A Uncaria tomentosa (Willd.) DC., comumente conhecida como unha de gato ou cat´s claw, é uma planta endêmica da Amazônia Peruana. Devido às suas propriedades terapêuticas, seus extratos e derivados são comercializados ao redor do mundo. As propriedades medicinais são atribuídas aos glicosídeos do ácido quinóvico, polifenois e especialmente aos alcalóides oxinólicos pentacíclicos. Assim, a mitrafilina é o principal alcalóide presente nos extratos da planta e, portanto, é o marcador químico de suas formulações comerciais. O processo de extração é uma etapa importante na padronização de seus extratos e, considerando a falta de estudos a respeito de sua influência sob o perfil fitoquímico, amostras de casca de unha de gato foram extraídas por meio de maceração dinâmica e extração assistida por micro-ondas. O objetivo desse estudo foi avaliar a influência dos fatores envolvidos no processo extrativo a respeito de sua composição química, atividade anti-inflamatória e antioxidante. Devido ao grande número de fatores de extração a serem avaliados, um planejamento experimental do tipo Placket Burman foi selecionado e os fatores escolhidos nessa etapa foram: porcentagem de planta em solvente, temperatura e tempo de extração. Adicionalmente, através de um planejamento Box Behnken, as condições ótimas de extração foram delineadas na segunda etapa do estudo. O tempo e a porcentagem de planta em solvente foram fatores significantes para a extração assistida por micro-ondas. Entretanto, o conteúdo de mitrafilina nesses extratos foi reduzido - comparativamente ao seu conteúdo total presente nas amostras analisadas - e, portanto, mais estudos são necessários para otimizar o seu rendimento. Além disso, o extrato otimizado foi avaliado quanto à capacidade anti-inflamatória, em um teste de edema de pata induzido por carragenina e apresentou uma capacidade inibitória na concentração de 0,57 mg de mitrafilina/ Kg de rato. Por conseguinte, tais achados confirmaram a sua atividade anti-inflamatória. Os resultados obtidos a partir da extração por maceração dinâmica sugerem que o alcalóide é facilmente extraído, pois não foi afetado por nenhuma das variáveis experimentais. Adicionalmente, os extratos apresentaram maior conteúdo de mitrafilina - comparativamente aos resultados observados na extração por micro-ondas. Entretanto, devido ao menor tempo empregado na extração assistida por micro-ondas, outros estudos são necessários a fim de otimizar a extração desse alcalóide por esse método. O extrato otimizado sob as condições de maceração dinâmica foi seco em spray drying e, utilizando um planejamento de mistura do tipo simplex-centroid, o efeito de diferentes misturas de três adjuvantes foi avaliado: Dmanitol, maltodextrina e Aerosil. Embora os extratos secos com Aerosil e maltodextrina tenham prevenido a degradação de mitrafilina - quando comparado ao extrato seco sem excipiente - a secagem resultou em elevada perda no conteúdo de alcalóide e também propriedades farmacotécnicas inadequadas. Tais observações sugerem que, mesmo em condições amenas de secagem, há a degradação do alcalóide. Portanto, tais resultados reforçam a necessidade de avaliações complementares a fim de prevenir a ocorrência de tais eventos / The Uncaria tomentosa (Willd.) DC. commonly known as unha-de-gato or cat´s claw is an endemic plant from the Peruvian Amazon. Due its therapeutic properties, the crude drug and a variety of extracts are commercialized worldwide. The healing properties are attributed to the glycosides of quinovic acid, polyphenols, and especially to the pentacyclic oxindole alkaloids. Thereby, mitraphylline is the main alkaloid present in the bark extract of U. tomentosa, and therefore, is the chemical marker of commercial formulations derived from the plant. The extraction process is an important step in the standardization of plant extract and considering the lack of studies that relate the influence of extractive processes in phytochemical profile of the cat´s claw extracts, the bark samples were extracted by dynamic maceration and microwave assisted extraction. The study aimed