The use of modifiers in supercritical fluid chromatography and extraction has become quite common due to the inability of pure carbon dioxide alone to solvate many of the compounds of interest. The effects of modifiers in supercritical fluid chromatography have been more thoroughly studied than the effects of modifier in supercritical fluid extraction. The effects of modifier on trapping efficiencies for off-line supercritical fluid extraction have been evaluated in this work. Sorbent and solid phase traps were investigated with pure carbon dioxide in order to determine the effect of stationary phase identity, pretreatment, and rinse solvent on the recoveries of a test mixture of compounds of varying vapor pressure and molecular weight. The solid phase traps, which were polyethylene frits, performed as well as the sorbent traps in most cases, and significantly better than the sorbent traps in many cases. The ability to cool these traps to -20°C allowed for efficient trapping of volatile compounds without the benefit of sorptive interactions. Sorbent and solid phase traps were then studied with the addition of 1%, 2%, 4%, and 8% methanol to the mobile phase. The sorbent trap explored consisted of 40 µm ODS packing material, while the solid phase trap consisted of 100 yum stainless steel beads. In this work trap temperatures ranged from 5-80°C. It was found that trap temperature, modifier concentration, and trap type influenced recoveries of the test mixture components. Applications of these solid phase and sorbent traps explored were the extraction of polychlorinated biphenyls from river sediment and the extraction of the active components from a drug formulation. The separation of some compounds of pharmaceutical interest was also explored, where the addition of modifier, and in some cases an additive, was required to elute compounds from the chromatographic column. / Ph. D.

In this work the Supercritical Fluid Extraction (SFE) and detection of sorbed metals in contaminated soils is explored. Iron containing samples were spiked onto sea sand and extracted with Supercritical Fluid CO₂. On-line detection was accomplished by decompressing the SF-CO₂ and analyte into a microwave induced plasma, whereby the resulting Iron atomic emission signal was quantified. This dissertation reports the first successful coupling of SFE and Microwave Induced Plasma - Atomic Emission Detection (MIP-AED) for the on-line analysis of sorbed metal contaminants. The on-line analysis was accomplished with a novel SFE-MIP interface design. Experiments involving the on-line extraction and detection of ferrocene spiked sea sand were very promising, in that unity of extraction and detection was achieved with this nonpolar compound. Percent recovery was greatly reduced when the on-line extraction of Iron III Trifluoroacetylacetonate (FeTFA) was attempted. Off-line extraction studies were performed to establish the optimum conditions necessary to effect the SFE of the following Iron III complexes: Iron III Acetylacetonate (FeAcac) and Iron III Trifluoroacetylacetonate. The greatest recovery (55.85 0/0) was achieved with Supercritical Fluid-CO₂ under the following conditions: 60°C, 150 atm, 20 minute static extraction followed by 20 minute dynamic extraction. The extraction vessel contained 0.250 mg iron complex, 20 μL HPLC grade methanol, and 20 μL deionized water. Trapping of the analyte was achieved by decompressing the SF-CO₂ and analyte in 10 mL of HPLC grade methanol held at O°C. / Ph. D.

