Vanillin (4-hydroxy-3methoxybenzaldehyde) is one of the most employed aromatic and flavoring additives in food and cosmetic industry. The industrial interest in vanillin could also apply to its biodegradation products. The microbial transformation of vanillin can open the possibility of new products with new areas of application for products related to vanillin. For example, vanillyl alcohol, vanillic acid and ferulic acid are currently used in the pharmaceutical or food industry. Some species reported to biodegrade vanillin into the related products vanillyl alcohol and vanillic acid, are: Brettanomyces anomalus and Saccharomyces cerevisiae. Moreover, certain microorganisms possess the ability to accumulate lipids when cultivated on different carbon sources, opening the possibility of microbial lipid production as another industrial application. The present investigation focuses on the optimization of extraction methods for vanillin biodegradation products, as well as identifying the isolates of a collection of microorganisms originating from the Faroe Islands that are amenable to being cultivated on a lignin-based media. Finally, the potential for microbial lipid accumulation was also studied. Two analytical methods, Thin-Layer Chromatography (TLC) and Gas Chromatography (GC) were employed for characterizing the biodegradation products obtained after 24 hours and 72 hours of culture in growth medium supplemented with 1 mM of vanillin. The results showed that after 24 hours of incubation, the model microorganism, strain FMYD002, had consumed some of the vanillin and transformed it into biodegradation products. TLC retention factors and GC chromatograms revealed that the main biodegradation product after 24 hours - when compared to a standard – is likely to be to vanillyl alcohol. Furthermore, vanillin and its biodegradation products were relatively temperature-stable based on a temperature test of supernatant from a 24-hour culture, however, when the 72-hour culture had been subjected to the highest temperature (60 °C) some spontaneous decomposition occurred. The biodegradation pattern of the 72-hour culture evidenced by TLC revealed two additional biodegradation products, one of which migrates in a similar fashion to vanillic acid. After 72 hours of incubation, the biodegradation product presumed to be vanillyl alcohol was no longer observed. Acidification tests showed that the best route for extraction of the product believed to be vanillyl alcohol is to adjust the extracted sample to a pH of 9. The cultivation test of the isolates in media prepared from different lignin-based residual products showed that 26 out of 60 initial strains grew regardless of the concentration of lignosulfonates and vanillin. Moreover, 17 strains grew in nitrogen-limited medium. Eight of the strains accumulated lipids. A preliminary categorization of isolates based on their colony morphology and capacity of growth on different substrates showed that to some extent, their morphology can predict the ability to grow on lignin- and vanillin-based media. This could help future scientists to easily screen for and select isolates with interesting activity for the ligno-cellulose industry.

Ces travaux de thèse traitent de l’utilisation d’une molécule polycyclique, l’acide abiétique, issu de la colophane, et de dérivés phénoliques potentiellement dérivés de la lignine, pour la synthèse de polymères rigides bio-sourcés. Dans les deux cas, des monomères symétriques et difonctionnels sont élaborés par réaction de dimérisation des précurseurs bio-sourcés puis testés en polymérisation. D’une part, les dimères de l’acide abiétique obtenus par un mécanisme cationique possèdent des structures mal définies qui compliquent leur polymérisation. Ces dimères ont alors été estérifiés avec de l’undécénol afin d’obtenir un composé bis-insaturé qui est ensuite polymérisé par ADMET. D’autre part, un procédé de dimérisation de molécules phénoliques, potentiellement issues de la lignine, a été développé par voie enzymatique utilisant une laccase. L’avantage majeur de ce procédé ‘vert’ réside dans la séparation très simple entre le monomère, soluble, et son dimère, insoluble. Ces dimères ont ensuite été modifiés chimiquement afin de constituer une bio-plateforme de composés biphényles fonctionnels. Ces composés ont été utilisés pour la synthèse de polyesters, polyamides et résines époxy qui présentent des propriétés thermiques et thermomécaniques remarquables. / The aim of this thesis is to investigate new biobased rigid synthons for the synthesis of polymers with high thermomechanical properties. A polycyclic biobased molecule, i.e resinic acids, and phenolic compounds potentially derived from lignin, such as vanillin were selected. Both classes of substrates were dimerized in order to get difunctional symmetric synthons. On the one hand, abietic acid dimers synthesized via a cationic mechanism presented an ill-defined structure. To avoid reactivity issues, dimers with reactive terminal double bonds were successfully synthesized by esterification of abietic acid dimers with undecenol and polymerized by ADMET methodology. On the other hand, we developed a “green” process to dimerize phenolic compounds derived from lignin in large quantity and high yield via enzymatic catalysis using a laccase. The main advantage of this method is that the phenolic monomer is soluble in the reaction medium while the dimer precipitates. After chemical modifications of the dimers, we built a functional bio-platform of biphenyl derivatives. The latter were then used for the synthesis of polyesters, polyamides and epoxy resins which exhibited remarkable thermal and thermomechanical properties.