evaluate the influence of the extraction factors on the chemical composition, antioxidant and anti-inflammatory activities of the extracts from cat \'s claw barks. Due to the wide number of possible extraction factors to be evaluated and the lack of knowledge about the importance of this factor effects on U. tomentosa extract, the Placket Burman factorial design was selected and the experimental factors chosen in this step were: % plant solvent ratio, temperature and extraction time. Through a Box Behnken planning the optimal extraction conditions of cat´s claw bark will be outlined in the second stage of this work. The time and % plant solvent ratio were significant factors for microwave assisted extraction. However, the contents extracted of mitraphylline have been reduced - compared to the total yield of the plant - and, therefore, more studies are needed to optimize the alkaloid yield. The extract from the optimized conditions, was evaluated in carrageenan-induced rat paw oedema, and presented inhibitory capacity in concentration of 0.57 mg of mitraphylline / kg of rat. Therefore, these findings confirm its anti-inflammatory activity. The results obtained in the extractions by dynamic maceration, suggest that the alkaloid is easily extracted and is not affected by experimental variables. In addition, compared to microwave extraction, this methodology allowed extracts with higher content of mitraphylline. However, in view of the shorter extraction time employed in microwave extraction, other reviews are needed to increase the extraction of mitraphylline, by this method. The extract optimized by the conditions under dynamic maceration was dried in spray drying and using a simplex-centroid mixture design, the effect of different mixtures of three adjuvants - D- mannitol, maltodextrin and Aerosil- were evaluated. Although dried extracts with the aid of Aerosil and maltodextrin slightly prevented the degradation of mitraphylline - as compared to the dry extract without excipient - the drying process resulted in high loss in the total content of this alkaloid and inadequate physical properties. Such observation suggests that, even under the mild drying conditions, there is degradation of the alkaloid. Therefore, these results reinforce the need for auxiliary evaluations to prevent the occurrence of such events.

Abstract Blackcurrants (Ribes nigrum L.) are widely consumed due to their favourable taste and health-promoting effects. The berries and extracts from different parts of the plant show anticarcinogenic, antioxidative and anti-inflammatory properties, and are effective in reducing the risk of cardiovascular disease and in promoting brain health. These health-promoting benefits are due to high concentrations of valuable compounds such as anthocyanins and flavonols in blackcurrants. However, these compounds are sensitive to heat and processing and some are lost when the berries are processed into products such as jams, purees and juices. Industrial processing of juices is a multistep process that typically includes enzyme treatment, pressing, pasteurisation, clarification and usually also thermal concentration. Alternative minimal processing technologies are required to preserve the health-promoting compounds in products by avoiding the use of high temperatures and extensive clarification. Integrated membrane technology, i.e. combined ultrafiltration and reverse osmosis, was used in this thesis for the production of blackcurrant juice concentrate. Pre-treatment methods, such as enzymatic treatment, ultrafiltration, enzymatic treatment combined with ultrafiltration and centrifugation to increase the filtration efficiency in reverse osmosis were evaluated. Processing was modelled to define the resistances, using the resistance-in-series model. The preservation and concentration of anthocyanins and flavonols were analysed. The results indicated that the main resistance in the reverse osmosis process was polarisation resistance, while membrane resistance was lower and fouling resistance was one order of magnitude lower than the other resistances. The