Extraction and isolation of indole alkaloids from Tabemaemontana catharinensis A.DC: Technical and economical analysis

In the present work, the technical and economical analysis of extraction and isolation of indole alkaloids from Tabernaemontana catharinensis is presented. The extraction was carried out using supercritical CO2 as solvent and ethanol as cosolvent (5%, v/v). The global yield isotherms were determined at 35 and 45 degrees C for pressures of 150-350 bar. The mass transfer rate for the constant extraction rate period (CER), the duration of the CER period, and the mass ratio of solute in the fluid phase at the bed outlet were calculated. The extraction curves were adjusted by Crank, Goto et al. and Esquivel et al. models. The economical analysis was carried out considering that the cost of manufacturing can be obtained in terms of the costs of investment, operational labor, raw material, waste treatment and utilities. The higher global yields were obtained at 350 bar (1.30 x 10(-2) and 1.54 x 10(-2) kg/kg, at temperatures of 35 and 45 degrees C, respectively). The Goto's model was able to quantitatively describe the experimental data. The cost of manufacturing the extracts obtained at 350 bar, 45 degrees C, using 5% (v/v) of ethanol was US$79.35 kg(-1) of extract. Using previous experimental data obtained at 300 bar, 55 degrees C, using 10$ 440.31 kg(-1) of alkaloids. (C) 2006 Elsevier B.V. All rights reserved.40223223

Supercritical fluid extraction of lycopene from tomato juice and characterization of its antioxidation activity

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)A new method to extract lycopene from tomato juice using supercritical CO(2) as solvent and without the need to dry the raw material is presented. To conduct the extraction, the tomato juice was subjected to cycles of centrifugation followed by rinsing with absolute ethanol to partially remove the water present in the solid part of the juice. The influence of the temperature and pressure on the extraction efficiency and on the extract antioxidant activity was studied using a factorial experimental design. The extraction efficiency varied from 7.7% to 76.7% and only extraction temperature had a statically significant effect on the process. The reversed phase HPLC analysis showed that lycopene is the major compound of the extract. The extract that presented higher antioxidant activity was obtained at 40 degrees C and 350 bar with 12.7 mmol L(-1) Trolox/g of extract using the DPPH radical scavenging method and 61.3 mmol L(-1) Trolox/g of extract using the rubrene singlet oxygen quenching method. (C) 2010 Elsevier B.V. All rights reserved.542159164Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)FAPESP [2006/04243-1

Production of biodiesel from castor oil using sub and supercritical ethanol: Effect of sodium hydroxide on the ethyl ester production

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The biodiesel obtained by the reaction of castor oil with ethanol under sub and supercritical condition (200-350 degrees C at endogenous pressure) using small amounts of sodium hydroxide (NaOH) as catalyst was studied. The influence of the operating variables such as temperature, reaction time, ethanol:oil molar ratio and catalyst concentration (when used) on the reaction yield was evaluated using a statistical design of experiments along with the surface response methodology for both the catalytic and non-catalytic processes. It was observed that using only 0.1% wt of NaOH for the catalytic process, amount smaller than the necessary to neutralize the castor oil, it was possible to obtain high yields. The maximum ethyl ester yield reached was 98.9% for the catalytic process and 56.2% for the non-catalytic process. Additionally, the reaction kinetic was determined and it was found that a pseudo first order model represents the overall reaction. Activation energies were calculated from the Arrhenius equation for both processes. (C) 2013 Elsevier B.V. All rights reserved.83124132Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Supercritical fluid extraction of fatty acids and carotenoids from the microalgae Spirulina maxima

The supercritical fluid extraction of fatty acids and carotenoids from the microalgae Spirulina maxima with carbon dioxide was studied. The effects of pressure and temperature on the yield and chemical composition of the extracts were assessed. The experiments were conducted at temperatures of 20-70 degreesC and pressures of 15-180 bar. The solvent mass flow rate was 3.33 x 10(-5) kg/s. Statistical analysis showed that neither the temperature nor the pressure significantly affected the total yield, but both the temperature and the pressure affected the extraction rate, and the effect of the temperature prevailed over that of the pressure. The extracts were rich in essential fatty acids and carotenes, and at 100 bar and 45 degreesC the extract contained no carotenes. Temperatures larger than 50 degreesC degraded the carotenes, as expected. The model of Goto et al. described the overall experimental extraction curves quite well.41123012301