Le remplacement de monomères d'origine pétrosourcée par des analogues biosourcés améliore la durabilité et diminue la dépendance aux ressources fossiles. De plus, de nouvelles caractéristiques et propriétés sont souvent découvertes. Les polyesters aliphatiques biosourcés ont déjà partiellement remplacé les produits traditionnels. Dans le contexte du projet Sorago, une résine entièrement biosourcée pour les revêtements de prélaquage des produits intérieurs a déjà été introduite sur le marché (Estetic® bio Air, Arcelor Mittal). Pour permettre l'utilisation du produit dans des applications extérieures, sa résistance à la lumière UV et à l'humidité sont à améliorer. Cela pose deux problèmes : Une disponibilité limitée de monomères pouvant introduire de la rigidité dans la résine et la relation entre la structure de la résine et sa dégradation. La vanilline a été choisie comme synthon pour la gamme des monomères rigides et biosourcées. La transformation de sa fonction aldehyde par réaction de Perkin et sa réactivité a été examinée. Dans une série des copolymerisations, l'influence des conditions de réaction sur la composition du produit final a été proposée. Une relation structure-propriétés concernant la température de la transition vitreuse et la viscoélasticité des plusieurs monomères biosourcées a été établie, et comparée avec celle des monomères petrosourcées. Une série des prototypes avec des propriétés très variées a été soumise à un test de vieillissement rapide. Leur dégradation a été suivie sur la base de leur rétention de brillance, par FTIR et par des tests de µ-dureté et d'épaisseur des films. La performance des prototypes biosourcés s'est révélée inférieure à celle d'une résine standard pétrosourcée mais aucune évidence qui suggère que cela est du à la présence des monomères biosourcées n'a été détectée. Cela suggère que la création d'une résine biosourcée et suffisamment durable pour l'extérieur sera possible / Moving away from petroleum and towards biobased materials not only leads to greater sustainability and lower dependence on diminishing fossil resources, but can also catalyse the discovery of new properties. Aliphatic polyesters based on renewable resources have already started to replace traditional products. Within the Sorago project, a fully biobased resin for interior coil coatings has recently been proposed on the market (Estetic® Bio Air, Arcelor Mittal). In order to extend the possible use of the biobased product to exterior applications, an improvement of its resistance to humidity and UV radiation is crucial. This presents two challenges: The limited availability of monomers which provide rigidity in the resin structure and the relationship between the resin composition and its weatherability. Vanillin was chosen as a possible extension to the range of rigid, biobased monomers for polyesterification reactions. The transformation of its aldehyde and its reactivity was studied in terms of catalytic activation and through a series of copolymerisations which revealed the influence of the reaction conditions on the composition of the product. A structure-property relationship concerning the coating glass transition temperature and visco-elastic behaviour of the coating was furthermore established for a series of renewable monomers and contrasted with petroleum based equivalents. Series of prototypes with a wide variety of properties were then subjected to accelerated weathering tests. Their degradation was followed directly by gloss retention and different mechanisms were revealed using FTIR, µ-hardness and film thickness measurements. While the performance of the biobased coating was subpar, no evidence linking its degradation to the presence of renewable monomers was found, suggesting that the creation of a sufficiently durable and renewable exterior coating will be possible

Siekiant efektyvaus propolio fenolinių junginių poveikio odoje, svarbu sumodeliuoti veiksmingai šiuos junginius atpalaiduojančias ir tiekiančias į odą puskietes sistemas su propolio produktais. Darbo tikslas – pagrįsti puskiečių formų su propolio produktais modeliavimo principus, optimizuoti eksperimentines puskietes formas ir suformuluoti kokybės modelį, remiantis biofarmaciniais tyrimais. Įvertinta atskirų fenolinių rūgščių (vanilo, kavos, p-kumaro, ferulo rūgšties) ir vanilino skvarba į žmogaus odą ex vivo iš vandeninės propolio ištraukos ir eksperimentinių propolio puskiečių formų: tepalo, vanduo-aliejus tipo kremo, hidrogelio, aliejus-vanduo tipo gelifikuoto kremo. Patvirtintas aktyvus puskietės sistemos vaidmuo, atpalaiduojant ir darant įtaką propolio veikliųjų junginių skvarbai į odą. Įvertintas tirtų