Ce travail de recherche porte sur l’intensification de l’extraction des polyphénols à partir des écorces de chêne pédonculé et d’épicéa commun par des technologies innovantes : les champs électriques pulsés (CEP), les ultrasons (US) et les micro-ondes (MO). Ces prétraitements permettent l’amélioration de l’extraction par endommagement des membranes et/ou parois cellulaires. L’effet de chacune de ces techniques (CEP, US et MO) sur l’extraction des polyphénols a été mis en évidence à travers une étude d’optimisation quantitative et qualitative : suivi du rendement des polyphénols, de l’activité antioxydante et caractérisation chimiques des composés extraits.Une étude comparative des prétraitements (CEP, US et MO) couplés à une diffusion en milieu hydro-alcoolique alcalin, a permis de mieux comprendre les mécanismes mis en jeu lors d’un traitement d’un tissu fibreux. L’étude a prouvé que l’efficacité du procédé est indépendante de la famille d’arbre à laquelle appartiennent les écorces (résineux ou feuillus). De plus, pour valoriser les écorces de bois, l’application d’un prétraitement par CEP (20 kV/cm, 200 impulsions, 3,2 kJ/g bois) suivi d’une diffusion semble être une alternative aux ultrasons, micro-ondes et à l’extraction avec des écorces préalablement broyées. En effet, grâce à l’action électrique et mécanique des CEP, ce prétraitement permet d’obtenir un extrait riche en polyphénols (10,5 g EAG/100g MS pour l’épicéa soit 83 % d’efficacité et 5 g EAG/100g MS pour le chêne soit 82 % d’efficacité). / This research work focuses on the intensification of polyphenols extraction from Quercus robur and Norway spruce barks using innovative technologies : pulsed electric field (PEF), ultrasound assisted extraction (UAE) and microwave assisted extraction (MAE). These pre-treatments enhance the release of intracellular compounds by damaging the membrane and/or cell wall. The effect of each of these technologies (PEF, UAE and MAE) on polyphenols extraction has been highlighted in a quantitative and qualitative optimization analysis by evaluating the polyphenols concentration, antioxidant activity and by the chemical characterization of the extracted compounds.A comparative study of pre-treatments (PEF, UAE and MAE) coupled with an extraction step in an alkaline hydro-alcoholic medium allowed us to better understand the involved phenomena. The induced process efficiency is independent of the tree family to which the bark belongs (coniferous and hardwood). For bark valorization, the application of PEF treatment (20 kV/cm, 200 pulses, 3.2 kJ/g bark) followed by a diffusion step seems to be an alternative to ultrasound and microwave assisted extractions and to the extraction from grinded barks. In fact, the electrical and mechanical effect of PEF treatment allow to obtain an extract rich in polyphenols (10.5 g GAE/100g DM and an efficiency of 83 % for Norway spruce and 5 g GAE /100g DM and an efficiency of 82 % for Quercus robur bark).

<p>U okviru ove disertacije ispitane su mogućnosti primene savremenih metoda za dobijanje tečnih ekstrakata (ultrazvučna ekstrakcija, mikrotalasna ekstrakcija i ekstrakcija subkritičnom vodom) i lipofilnih ekstrakata (ekstrakcija superkritičnim ugljendioksidom) bogatih polifenolima iz nadzemnog dela očajnice (Marrubium vulgare L.). Tečni ekstrakti su optimizovani primenom eksperimentalnog dizajna i metode odzivne povr&scaron;ine, i podvrgnuti su spray drying tehnici su&scaron;enja. Tečni i suvi ekstrakti su detaljno ispitani po pitanju hemijskog sastava i biolo&scaron;ke aktivnosti, antimikrobne i in vitro antihiperglikemijske aktivnosti.<br />Za svaku od navedenih ekstrakcionih tehnika ispitan je uticaj glavnih parametara: ultrazvučna ekstrakcija (temperatura, vreme ekstrakcije i snaga ultrazvuka), mikrotalasna ekstrakcija (koncentracija etanola, vreme ekstrakcije i snaga mikrotalasa) i ekstrakcija subkritičnom vodom (temperatura, vreme ekstrakcije i koncentracija HCl u ekstragensu). Kod tečnih ekstrakata dobijenih ultrazvučnom i mikrotalasnom ekstrakcijom na optimizovanim uslovima utvrđeno je prisustvo hlorogenske kiseline i kvercetina koji nisu detektovani u maceratima. Ispitana je antimikrobna aktivnost oba ekstrakta i utvrđeno da je B. cereus najosetljiviji bakterijski soj, dok je u slučaju kvasaca S. cerevisiae posebno osetljiv na oba ekstrakta. Pored ove aktivnosti ispitana je i in vitro antihiperglikemijska aktivnost oba ekstrakta prema &alpha;-amilazi i &alpha;-glukozidazi, pri čemu ultrazvučni ekstrakt pokazuje veću antihiperglikemijsku aktivnost (50,63% inhibira &alpha;-amilazu i 48,67% inhibira &alpha;-glukozidazu) &scaron;to se potencijalno može objasniti prisustvom hlorogenske kiseline (33,11 &mu;g/mL) i kvercetina (34,88 &mu;g/mL). U subkritičnom ekstraktu, dobijenom na optimalnim uslovima, detektovano je jedino prisustvo hidroksi metilfurfurala usled čega ovaj ekstrakt nije podvrgnut ispitivanju antimikrobne i antihiperglikemijske aktivnosti.<br />U cilju ekstrakcije lipofilnih komponenata M. vulgare primenjene su destilacija etarskog ulja (0,05%), Soxhlet ekstrakcija (3,23%) i ekstrakcija superkritičnim ugljendioksidom na pritiscima 100, 200 i 300 bar i temperaturama 40, 50 i 60 &deg;C. Najdominantnija komponenta u svim dobijenim superkritičnim ekstraktima je hemotaksonomski marker marubiin koji nije identifikovan u Soxhlet ekstraktu.