filtration efficiency results showed that the highest flux was achieved by ultrafiltered blackcurrant juice, but that the resulting juices were substantially lower in anthocyanins and flavonols, which were retained on the ultrafiltration membrane. Therefore, replacing ultrafiltration with centrifugation as the clarification method for juices is recommended. Value-added processing of blackcurrant was conceptualised by valorisation of the marc left in the berry pressing process for extraction of anthocyanin compounds. Conventional extraction was compared with microwave-assisted extraction (MAE), with the latter optimised using response surface methodology to achieve maximum efficiency in extracting anthocyanins. The optimum parameters found for MAE were: microwave power 700 W, extraction time 10 minutes, pH 2 adjusted with hydrochloric acid and a solid to solvent ratio of 0.05. Conventional extraction showed the best results when carried out at 80 °C for 300 minutes in aqueous solution with pH 2 adjusted by hydrochloric acid. Under these conditions, recovery of anthocyanins was still 10% lower than with MAE for only 10 minutes of extraction time. / Tiivistelmä Mustaherukoita käytetään paljon niiden hyvän maun ja terveyttä edistävien vaikutusten ansiosta. Marjoilla ja marjakasvin eri osien uutteilla on osoitettu olevan antikarsinogeenisia, antioksidatiivisia ja tulehduksia estäviä ominaisuuksia ja ne ovat tehokkaita pienentämään sydän- ja verisuonisairauksia. Ne edistävät myös aivojen terveyttä. Marjojen arvokkailla yhdisteillä kuten antosyanideillä ja flavonoleilla on terveyttä edistäviä vaikutuksia. Mustaherukassa on runsaasti näitä yhdisteitä. Hillojen, soseiden ja mehujen prosessoinnissa menetetään näitä hyödyllisiä yhdisteistä, koska ne ovat herkkiä lämmölle ja prosessoinnin vaikutuksille. Mehujen prosessoinnissa käytetään entsyymikäsittelyjä, puristusta, pastörointia, selkeytystä ja usein myös lämpökonsentrointia. Tuotteiden terveyttä edistävien yhdisteiden säilyttämiseksi tarvitaan uudenlaisia hellävaraisia prosessointitekniikoita ilman korkeita lämpötiloja ja voimakasta selkeyttämistä. Tässä työssä tutkittiin yhdistettyjen kalvotekniikoiden kuten ultrasuodatuksen ja käänteisosmoosin käyttöä mustaherukkatiivistemehun prosessoinnissa. Esikäsittelymenetelmiä, mm. entsyymikäsittelyä, ultrasuodatusta, entsyymikäsittelyn ja ultrasuodatuksen yhdistelmää sekä sentrifugointia, arvioitiin käänteisosmoosin suodatustehokkuuden parantamisessa. Suodatusvastuksen määrittämiseksi prosessi mallinnettiin käyttäen sarja -vastus mallia. Antosyanidien ja flavonolien säilyminen ja konsentroituminen prosesseissa määritettiin. Tulokset osoittivat, että suurin vastus käänteisosmoosissa aiheutui polarisaatiovastuksesta, kun taas kalvon vastus oli pienempi. Mallinnus osoitti myös, että likaantumisen aiheuttama vastus oli yhtä magnitudia alhaisempi kuin muut vastukset. Suodatusteho osoitti, että suurin virtaus saavutettiin ultrasuodatetulla mustaherukkamehulla. Ultrasuodatetussa mehussa oli kuitenkin huomattavasti vähemmän antosyaniineja ja flavonoleja, mikä johtui näiden yhdisteiden tarttumisesta ultrasuodatuskalvoon. Näin ollen, tämän työn tulokset suosittelevat ultrasuodatuksen korvaamista sentrifugoinnilla mehun kirkastusprosessissa. Mustaherukkamehun tuotannossa muodostuu sivutuotteena ns. puristekakkua, joka sisältää runsaasti antosyaaneja. Työssä kehitettiin antosyaanien talteenottoa tästä sivutuotteesta vertaamalla tavanomaista uuttotekniikkaa mikroaaltoavusteiseen uuttoon. Prosessi optimoitiin vastepintamenetelmällä mahdollisimman suuren antosyaanien uuttotehokkuuden saavuttamiseksi. Optimaaliset parametrit saatiin mikroaaltoavusteisessa uutossa teholla 700 W, uuttoajalla 10 minuuttia, kiintoaines-liuotin -suhteella 0,05 pH-arvossa 2, mikä saavutettiin lisäämällä suolahappoa. Tavanomaisessa uutossa parhaat antosyaanisaannot saavutettiin suolahappo-vesiliuoksella pH-arvossa 2 uuttamalla 300 minuuttia lämpötilassa 80 °C. Antosyaanisaanto oli kuitenkin tavanomaisessa uutossa optimiolosuhteissa 10% pienempi kuin mikroaaltoavusteisessa uutossa 10 minuutin uuttoajalla.