Supercritical fluid extraction from rosemary (Rosmarinus officinalis): Kinetic data, extract's global yield, composition, and antioxidant activity

In the present work the global yields isotherms and the overall extraction curves for the system rosemary (Rosmarinus officinalis) + CO2, the chemical composition and antioxidant activity of the extracts were determined. The experiments were performed in two supercritical extraction units. The following bed height to bed diameter ratios were used: 0.67, 1.34, 2.8, 5.6, and 8.4. The global yields were determined for the isotherms of 30 and 40 degrees C for pressures of 100-300 bar. The overall extraction curves were determined at 40 degrees C and 300 bar. Rosemary extracts were also obtained by hydrodistillation (volatile oil) and extraction with solvent, ethanol and hexane were used. The chemical compositions of the extracts were determined by gas chromatography; the contents of phenolic diterpenes (carnosoic and rosmarinic acids) were determined by UV spectrophotometry. The antioxidant activity was measured by the coupled reaction of beta-carotene and linolenic acid. The largest global yield (5% dry basis) was obtained at 40 degrees C and 300 bar. The major compounds detected in the extracts were camphor and 1,8-cineol. The long term antioxidant activity varied from 80% for the extract obtained at 150 bar and 30 degrees C to 95% for the extract obtained at 300 bar and 40 degrees C. The content of carnosoic acid was nine times larger for the extract obtained at 300 bar and 40 degrees C as compared to the volatile oil. The models of Crank, Esquivel et al., Goto et al., Martinez et al., Sovova, and Tan and Liou quantitatively fitted the overall extraction curves. Nonetheless, the mean square deviations for the models of Martinez et al., Crank, and Tan and Lion were approximately five times larger than that for the models of Goto et al., Sovova, and Esquivel et al. (c) 2005 Elsevier B.V. All rights reserved.35319720

Obtaining beta-caryophyllene from Cordia verbenacea de Candolle by supercritical fluid extraction

In the present work, the use of supercritical fluid extraction (SFE) to obtain beta-caryophyllene from Cordia verbenacea DC was studied. The assays were performed using a single-step SFE (1S-SFE) and a three-step SFE (3S-SFE). In view of the literature results for the biological activities of C. verbenacea, the assays for the 3S-SFE were conducted at 60 degrees C and pressures of 8, 20, and 30 MPa, while for the 1S-SFE, they were performed at 50 and 60 degrees C and pressures of 20 and 30 MPa. In the 3S-SFE, three samples of C. verbenacea extract were obtained. The purity of P-caryophyllene was 33% (extract's dry basis) for the fraction obtained at 8 MPa. The kinetics of supercritical CO(2) extraction was studied at the optimum operational conditions for global yield and anticancer activity (30 MPa/50 degrees C and 20 MPa/40 degrees C, respectively). The effect of bed height on the kinetic parameters of the SFE process was also investigated. Literature models fitted quantitatively the experimental extraction curves. (C) 2008 Elsevier B.V. All rights reserved.461273

Multicomponent model to describe extraction of ginger oleoresin with supercritical carbon dioxide

The kinetics of supercritical fluid extraction from vegetable raw materials in fixed beds was studied. The operational conditions used in the extraction of ginger oleoresin were pressures of 150, 200, and 250 bar, temperatures of 20, 30, and 40 degreesC, and a solvent flow rate of (5.6 +/- 0.3) X 10(-5) kg/s of CO2. A mathematical model obtained from the differential mass balance in the extraction bed was presented. This model considers the extract as a mixture of various groups of compounds, classified according to their chemical characteristics. The interfacial mass flux of each group of compounds was assumed to be described by one of the solutions of the logistic equation. The model was able to describe quite well the experimental results for ginger oleoresin extraction, considering the extract either as a single pseudocompound or as the sum of three groups of compounds. The overall extraction curves were fitted by both the proposed model and Sovova's model; the sum of square deviations was lower for the proposed model.4251057106