<br />Tečni ekstrakti dobijeni ultrazvučnom i mikrotalasnom ekstrakcijom na optimizovanim uslovima i macerat su osu&scaron;eni spray drying tehnikom (uz dodatak 10 i 50% maltodekstrina) u cilju dobijanja stabilnije forme suvog ekstrakta. Suvim ekstraktima su određene najznačajnije fizičke osobine i hemijski sastav kao i antimikrobna i antihiperglikemijska aktivnost kako bi se procenila mogućnost njihove inkorporacije u funkcionalnu hranu, dijetetske suplemente ili u formulaciji različitih gotovih proizvoda koji se primenjuju preventivno ili radi pobolj&scaron;anja zdravlja ljudi.</p> / <p>Within the scope of this dissertation, the possibilities of applying modern methods for obtaining liquid (ultrasonic extraction, microwave extraction and subcritical water extraction) and lipophilic extracts (extraction with supercritical carbon dioxide) rich in polyphenols from the aboveground part of white horehound (Marrubium vulgare L.) were examined. Liquid extracts were optimized using an experimental design and response surface method, and subjected to spray drying. Liquid and dry extracts have been extensively examined for their chemical composition and biological activity, antimicrobial and in vitro antihyperglycaemic activities.<br />For each of these extraction techniques, the influence of the main parameters was examined: ultrasonic extraction (temperature, extraction time and ultrasound power), microwave extraction (ethanol concentration, extraction time and microwave power) and subcritical water extraction (temperature, extraction time and HCl concentration in the extractant). Liquid extracts obtained by ultrasonic and microwave extraction under optimized conditions revealed the presence of chlorogenic acid and quercetin, which were not detected in macerates. The antimicrobial activity of both extracts was examined and B. cereus was found to be the most sensitive bacterial strain, whereas in the case of yeast S. cerevisiae was particularly sensitive to both extracts. In addition to this activity, the in vitro antihyperglycaemic activities of both extracts against &alpha;-amylase and &alpha;-glucosidase were investigated, with ultrasound extract showing higher antihyperglycemic activity (50.63% inhibited &alpha;-amylase and 48.67% inhibited &alpha;-glucosidase) which could potentially be explained by the presence of chlorogenic acid (33.11 &mu;g/mL) and quercetin (34.88 &mu;g/mL). In the subcritical extract, obtained under optimal conditions, only the presence of hydroxy methylfurfural was detected, and this extract was not subjected to antimicrobial and antihyperglycemic activity.<br />For the extraction of lipophilic components of M. vulgare, distillation of essential oil (0.05%), Soxhlet extraction (3.23%) and extraction with supercritical carbon dioxide at pressures of 100, 200 and 300 bar and at temperatures of 40, 50 and 60 &deg; C were applied. The most dominant component in all the supercritical extracts obtained is the chemotaxonomic marker marubiin, which was not identified in the Soxhlet extract.<br />The liquid extracts obtained by the ultrasound and microwave extraction under optimized conditions and the macerate were spray dried (with the addition of 10 and 50% maltodextrin) to obtain a more stable form of the dry extract. Dry extracts underwent determination of the most important physical properties and chemical composition as well as antimicrobial and antihyperglycemic activities to evaluate their incorporation into functional foods, dietary supplements or in the formulation of various finished dosage forms that are administered preventively or to improve human health.</p>

<br /> Vários compostos químicos são usados para o controle de pragas e doenças na agricultura com a finalidade de aumentar a produtividade. É de conhecimento científico que tais compostos afetam negativamente a saúde humana e animal por meio da contaminação dos alimentos e do meio ambiente. Assim, o uso de substâncias obtidas da própria natureza para o combate de pragas e plantas invasoras é uma alternativa para o controle e, consequente, prevenção da contaminação ambiental. Neste trabalho foram avaliados os extratos aquosos das folhas da leguminosa feijão-de-porco (Canavalia ensiformis) como bioerbicida pós-emergente aplicado no controle de plantas invasoras em cultura de soja e seus efeitos no solo. Salienta-se que não há informações sobre os efeitos desses bioerbicida no solo. Os compostos fenólicos, em especial os ácidos fenólicos, têm ação inibitória no crescimento de plantas invasoras. O processo de extração dos compostos fenólicos foi feito em um sistema de digestão por micro-ondas, com aproximadamente 2 g de material vegetal seco, seguida de injeção cromatográfica. Para otimização do procedimento de extração via micro-ondas os parâmetros avaliados foram: tempo de irradiação, temperatura e rampa aplicada. Foram realizadas determinações cromatográficas para identificação e quantificação dos compostos fenólicos: rutina, ácido clorogênico, ácido ferúlico e naringenina presentes nas folhas do feijão-de-porco por HPLC-UV, mediante metodologia de extração por micro-ondas. Todo o trabalho foi desenvolvido de acordo com os requisitos de gestão da qualidade referentes às normas NBR ISO/IEC 17025 e BPL. / <br /> Several chemical compounds are used for pest and disease control in agriculture in order to increase productivity. It is well know that such pesticides adversely affect human and animal health through contamination by food and environment. Thus, the use of substances obtained from nature itself to combat pests and weeds is an alternative for the control of those and, consequently, prevent environmental contamination. This work were assessed aqueous extracts of jack bean leaves (Canavalia ensiformis) as a post-emergent bioherbicide applied in weed control in soybean crops and its