Peanut skins are a low-value byproduct of peanut blanching operations. They have been shown to contain significant levels of phenolic compounds with demonstrated antioxidant properties. The effects of two types of extraction methods: solid-liquid extraction (SLE) and microwave-assisted extraction (MAE) on the recovery of phenolic compounds from peanut skins were investigated. Response surface methodology was used to optimize extraction conditions based on total phenolic content (TPC), ORAC (oxygen radical absorbance capacity) activity and <i>trans</i>-resveratrol content. The protective effect of peanut skin extracts (PSE) against hydrogen peroxide (H₂O₂)-induced oxidative stress in human brain microvascular endothelial cells (HBMEC) and the effect of PSE on lipid oxidation in commercial peanut butter were also evaluated. In the SLE method, EtOH was found to be the most efficient extraction solvent followed by MeOH, water and EA. Despite EtOH extracts having a higher TPC, samples extracted with MeOH demonstrated slightly higher ORAC activity. Resveratrol was identified in MeOH extracts but was not found in EtOH, water or EA extracts. In the MAE procedure, the maximum predicted TPC under the optimized conditions was 144 mg phenols/g skins compared to 118 mg/g with SLE. The maximum predicted ORAC activity was 2789 μmol TE/g as opposed to 2149 μmol TE/g with the SLE method. MAE was able to extract more phenolic compounds (with higher antioxidant activity) in a faster time than the SLE procedure. In addition, resveratrol was identified in PSE derived from MAE although at relatively low levels. PSE were found to have some protective effects against oxidative stress in HBMEC. Higher doses of PSE appeared to have a slightly cytotoxic effect. However, the data were highly variable which made it difficult to arrive at any definitive conclusions regarding the potential benefits of PSE in preventing oxidative damage to cells. In the PB experiment, hexanal levels over the storage period were not high enough for the samples to be considered oxidized. However, hexanal values of PB samples treated with PSE were lower than the control throughout storage, which suggests that PSE may provide some protection against oxidation of PB. / Ph. D.

<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.

<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.

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.

Chromatography and extraction techniques, and also chemiluminescence have been utilized to develop new rapid and informative tools in the evaluation of long-term properties and environmental effects of polymeric materials. Methods were developed for classification of materials and for early and rapid degradation detection. Degradable polyethylene films were classified on the basis of their incorporated prooxidant systems using chromatographic fingerprinting of carboxylic acids, the dominating type of degradation product. The fingerprints were also shown to be useful for prediction of the degradation states and evaluation of the degradation mechanisms. Classification and prediction models were obtained by Multivariate Data Analysis, where the diacids were grouped according to both their type of prooxidant system and their state of degradation. The use of total luminescence intensity (TLI) measurements was also investigated as a means of classifying films and for the early detection of degradation. Comparisons were carried out with common techniques, e.g. FTIR and DSC, after both thermal and UV oxidation. TLI gave an earlier detection of degradation and was more sensitive than carbonyl index and crystallinity measurements to relative differences in degradation between the materials. It furthermore offered complementary information regarding changes in activation energies during the course of the degradation. The results were compared with the chromatographic fingerprints. A new way to evaluate the low temperature long-term stabilisation efficiency of antioxidants was investigated. A prooxidant was used to obtain catalytic oxidation, instead of using thermal acceleration, to evaluate the stabilisation efficiency of antioxidants at low temperatures but still during reasonably short aging times. Comparisons were made between polypropylene films stabilised with primary antioxidants (Irganox 1076, Irganox 1010 and α-tocopherol) with and without the prooxidant manganese stearate at different