fenolinių junginių pasiskirstymas odos sluoksniuose (epidermyje ir dermoje), kuris susietas su skirtingu jų lipofiliškumu. Santykinai lipofiliniai junginiai (ferulo ir p-kumaro rūgštis) kaupėsi epidermyje, o santykinai hidrofiliniai junginiai (vanilo rūgštis ir vanilinas) migravo į dermą. Kavos rūgštis, kurios tirtuose propolio produktuose yra mažesnis kiekis negu kitų fenolinių rūgščių, nustatyta tik epidermyje. Pritaikytas eksperimentų planavimas vaisto formų sudėties optimizavimui. Optimizavimo parametrai leido prognozuoti propolio veikliųjų junginių atpalaidavimą iš tirtų puskiečių sistemų. / In order to achieve a desired effect of propolis phenolic compounds in the skin, it is important to develop semisolid systems with propolis products that would efficiently release and deliver these compounds into the skin. The aim of the study is to justify the modeling principles of semisolid formulations with propolis products, to optimize experimental semisolid formulations, and to formulate a quality model based on biopharmaceutical studies. The penetration of individual phenolic acids (vanillic, caffeic, p-coumaric, and ferulic) and vanillin from aqueous propolis extract and experimental propolis semisolid formulations (ointment, water-in-oil cream, hydrogel, and oil-in-water gelified cream) into the human skin ex vivo have been evaluated. An active role of the semisolid system in releasing and influencing the penetration of propolis active compounds into the skin has been confirmed. The distribution of investigated phenolic compounds in the layers of skin (epidermis and dermis) was evaluated and linked to different lipophilicity. Relatively lipophilic compounds (ferulic and p-coumaric acids) accumulated in the epidermis and relatively hydrophilic compounds (vanillic acid and vanillin) migrated to the dermis. Caffeic acid, which was present in analyzed propolis products at lower quantities as compared with other phenolic acids, was determined only in the epidermis. The design of experiments was applied for the optimization of the composition of dosage forms. Optimization... [to full text]

La chimiothérapie conventionnelle est principalement constituée d’agents pro-apoptotiques. Or, de nombreux cancers sont intrinsèquement résistants à l’apoptose et cela explique en grande partie les mauvais pronostics associés à certains cancers, dont les cancers métastatiques, en raison de leur résistance aux chimiothérapies pro-apoptotiques. La thématique de ce travail s’inscrit dans la recherche de molécules présentant des modes d’actions différents afin de vaincre les mécanismes de résistance des cellules cancéreuses. <p><p>Une nouvelle série de composés di- et trivanilliques a ainsi été déclinée. La structure de ces composés est inspirée de molécules naturelles divanilliques étudiées pour leurs propriétés anti-falciformation dans la drépanocytose. Notre stratégie a été de transposer l’activité présumée de ces composés sur le cytosquelette des érythrocytes falciformes au niveau de la prolifération et de la migration des cellules cancéreuses. A cette fin, des méthodes pour analyser l’activité antitumorale de cette série de nouveaux composés ont été mises en place.<p><p>In vitro, les composés que nous qualifions d’actifs inhibent la croissance d’une dizaine de populations cellulaires cancéreuses distinctes à des valeurs inhibitrices de croissance à 50 % (indice IC50) de l’ordre de 30 µM. Les dérivés trivanilliques se classent parmi les composés les plus actifs de la série, en particulier le composé trivanillique chloré 13c qui exerce un effet cytostatique sur les lignées cellulaires cancéreuses analysées tout en présentant un certain taux de biosélectivité vis-à-vis des cellules normales. Nous avons ainsi consacré une partie de ce travail à approfondir la compréhension du mécanisme d’action du composé 13c et à le comparer à ses analogues de synthèse pour tenter d’établir une relation de type structure-activité.<p><p>Le dérivé 13c est cytostatique car il interfère avec le processus mitotique et il inhibe à plus de 75 % l’activité de 26 kinases à la concentration de 2 µM qui est donc plus de dix fois inférieure à la concentration inhibitrice IC50 moyenne de 30 µM rapportée ci-avant. Huit de ces 26 kinases sont directement impliquées dans l’organisation du cytosquelette d’actine et notamment dans les processus de cytokinèse. Parmi les kinases dont l’activité est la plus fortement modifiée par le composé 13c figurent les Aurora kinases qui sont de puissants contrôleurs de la cytokinèse. Nos résultats montrent également que l’activité cytostatique du composé 13c entraînant une désorganisation du cytosquelette d’actine pourrait être induite non seulement par l’inhibition de l’activité de certaines kinases mais aussi par des modifications induites par ce produit au niveau de l’homéostasie du calcium intracellulaire.