effects on the soil. It is noteworthy there is not information on the effects of these bioherbicides on the soil. Phenolics compounds, notably, phenolics acids, have inhibitory action on the growth of weeds. The process of extraction of phenolic compounds was carried out in a digestion system by microwave, using approximately 2 g dry plant material, followed by chromatographic injection. For optimization of the extraction procedure by microwave-assisted extraction the factors evaluated were irradiation time, temperature and ramp time. Chromatographic determinations were performed for identification and quantification of the phenolic compounds: rutin, chlorogenic acid, ferulic acid and naringenin present in the Canavalia ensiformis leaves by HPLC-UV, through microwave extraction methodology. All the study was developed in compliance with the quality management concepts covered in NBR ISO/IEC 17025 and GLP.

Cette étude a deux objectifs principaux : l’extraction de tanins condensés d’écorces de pin maritime et la formulation de colles tanin-lignosulfonate. Deux méthodes d’extraction ont été étudiées. La première est une extraction à l’eau chaude ; c’est une technique simple, peu coûteuse, sans solvant. La deuxième est une extraction assistée par micro-ondes ; c’est une technique innovante, rapide et peu consommatrice en solvant. L’optimisation des conditions d’extraction à l’eau chaude a été réalisée. Les extraits ont été caractérisés par des dosages colorimétriques, leur réactivité au formaldéhyde, par infrarouge à transformée de Fourier (IRTF), par chromatographie en phase liquide à haute pression, par 1H RMN et 2D HSQC RMN. L’impact de la granulométrie sur l’extraction de polyphénols et particulièrement de tanins condensés par extraction assistée par micro-ondes a été étudié pour la première fois. Les deux types d’extraction ont été comparés. L’extraction assistée par micro-ondes a un rendement en extractibles inférieur à l’extraction à l’eau chaude. Mais elle extrait plus de tanins condensés, de flavonoïdes simples et plus de sucres. Quelle que soit la méthode d’extraction, les tanins condensés majoriatires extraits de l’écorce de pin maritime sont de la catéchine, de l’épicatéchine, de l’épicatéchine gallate et de l’épigallocatéchine. Des colles tanin-lignosulfonate ont été produites en utilisant l’héxaméthylènetetramine comme durcisseur. Dans un premier temps, des tanins de mimosa ont été utilisés avec des lignosulfonates de sodium et des lignosulfonates d’ammonium. Les lignosulfonates ont subi deux traitements au glyoxal qui ont été comparés par analyse thermogravimétrique (ATG), par calorimétrie différentielle à balayage (DSC), par les propriétés thermiques et mécaniques de colles et de panneaux de particules avec des lignosulfonates ayant subi les deux traitements ont également été étudiées. L’optimisation du ratio tanin de mimosa-lignosulfonate glyoxalé a été menée et les propriétés thermiques des colles mesurées. L’optimisation des conditions de pressage de panneaux de particules a été réalisée. Des panneaux de particules avec de bonnes performances mécaniques ont été fabriqués. Des colles à base de tanins d’écorce de pin maritime et de lignosulfonates ont été réalisées avec 40% de tanins et 60% de lignosulfonates. Ces colles ont été caractérisées par IRTF, analyse thermomécanique, ATG et DSC. Ces colles sont rentrées dans la fabrication de panneaux de particules. Les émissions de formaldéhyde et la cohésion interne des panneaux ont été mesurées et comparées à des panneaux encollés avec une colle tanin de mimosa-lignosulfonate et une résine urée-formaldéhyde. Grâce à ces résultats, il a été possible de montrer que les panneaux de particules fabriqués à partir de colles bio-sourcées n’émettaient pas de formaldéhyde. / This study has two main objectives: the extraction of condensed tannins from maritime pine bark and the preparation of tannin-lignosulfonate adhesives. Two extraction methods were studied. The first is hot water extraction which is a simple, cheap method without the use of an organic solvent. The second is microwave-assisted extraction which is a fast, innovative method using only a small amount of solvent. Optimum extraction conditions were determined for hot water extraction. The extracts were characterised by their reaction to formaldehyde and by using colorimetric tests, Fourier Transformed Infrared spectroscopy (FTIR), high pressure liquid chromatography, 1H NMR and heteronuclear single quantum correlation 2D NMR.. The two types of extraction were compared. It was found that microwave-assisted extraction produced a lower yield of extractibles than the hot water method but that it produced more condensed tannins, simple flavonoids and sugars. The condensed tannins extracted from maritime pine bark are catechin, epicatechin, epicatechin gallate and epigallocatechin, whatever the extraction method used. Tannin-lignosulfonate adhesives were produced using hexamethylenetetramine as a hardener. First, mimosa tannins were used with sodium lignosulfonates and ammonium lignosulfonates. The lignosulfonates underwent two glyoxal treatments which were compared using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and by determining the thermal and mechanical properties of the adhesives and of the particle boards made using the lignosulfonates resulting from the two treatments. The optimum mimosa tannin-glyoxalated lignosulfonate ratio was determined and the thermal properties of the adhesives were measured. The optimum conditions of pressing the particle boards were determined. Particle boards which recorded a good mechanical performance were produced. Adhesives using maritime pine bark tannins and lignosulfonates were prepared with 40% tannins and 60% lignosulfonates. These adhesives were characterised using FTIR, thermomechanical analysis, TGA and DSC. These adhesives were used to produce particle boards. The emission of formaldehyde and the internal bond of the boards were measured and compared to those of boards made with a mimosa tannin-lignosulfonate adhesive and to those of boards made with a urea-formaldehyde resin. Thanks to these results, we were able to produce particleboards with bio-based adhesives that didn’t emit formaldehyde.