Supercritical fluid (SF) technologies are being investigated extensively by the food industry for a variety of applications. Carbon dioxide in the supercritical state is of particular interest to the food industry due to its extremely low toxicity in comparison with organic solvents. Three applications of chromatography or extraction employing SFs in the analysis of food components and natural products were investigated. These applications related to carbohydrate, lipid, and coumarin derivative analyses. The peracetylated nitrogen derivatives of carbohydrates were analyzed by supercritical fluid chromatography (SFC) with flame ionization detection (FID), Fourier-transform infrared (FT-IR) detection, and mass spectrometry (MS) detection. Although reports in the literature indicated that only one derivatized component was detected under GC conditions, the SFC analysis of peracetylated aldonitrile derivatives of monosaccharides resulted in detection of multiple reaction products. The identification of the peracetylated nitrile and acyclic oxime was accomplished using both SFC/FT-IR and SFC/MS. The spectroscopic data indicated that an additional reaction product was a peracetylated cyclic oxime. The data was not conclusive enough to determine if the structure contained a pyranose or furanose ring. Changes in chemical composition of vegetable oils due to processing were observed employing SFC/FT-IR. Refined soybean oil and soybean oil that was hydrogenated with a NI or a Ni-S catalyst were analyzed. SFC/FT-IR provided an opportunity to determine the extent of unsaturation and isomerization in a single analysis. The C-H deformation of trans R₁HC=CHR₂ groups was observed at 972 cm⁻¹. The double bond in the cis configuration was evident by absorptions above 3000 cm⁻¹l. On-line FT-IR spectra of triacylglycerols and free fatty acids readily revealed conversion to trans isomers in those samples that were hydrogenated with the Ni-S. Quantitation was not possible due to the incomplete resolution of the cis and trans isomers present in the hydrogenated samples. Apparent threshold densities were determined for a series of coumarin derivatives using a supercritical fluid chromatograph with a flame ionization detector. The extraction cell was a LC stainless steel precolumn. Milligram quantities of the model compounds were extracted. Functionality, extraction temperature, and matrix affected the measured threshold densities of the compounds. The addition of two hydroxyl groups onto the coumarin structure caused the compound to be unextractable at 60°C and densities up to 0.90 g/mL. For those compounds that were completely extracted, coumarin, 7-methoxycoumarin, 3-phenylcoumarin, and psoralen, the apparent threshold density increased with increasing melting point. The melting or decomposition points of those compounds that were partially extracted ranged between 200 and 240°C. For those compounds that were not extracted, under the constraints of the experiment, the melting or decomposition points were greater than 240°C. A higher extraction temperature resulted in a lower threshold density. Corn starch was found to be a noninteractive matrix. / Ph. D.

<p>U radu su prikazani eksperimentalni rezultati natkritične ekstrakcije etarskog ulja bobica<br />kleke (<em>Juniperus communis</em> L.) i ulja iz semena uljane tikve golice (<em>Cucurbita pepo</em> L.). Ispitan je uticaj pritiska, temperature, stepena usitnjenosti čestica i protoka natkritičnog<br />ugljendioksida na promenu prinosa ulja sa vremenom. U cilju poređenja, usitnjeno seme uljane tikve ekstrahovano je i u ekstraktoru većih dimenzija, NOVA-SWISS, High<br />pressure extraction plant, kao i heksanom i petroletrom u ekstraktoru tipa Sokslet.<br />Praćena je i promena kvaliteta ekstrakata sa vremenom: u etarskom ulju kleke, GC-FID i GC-MS metodama, određen je relativni sadržaj 50 terpenskih jedinjenja i sve komponente ulja su svrstane u 5 osnovnih grupa (monoterpene, seskviterpene, oksidovane monoterpene, oksidovane seskviterpene i ostale komponente). U tikvinom ulju ekstrahovanom natkritičnim ugljendioksidom određen je masnokiselinski sastav GC-MS analizom, sadržaj tokoferola HPLC analizom, sterola i skvalena GC-MS metodom. Određeni su uslovi koji favorizuju ekstrakciju ispitanih jedinjenja za obe sirovine. Dat je dateljan prikaz matematičkih modela koji se koriste za opisivanje natkritične ekstrakcije etarskih ulja i masnih ulja, počev&scaron;i od najop&scaron;tijeg modela koji uključuje diferencijalne bilanse mase za rastvorak u masi natkritičnog fluida, u fluidu unutar pora čestica usitnjenog matrijala i u čvrstoj fazi, koji se uvođenjem određenih pretpostavki pojednostavljuje i svodi na modele koji su izabrani da budu ispitani u okviru ovoga rada. Ispitani su modeli kreireni po analogiji sa hlađenjem vrele kugle u masi fluida, tj. modeli tipa jedne sfere i to: Model jedne sfere-1 (MJS-1), koji pored uticaja koeficijenta efektivne difuzije ulja u materijalu na brzinu prenosa mase uzima u obzir uticaj koeficijenta prenosa mase kroz film natkritičnog fluida oko čestice, pri čemu je