<p><p>L’efficacité des agents chimiothérapeutiques est souvent altérée par une résistance tumorale intrinsèque appelée résistance multidrogue (le phénotype MDR). In vitro, le composé 13c s’est montré tout aussi efficace sur des lignées cancéreuses possédant cette résistance multidrogue que sur des cellules cancéreuses sensibles aux agents chimiothérapeutiques. De même, diverses lignées cellulaires résistantes aux stimuli pro-apoptotiques sont également sensibles à l’activité inhibitrice de croissance in vitro du trivanillate 13c. <p><p>Enfin, l’activité du composé 13c a été testée in vivo sur un modèle de pseudométastases pulmonaires issues du mélanome B16F10 murin. Les tumeurs pulmonaires présentent une cible intéressante pour le composé 13c au vu de son activité anti-tyrosine kinase comprenant la kinase EGFR et ses formes mutées EGFR-L858R et EGFR-T790M fréquemment retrouvées au sein des cancers du poumon non-à-petites-cellules (NSCLC). Le principe actif a été administré dans les poumons par inhalation via un dispositif endotrachéal. La voie inhalée est avantageuse par rapport à la voie systémique pour l’administration du produit 13c car cette molécule possède des liaisons esters qui sont hydrolysables par les estérases plus présentes au niveau des voies systémiques que dans les tissus pulmonaires. L’inhalation permet aussi de cibler mieux le site tumoral afin de réduire les dommages collatéraux. <p><p>Ce travail offre des perspectives au niveau de l’élaboration de formulations permettant d’augmenter la biodisponibilité de la molécule 13c. Une association d’un traitement au composé 13c et d’une chimiothérapie conventionnelle est envisagée car elle pourrait potentialiser les effets de ces deux traitements. <p> / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished

Vanilla planifolia, orchidée épiphite florifère, est la principale source naturelle de l'arôme de vanille. Largement utilisé dans les produits laitiers, les boissons, les pâtisseries et les parfums, cet arôme est le résultat d'un processus complexe : de huit à neuf mois après la fécondation des fleurs, les gousses matures sont récoltées et traitées pendant environ un an afin de libérer leur bouquet aromatique. Aujourd'hui, plus de la moitié de la production mondiale de vanille provient de Madagascar. Pour faire face à cette concurrence, les producteurs de la Réunion se tournent vers la production de vanille "haut de gamme". L'exploitation des vanilliers les plus intéressants du point de vue aromatique est donc favorisée. Toutefois, les programmes d'amélioration se heurtent au manque de connaissances sur la physiologie de la plante. Il devient alors essentiel de mieux comprendre les mécanismes physiologiques et biochimiques impliqués dans la production aromatique des gousses de V. planifolia. Dans ce travail de thèse, une analyse des métabolites présents dans les gousses vertes et les feuilles de vanille a été effectuée par Résonance Magnétique Nucléaire. Cette technique permet l'évaluation qualitative et quantitative des métabolites primaires (sucres, acides animés et organiques...) et secondaires (composés phénoliques...) présents dans la plante dans diverses conditions physiologiques : au cours du développement de la gousse, lors d'une infection virale, selon les saisons ou encore sur différentes accessions. / Vanilla planifolia, a flowering epiphitic orchid, is the major natural source of vanilla flavour. Largely used in dairy products, beverages, bakeries and perfume, vanilla flavour is obtained after a long process: from eight to nine months after flower pollinisation, mature pods are harvested and then prepered during about one year in order to release the characteristic vanilla aroma. Nowadays, more than half vanilla pods world production comes from Madagascar. To face the concurrence, a solution could be develop higher quality pods. Selection of the most aromatic vanilla plant is then preferred. Nevertheless, amelioration program are facing up to a lack of knowledge in vanilla plant physiology. It is now essential to understand more the physiological and biochemical mechanisms implied in the aromatic production of V. planifolia pods. In this thesis, a metabolomic analysis of vanilla green pods and leaves has been performed by nuclear magnetic resonance. This technique has allowed the qualitative and quantitative analysis of primary (sugar, amino and organic acids...) and secondary metabolites (phenolic compounds...) present in vanilla plant according to various physiological conditions: developing pods, viral infection, inter-accession or seasonal variation.