<p style="text-align: justify;">U okviru ove doktorske disertacije ispitana je mogućnost ekstrakcije bioaktivnih jedinjenja iz biljne pra&scaron;ine A. uva-ursi, koja nastaje kao sporedni proizvod u fabrici filter čaja. Za ekstrakciju bioaktivnih jedinjenja primenjene su različite tehnike ekstrakcije (klasična ekstrakcija, ultrazvučna ekstrakcija i ekstrakcija subkritičnom vodom), kao i različiti ekstragensi: voda na sobnoj temperaturi, 30-70% etanol i subkritična voda. Sadržaj bioaktivnih jedinjenja u ekstraktima ispitan je primenom odgovarajućih spektrofotometrijskih metoda i HPLC metode. U ekstrakciji biljne pra&scaron;ine A. uva-ursi detaljno je matematički analiziran uticaj procesnih parametara na ekstrakciju subkritičnom vodom bioaktivnih jedinjenja iz materijala ovog tipa i u tom smislu je posmatran uticaj temperature, vremena i dodatka kiseline, a takođe su određeni uslovi pri kojima je, primenom ove tehnike, moguće ostvariti maksimalnu ekstrakciju bioaktivnih jedinjenja od značaja. Pored toga prikazana je i mogućnost primene spray drying tehnike za su&scaron;enje tečnih i proizvodnju suvih ekstrakta A. uva-ursi u formi praha. Na kraju, na osnovu koncentracije bioaktivnih jedinjenja i njihovog delovanja, dat je predlog nekoliko novih preparata na bazi ekstrakata A. uva-ursi, u tečnoj i čvrstoj formi.</p> / <p>This dissertation investigated the possibility to extract bioactive compounds from A. uva-ursi herbal dust, which occurs as a by-product at the filter-tea<br />factory. Various extraction techniques (classical extraction, ultrasound assisted extraction and subcritical water extraction), were applied for the extraction of bioactive compounds, as well as different solvents: water at room temperature, 30-70% ethanol and subcritical water. The content of bioactive compounds in the extracts was investigated using appropriate spectrophotometric methods and the HPLC method. In the extraction of A. uva-ursi herbal dust a detailed mathematical analysis of the influence of process parameters on subcritical water extraction of bioactive compounds from this type of material was conducted. In this regard the influence of temperature, time and acid addition was observed and the conditions under which it is possible to achieve maximum extraction of significant bioactive compounds, by applying this technique, were determined. In addition, the possibility of applying the spray drying technique for drying the liquid and producing dry A. uva-ursi extracts in the form of powder is also presented. Eventually, based on the concentration of the bioactive compounds and their activity, a proposal for a several new preparations in liquid and solid form, based on A. uva-ursi extracts is given.</p>

<br /> Vários compostos químicos são usados para o controle de pragas e doenças na agricultura com a finalidade de aumentar a produtividade. É de conhecimento científico que tais compostos afetam negativamente a saúde humana e animal por meio da contaminação dos alimentos e do meio ambiente. Assim, o uso de substâncias obtidas da própria natureza para o combate de pragas e plantas invasoras é uma alternativa para o controle e, consequente, prevenção da contaminação ambiental. Neste trabalho foram avaliados os extratos aquosos das folhas da leguminosa feijão-de-porco (Canavalia ensiformis) como bioerbicida pós-emergente aplicado no controle de plantas invasoras em cultura de soja e seus efeitos no solo. Salienta-se que não há informações sobre os efeitos desses bioerbicida no solo. Os compostos fenólicos, em especial os ácidos fenólicos, têm ação inibitória no crescimento de plantas invasoras. O processo de extração dos compostos fenólicos foi feito em um sistema de digestão por micro-ondas, com aproximadamente 2 g de material vegetal seco, seguida de injeção cromatográfica. Para otimização do procedimento de extração via micro-ondas os parâmetros avaliados foram: tempo de irradiação, temperatura e rampa aplicada. Foram realizadas determinações cromatográficas para identificação e quantificação dos compostos fenólicos: rutina, ácido clorogênico, ácido ferúlico e naringenina presentes nas folhas do feijão-de-porco por HPLC-UV, mediante metodologia de extração por micro-ondas. Todo o trabalho foi desenvolvido de acordo com os requisitos de gestão da qualidade referentes às normas NBR ISO/IEC 17025 e BPL. / <br /> Several chemical compounds are used for pest and disease control in agriculture in order to increase productivity. It is well know that such pesticides adversely affect human and animal health through contamination by food and environment. Thus, the use of substances obtained from nature itself to combat pests and weeds is an alternative for the control of those and, consequently, prevent environmental contamination. This work were assessed aqueous extracts of jack bean leaves (Canavalia ensiformis) as a post-emergent bioherbicide applied in weed control in soybean crops and its effects on the soil. It