njegova vrednost procenjena preko postojećih korelacija; MJS-1 (2 par), u kome je spolja&scaron;nji koeficijent prenosa mase uzet kao drugi prilagodljiv parametar modela; MJS-2, gde je koeficijent efektivne difuzije jedini prilagođeni parametar, Model karakterističnog vremena i pro&scaron;ireni model klipnog toka koji je predložila Sovov&aacute;. Za modelovanje natkritične ekstrakcije ulja semena tikve kori&scaron;ćen je i kombinovani model Honga i sar. Softverskim paketima Mathcad 2001 Professional i Solver dodatka unutar Microsoft Excel 2003, određeni su parametri ispitanih modela u cilju najboljeg slaganja modela sa ekperimentalnim podacima. Za obe ispitane sirovine, među ispitanim modelima, izabrani su modeli koji najbolje opisuju njihovu ekstrakciju natkritičnim ugljendioksidom. Pro&scaron;ireni model klipnog toka koji je predložila Sovov&aacute; pokazao se podjednako dobrim za modelovanje natkritične ekstrakcije obe sirovine i ne&scaron;to bolji od ostalih primenjenih modela.</p> / <p>This study provides results of supercritical carbon dioxide (SCCO₂) extraction of juniper berries (<em>Juniperus communis</em> L.) and pumpkin seeds (<em>Cucurbita pepo</em> L. convar.&nbsp;<em>citrullina</em>) in a laboratorysupercritical fluid extraction apparatus. The influence<br />of pressure, temperature, particle size and carbon dioxide flow on the extraction kinetics of pumpkin seed oil and juniper berry essential oil was studied. Ground pumpkin seeds were also extracted with supercritical carbon dioxide in NOVA-SWISS, High Pressure Extraction Plant, and with hexane and petroleum ether in a laboratory Soxhlet extractor. This work was also aimed to investigate the evolution of the composition of juniper fruit supercritical CO₂ extracts with time, at different extraction pressures and to emphasize the most favorable condition for the extraction of different terpene hydrocarbon groups, reporting the qualitative differences among extracts collected during successive extraction time periods. Juniper berry extracts were analyzed by capillary gas chromatography, using flame ionization (GC-FID) and mass spectrometric detection (GC-MS). More than 200 constituents were detected in the extracts and the contents of 50 compounds were reported in the work. Dependence of the percentage yields of monoterpene, sesquiterpene, oxygenated monoterpene and oxygenated sesquiterpene hydrocarbon groups on extraction time was investigated and conditions that favored the yielding of each terpene groups were emphasized. GC-MS analysis of FAME, prepared by transesterification of pumpkin seed oil with KOH in methanol, was performed. Fatty acid compositions of supercritical CO₂ pumpkin seed extract fractions collected in successive time intervals over the course of the extraction were determined. The same fractions were analyzed by high pressure liquid chromatography (HPLC), using diode-array detector (DAD) in order to determine a- and g-tocopherol contents. Sterol and squalene contents were determined by GC-MS analysis, as well. Conditions that favored the yielding of tocopherols, squalene and sterols were emphasized. A general mass transfer model and its simlifications were analysed. Extraction curves were evaluated by &ldquo;hot sphere&rdquo; mathematical models SSM-1 (Single Sphere Model 1 &ndash; in which the external mass transfer coefficient also influences the extraction profile and film mass transfer coefficients were estimated by the correlations), SSM-1 (2 par) (film mass transfer coefficient is used as the second adjustable parameter), SSM-2 (only effective diffusivity influence is considered), Characteristic time model and by the extended Lack&rsquo;s plug-flow model given by Sovov&aacute;. A combined model of Hong et al. was also fitted to the experimental data for pumpkin seed oil SCCO_2&nbsp;extractions. Relative merits of the models are demonstrated. Good agreement between the extended Lack&rsquo;s plug-flow model and the experimental measurements was obtained.</p>

Tong Hoi Yee. / "July, 2003." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (p. 237-253). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

O presente trabalho investiga a aplicação do processo de extração com fluido supercrítico (EFS) para a obtenção de compostos fenólicos a partir de Butia capitata, coletado na Região Sul do Brasil. A planta, chamada popularmente de butiá, é uma espécie nativa da Argentina, Uruguai, Paraguai e Brasil. Os frutos do butiá são comestíveis e bastante apreciados pelas populações locais, que os consomem ao natural ou na forma de licores, geléias ou doces. Estudos recentes revelam que compostos fenólicos estão presentes nos frutos do butiá. Estes compostos merecem atenção por apresentarem atividade antioxidante, por prevenirem doenças cardiovasculares e reduzirem o risco de câncer. Atualmente existem diferentes formas para a obtenção de compostos fenólicos presentes em matrizes vegetais, porém muitas delas utilizam solventes orgânicos a altas temperaturas, o que deprecia o valor comercial dos extratos. Neste estudo, é utilizada uma tecnologia limpa, que