preparation, extraction and analysis...
December 15, 2018: Food Chemistry
Yilun Yan, Jun Fan, Dong Guo, Yuemei Lin, Yecai Lai, Tai Wang, Hao Gao, Xinsheng Yao, Weiguang Zhang
Semi-preparative separation of lenalidomide has been performed through supercritical fluid chromatography. In regard to retention and resolution of lenalidomide, effects of chromatographic conditions, such as chiral stationary phases, organic co-solvents, mobile phases, and column temperature, have been studied in detail. Amylose tris(3, 5-dimethylphenylcarbamate)-coated and the single-urea-bound β-cyclodextrin chiral stationary phases exhibited good separation performances for lenalidomide in the CO2 -methanol mixture...
August 10, 2018: Journal of Separation Science
Marie-Paule Bassez
An alternative hypothesis for the origin of the banded iron formations and the synthesis of prebiotic molecules is presented here. I show the importance of considering water near its supercritical point and at alkaline pH. It is based on the chemical equation for the anoxic oxidation of ferrous iron into ferric iron at high-subcritical conditions of water and high pH, that I extract from E-pH diagrams drawn for corrosion purposes (Geophysical Research Abstracts Vol 15, EGU2013-22 Bassez 2013, Orig Life Evol Biosph 45(1):5-13, Bassez 2015, Procedia Earth Planet Sci 17, 492-495, Bassez 2017a, Orig Life Evol Biosph 47:453-480, Bassez 2017b)...
August 8, 2018: Origins of Life and Evolution of the Biosphere
Ranjith Kumar Kankala, Biao-Qi Chen, Chen-Guang Liu, Han-Xiao Tang, Shi-Bin Wang, Ai-Zheng Chen
In recent years, the supercritical fluid (SCF) technology has attracted enormous interest from researchers over the traditional pharmaceutical manufacturing strategies due to the environmentally benign nature and economically promising character of SCFs. Among all the SCF-assisted processes for particle formation, the solution-enhanced dispersion by supercritical fluids (SEDS) process is perhaps one of the most efficient methods to fabricate the biomaterials and pharmaceutical compounds at an arbitrary gauge, ranging from micro- to nanoscale...
2018: International Journal of Nanomedicine
M Acosta, F X Passelègue, A Schubnel, M Violay
Earthquakes result from weakening of faults (transient decrease in friction) during co-seismic slip. Dry faults weaken due to degradation of fault asperities by frictional heating (e.g. flash heating). In the presence of fluids, theoretical models predict faults to weaken by thermal pressurization of fault fluid. However, experimental evidence of rock/fluid interactions during dynamic rupture under realistic stress conditions remains poorly documented. Here we demonstrate that the relative contribution of thermal pressurization and flash heating to fault weakening depends on fluid thermodynamic properties...
August 6, 2018: Nature Communications
Davy Guillarme, Jean-Luc Veuthey
No abstract text is available yet for this article.
July 31, 2018: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Fleur H M van Zelst, S G J Bas van Meerten, P Jan M van Bentum, Arno P M Kentgens
By coupling supercritical fluid chromatography (SFC) and nuclear magnetic resonance (NMR) in-line, a powerful analytical method arises, that enables chemically specific analysis of a broad range of complex mixtures. However, during chromatography, the compounds are diluted in the mobile phase, in this case supercritical CO2 (scCO2 ), often resulting in concentrations that are too low to be detected by NMR spectroscopy or at least requiring excessive signal averaging. We present a hyphenated SFC-NMR set-up with an integrated approach for concentrating samples in-line, which are diluted in scCO2 during chromatography...
August 6, 2018: Analytical Chemistry
Martin Enmark, Emelie Glenne, Marek Leśko, Annika Langborg Weinmann, Tomas Leek, Krzysztof Kaczmarski, Magnus Klarqvist, Jörgen Samuelsson, Torgny Fornstedt
We investigated and compared the robustness of supercritical fluid chromatography (SFC) separations of the peptide gramicidin, using either isocratic or gradient elution. This was done using design of experiments in a design space of co-solvent fraction, water mass fraction in co-solvent, pressure, and temperature. The density of the eluent (CO2 -MeOH-H2 O) was experimentally determined using a Coriolis mass flow meter to calculate the volumetric flow rate required by the design. For both retention models, the most important factor was the total co-solvent fraction and water mass fraction in co-solvent...
September 21, 2018: Journal of Chromatography. A
Seied Mahdi Pourmortazavi, Zahra Saghafi, Ali Ehsani, Mohammad Yousefi
Various innovations have so far been devised to extract cholesterol from foods. Achieving a supercritical fluid is perhaps one of the greatest human successes in the field of extraction from foodstuffs in last 2 decades. Supercritical fluid extraction (SFE) offers a rapid, environment-friendly and selective method for extracting cholesterol from foods. This review aims at investigating the application of supercritical fluids in extraction of cholesterol. Various factors affecting the SFE, collection systems, examples of cholesterol extraction and SFE benefits are some of the issues discussed in this study...