Supercritical fluid extraction of vetiver roots: A study of SFE kinetics

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The volatile oils from the Vetiveria zizanioides oil are particularly appreciated in perfume and cosmetic products but may also be used in the food industry as aroma and flavor agent. The objective of this work was to study the improvement over the conventional process on the quantity and quality of vetiver extracts recovered by supercritical technology (SFE). The pressure effect (100-300 bar) at 40 degrees C, and the influence of amount of ethanol used as cosolvent (0, 5 and 10%, v/v) were studied. Supercritical extraction process was compared to the hydrodistillation, based on vetiver extract quantity and quality; SFE extracts and presented khusimol contents of 14-29% over hydrodistillation and for SFE, the global yields and kinetic parameters obtained using 10% (v/v) of ethanol were statistically different from extraction using 0 and 5% of ethanol. The TLC and GC showed similar chemical profiles for SFE and HID, but were aware some compounds that were observed by TLC just during the t(CER) region. Mathematical modeling was performed for vetiver kinetics obtained by SFE + cosolvent and Sovova model showed the best adjusts for all curves. (C) 2008 Elsevier B.V. All rights reserved.472200208Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)CAPES [424/03]CNPq [472512/2004-8

Towards in situ fluorescence spectroscopy and microscopy investigations of asphaltene precipitation kinetics

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)We perform a spectroscopic analysis of asphaltene in solution and in crude oil with the goal of designing an optical probe of asphaltene precipitation inside high-pressure cells. Quantitative analysis of steady-state spectroscopic data is employed to identify fluorescence and Raman contributions to the observed signals. Time-resolved fluorescence spectroscopy indicates that fluorescence lifetime can be used as a spectroscopic probe of asphaltene in crude oil. Quantitative confocal laser-scanning microscopy studies of asphaltene in n-heptane are used to calculate particle-size distributions as a function of time, both at the sample surface and asphaltene interior. The resulting precipitation kinetics is well described by stochastic numerical simulations of diffusion-limited aggregation. Based on these results, we present the design and construction of an apparatus to optically probe the in situ precipitation of asphaltene suitable for studies inside high pressure cells. Design considerations include the use of a spatial light modulator for aberration correction in microscopy measurements, together with the design of epi-fluorescence spectrometer, both fiber-based and for remote sensing fluorescence spectroscopy. (C) 2013 Optical Society of America21253087430885Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Petrobras [P-02180]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)FAPESP [2011/20143-5, 2011/20144-1, 2012/14987-9, 2012/15018-0, 2008/10593-0]Petrobras [P-02180

Extraction of volatile oil from Croton zehntneri Pax et Hoff with pressurizedCO(2): solubility, composition and kinetics

Croton zehntneri Pax et Hoff is indigenous to the Northeastern of Brazil; is rich in (E)-anethole and is largely used in cooking to impart flavor to a variety of foods; is used in folk medicine to treat indigestion, insomnia, etc. In this work the volatile oil from C. zehntneri was extracted using pressurized CO2. Both kinetic and solubility experiments were performed at pressures of 66.7 and 78.5bar and temperatures from 10 to 28 degrees C. The composition of the volatile oil was determined using gas chromatography. The maximum solubility (2.83 x 10(-2) kg/kg) was observed at 15 degrees and 66.7 bar while the maximum global yield (3.4%, mass) was detected at 20 degrees C at the same pressure. The volatile oil was formed predominantly by (E)-anethole (73.6%, area), alpha-muurolene (7.51%), methyl chavicol or estragole (2.52%), germacrene D (2.11%) and small amounts of other terpenoidic compounds. The overall extraction curves were fitted by several models from the literature. The models that best described the overall extraction curves were the Goto et al., Martinez et al., and Sovova. (c) 2004 Elsevier Ltd. All rights reserved.69332533