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Supercritical Fluids

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https://www.readbyqxmd.com/read/30513100/chemical-characterization-and-biological-activity-of-six-different-extracts-of-propolis-through-conventional-methods-and-supercritical-extraction
#1
Danielle Devequi-Nunes, Bruna Aparecida Souza Machado, Gabriele de Abreu Barreto, Jéssica Rebouças Silva, Danielle Figuerêdo da Silva, José Luiz Carneiro da Rocha, Hugo Neves Brandão, Valéria M Borges, Marcelo Andres Umsza-Guez
Propolis is a natural product with many demonstrated biological activities and propolis extract has been used in the food, pharmaceutical and cosmetics industries. Different works have showed the variations in the chemical composition, and consequently, on the biological activity of the propolis that are associated with its type and geographic origin. Due to this study evaluated propolis extracts obtained through supercritical extraction and ethanolic extraction (conventional) in three samples of different types of propolis (red, green and brown), collected from different regions in Brazil (state of Bahia)...
2018: PloS One
https://www.readbyqxmd.com/read/30508380/raman-thermometry-in-water-ethanol-and-ethanol-nitrogen-mixtures-from-ambient-to-critical-conditions
#2
Tobias Christopher Klima, Andreas Siegfried Braeuer
We present investigations into remote liquid temperature sensing with Raman spectroscopy using different evaluation methods for the OH stretching vibration band. Water, ethanol and ethanol saturated with nitrogen, all as liquids or liquid-like supercritical fluids, are pumped through a heated microcapillary system at elevated pressures. Raman spectra are recorded from the liquid inside the microcapillary and are evaluated with respect to the temperature sensitivity of the OH stretching vibration. The four approaches applied are (i) to evaluate the center position of the Raman OH-band, (ii) the integrated absolute difference spectrum, (iii) the intensity ratio of two regions of the OH-band, and (iv) the intensity ratio of two fitted Gaussian peaks...
December 3, 2018: Analytical Chemistry
https://www.readbyqxmd.com/read/30502128/comparative-assessment-on-the-extraction-of-carotenoids-from-microalgal-sources-astaxanthin-from-h-pluvialis-and-%C3%AE-carotene-from-d-salina
#3
REVIEW
M N Rammuni, Thilini U Ariyadasa, P H V Nimarshana, R A Attalage
Astaxanthin and β-carotene are important carotenoids used in numerous pharmaceutical and nutraceutical applications, owing to their vigorous antioxidant properties. The microalgal strains Haematococcus pluvialis and Dunaliella salina accumulate the highest quantities of astaxanthin and β-carotene (up to 7% and 13% dry weight respectively) and are therefore considered as sustainable feedstock for the commercial production of carotenoids. Thus, from an economical perspective, it becomes desirable to optimize recovery of carotenoids from microalgal cells...
March 30, 2019: Food Chemistry
https://www.readbyqxmd.com/read/30501785/micronization-of-ibuprofen-particles-using-supercritical-fluid-technology
#4
Tomáš Sosna, Marcel Mikeska, Ondčrej Dutko, Gražyna Simha Martynková, Katečrina Škrlová, Karla Čech Barabaszová, Katečrina Dčedková, Pavlína Peikertová, Daniela Plachá
Most of drugs are only slightly soluble in the circulatory system of the human body. This reduces the efficiency of their use and that is why new ways how to increase their solubility are investigated. One way to improve the solubility of the drug is to reduce its particle size. Conventional techniques such as crushing or grinding usually do not guarantee a narrow particle size distribution, which is required for pharmaceuticals. Application of supercritical fluids, especially of supercritical CO₂, seems to be convenient method for the preparation of pharmaceuticals submicron particles or nanoparticles...
May 1, 2019: Journal of Nanoscience and Nanotechnology
https://www.readbyqxmd.com/read/30501237/quantumness-and-state-boundaries-hidden-in-supercritical-helium-4-a-path-integral-centroid-molecular-dynamics-study
#5
Ayumi Takemoto, Kenichi Kinugawa
Isothermal-isobaric path integral centroid molecular dynamics simulations were conducted for fluid 4 He at more than 600 state points in the proximity of the critical point to reveal the detailed states and relevant quantumness underlying the supercritical state. Through intensive analyses of the thermodynamic, dynamic, and quantum properties, we revealed the hidden state boundaries that separate the liquid-like and gas-like states in the supercritical region of this fluid. The Widom line, defined as the locus of the maxima of isobaric heat capacity C P , is also the quantum boundary at which there are changes in the isobaric temperature-dependence of the quantum wavelength, λ quantum , i...