tem como solvente o dióxido de carbono (CO2) em condições supercríticas. O CO2 é não-tóxico e não-inflamável, o que faz dele uma opção mais segura, quando comparado a outros solventes. Além disso, no estado supercrítico, o CO2 apresenta condições bastante favoráveis para a extração, como altas difusividades e massas específicas elevadas. Uma característica que deve ser ressaltada é a possibilidade de utilizar baixas temperaturas na extração, comparativamente aos processos que utilizam solventes líquidos, uma vez que os compostos fenólicos são termolábeis. Nos experimentos, foi utilizada apenas a polpa desidratada. O planejamento experimental foi elaborado avaliando a influência de três variáveis de processo em três níveis: pressão (150, 200 e 250 bar), temperatura (40, 50 e 60°C) e teor de cossolvente (1, 3 e 5% de etanol). Os extratos obtidos foram analisados em cromatografia líquida de alta eficiência (CLAE), sendo os rendimentos expressos em mg do composto identificado por CLAE /100g de polpa de butiá desidratada (PBD), e pelo método Folin-Ciocalteau com os rendimentos em compostos fenólicos totais (CFT) expressos em mg de rutina equivalente (RE)/100g PBD. Foram identificados cinco compostos majoritários nos extratos nas análises em CLAE. As maiores concentrações foram encontradas nas condições de 250 bar, 60°C e 5% de etanol. Os compostos identificados foram o ácido clorogênico (0,46mg/100g PBD), o ácido ferúlico (1,45mg/100g PBD), a rutina (3,47mg/100g PBD), a quercetina (0,90mg/100g PBD) e o canferol (1,93mg/100g PBD). Em termos de CFT, a melhor condição de extração foi de 200 bar, 50°C e 5% de etanol, resultando em 23,09mg RE/100g PBD. Os extratos também foram avaliados quanto ao poder de redução do radical DPPH•, pelo método IC50. O método fornece a quantidade necessária de extrato pra varrer 50% do radical. Como esperado, o extrato obtido na corrida experimental de maior rendimento em CFT apresentou maior atividade antioxidante (17,4 mg/mL), seguido da corrida experimental de maior rendimento em compostos fenólicos isolados (56,1 mg/mL) e, com menos atividade, o extrato obtido por solvente orgânico (80,0 mg/mL). / In this work it is investigated the application of supercritical fluid extraction to obtain phenolic compounds from Butia capitata, collected in southern Brazil. This plant, known popularly as butiá, is a native species in Argentina, Uruguay, Paraguay and Brazil. The edible fruits are popular and eaten raw or as liqueurs, jellies or jams. In recent studies, it is shown that phenolic compounds are present in the fruits of butiá. These compounds deserve attention because they have antioxidant activity, preventing cardiovascular disease and reducing the risk of cancer. There are different processes to obtain phenolic compounds from plant matrices, but many of them make use of organic solvents at high temperatures, which depreciates the extract value. In this study, it is used a clean technology, with carbon dioxide (CO2) as solvent in supercritical conditions. The CO2 is nontoxic and nonflammable that makes it a safer option than other solvents. Furthermore, in supercritical conditions the CO2 has favorable conditions for extraction, as high diffusivities and densities. A feature that should be emphasized is the possibility of using low temperatures in the extract, when compared to processes using liquid solvents, since the phenolic compounds are decomposed by high temperature. In the experiments only the dried pulp was used. The experimental design was developed to assess the influence of three process variables at three levels: pressure (150, 200 e 250 bar), temperature (40, 50 e 60°C) and cosolvent content (1, 3 e 5% of ethanol). The extracts were analyzed by high performance liquid chromatography (HPLC), in which the yields were expressed in terms of mg of the identified phenolic compounds by HPLC/100g of dried pulp and by the Folin-Ciocalteau method, with yields, as total phenolic compounds, expressed in mg of rutin equivalent/100g of dried pulp. It were identified five majority phenolic compounds by HPLC. Its highest concentrations were found in the conditions of 250 bar, 60°C and 5% of cosolvent. The identified compounds were chlorogenic acid (0,46mg/100g of dried pulp), ferulic acid (1,45mg/100g of dried pulp), rutin (3,47mg/100g of dried pulp), quercetin (0,90mg/100g of dried pulp) and kaempferol (1,93mg/100g of dried pulp). In terms of total phenolic compounds, the best conditions were 200 bar, 50°C and 5% of cosolvent, which resulted in 23,09mg of rutin equivalent/100g of dried pulp. Also, the antioxidant activity of the extracts was measured by scavenging of the DPPH• radical, by the IC50 method. The method provides the necessary amount of extract to scavenging 50% of the radial. As expected, the extract obtained in experimental run with the highest yield in CFT showed a higher antioxidant activity (17.4 mg / mL), followed by the experimental run with the highest yield in phenolic compounds isolated (56.1 mg / mL), and, with less activity, the extract obtained by organic solvent (80.0 mg / mL).