temperatures. The relative efficiencies of the antioxidants obtained under prooxidant acceleration test correlated better than thermal acceleration test with the results of a long-term low temperature test. Additives in plastic packaging materials may affect the environment after migration from the packaging to e.g. their contents, especially if they consist of organic aqueous solutions or oils. The use of Solid-Phase Microextraction (SPME) for the specific task of extraction from an organic aqueous solution such as a simulated food or pharmaceutical solution consisting of 10 vol-% ethanol in water was investigated. Methods were developed and evaluated for extraction both with direct sampling and with headspace sampling. If the extraction method and temperature were selected to suit the concentration levels of the analytes, it was possible to quantify several degradation products simultaneously. Comparisons made with Solid Phase Extraction showed the advantage of SPME for this purpose. / QC 20100929

L’objectif de la thèse est une mise au point des espèces de Stephania répertoriées au Cambodge par l’étude systématique, phytochimique et pharmacologique. Du point de vue systématique, les travaux ont permis de répertorier sept espèces et deux variétés de Stephania au Cambodge : S. cambodica, S. japonica var. discolor et var. timoriensis, S. oblata, S. pierrei, S. rotunda (espèce-type), S. suberosa, et S. venosa. La clef de détermination établie lors de ce travail de thèse permet d’identifier ces espèces. D’après les résultats phylogénétiques, seul S. pierrei est monophylétique, ce qui représente moins de 10% des espèces de Stephania. L’étude chimique de cinq espèces a été réalisée par des méthodes chromatographiques (CLHP, UCLHP) et des méthodes spectroscopiques. Différents alcaloïdes ont été proposés comme marqueurs : la palmatine, la roémérine et la tétrahydropalmatine pour S. cambodica et S. rotunda, la cépharanthine, la tétrahydropalmatine et la xylopinine pour S. suberosa, la cépharanthine pour S. pierrei, la crébanine, et la tétrahydropalmatine pour S. venosa. Neuf alcaloïdes ont été isolés à partir du tubercule de S. cambodica, dont un nouveau composé dénommé «angkorwatine ». Une méthode d’éco-extraction des alcaloïdes assistée par ultrasons a été mise au point et optimisée par un plan d’expérience pour cette espèce. Une méthode analytique par UCLHP a été développée et validée pour le contrôle qualité de S. cambodica. Les résultats montrent que les extraits hydroéthanoliques obtenus par macération à partir du tubercule de S. suberosa, S. venosa et S. rotunda présentent une activité anti-inflammatoire importante (in vitro) avec un ratio anti-inflammatoire élevé. / The thesis aims to provide update on species of the genus Stephania recorded in Cambodia by systematic, phytochemical and pharmacological studies.The systematic study allowed to list seven species and two varieties of Stephania in Cambodia: S. cambodica, S. japonica var. discolor and var. timoriensis, S. oblata, S. pierrei, S. rotunda (type species), S. suberosa and S. venosa. The presence of S. japonica var. timoriensis and S. oblata is reported for the first time in Cambodia. According to the phylogenetic results, only S. pierrei is monophyletic, which represents less than 10% of species in the genus Stephania. Chemical studies on the tubers of five species were carried out using chromatographic methods (HPLC, UHPLC) and spectroscopic methods. Different isolated alkaloids have been proposed as markers: palmatine, roemerine and tetrahydropalmatine for S. cambodica and S. rotunda, cepharanthine, tetrahydropalmatine, and xylopinine for S. suberosa, cepharanthine for S. pierrei, crebanine, and tetrahydropalmatine for S. venosa. Nine alkaloids belonging to five classes were isolated from the tuber of S. cambodica and a new compound namely "angkorwatine" was described. Ultrasound assisted extraction of alkaloids was developed and optimized by Design of Experiment for this species. This innovative extraction is a good alternative to conventional methods. An analytical UHPLC method was developed and validated for the quality control of S. cambodica. Results show that hydroethanolic extracts obtained by maceration of S. suberosa, S. rotunda and S. venosa exhibit significant anti-inflammatory activity with high anti-inflammatory ratio (selectivity index).

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).