August 2018: Journal of Food Science and Technology
Jian Liu, Feng Ji, Fengming Chen, Wei Guo, Minli Yang, Shengxiong Huang, Feng Zhang, Yongsheng Liu
A rapid, simple and environmentally friendly supercritical fluid extraction and supercritical fluid chromatography coupled to mass spectrometry (SFE-SFC-MS/MS) method has been developed for the analysis of nine phenolic compounds in garlic. Through the optimization of the SFE parameters using response surface methodology (RSM), 15 phenolic compounds were successfully extracted at 50 °C in 9 min with the addition of 30% methanol using a method that was automatic, efficient, green and prevented oxidation...
July 20, 2018: Journal of Pharmaceutical and Biomedical Analysis
Abhijit Pawar, Shreya Thakkar, Manju Misra
Recent analysis of the published data reveals the increasing importance of nanotechnology in the field of drug delivery, especially due to easy modulation of drug release and targeting effect. Various conventional methods including nanoprecipitation, spray drying, solvent evaporation, supercritical fluid extraction and ionotropic gelation are well-explored for lab-scale production of nanoparticles and present their own advantages and limitations. Electrospraying a variant of electrospinning is a method based on the processing of polymeric solutions/melt under high electrical voltage to produce particles of desired nature; post optimization of process parameters...
July 24, 2018: Journal of Controlled Release: Official Journal of the Controlled Release Society
Tae Jun Yoon, Min Young Ha, Won Bo Lee, Youn-Woo Lee
The Frenkel line, a crossover line between rigid and nonrigid dynamics of fluid particles, has recently been the subject of intense debate regarding its relevance as a partitioning line of the supercritical phase, where the main criticism comes from the theoretical treatment of collective particle dynamics. From an independent point of view, this Letter suggests that the two-phase thermodynamics model may alleviate this contentious situation. The model offers new criteria for defining the Frenkel line in the supercritical region and builds a robust connection among the preexisting, seemingly inconsistent definitions...
July 31, 2018: Journal of Physical Chemistry Letters
Caroline West
Supercritical fluid chromatography (SFC), which employs pressurized carbon dioxide as the major component of the mobile phase, has been known for several decades but has faced a significant resurgence of interest in the recent years, thanks to the development of modern instruments to comply with current expectations in terms of robustness and sensitivity. This review is focused on the recent literature, specifically since the introduction of modern systems but in relation to older literature, to identify the changing trends in application domains...
July 27, 2018: Analytical and Bioanalytical Chemistry
Guang-Ping Lv, De-Jun Hu, Yan-Qing Zhou, Qing-Wen Zhang, Jing Zhao, Shao-Ping Li
A green and reliable method using supercritical fluid extraction (SFE) and molecular distillation (MD) was optimized for the separation and purification of standardized typical volatile components fraction (STVCF) from turmeric to solve the shortage of reference compounds in quality control (QC) of volatile components. A high quality essential oil with 76.0% typical components of turmeric was extracted by SFE. A sequential distillation strategy was performed by MD. The total recovery and purity of prepared STVCF were 97...
July 23, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Zarith Asyikin Abdul Aziz, Akil Ahmad, Siti Hamidah Mohd Setapar, Atlpug Karakucuk, Muhammad Mohsin Azim, David Lokhat, Mohammad Amjad Kamal, Ghulam Md Ashraf
BACKGROUND: Essential oils are liquid extracts from aromatic plants, which have numerous applications in multiple industries. There are a variety of methods used for the extraction of essential oils, with each method exhibiting certain advantages and determining the biological and physicochemical properties of the extacted oils. Essential oils from different plant species contain more than 200 constituents which are comprised of volatile and non-volatile components. The application of essential oils as antimicrobial, anticancer, anti-inflammatory and anti-viral agents are due to their effective and efficient properties, inter alia...
July 23, 2018: Current Drug Metabolism
Natividad Jurado-Campos, Azahara Carpio, Mohammed Zougagh, Lourdes Arce, Natalia Arroyo-Manzanares
This paper describes a pioneer on-line hyphenation between a supercritical fluid extraction (SFE) and an ion mobility spectrometry (IMS) detector through a Tenax TA sorbent trap as retention interface. By means of a simple design, taking advantage of both techniques, this new coupling allows us to extract and preconcentrate analytes and in a second step to determine them. As result, an increase in the accuracy of the analytical process was achieved by elimination of sample transfer from one device to another...
October 1, 2018: Talanta
Luís Padrela, Miguel A Rodrigues, Andreia Duarte, Ana M A Dias, Mara E M Braga, Hermínio C de Sousa
Low drug bioavailability, which is mostly a result of poor aqueous drug solubilities and of inadequate drug dissolution rates, is one of the most significant challenges that pharmaceutical companies are currently facing, since this may limit the therapeutic efficacy of marketed drugs, or even result in the discard of potential highly effective drug candidates during developmental stages. Two of the main approaches that have been implemented in recent years to overcome poor drug solubility/dissolution issues have frequently involved drug particle size reduction (i...
July 17, 2018: Advanced Drug Delivery Reviews
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