Supercritical fluid extraction has been used to recover biomaterials from natural matrices. Mathematical modeling of the extraction is required for process design and scale up. Existing models in literature are correlative and dependent upon the experimental data. Construction of predictive models giving reliable results in the lack of experimental data is precious. The long term objective of this study was to construct a predictive mass transfer model, representing supercritical fluid extraction of biomaterials in packed beds by the method of volume averaging. In order to develop mass transfer equations in terms of volume averaged variables, velocity and velocity deviation fields, closure variables were solved for a specific case and the coefficients of volume averaged mass transfer equation for the specific case were computed using one and two-dimensional geometries via analytical and numerical solutions, respectively. Spectral Element method with Domain Decomposition technique, Preconditioned Conjugate Gradient algorithm and Uzawa method were used for the numerical solution. The coefficients of convective term with additional terms of volume averaged mass transfer equation were similar to superficial velocity. The coefficients of dispersion term were close to diffusivity of oil in supercritical carbon dioxide. The coefficients of interphase mass transfer term were overestimated in both geometries. Modifications in boundary conditions, change in geometry of particles and use of three-dimensional computations would improve the value of the coefficient of interphase mass transfer term.

Ingestion of extracts prepared from various medicinal plants to induce or augment labour is common amongst Black South African women during the late stages of pregnancy. This applies particularly to the rural areas where modern health care facilities are often lacking. Many of these plants have not been investigated scientifically and one needs to substantiate claims of quality, safety and efficacy. Furthermore, it is believed that the consumption of these plant extracts can result in foetal meconium staining at delivery. An investigation into the uterotonic properties of three plants viz. Ekebergia capensis Sparrm. Clivia miniata (Lindl.) Regel. and Grewia occidentalis L. were carried out using guinea pig uterine smooth muscle in vitro. Supercritical fluid extraction was performed with water modified supercritical carbon dioxide to extract the uterotonic components. An attempt was also made to couple supercritical fluid extraction directly on-line to the bioassay so that on line screening of crude plant extracts could be performed within short periods of time. The effects of supercritical CO2 decompression on temperature and pH of the muscle bathing solution were considered since these factors affect muscle contractility. The direct effects of excess CO2 on intracellular mechanisms were eliminated by constructing a CO2 reduction interface together with passage of carbogen which aided in the rapid displacement of excess CO2, As samples of these extracts were found to induce muscle contraction, supercritical fluid fractionation (SFF) was performed by sequentially increasing the fluid density. Extracted fractions were obtained by sequentially increasing the pressure at constant temperature and modifier concentration in an attempt to identify the active fractions. Extractions were performed at 200 atm, 300 atm and 400 atm respectively. Subsequent testing of these fractions enabled the detection of active and inactive fractions as well as a fraction that had a spasmolytic effect on uterine muscle. The 400 atm extracts of E. capensis and C. miniata displayed maximum activity while only the 300 atm extract of G. occidentalis induced uterine muscle contraction. Subsequent analysis of the sequentially extracted fractions, by high performance liquid chromatography and micellar electrokinetic capillary chromatography revealed that certain compounds present in the fractions that stimulated muscle contraction, were sensitive to the extraction pressure hence making it possible to determine the compounds that were likely to be active. Column chromatography followed by various spectroscopic techniques were performed in an attempt to isolate and elucidate the structures of the compounds that were present in the plant extracts. The extract of Ekebergia capensis yielded five known compounds (B-sitosterol, oleanonic acid, 3-epioleanolic acid, 2,3,22,23-tetrahydroxy-2,6,1 0, 15,19 ,23-hexamethyl-6, 10, 14, 18- tetracosatetrene and 7-hydroxy-6-methoxy coumarin. The extract of Clivia miniata yieded linoleic acid and 5-hydroxymethyl-2-furancarboxaldehyde while the extract of Grewia occidentalis yielded 3-(4-hydroxy-3-methoxyphenyl)-2-propenal, a novel compound 2,2' ,6,6'-tetramethoxy-4'-al-4-(w-oxo-E-propenyl)-biphenyl and oleanonic acid. The pure compounds were further evaluated pharmacologically to identify the active components and assess the physiological mode of action by the use of various receptor blockers. Oleanonic acid, 3-epioleanolic acid, linoleic acid and 5- hydroxymethyl-2-furancarboxaldehyde and 3-(4-hydroxy-3-methoxyphenyl)-2-propenal were found to induce an agonistic muscle response. All these compounds were observed to mediate their effects through the cholinergic receptors. The results obtained in this study supports the claim of these plants possessing uterotonic properties. / Thesis (Ph.D.)-University of Natal, Durban, 1997.

