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High-pressure carbonation of mortar as a model for Recycled Concrete Aggregates. J Supercrit Fluids 2023. [DOI: 10.1016/j.supflu.2023.105932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
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Investigating the Aroma of Syrah Wines from the Northern Rhone Valley Using Supercritical CO 2-Dearomatized Wine as a Matrix for Reconstitution Studies. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:11512-11523. [PMID: 32924472 DOI: 10.1021/acs.jafc.0c04328] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
This study aimed to investigate the key compounds involved in the aroma of French Syrah wines from the northern Rhone valley from two vintages characterized by distinct climatic conditions. The volatile composition of the wines was assessed through the determination of 76 molecules. After identifying the best matrix and best model for aroma reconstitution studies, omission tests were conducted using the Pivot profile method. For both vintages, 35 molecules with odor activity values (OAVs) above 0.5 were identified. While remarkably high levels of 2-furfurylthiol (FFT) were reported in both wines, rotundone and 3-sulfanylhexanol (3SH) enabled the strongest discrimination between the two wines. Wine dearomatized using supercritical carbon dioxide (sCO2) was identified as the best matrix. The best models built using this matrix were composed of molecules with OAV > 5 and OAV > 10 highlighting that this dearomatization approach can be valuable to reconstitute the aroma of wine using a small number of molecules. For the cool vintage wine, the omission of rotundone and FFT had the greatest impact on the olfactive profile for nonanosmic and anosmic respondents to rotundone, respectively. 3SH, whose omission decreased the rating of the "fruity" attribute, was identified as the main contributor to the aroma of Syrah wine produced in the warm vintage.
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Controlling Solvation and Mass Transport Properties of Biobased Solvents through CO2 Expansion: A Physicochemical and Molecular Modeling Study. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.9b02218] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Lipase esterification in the Centrifugal Partition Reactor: Modelling and determination of the specific interfacial area. Biochem Eng J 2019. [DOI: 10.1016/j.bej.2019.01.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Kinetic Study of 5-Hydroxymethylfurfural Synthesis from Fructose in High Pressure CO2–Water Two-Phase System. Ind Eng Chem Res 2018. [DOI: 10.1021/acs.iecr.8b04694] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Rate-based simulation of a high pressure counter-current packed column for supercritical CO2 extraction of alcohol from dilute aqueous mixtures. J Supercrit Fluids 2018. [DOI: 10.1016/j.supflu.2018.01.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Resolution of 2-bromo-arylacetic acid ester by Yarrowia lipolytica lipase in water/supercritical CO2 two-phase systems. J Supercrit Fluids 2017. [DOI: 10.1016/j.supflu.2016.11.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Experimental Study and Modeling of Phase Equilibrium of the Methanol–Tripalmitin System: Application to Palm Oil Transesterification with Supercritical Methanol. Ind Eng Chem Res 2016. [DOI: 10.1021/acs.iecr.5b04588] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Comparison of different methods for extraction from Tetraclinis articulata: yield, chemical composition and antioxidant activity. Food Chem 2013; 141:3537-45. [PMID: 23993518 DOI: 10.1016/j.foodchem.2013.06.065] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Revised: 06/07/2013] [Accepted: 06/13/2013] [Indexed: 10/26/2022]
Abstract
In the present study, three techniques of extraction: hydrodistillation (HD), solvent extraction (conventional 'Soxhlet' technique) and an innovative technique, i.e., the supercritical fluid extraction (SFE), were applied to ground Tetraclinis articulata leaves and compared for extraction duration, extraction yield, and chemical composition of the extracts as well as their antioxidant activities. The extracts were analyzed by GC-FID and GC-MS. The antioxidant activity was measured using two methods: ABTS(•+) and DPPH(•). The yield obtained using HD, SFE, hexane and ethanol Soxhlet extractions were found to be 0.6, 1.6, 40.4 and 21.2-27.4 g/kg respectively. An original result of this study is that the best antioxidant activity was obtained with an SFE extract (41 mg/L). The SFE method offers some noteworthy advantages over traditional alternatives, such as shorter extraction times, low environmental impact, and a clean, non-thermally-degraded final product. Also, a good correlation between the phenolic contents and the antioxidant activity was observed with extracts obtained by SFE at 9 MPa.