is noteworthy there is not information on the effects of these bioherbicides on the soil. Phenolics compounds, notably, phenolics acids, have inhibitory action on the growth of weeds. The process of extraction of phenolic compounds was carried out in a digestion system by microwave, using approximately 2 g dry plant material, followed by chromatographic injection. For optimization of the extraction procedure by microwave-assisted extraction the factors evaluated were irradiation time, temperature and ramp time. Chromatographic determinations were performed for identification and quantification of the phenolic compounds: rutin, chlorogenic acid, ferulic acid and naringenin present in the Canavalia ensiformis leaves by HPLC-UV, through microwave extraction methodology. All the study was developed in compliance with the quality management concepts covered in NBR ISO/IEC 17025 and GLP.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The main objective of this work was to evaluate the antioxidant and antibacterial activities of extracts of Brassica oleracea var. capitata, obtained by supercritical CO2 and ultrasound-assisted extractions, as well as to carry out the characterization of these extracts using gas chromatography coupled with mass detector. For supercritical CO2, five extractions were performed to investigate the influence of pressure (10-25 MPa) and temperature (20-60°C) on the extraction yield, chemical composition and antioxidant activity towards peroxyl, superoxide and hydroxyl radicals. The highest extraction yield was 0.47% at 60 °C and 25 MPa. In the characterization of the extracts was possible to identify compounds like sulforaphane and iberin nitrile. All extracts showed antioxidant activity for the three radicals, although the highest activity for all radicals was obtained using the extract obtained at 60 °C and 25 MPa (run 2). For the ultrasound-assisted extraction were evaluated the effects of solvent concentration and temperature. The extracts obtained in the optimized extraction condition, were subjected to different hydrolysis conditions before use in biological assays. It was evaluated the antioxidant activity against DPPH, superoxide and peroxyl radicals, besides the antibacterial activity against S. aureus and E. coli. Both crude and hydrolyzed extracts were characterized by gas chromatography coupled with mass detector. The best condition for extraction was 30 ° C and 60% (w /v) of ethanol. All extracts showed antioxidant activity towards DPPH, superoxide and peroxyl radicals, but the use of hydrolyzed extracts improved considerably the antioxidant activities. Antibacterial activity was detected only in extracts hydrolysates Brassica oleracea var. capitata. The main contributions of this work were that the use of supercritical CO2 extraction to obtain bioactive compounds from Brassica oleracea var. capitata showed a promising alternative to conventional methods of extraction, since it allowed the extraction of compounds of interest in science and industry. Besides, in this work was demonstrated that the hydrolysis of extracts can increase the antioxidant activity of plant extracts. / O objetivo principal deste trabalho foi avaliar a atividade antioxidante e antibacteriana de extratos de Brassica oleracea var. capitata, obtidos a partir de extração supercrítica e extração por ultrassom, além de caracterizá-los por cromatografia gasosa acoplada à detector de massas. Para os compostos bioativos apolares de Brassica oleracea var. capitata, utilizou-se extração com CO2 supercrítico e avaliou-se o potencial antioxidante dos extratos. Foram realizadas cinco extrações para investigar a influência da pressão (10 - 25 MPa) e temperatura (20 - 60°C) no rendimento da extração, na composição química e na atividade antioxidante frente os radicais peroxila, superóxido e hidroxila. Obteve-se o maior rendimento de extração 0,47% a 60 °C e 25 MPa. Na caracterização dos extratos foi possível a identificação de compostos como sulforafano e iberin nitrila. Todos os extratos apresentaram atividade antioxidante para os três radicais, porém a maior atividade para todos os radicais foi o extrato obtido a 60°C e 25 MPa. Para os compostos bioativos polares, otimizou-se a extração assistida por ultrassom. Os extratos obtidos nas melhores condições de extração foram submetidos a diferentes condições de hidrólise, antes da sua utilização nos ensaios biológicos. Avaliou-se a atividade antioxidante, frente ao radical DPPH, superóxido e peroxila, além da atividade antibacteriana, frente a S.aureus e E.coli. Tanto os extratos brutos quanto os hidrolisados, foram caracterizados por cromatografia gasosa acoplada à detector de massas. A melhor condição de extração foi a 30ºC e 60% (m/v) de etanol. Todos os extratos apresentaram atividade antioxidante frente aos radicais DPPH, superóxido e peroxila, mas o uso de extratos hidrolisados melhorou consideravelmente a atividade antioxidante. Em relação à atividade antibacteriana, apenas uma amostra, que foi submetida à condição de hidrólise alcalina apresentou ação frente a E.coli. Uma das principais contribuições deste trabalho foi que a utilização de extração com CO2 supercrítico, para obtenção de compostos bioativos de Brassica oleracea var. capitata, mostrou ser uma alternativa promissora em relação aos métodos convencionais de extração, pois permitiu a extração de compostos com interesse científico e industrial. Além disso, foi demonstrado que a hidrólise dos extratos pode aumentar consideravelmente a atividade antioxidante de extratos vegetais em relação aos extratos brutos.