O presente trabalho investiga a aplicação do processo de extração com fluido supercrítico (EFS) para a obtenção de compostos fenólicos a partir de Butia capitata, coletado na Região Sul do Brasil. A planta, chamada popularmente de butiá, é uma espécie nativa da Argentina, Uruguai, Paraguai e Brasil. Os frutos do butiá são comestíveis e bastante apreciados pelas populações locais, que os consomem ao natural ou na forma de licores, geléias ou doces. Estudos recentes revelam que compostos fenólicos estão presentes nos frutos do butiá. Estes compostos merecem atenção por apresentarem atividade antioxidante, por prevenirem doenças cardiovasculares e reduzirem o risco de câncer. Atualmente existem diferentes formas para a obtenção de compostos fenólicos presentes em matrizes vegetais, porém muitas delas utilizam solventes orgânicos a altas temperaturas, o que deprecia o valor comercial dos extratos. Neste estudo, é utilizada uma tecnologia limpa, que tem como solvente o dióxido de carbono (CO2) em condições supercríticas. O CO2 é não-tóxico e não-inflamável, o que faz dele uma opção mais segura, quando comparado a outros solventes. Além disso, no estado supercrítico, o CO2 apresenta condições bastante favoráveis para a extração, como altas difusividades e massas específicas elevadas. Uma característica que deve ser ressaltada é a possibilidade de utilizar baixas temperaturas na extração, comparativamente aos processos que utilizam solventes líquidos, uma vez que os compostos fenólicos são termolábeis. Nos experimentos, foi utilizada apenas a polpa desidratada. O planejamento experimental foi elaborado avaliando a influência de três variáveis de processo em três níveis: pressão (150, 200 e 250 bar), temperatura (40, 50 e 60°C) e teor de cossolvente (1, 3 e 5% de etanol). Os extratos obtidos foram analisados em cromatografia líquida de alta eficiência (CLAE), sendo os rendimentos expressos em mg do composto identificado por CLAE /100g de polpa de butiá desidratada (PBD), e pelo método Folin-Ciocalteau com os rendimentos em compostos fenólicos totais (CFT) expressos em mg de rutina equivalente (RE)/100g PBD. Foram identificados cinco compostos majoritários nos extratos nas análises em CLAE. As maiores concentrações foram encontradas nas condições de 250 bar, 60°C e 5% de etanol. Os compostos identificados foram o ácido clorogênico (0,46mg/100g PBD), o ácido ferúlico (1,45mg/100g PBD), a rutina (3,47mg/100g PBD), a quercetina (0,90mg/100g PBD) e o canferol (1,93mg/100g PBD). Em termos de CFT, a melhor condição de extração foi de 200 bar, 50°C e 5% de etanol, resultando em 23,09mg RE/100g PBD. Os extratos também foram avaliados quanto ao poder de redução do radical DPPH•, pelo método IC50. O método fornece a quantidade necessária de extrato pra varrer 50% do radical. Como esperado, o extrato obtido na corrida experimental de maior rendimento em CFT apresentou maior atividade antioxidante (17,4 mg/mL), seguido da corrida experimental de maior rendimento em compostos fenólicos isolados (56,1 mg/mL) e, com menos atividade, o extrato obtido por solvente orgânico (80,0 mg/mL). / In this work it is investigated the application of supercritical fluid extraction to obtain phenolic compounds from Butia capitata, collected in southern Brazil. This plant, known popularly as butiá, is a native species in Argentina, Uruguay, Paraguay and Brazil. The edible fruits are popular and eaten raw or as liqueurs, jellies or jams. In recent studies, it is shown that phenolic compounds are present in the fruits of butiá. These compounds deserve attention because they have antioxidant activity, preventing cardiovascular disease and reducing the risk of cancer. There are different processes to obtain phenolic compounds from plant matrices, but many of them make use of organic solvents at high temperatures, which depreciates the extract value. In this study, it is used a clean technology, with carbon dioxide (CO2) as solvent in supercritical conditions. The CO2 is nontoxic and nonflammable that makes it a safer