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Enhancement of Poly(vinyl ester) Solubility in Supercritical CO2 by Partial Fluorination: The Key Role of Polymer–Polymer Interactions. J Am Chem Soc 2012; 134:11920-3. [DOI: 10.1021/ja304585d] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Continuous operation of lipase-catalyzed reactions in nonaqueous solvents: Influence of the production of hydrophilic compounds. Biotechnol Bioeng 2010; 56:232-7. [PMID: 18636628 DOI: 10.1002/(sici)1097-0290(19971020)56:2<232::aid-bit12>3.0.co;2-i] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In the field of biocatalysis in nonaqueous media, water has been identified as a crucial parameter which has to be carefully controlled. This article studies the continuous operation of a water-producing enzymatic reaction, here the esterification of oleic acid by ethanol in n-hexane catalyzed by Lipozyme(TM). The conversion decreased significantly over time, eventually coming to a lower steady-state level. This would be due to the accumulation of the produced water into the enzyme fixed-bed reactor, n-hexane being unable to evacuate this water out of the reaction vessel, because of the low polarity of this solvent. Therefore the conversion decreased until the produced water could be eliminated by the solvent achieving a steady state with a lower conversion. In supercritical carbon dioxide, a more hydrophilic solvent, steady state is at once obtained. This approach has been extended to reaction producing a hydrophilic compound, here glycerol during the transesterification between triolein and ethanol, and similar conclusions can be made. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 56: 232-237, 1997.
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Supercritical carbon dioxide processing of pyrethrum oleoresin and pale. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2003; 51:880-884. [PMID: 12568543 DOI: 10.1021/jf025998r] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Possible refining of crude hexane extract (CHE) from pyrethrum flowers and further refining of Pyrethrum Board of Kenya (PBK) pale product is investigated with both liquid and supercritical carbon dioxide. The experiments were carried out in a small pilot plant with a 200 mL extractor and three cyclonic separators in series. To understand the dynamics of pyrethrin extraction, CHE was extracted in a single step; pyrethrin concentration was found to be improved from 0.16 to 0.50 g/g. The effects of temperature and pressure on the quality of the extract were studied at 29 degrees C and 80 bar and at 40 degrees C and 100 bar. Liquid CO(2) processing (29 degrees C, 80 bar) yielded slightly better product quality. A comparison study of CHE and PBK pale processing with supercritical CO(2) (40 degrees C, 100 bar) showed that the final products were similar in terms of pyrethrin content. Extraction of both PBK pale and CHE in two steps with different operating conditions improved their purity.
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Esterification by immobilized lipase in solvent-free media: kinetic and thermodynamic arguments. Biotechnol Bioeng 2002; 78:313-20. [PMID: 11920447 DOI: 10.1002/bit.10224] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The aim of this study is to characterize, in solvent-free systems (SFS), the kinetic and thermodynamic performance of batch lipase-catalyzed esterification. SFS are compared to a conventional organic solvent, n-hexane. The esterification of oleic acid with ethanol was chosen as a model reaction. The TABEK (thermodynamic activity-based enzyme kinetics) approach was used to rationally analyze kinetics. Influence of the reaction medium on final conversions was also studied. Several factors, such as initial molar ratio of substrates, reactant availability, initial water content, and quantity of immobilized enzyme, were examined. Special attention was also turned to enzyme stability and reuse after reaction, this last item being a prerequisite in the development of industrial processes. SFS proved to be almost as efficient as n-hexane from a kinetic and thermodynamic point of view and offered a better volumetric production.
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Abstract
This work deals with the feasibility of achieving an extractive fermentation of 2-phenylethyl alcohol, the rose aroma, coupling fermentation with Kluyveromyces marxianus and supercritical carbon dioxide (SCCO2) extraction. The extractive process is, in this case, of special interest due to the strong yeast inhibition by 2-phenylethyl alcohol. First results confirmed that direct SCCO2 extraction is not possible, due to a drastic CO2 effect on cell viability. It is therefore necessary to perform cell separation prior to the extraction. Aroma extraction conditions from a synthetic mixture were then optimized, a pressure of 200 bar and a temperature in the range 35-45 degrees C being chosen. Under these conditions, the distribution coefficient Kd is 2 times higher than during the extraction using a conventional organic solvent, n-hexane. Using a simple model of aroma partition between aqueous and SCCO2 phases, the parameters of a continuous extraction from a synthetic broth were defined. The two substrates, glucose and phenylalanine, are not extracted whatever the conditions. As predicted by the model, more than 90% of 2-phenylethyl alcohol can be extracted, while the extraction of ethanol, the second main product, can be easily tuned with respect to operating conditions, as a function of its influence on the fermentation. Finally, the feasibility of the aroma recovery using two depressurization steps at the outflow of the extraction vessel was demonstrated; 97% of the extracted aroma was recovered, and a mass purity of 91% was achieved. Copyright 1999 John Wiley & Sons, Inc.