Submitted by Marilene Donadel (marilene.donadel@unioeste.br) on 2018-04-27T00:49:59Z No. of bitstreams: 1 Katia_A_Santos_2018.pdf: 1940481 bytes, checksum: dd10357b3e5c25bdf7e64bb4148af513 (MD5) / Made available in DSpace on 2018-04-27T00:49:59Z (GMT). No. of bitstreams: 1 Katia_A_Santos_2018.pdf: 1940481 bytes, checksum: dd10357b3e5c25bdf7e64bb4148af513 (MD5) Previous issue date: 2018-03-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Candeia (Eremanthus erythropappus) is a native species of the Brazilian Atlantic forest from which an essential oil with high concentration of sesquiterpene α-bisabolol is extracted. α-Bisabolol is an active principle of important application in the cosmetic and pharmaceutical industries due to its anti-inflammatory, antispasmodic, sedative, antiallergic, anti-irritant, cicatrizant and vermifugal properties. Steam distillation is the most common method used to obtain this oil, with requires long periods of time extraction besides the degradation of thermosensitive compounds. Within this context, the aim of this study was to evaluate the quality of the candeia wood oils obtained by non-conventional methods of extraction (supercritical technology by using carbon dioxide and cosolvents, pressurized liquid and ultrasound-assisted extraction), in terms of oil yield, bisabolol content and antioxidant activity. In addition, the oil re-extraction from the industrial residue was also evaluated. The extractions were carried out with CO2 at temperatures of 40, 55 and 70 oC and pressures of 160, 200 and 240 bar, with a solvent mass flow rate of 1.96 x 10−3 kg min−1 and 120 min of total extraction. The highest extraction yield obtained was 1.42 wt% for the candeia wood and 0.41 wt% for the residue, both at 70 oC and 240 bar, and this condition was selected to perform the extractions using cosolvents. Ethanol and ethyl acetate were added to supercritical CO2 at concentrations of 1, 3 and 5 % (v/v), obtaining up to 2.35 wt% of yield. The Soxhlet (360 min) and pressurized liquid (40, 55 and 70 oC; 100 bar and 20 min) extractions showed the affinity of the candeia compounds for polar solvents and the positive effect of the temperature on the yield, which varied from 0.53 to 7.23 wt%. A Box-Benhken design was employed to evaluate the effect of the variables temperature (40, 50 and 60 oC), n-hexane volume to wood mass (10, 15 and 20 mL g-1) and nominal power (150, 300 and 450 W) on the yield of ultrasound-assisted extractions, obtaining in 7 minutes of extraction, up to 83% of the yield obtained in the conventional technique in Soxhlet (1.57 wt%), with a solvent volume 2.5 times smaller. The major compounds identified in the candeia oil were the sesquiterpenes α-bisabolol, eremanthin and costunolide, and the α-bisabolol content in the oil is favored by the lowest CO2 density, with 74.45 % being obtained for the candeia wood and 50.62 % for the residue, in both cases in oil extracted at 70 oC and 160 bar. The addition of ethanol and ethyl acetate cosolvents to CO2 increased the α-bisabolol yield by 41 %. Also, the cosolvents increased the amount of total phenolic content in the oil, and consequently, its antioxidant capacity. The oil fractionation by column chromatography was efficient for α-bisabolol isolation. However, unlike the candeia wood oil, this compound was not effective in inhibiting the Staphylococcus aureus growth. In relation to the supercritical extractions, the Sovová mathematical model presented a good adjustment to the experimental data for all the conditions used. / A candeia (Eremanthus erythropappus) é uma árvore nativa da Mata Atlântica da qual se extrai um óleo essencial com elevada concentração do sesquiterpeno α-bisabolol, princípio ativo de grande aplicação nas indústrias de cosméticos e farmacêutica devido às suas propriedades anti-inflamatória, antiespasmódica, sedativa, antialérgica, anti-irritante, cicatrizante e vermífuga. A obtenção deste óleo em escala industrial é realizada pelo processo de destilação por arraste a vapor, com elevado tempo de extração, além da degradação de compostos termossensíveis. Neste contexto, o presente trabalho tem como objetivo avaliar a qualidade dos óleos da madeira de candeia, obtidos por métodos não convencionais de extração (tecnologia supercrítica com dióxido de carbono e cossolventes, líquidos pressurizados e solvente assistido por ultrassom), em termos de rendimento, teor de α-bisabolol e atividade antioxidante. Ainda, avaliar a re-extração do óleo do resíduo industrial. As extrações foram realizadas com CO2 nas temperaturas de 40, 55 e 70 oC e pressões de 160, 200 e 240 bar, com vazão mássica de solvente de 1,96 x 10-3 kg min-1 e tempo total de 120 minutos. O maior rendimento obtido para o óleo da candeia nas extrações