option than other solvents. Furthermore, in supercritical conditions the CO2 has favorable conditions for extraction, as high diffusivities and densities. A feature that should be emphasized is the possibility of using low temperatures in the extract, when compared to processes using liquid solvents, since the phenolic compounds are decomposed by high temperature. In the experiments only the dried pulp was used. The experimental design was developed to assess the influence of three process variables at three levels: pressure (150, 200 e 250 bar), temperature (40, 50 e 60°C) and cosolvent content (1, 3 e 5% of ethanol). The extracts were analyzed by high performance liquid chromatography (HPLC), in which the yields were expressed in terms of mg of the identified phenolic compounds by HPLC/100g of dried pulp and by the Folin-Ciocalteau method, with yields, as total phenolic compounds, expressed in mg of rutin equivalent/100g of dried pulp. It were identified five majority phenolic compounds by HPLC. Its highest concentrations were found in the conditions of 250 bar, 60°C and 5% of cosolvent. The identified compounds were chlorogenic acid (0,46mg/100g of dried pulp), ferulic acid (1,45mg/100g of dried pulp), rutin (3,47mg/100g of dried pulp), quercetin (0,90mg/100g of dried pulp) and kaempferol (1,93mg/100g of dried pulp). In terms of total phenolic compounds, the best conditions were 200 bar, 50°C and 5% of cosolvent, which resulted in 23,09mg of rutin equivalent/100g of dried pulp. Also, the antioxidant activity of the extracts was measured by scavenging of the DPPH• radical, by the IC50 method. The method provides the necessary amount of extract to scavenging 50% of the radial. As expected, the extract obtained in experimental run with the highest yield in CFT showed a higher antioxidant activity (17.4 mg / mL), followed by the experimental run with the highest yield in phenolic compounds isolated (56.1 mg / mL), and, with less activity, the extract obtained by organic solvent (80.0 mg / mL).

O presente trabalho investiga a aplicação do processo de extração com fluido supercrítico (EFS) para a obtenção de compostos fenólicos a partir de Butia capitata, coletado na Região Sul do Brasil. A planta, chamada popularmente de butiá, é uma espécie nativa da Argentina, Uruguai, Paraguai e Brasil. Os frutos do butiá são comestíveis e bastante apreciados pelas populações locais, que os consomem ao natural ou na forma de licores, geléias ou doces. Estudos recentes revelam que compostos fenólicos estão presentes nos frutos do butiá. Estes compostos merecem atenção por apresentarem atividade antioxidante, por prevenirem doenças cardiovasculares e reduzirem o risco de câncer. Atualmente existem diferentes formas para a obtenção de compostos fenólicos presentes em matrizes vegetais, porém muitas delas utilizam solventes orgânicos a altas temperaturas, o que deprecia o valor comercial dos extratos. Neste estudo, é utilizada uma tecnologia limpa, que tem como solvente o dióxido de carbono (CO2) em condições supercríticas. O CO2 é não-tóxico e não-inflamável, o que faz dele uma opção mais segura, quando comparado a outros solventes. Além disso, no estado supercrítico, o CO2 apresenta condições bastante favoráveis para a extração, como altas difusividades e massas específicas elevadas. Uma característica que deve ser ressaltada é a possibilidade de utilizar baixas temperaturas na extração, comparativamente aos processos que utilizam solventes líquidos, uma vez que os compostos fenólicos são termolábeis. Nos experimentos, foi utilizada apenas a polpa desidratada. O planejamento experimental foi elaborado avaliando a influência de três variáveis de processo em três níveis: pressão (150, 200 e 250 bar), temperatura (40, 50 e 60°C) e teor de cossolvente (1, 3 e 5% de etanol). Os extratos obtidos foram analisados em cromatografia líquida de alta eficiência (CLAE), sendo os rendimentos expressos em mg do composto identificado por CLAE /100g de polpa de butiá desidratada (PBD), e pelo método Folin-Ciocalteau