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Water activity control: a way to improve the efficiency of continuous lipase esterification. Biotechnol Bioeng 1998; 60:362-8. [PMID: 10099440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
During continuous lipase-catalyzed oleic acid esterification by ethanol in n-hexane, the oleic acid conversion, initially at 95%, decreases to 20% after 2 h. This decrease is caused by the accumulation of the water produced in the course of the reaction in the packed-bed reactor (PBR). In order to improve the PBR efficiency, it is necessary to evacuate the water produced. In this study, different approaches have been tested to control the water content in the PBR during continuous esterification. The first approach consisted in improving the water solubility by increasing the reaction medium polarity. The addition of polar additives to n-hexane, the use of more polar solvents, and the use of solvent-free reaction medium were tested as a means to favor the water evacuation from the PBR. First of all, the use ofn-hexane supplemented with acetone (3 M) or 2-methyl-2-propanol (1 M) enabled the conversion to be maintained at higher values than those obtained in pure n-hexane. The replacement of n-hexane by a more polar solvent, like the 5-methyl-2-hexanone, resulted in the same effect. In all cases, conversions at steady-state were always less than 95%, as obtained in pure n-hexane. This is explained by a decrease in the enzyme activity due to the increase in the medium polarity. Nevertheless, an increase in enzyme quantity allowed 90% conversion to be maintained during 1 week using 3 M acetone amended n-hexane. Good results (a steady-state conversion of about 80%) were obtained when esterification was carried out in a solvent-free reaction medium containing 2 M 2-methyl-2-propanol as a polar additive. The second approach consisted in the evaporation of the accumulated water by use of an intermittent airflow. Although this process did not enable constant esterification rate to be maintained, it did enable the initial conversion (95%) to be restored intermittently.
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Prediction of water adsorption curves for heterogeneous biocatalysis in organic and supercritical solvents. Chem Eng Sci 1997. [DOI: 10.1016/s0009-2509(96)00413-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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20
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Experimental and theoretical analysis of the chromatographic behaviour of protein purification fusions carrying charged tails. BIOSEPARATION 1995; 5:53-64. [PMID: 7537135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Poly(glutamic acid) tail consisting of 6 glutamate residues was fused to the N-terminus of Escherichia coli beta-galactosidase (beta-gal), by genetic engineering techniques. The wild-type and modified genes were expressed intracellularly and in soluble state in Escherichia coli, leading to the proteins respectively designated beta-gal2 and E6-beta-gal. Both enzymes were purified by affinity chromatography. The specific activity of purified E6-beta-gal was found to be comparable to the wild-type enzyme and its increased net charge was indicated by lon-Exchange Chromatography (IEC). The use of such a charged fusion for selective recovery of beta-gal from cell extract using IEC and Ion-Exchange Membrane Chromatography (IEMC) was explored. The additional charges enabled the separation factor to be increased about two-fold on both IEC and IEMC, but the IEMC step achieved a better throughput than the IEC step. The selectivity of recovery promoted by the charged tail was further analysed by processing the experimental data obtained in IEC with the Stoichiometric Displacement Model, a recent model very appropriate for the understanding of the retention of polymeric biomolecules on ion-exchangers. It was shown that E6-beta-gal had the same characteristic charge as beta-gal2 but that the binding constant to the ion-exchanger of the tagged beta-gal was 6 times greater than for the wild-type enzyme.
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Abstract
Supercritical carbon dioxide was used for bone delipidation. It appeared that this technology is very efficient since supercritical CO2 is able to diffuse into microporous solids much better than liquids and that it has a good solvent capacity for lipids. This extraction is the ideal first step of any bone processing because microporosity of bone tissue becomes much more accessible, which may enhance osteoconduction once implanted. Moreover, it is safe since it involves no toxic chemical and is potentially usable with allografts as well as xenografts.
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Geranyl acetate synthesis by lipase-catalyzed transesterification in supercritical carbon dioxide. Enzyme Microb Technol 1993. [DOI: 10.1016/0141-0229(93)90071-9] [Citation(s) in RCA: 116] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Preparative anion-exchange chromatography of soybean trypsin inhibitor: the alternative of column-overload methods. JOURNAL OF CHROMATOGRAPHY 1992; 584:115-20. [PMID: 1487511 DOI: 10.1016/0378-4347(92)80016-j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The objective of preparative separation is to purify the largest amount of material in the shortest time and at a minimum cost, i.e. to maximize throughout. One of the techniques for increasing throughput is to overload the column while maintaining purity and cycle time at the same level. This principle is applied in sample displacement mode chromatography, in which the column is overloaded with sample mixture until it is completely saturated. Soybean trypsin inhibitor was purified from a crude protein extract by this technique using an analytical anion-exchange column with small particle size (20 microns). The comparison of these results, using the criterion of throughput, with those derived from a conventional scale-up, using a 40-microns preparative column, led to the conclusion that the overloaded 20 microns column gave a higher throughput than the 40-microns column.
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Kinetics of geranyl acetate synthesis by lipase-catalysed transesterification in n-hexane. Enzyme Microb Technol 1992. [DOI: 10.1016/0141-0229(92)90154-g] [Citation(s) in RCA: 117] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
The kinetic of the esterification of oleic acid by ethanol catalyzed by immobilized lipase of Mucor miehei in n-hexane as a solvent has been completely studied. The kinetics of the reaction are suggested to agree with a Ping-Pong Bi Bi mechanism in which only inhibition by excess of ethanol has been identified. Values of all apparent kinetic parameters were computed. No evidence of any significant external diffusional limitation which could account for these values has been detected. Optimization of water content through distribution ratio of water between solvent and support was examined.
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