supercríticas foi de 1,42 % e de 0,41 % para o resíduo, ambos em 70 oC e 240 bar, condição selecionada para os experimentos com cossolventes. Os solventes etanol e acetato de etila foram utilizados nas concentrações de 1, 3 e 5 % (v/v) junto ao CO2, proporcionando rendimentos de até 2,35 %. As extrações Soxhlet (360 min) e com líquidos pressurizados (40, 55 e 70 oC; 100 bar e 20 min) evidenciaram a afinidade dos compostos por solventes polares e o efeito positivo da temperatura sobre o rendimento, de 0,53 a 7,23 %. Um planejamento Box-Behnken foi empregado para avaliar efeitos da temperatura (40, 50 e 60 oC), razão volume de n-hexano/massa de madeira (10, 15 e 20 mL g-1) e potência ultrassônica nominal do equipamento (150, 300 e 450 W) sobre rendimento em óleo, obtendo-se, em 7 minutos de extração, até 83 % do rendimento obtido na técnica convencional em Soxhlet (1,57 %), com volume de solvente 2,5 vezes menor. Os compostos majoritários identificados no óleo da candeia foram os sesquiterpenos α-bisabolol, eremantina e costunolida, e o conteúdo do α-bisabolol no óleo foi favorecido pela menor densidade do CO2 supercrítico, sendo de até 74,5 % para a madeira de candeia e 50,6 % para o resíduo, ambos extraídos na condição de 70 oC e 160 bar. A adição dos cossolventes etanol e acetato de etila ao CO2 elevou o rendimento de α-bisabolol em até 41 %. Também aumentaram a quantidade de fenólicos totais no óleo e, consequentemente, sua capacidade antioxidante. O fracionamento do óleo por cromatografia em coluna foi eficiente para o isolamento do α-bisabolol. No entanto, diferentemente do óleo da madeira de candeia, este composto não foi efetivo na inibição do crescimento de Staphylococcus aureus. Em relação às cinéticas das extrações supercríticas, o modelo matemático de Sovová se ajustou aos dados experimentais em todas as condições utilizadas.

Dans cette étude, nous nous sommes intéressés aux propriétés physiques et chimiques de six accessions de Mammea americana afin de pouvoir identifier les accessions les plus prometteuses pour la vente en frais ou la transformation. Nous avons également cherché à évaluer l’activité antioxydante de la pulpe, identifier et quantifier ses composés phénoliques et optimiser leur extraction à l’aide de la technique assistée par ultrasons.Nos résultats montrent que les accessions étudiées présentent des caractéristiques physiques, physico-chimiques et fonctionnelles significativement différentes. Pavé 11, Lézarde et Ti Jacques sont intéressants pour la vente en frais, en raison de leurs fruits sucrés avec une teneur élevée en caroténoïdes et composés phénoliques totaux. Sonson, Pavé 11 et Lézarde présentent une adaptabilité à la transformation. La composition polyphénolique de la pulpe déterminée par HPLC-DAD et UPLC-MS, a mis en évidence la présence d’acides phénoliques, de tanins condensés, de flavonols et flavanols dans nos échantillons. D’autre part, les tests d’activité antioxydante (DPPH et ORAC) révèlent que Ti jacques est l’extrait le plus actif. Un plan d’expérimentation a été mis en œuvre afin d’optimiser l’extraction des polyphénols à l’aide d’une technique d’extraction assistée par ultrasons. Les résultats montrent que l’extrait obtenu est riche en polyphénols et contient les mêmes teneurs en acides phénoliques et flavonols comparé à celui obtenu par la méthode conventionnelle. De plus, l’extrait obtenu à l’aide d’un solvant « vert » possède de bonnes propriétés organoleptiques. / Our work focuses on the physical and chemical properties of six mamey apple cultivars in order to select elite cultivars suitable for food processing or as table fruit. The antioxidant activity of the fruit pulp, the identification and quantification of the polyphenols responsible for it, and ultrasound assisted extraction method were also investigated.According to our results, the postharvest routes for every cultivar could be different. Pavé 11, Lézarde and Ti Jacques were found to be good for consumption, giving sweeter fruits with high total phenolic and carotenoid contents. Sonson, pavé 11 and Lézarde had suitable characteristics for the manufacturing of mamey products. The polyphenolic composition of the pulp determined by HPLC-DAD and UPLC-MS showed the presence of phenolic acids, condensed tannins, flavonols and flavanols. The results of the antioxidant test (DPPH and ORAC) point out that the most antioxidant cultivar was Ti Jacques. The design and optimization of the ultrasound assisted extraction method has done for polyphenols extraction. The results showed that the polyphenols rich extract contains the same content of phenolic acids and flavonols in comparison to the conventional method. Additionally, the dry extract obtained with a “green” solvent, had good organoleptic properties.