com os rendimentos em compostos fenólicos totais (CFT) expressos em mg de rutina equivalente (RE)/100g PBD. Foram identificados cinco compostos majoritários nos extratos nas análises em CLAE. As maiores concentrações foram encontradas nas condições de 250 bar, 60°C e 5% de etanol. Os compostos identificados foram o ácido clorogênico (0,46mg/100g PBD), o ácido ferúlico (1,45mg/100g PBD), a rutina (3,47mg/100g PBD), a quercetina (0,90mg/100g PBD) e o canferol (1,93mg/100g PBD). Em termos de CFT, a melhor condição de extração foi de 200 bar, 50°C e 5% de etanol, resultando em 23,09mg RE/100g PBD. Os extratos também foram avaliados quanto ao poder de redução do radical DPPH•, pelo método IC50. O método fornece a quantidade necessária de extrato pra varrer 50% do radical. Como esperado, o extrato obtido na corrida experimental de maior rendimento em CFT apresentou maior atividade antioxidante (17,4 mg/mL), seguido da corrida experimental de maior rendimento em compostos fenólicos isolados (56,1 mg/mL) e, com menos atividade, o extrato obtido por solvente orgânico (80,0 mg/mL). / In this work it is investigated the application of supercritical fluid extraction to obtain phenolic compounds from Butia capitata, collected in southern Brazil. This plant, known popularly as butiá, is a native species in Argentina, Uruguay, Paraguay and Brazil. The edible fruits are popular and eaten raw or as liqueurs, jellies or jams. In recent studies, it is shown that phenolic compounds are present in the fruits of butiá. These compounds deserve attention because they have antioxidant activity, preventing cardiovascular disease and reducing the risk of cancer. There are different processes to obtain phenolic compounds from plant matrices, but many of them make use of organic solvents at high temperatures, which depreciates the extract value. In this study, it is used a clean technology, with carbon dioxide (CO2) as solvent in supercritical conditions. The CO2 is nontoxic and nonflammable that makes it a safer option than other solvents. Furthermore, in supercritical conditions the CO2 has favorable conditions for extraction, as high diffusivities and densities. A feature that should be emphasized is the possibility of using low temperatures in the extract, when compared to processes using liquid solvents, since the phenolic compounds are decomposed by high temperature. In the experiments only the dried pulp was used. The experimental design was developed to assess the influence of three process variables at three levels: pressure (150, 200 e 250 bar), temperature (40, 50 e 60°C) and cosolvent content (1, 3 e 5% of ethanol). The extracts were analyzed by high performance liquid chromatography (HPLC), in which the yields were expressed in terms of mg of the identified phenolic compounds by HPLC/100g of dried pulp and by the Folin-Ciocalteau method, with yields, as total phenolic compounds, expressed in mg of rutin equivalent/100g of dried pulp. It were identified five majority phenolic compounds by HPLC. Its highest concentrations were found in the conditions of 250 bar, 60°C and 5% of cosolvent. The identified compounds were chlorogenic acid (0,46mg/100g of dried pulp), ferulic acid (1,45mg/100g of dried pulp), rutin (3,47mg/100g of dried pulp), quercetin (0,90mg/100g of dried pulp) and kaempferol (1,93mg/100g of dried pulp). In terms of total phenolic compounds, the best conditions were 200 bar, 50°C and 5% of cosolvent, which resulted in 23,09mg of rutin equivalent/100g of dried pulp. Also, the antioxidant activity of the extracts was measured by scavenging of the DPPH• radical, by the IC50 method. The method provides the necessary amount of extract to scavenging 50% of the radial. As expected, the extract obtained in experimental run with the highest yield in CFT showed a higher antioxidant activity (17.4 mg / mL), followed by the experimental run with the highest yield in phenolic compounds isolated (56.1 mg / mL), and, with less activity, the extract obtained by organic solvent (80.0 mg / mL).