Thesis (PhD (Chemical Engineering))--Cape Peninsula University of Technology, 2020 / The use of bioproducts in different commercial sectors such as medicine, agriculture, cosmetics, food, and chemical industries motivates the need for easy production and recovery techniques of bioproducts at laboratory and pilot scale. This study aims at the production and recovery of some selected bioproducts using supercritical fluid extraction techniques. Three products are chosen as case studies: these are ethanol, acetoin, and vanillin, since the ease of separation is influenced by the concentration of the product in the broth, these compounds were selected based on their concentration in the fermentation broth, according to literature sources. A standard method was developed in a spectrophotometer for quantifying the targeted product in the broth, while the product recovery studies was carried out using a supercritical fluid extraction pilot plant. Saccharomyces and Bacillus species were chosen for the bioproduction of the selected bioproducts. Experimental design and statistical analysis of results were carried out using response surface methodology (RSM) and artificial neural network (ANN). Studies on each of the selected bioproducts are as justified in the paragraphs below. Bioethanol production has recently become an increasing trend in research, with a focus on increasing its economic viability. Hence, the need to develop a low-cost fermentation medium with minimum redundant nutritional supplements, thereby minimizing the costs associated with nutritional supplements whereby inoculum preparation becomes necessary for ethanol production. Corn steep liquor (CSL) in glucose fermentation by Saccharomyces Type 1 (ST1) strain and Anchor Instant Yeast (AIY), which are low-cost media, are used as replacements for yeast extract (YE). The fermentation process parameters were optimized using artificial neural networks (ANN) and the response surface methodology (RSM). The study shows that for CSL, a maximum average ethanol concentration of 41.92 and 45.16 g/L representing 82% and 88% of the theoretical yield were obtained after 36 h of fermentation in a shake flask for ST1 and AIY respectively. For YE, ethanol concentration equivalent to 86% and 88% of theoretical yield were obtained with ST1 and AIY respectively after 48 h. Although, ANN predicted the responses of ethanol yield better than RSM, optimum conditions for ethanol production were better predicted by RSM. The consumers’ preference for ‘naturally’ produced aromas drives the development of bioproduction of acetoin from glucose with a view to optimize its production. The results revealed that by using a cheap nitrogen source, corn steep liquor, the yield of acetoin was similar to those of yeast and beef extracts. Furthermore, it was shown that by using Box-Behnken design, the optimum parameters such as glucose concentration, corn steep liquor, and inoculum size to maximize the concentration of acetoin produced were 78.40 g/L, 15.00% w/v and 2.70% v/v respectively. The validated concentration of acetoin produced in a triplicate analysis, 10.7 g/L, was 0.06% less than the predicted value. Increasing awareness of consumers of healthy, eco-friendly flavors and fragrances motivates the bioproduction of vanillin. The interactive effects of three variables on vanillin yield were evaluated by response surface methodology (RSM) with Box-Behnken design (BBD) model. The results showed the optimum conditions for the biotransformation of ferulic acid into vanillin can be achieved with maximum overall desirability (D) of 1.0 and a significant (p<0.05) quadratic model with regression coefficient (R2) of 0.995. Corn steep liquor, initial ferulic acid concentration and pH significantly influence the concentration of vanillin in the broth. The results in triplicate experiments confirmed vanillin yield of 386 mg/L after validation, which was in agreement with the prediction of the model. The maximum vanillin yield of 384.40 mg/L was predicted when corn steep liquor, ferulic acid concentration and pH were 7.72 g/L, 2.33 g/L, and 9.34 respectively. Fermentation system in a bioreactor has been proven to be an efficient system for the study of controlled fermentation variables when compared to a shake flask study. The influence of agitation, aeration, time and pH were analysed by Taguchi orthogonal array design for the upscale of acetoin in a bioreactor. The optimized parameters in 1.3L of fermentation vessel were as follows: 300 rpm agitation, 1.5 slpm aeration; 2 days’ fermentation time and 6.5 pH value. Agitation with above 70% was the most contributing factor and other variables were less than 30% in the percentage analysis of variance of each fermentation variables in the batch study of acetoin. A fourfold gain in acetoin titre (42.30 g/L) was obtained with the same substrate concentration in a lab-scale bioreactor on scaling up when compared with the shake flask batch study. The validated acetoin concentration of 41.72 g/L was obtained after a triplicate experiment to confirm the possibility of reproducing acetoin using the optimized conditions. Many separation techniques have been proven to recover value-added products from fermentation broth with a preference for several methods above other and new techniques that are emerging. Supercritical fluids separation using CO2 is one such technique. The feasibility of acetoin concentration and recovery was studied in supercritical CO2 pilot plant with pressure ranges of 100 to 300 bar, CO2 feed rate of 5 to 15 kg/h, at a process temperature of 37 and 80 °C in simulated and fermentation broth, respectively. The validated conditions for the fractionation of acetoin by supercritical fluid extraction (SFE) were determined as follows: extraction pressure, 300 bar; CO2 feed rate, 15 kg/h; extraction temperature 37 °C; and fractionation time of 30 minutes. At these operating conditions, the percentage recovery of acetoin with respect to the feed solution at the raffinate for the simulated and actual ermentation broth was 77.8% (0.20 g/L) and 77% (0.15 g/L) respectively. A two-fold extract increase was obtained after 30 minutes of fractionation. The study provides the technical feasibility and the base case data which are critical to the development and design of processes for production and recovery of acetoin. The lesson gleaned from this study may be extended to develop processes for the production and recovery of other bioproducts (ethanol and vanillin).

No description available.

Studies of biodegradation in lignins by basidiomycetes yeasts show the conversion of lignin in various degradation products among which vanillin, a valuable substance, suggested to be a strong inhibitor of both fermentation and growth of yeasts, stands. Sporidiobolales yeasts used in these experiments were aimed to be identified by their highly conserved ITS region as well as studied in vanillinsupplemented medium through, vanillin-supplemented plates, TLC and Neubauer’s chamber to find out which, among the several isolates tested, were the most resistant ones, understand how they take up vanillin and how their growth is affected by the presence of the phenolic compound. Two strains were identified as Rhodotorula babjevae. One of them, L4, together with LS22, Rhodosporidium kratochvilovae, could withstand and biodegrade high concentrations of vanillin, producing biodegradation products with Rf values similar to the ones know for vanillic acid and vanillyl alcohol. Better growth in medium supplemented with small doses of vanillin was found, as well as disparity among the same species and their metabolic features, therefore, herbicides resistance was suggested as a reason for strains divergence. Further morphological-species comparison could also describe if there exist a relation between them. / Estudios sobre la biodegradación de ligninas por levaduras basidiomicetes muestran la conversión de lignina en distintos productos de degradación, entre los cuales se encuentra la vainillina, un fuerte inhibidor de la fermentación y el crecimiento de levaduras. Las levaduras Sporidiobolales utilizadas en estos experimentos han intentado ser identificadas a través de la región ETI, muy conservada, además de estudiadas en medios suplementados con vainillina mediante placas suplementadas con vainillina, CCF y cámara de Neubauer para averiguar cuáles son las cepas más resistentes, entender cómo metabolizan la vainillina y cómo su crecimiento se ve afectado por la presencia de dicho compuesto. Dos cepas fueron identificadas como Rhodotorula babjevae. Una de ellas, L4, junto con con la cepa LS22, Rhodosporidium kratochvilovae, pudieron soportar y biodegradar elevadas concentraciones de vainillina, originando productos de biodegradación con valores de Rf similares a los del ácido vanílico y alcohol vanílico previamente conocidos. Se encontró un crecimiento mejor en medios suplementados con pequeñas dosis de vainillina además de una disparidad entre mismas especies y sus características metabólicas, así, herbicidas han sido sugeridos como una posible causa en dicha divergencia. Una futura comparación morfología-especie podrá describir si existe relación entre ambos.