November 28, 2018: Journal of Chemical Physics
https://www.readbyqxmd.com/read/30497824/separation-of-enantiomers-of-native-amino-acids-with-polysaccharide-based-chiral-columns-in-supercritical-fluid-chromatography
#6
Emmanuelle Lipka, Anca-Elena Dascalu, Yasmine Messara, Eka Tsutsqiridze, Tivadar Farkas, Bezhan Chankvetadze
In this short communication preliminary results are reported on the separation of enantiomers of underivatized amino acids on polysaccharide-based chiral columns in sub/super-critical fluid chromatography (SFC). Racemic mixtures of 14 amino acids were used to evaluate the chiral recognition ability of 8 different polysaccharide-based chiral columns with coated or covalently immobilized chiral selectors. Among the studied columns, the one based on cellulose (3,5-dichlorophenylcarbamate) exhibited the most universal chiral recognition ability providing baseline resolution for the enantiomers of 10 studied amino acids...
November 22, 2018: Journal of Chromatography. A
https://www.readbyqxmd.com/read/30486940/potent-anti-proliferation-on-the-colon-cancer-cell-line-ht-29-of-liposomal-formulations-entrapped-with-semi-purified-job-s-tears-coix-lacryma-jobi-linn-fractions
#7
Aranya Manosroi, Mathukorn Sainakham, Masahiko Abe, Kenichi Sakai, Nuttanan Sinchaipanid, Worapaka Manosroi, Jiradej Manosroi
Liposomes, entrapped with Job's Tears fractions, were prepared by the supercritical carbon dioxide fluid (scCO₂) technique with and without sonication. Physical characteristics, which were the particle size, zeta potential, vesicular morphology, microviscosity and bioactivities including anti-proliferative, apoptotic and antioxidative activities of the S1L-S5L liposomal systems, were investigated. The potent anti-proliferative activity with the IC50 value of 4.44±2.31 ug/ml in a colon cancer cell (HT-29) was observed in the S5L...
April 1, 2019: Journal of Nanoscience and Nanotechnology
https://www.readbyqxmd.com/read/30483450/supercritical-fluid-extraction-effectively-removes-phthalate-plasticizers-in-spores-of-ganoderma-lucidum
#8
Pan Li, Zuan-Hao Liang, Zhuo Jiang, Ziyou Qiu, Bing Du, Yu-Bing Liu, Wen-Zhi Li, Li-Hao Tan
Phthalate plasticizers residue in food is a serious threat to public health. Spores of Ganoderma lucidum are easy to be contaminated with phthalates during collection and processing. In this study, supercritical fluid extraction (SFE) was performed to remove phthalates in spores of G. lucidum , and the effects on acid and peroxide values of spores' oil were also evaluated. The results showed SFE removed 100% of the residual di-iso-butyl phthalate, di- n -butyl phthalate and di-2-ethylhexyl phthalate in the spores of G...
December 2018: Food Science and Biotechnology
https://www.readbyqxmd.com/read/30470909/emerging-techniques-for-cell-disruption-and-extraction-of-valuable-bio-molecules-of-microalgae-nannochloropsis-sp
#9
REVIEW
Rui Zhang, Oleksii Parniakov, Nabil Grimi, Nikolai Lebovka, Luc Marchal, Eugène Vorobiev
Microalgae of Nannochloropsis sp. present valuable source of bio-molecules (pigments, lipids, proteins) that have nutritional potential for the prevention and treatment of human diseases. Moreover, some species of Nannochloropsis are the promising sources of biofuels and excellent candidates for the replacement of classical biofuel crops. This review describes and compares the efficiency of different conventional and novel techniques that can be used for cell disruption and recovery of bio-molecules from Nannochloropsis sp...
November 23, 2018: Bioprocess and Biosystems Engineering
https://www.readbyqxmd.com/read/30457137/disposable-silicon-glass-microfluidic-devices-precise-robust-and-cheap
#10
ZhenBang Qi, Lining Xu, Yi Xu, Junjie Zhong, Ali Abedini, Xiang Cheng, David Sinton
Si-glass microfluidics have long provided unprecedented precision, robustness and optical clarity. However, chip fabrication is costly (∼500 USD per chip) and in practice, devices are not heavily reused. We present a method to reduce the cost-per-chip by two orders of magnitude (∼5 USD per chip), rendering Si-glass microfluidics disposable for many applications. The strategy is based on reducing the area of the chip and a whole-chip manifolding strategy that achieves reliable high-pressure high-temperature fluid connectivity...