Les lichens sont des organismes symbiotiques constitués d'un champignon (mycobionte) associé à une algue et/ou une cyanobactérie (photobionte). Leurs métabolites secondaires sont des molécules originales appartenant au groupe des depsides, depsidones, dibenzofuranes et présentent un intérêt pour la cosmétique et/ou la pharmaceutique en raison de leur propriété antibiotique, anti-inflammatoire, antioxydant, filtre UV. Nous avons choisi d'étudier le lichen Pseudevenia furfuracea qui est l'un des lichens utilisés en tant que matière première pour la parfumerie et la cosmétique (1900 tonnes / an), car il est d'une part abondant dans la nature et d'autre part, il possède des métabolites secondaires très variés. Classiquement, les extraits utilisés sont obtenus par extraction au reflux de solvants organiques; cette méthode à l'inconvénient d'induire des durées d'extractions relativement longues et est consommatrice en solvants. L'objectif de notre travail est d'extraire les métabolites secondaires d'une manière sélective et innovante tout en diminuant la durée d'extraction. Pour cela, nos travaux reposent sur l'extraction assistée sous micro-onde (EAM) combinée ou non aux liquides ioniques. Dans ce dessein, deux familles de liquides ioniques (LIs) "hydrophiles" et "hydrophobes" ayant un cation imidazolium et pyridinium ont été synthétisés. Trois différentes préparations de lichen (mixé, broyé au mortier et broyé planétaire) ont été effectuées en faisant varier la granulométrie et chaque préparation a été étudiée par microscopie électronique à balayage. L'optimisation de l'EAM a été effectuée à une température d'extraction optimale de 75 °C et a permis de générer un énorme gain de temps (24 h sous conditions classiques contre 15 min sous irradiation micro-onde). Une étude comparative des taux d'extraction entre l'EAM et l'extraction en condition classique a été éffectuée par analyse au spectrodensitomètre CAMAG®, celle-ci a montré que la première est plus performante dans la plupart des cas. L'utilisation des liquides ioniques a mis en évidence l'existence d'une sélectivité d'extraction en fonction de la structure des LIs qui résulte d'interactions intermoléculaires entre les LIs et les substances extraites. L'effet de chaque liquide ionique sur la dégradation d'un des métabolites, en particulier l'atranorine, a également été étudié. Également, les interactions entre un liquide ionique et la surface du lichen ont été étudiées par mesure d'angle de contact et par les mesures de Brunauer Emett et Teller. Une extraction à plus grande échelle a été réalisée pour étudier la reproductibilité de la méthode et la possibilité de recycler le liquide ionique. / Lichens are symbiotic organisms constituted of fungus (mycobiont) associated to algae and/or cyanobacteria (photobiont). Their secondary metabolites are original molecules belonging to the group of depsides, depsidones, dibenzofurans. Lichens presented special interest for cosmetic and pharmaceutical industry due to their antibiotic, anti-inflammatory, antioxidant and UV filter properties. In this work we focused our study on Pseudevenia furfuracea lichen, which is intensively used as a raw material in perfumery and cosmetics (1900 tons/year), due to its large availability in nature as well as possessing various secondary metabolites. In this work we presented extraction of the secondary metabolites using a selective and innovative solventfree method in shorter extraction time in comparison to the conventional extraction methods requiring under reflux of large quantities of solvents with longer times for extraction. The proposed method is based on the use of microwave irradiation for extraction (MIE) associated to (or not) appropriate ionic liquids. Two kinds of hydrophilic or hydrophobic imidazolium- and pyridinium-based ionic liquids (ILs) were synthesized. Three different methods of grinding for lichen were used, leading to different particle size and the crushed products were observed by scanning electron microscopy (SEM). Heating optimization of MIE was performed during 15 min at optimal temperature (75 °C) (instead of 24 h under conventional heating). A comparative study of extraction rates between MIE and extraction with conventional heating was realized with a CAMAG® spectrodensitometer and results of analysis showed that MIE is efficient in most of the studied cases. The use of ionic liquids showed selectivity for extraction and it depended on the structure of ILs and also intermolecular interactions between ILs and extracted substances.Effect of each ionic liquid on the degradation of one of the secondary metabolites, atranorin, was also been studied. In addition, interactions between IL and the surface of the lichen surface were studied by measurements of the angle of contact and by Brunauer Emett and Teller measurements. Scale-up for extraction was carried out to investigate the reproducibility of the method and the possibility of reuse of the ionic liquid.