Överkonsumtionen av engångsartiklar i fossilbaserad plast är ett av dagens stora miljöproblem. Således finns en efterfrågan på strategier för framställning av biobaserade plaster i allmänhet och härdplaster i synnerhet. Tidigare forskning har visat att vanillin-baserade resin, genom UV-härdning och dynamisk iminkemi, kan användas i framställningen av härdplaster som är termiskt bearbetningsbara, kemiskt återvinningsbara och självläkande. Följaktligen är Digital Light Processing (DLP) 3D-utskrivning en möjlig och flexibel friformframställningsmetod med stor noggrannhet för sådana härdplaster.  Mot denna bakgrund framställdes, i detta projekt, tre olika UV-härdbara, biobaserade monomerer, i form av vitrimerresin, genom en tvåstegsreaktion: metakrylering av vanillin följt av iminbildning med tre olika aminer (etylendiamin, EDA; 2,2′-etylendioxi bisetylamin, EDEA och trimetylolpropan trispolypropylenglykol aminterminerad eter, T-403). De tre olika monomererna analyserades för att identifiera den mest lämpade för friformframställning av härdplast med DLP 3D-printning. Monomeren framställd med EDA kunde inte UV-härdas till en härdplast. De två andra monomererna, å andra sidan, härdades framgångsrikt till härdplaster med god termisk stabilitet (upp till ungefär 300 °C) samtidigt som de var termiskt bearbetningsbara. Vidare visade dessa härdplaster lovande resultat vad gäller självläkning och kemisk återvinningsbarhet. Härdningen av monomeren syntetiserad med EDEA krävde minst tidsåtgång. Utöver detta visade denna härdplast god stabilitet i ett flertal vanliga lösningsmedel samtidigt som den, till följd av dess dynamiska iminbindningar, kemiskt kunde återvinnas i hexylamin. Slutligen visades det hur detta resin framgångsrikt kunde användas i DLP 3D-utskrivning av härdplast. / One of the main causes of the petrochemical depletion is the overconsumption of single-use plastic products. New strategies based on the production of plastics (in particular thermosets) starting from bio-based resources are, therefore, demanded. Previous research has shown how vanillin-based vitrimer resins can be photocured into thermally reprocessable, chemically recyclable and self-healable imine thermosets; and the potential of the light-assisted 3D-printing techniques for the photocuring of resins with great accuracy and flexibility.  In this study, three different photocurable biobased vitrimer resins were synthesized through a two-step procedure involving the methacrylation of vanillin and the Schiff-base reaction with two different diamines (ethylenediamine, EDA; 2,2′-(Ethylenedioxy) bis(ethylamine), EDEA) and a triamine (trimethylolpropane tris[poly(propylene glycol), amine terminated] ether, T-403). The resins were analyzed in order to find the most suitable one for DLP 3D-printing. The resin with EDA, as diamine, could not be successfully UV-cured into a thermoset. The other two thermosets showed good thermal stability, up to about 300 °C, while still being thermally reprocessable. In addition, the thermosets were promising in terms of self-healability and chemical recyclability. The thermoset obtained from the Schiff-base resin synthesized with the diamine EDEA provided the shortest curing time. This resin also displayed good solvent resistance against common solvents and potential chemical recyclability in hexylamine through an imine exchange reaction. As a final step, the possibility to obtain tridimensional thermosets by curing this resin with a DLP 3D-printing was successfully demonstrated.