November 20, 2018: Lab on a Chip
https://www.readbyqxmd.com/read/30451874/a-novel-targeted-analysis-of-peripheral-steroids-by-ultra-performance-supercritical-fluid-chromatography-hyphenated-to-tandem-mass-spectrometry
#11
Neil de Kock, Santosh R Acharya, S J Kumari A Ubhayasekera, Jonas Bergquist
Ultra-performance supercritical fluid chromatography-tandem mass spectrometry (UPSFC-MS/MS) is an alternative method for steroid analysis. Continuous development of analytical methodologies for steroid profiling is of major importance in the clinical environment to provide useful and more comprehensive data. The aim of this study was to identify and quantify a large number of endogenous steroids from the four major classes (estrogens, androgens, progestogens and corticosteroids) simultaneously within a short analytical time...
November 19, 2018: Scientific Reports
https://www.readbyqxmd.com/read/30445845/antioxidant-potential-and-phytochemical-composition-of-extracts-obtained-from-phyllanthus-phillyreifolius-by-different-extraction-methods
#12
Dovilė Grauzdytė, Audrius Pukalskas, Chaker El Kalamouni, Petras Rimantas Venskutonis
Phyllanthus phillyreifolius (Euphorbiaceae), poorly studied plant species, was fractionated using conventional and high pressure extraction techniques such as supercritical fluid and pressurized liquid extractions. Lipophilic substances were extracted with n-hexane and supercritical CO2 with or without co-solvent ethanol, meanwhile higher polarity fractions were recovered with acetone and 70% ethanol. Antioxidant potential was assessed by various chemical assays, which revealed that 70% ethanol was the most effective solvent for recovery of antioxidants...
November 16, 2018: Natural Product Research
https://www.readbyqxmd.com/read/30424551/state-of-the-art-extraction-methodologies-for-bioactive-compounds-from-algal-biome-to-meet-bio-economy-challenges-and-opportunities
#13
REVIEW
Juan Eduardo Sosa-Hernández, Zamantha Escobedo-Avellaneda, Hafiz M N Iqbal, Jorge Welti-Chanes
Over the years, significant research efforts have been made to extract bioactive compounds by applying different methodologies for various applications. For instance, the use of bioactive compounds in several commercial sectors such as biomedical, pharmaceutical, cosmeceutical, nutraceutical and chemical industries, has promoted the need of the most suitable and standardized methods to extract these bioactive constituents in a sophisticated and cost-effective manner. In practice, several conventional extraction methods have numerous limitations, e...
November 12, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/30424515/poly-urethane-acrylate-aerogels-via-radical-polymerization-of-dendritic-urethane-acrylate-monomers
#14
Maria Papastergiou, Aspasia Kanellou, Despoina Chriti, Grigorios Raptopoulos, Patrina Paraskevopoulou
The purpose of this work was to investigate the effect of multifunctionality on material properties of synthetic polymer aerogels. For this purpose, we present the synthesis and characterization of monolithic dendritic-type urethane-acrylate monomers based on an aliphatic/flexible (Desmodur N3300), or an aromatic/rigid (Desmodur RE) triisocyanate core. The terminal acrylate groups (three at the tip of each of the three branches, nine in total) were polymerized with 2,2'-azobis(isobutyronitrile) (AIBN) via free radical chemistry...
November 12, 2018: Materials
https://www.readbyqxmd.com/read/30411012/combining-breath-figures-and-supercritical-fluids-to-obtain-porous-polymer-scaffolds
#15
Marta Castaño, Enrique Martinez-Campos, Mercedes Pintado-Sierra, Carolina García, Helmut Reinecke, Alberto Gallardo, Juan Rodriguez-Hernandez, Carlos Elvira
Supercritical fluids technology is a clean methodology to foam polymeric materials. However, this technique provides only the formation of inner porosity, whereas the so-called skin layer is commonly observed at the polymer surface. This article describes a new method for the preparation of outer and inner porous poly(ε-caprolactone) (PCL) scaffolds by combination of supercritical CO2 (SCCO2 ) foaming and the breath figures technique. In the first step, experiments with a SCCO2 reactor were performed at 35-45 °C, 100-250 bar, and 1-20 min depressurization time...
October 31, 2018: ACS Omega
https://www.readbyqxmd.com/read/30409077/potential-benefits-of-near-critical-and-supercritical-pre-treatment-of-lignocellulosic-biomass-towards-anaerobic-digestion
#16
Jenny Carolina Rosero-Henao, Beatriz Egerland Bueno, Raquel Souza, Rogers Ribeiro, Alessandra Lopes de Oliveira, Catarina Abdalla Gomide, Tamara Maria Gomes, Giovana Tommaso
Vegetable crop residues, such as sugarcane bagasse (SCB), despite their limited biodegradability, are potential materials for anaerobic processes because of their low cost, high availability, and sugar content. The difficulty of biodegrading this type of material is primarily related to its chemical composition and to the complex interactions between its compounds (cellulose, hemicelluloses, and lignin). Thus, the following supercritical and near critical carbon dioxide (CO2 ) pre-treatments were evaluated with and without the addition of sodium hydroxide (NaOH): (i) 40°C/70 kgf·cm-2 ; (ii) 60°C/200 kgf·cm-2 ; and (iii) 80°C/200 kgf·cm-2 , aiming to enhance the anaerobic biodegradability of SCB...
November 9, 2018: Waste Management & Research
https://www.readbyqxmd.com/read/30402134/immunostimulatory-effect-of-zanthoxylum-schinifolium-based-complex-oil-prepared-by-supercritical-fluid-extraction-in-splenocytes-and-cyclophosphamide-induced-immunosuppressed-rats
#17
Hak Yong Lee, Young Mi Park, Yang Hee Lee, Yang Gyu Kang, Hyang Man Lee, Deuk Seon Park, Hye Jeong Yang, Min Jung Kim, Young-Rae Lee
Complex oil of Zanthoxylum schinifolium and Perilla frutescens seed (ZPCO) is used as a traditional medicine due to its pharmacological activities. The aim of this study was to investigate the immunostimulatory effect of ZPCO in isolated splenocytes as well as in an immunosuppressed rat model, which was generated via oral administration of cyclophosphamide. Notably, our results showed that ZPCO exerted an immunity-enhancing effect both in vitro and in vivo . Specifically, ZPCO treatment enhanced the viability and inflammatory cytokine production of splenocytes and NK cell activity in vitro...
2018: Evidence-based Complementary and Alternative Medicine: ECAM
https://www.readbyqxmd.com/read/30401538/application-and-enantiomeric-residue-determination-of-diniconazole-in-tea-and-grape-and-apple-by-supercritical-fluid-chromatography-coupled-with-quadrupole-time-of-flight-mass-spectrometry
#18
Xinzhong Zhang, Yuechen Zhao, Xinyi Cui, Xinru Wang, Huishan Shen, Zongmao Chen, Chun Huang, Narendra Meruva, Li Zhou, Fang Wang, Luchao Wu, Fengjian Luo
A chiral separation and residue determination method for diniconazole enantiomers in tea, apple, and grape was developed and validated by supercritical fluid chromatography coupled with quadrupole-time-of-flight mass spectrometry (SFC-Q-TOF/MS). The two diniconazole enantiomers were separated on a Chiral CCA column, and the chromatographic conditions (mobile phase proportion and modifier, column temperature, backpressure, and auxiliary solvent) were optimized. The optimal SFC-Q-TOF/MS conditions were selected as a mobile phase of CO2 /isopropanol (IPA) (v/v, 96/4), flow rate at 2...
October 31, 2018: Journal of Chromatography. A
https://www.readbyqxmd.com/read/30400304/extraction-of-astaxanthin-and-lutein-from-microalga-haematococcus-pluvialis-in-the-red-phase-using-co%C3%A2-supercritical-fluid-extraction-technology-with-ethanol-as-co-solvent
#19
Antonio Molino, Sanjeet Mehariya, Angela Iovine, Vincenzo Larocca, Giuseppe Di Sanzo, Maria Martino, Patrizia Casella, Simeone Chianese, Dino Musmarra
Astaxanthin and lutein, antioxidants used in nutraceutics and cosmetics, can be extracted from several microalgal species. In this work, investigations on astaxanthin and lutein extraction from Haematococcus pluvialis ( H. pluvialis ) in the red phase were carried out by means of the supercritical fluid extraction (SFE) technique, in which CO₂ supercritical fluid was used as the extracting solvent with ethanol as the co-solvent. The experimental activity was performed using a bench-scale reactor in semi-batch configuration with varying extraction times (20, 40, 60, and 80 min), temperatures (50, 65, and 80 °C) and pressures (100, 400, and 550 bar)...
November 3, 2018: Marine Drugs
https://www.readbyqxmd.com/read/30400271/essential-oils-from-humulus-lupulus-scco%C3%A2-extract-by-hydrodistillation-and-microwave-assisted-hydrodistillation
#20
Katarzyna Tyśkiewicz, Roman Gieysztor, Marcin Konkol, Jan Szałas, Edward Rój
Two different extraction methods were used for a comparative study of essential oils obtained from the Humulus lupulus scCO₂ (sc-supercritical) extract: microwave-assisted hydrodistillation (MAHD) and conventional hydrodistillation (HD). As a result, the best conditions for the maximum essential oil production were determined for the MAHD method at 335 W microwave power for 30 min at water to raw material ratio of 8:3. The obtained essential oils were enriched in β-myrcene in the amount of 74.13%⁻89.32% (wt%)...
November 3, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
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