14,413 research outputs found

    Revisão taxonómica do género Calendula L. (Asteraceae - Calenduleae) na Península Ibérica e Marrocos

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    The genus Calendula L. (Asteraceae - Calenduleae) includes, depending on the author, 10 to 25 species, distributed mainly in the Mediterranean basin. The taxonomy of this genus is considered to be extremely difficult, due to a great morphological variability, doubtfull relevance of some of the characters used to distinguish its species (e.g. the life form: annual or perennial; the habit: erect or diffuse, shape of the leaves, indumentum, relative size of the capitula and colour of disc or ray florets, achene morphology), but also due to the hybridization and polyploidization. Despite the numerous studies that have been published, no agreement on the classification and characters used to discriminate between taxa has been reached. A taxonomic study of the genus Calendula was conducted for the Iberian Peninsula and Morocco, aiming at (1) access the morphological variability between and within taxa, (2) confirm the chromosome numbers, (3) increase the nuclear DNA content estimations, (4) re-evaluate taxa delimitations and circumscription, and (5) reassess, and redefine, the descriptions and characters useful to distinguish taxa. In order to achieve a satisfying taxonomic core, extensive fieldwork, detailed morphometric analysis, chorological, karyological and genome size studies were conducted. For the Iberian Peninsula, four species were recognized, including nine subspecies (between these two new subspecies were described). For Morocco, including some taxa from Algeria and Tunisia 13 species were recognized (two new species and a nomenclatural change), including 15 subspecies (among these eight new subspecies were described). To corroborate the results obtained and to evaluate the evolutionary relationships among taxa, phylogenetic studies using molecular methods, such as ITS, microsatellites or other molecular markers, should be used.O g√©nero Calendula L. (Asteraceae - Calenduleae) inclui, dependendo do autor, 10 a 25 esp√©cies, distribu√≠das essencialmente na bacia do Mediterr√Ęneo. A taxonomia deste g√©nero √© considerada extremamente dif√≠cil, devido √† grande variabilidade morfol√≥gica, discutivel relev√Ęncia de alguns dos caracteres utilizados para distinguir suas esp√©cies (por exemplo, a forma de vida: anual ou perene, o h√°bito: erecto ou difuso, a forma das folhas, o indumento, o tamanho e a cor dos cap√≠tulos e a morfologia dos aqu√©nios), mas tamb√©m devido √† hibridiza√ß√£o e poliploidiza√ß√£o. Apesar dos in√ļmeros estudos que foram publicados, n√£o foi alcan√ßado um acordo sobre a classifica√ß√£o e os caracteres utilizados para discriminar as suas esp√©cies. Um estudo taxon√≥mico do g√©nero Calendula foi realizado para a Pen√≠nsula Ib√©rica e Marrocos, com o objectivo de (1) verificar a variabilidade morfol√≥gica, (2) confirmar o n√ļmero de cromossomas, (3) aumentar as estimativas de conte√ļdo em ADN, (4) reavaliar a delimita√ß√£o e a circunscri√ß√£o dos taxa, e (5) reavaliar e redefinir as descri√ß√Ķes e caracteres √ļteis para os distinguir. Para alcan√ßar uma robust√™s taxon√≥mica satisfat√≥ria, foram realizados extensos trabalhos de campo, an√°lise morfom√©trica detalhada, abordagens corol√≥gicas, cariol√≥gicas e quanto ao conte√ļdo em ADN. Para a Pen√≠nsula Ib√©rica, quatro esp√©cies foram reconhecidas, incluindo nove subesp√©cies (entre essas duas novas subesp√©cies foram descritas). Para Marrocos, incluindo alguns taxa da Argelia e Tunisia, foram reconhecidas 13 esp√©cies (duas novas e uma mudan√ßa nomenclatural), incluindo 15 subesp√©cies (entre essas oito novas subesp√©cies foram descritas). Para corroborar os resultados obtidos e avaliar as rela√ß√Ķes evolutivas e filogen√©ticas entre os taxa, estudos que utilizem diferentes m√©todos moleculares, tais como ITS, microsat√©lites ou outros marcadores moleculares, devem ser utilizados.Apoio financeiro do Laborat√≥rio Associado CESAM - Centro de Estudos do Ambiente e do Mar (AMB/50017) financiado por fundos nacionais atrav√©s da FCT/MCTES e cofinanciado pelo FEDER (POCI-01-0145-FEDER-007638), no √Ęmbito do Acordo de Parceria PT2020, e Compete 2020Programa Doutoral em Biologi

    Pyrrolizidine alkaloids as contaminants

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    Pirolizidinski alkaloidi su tvari koje prirodno nalazimo u nekim biljnim vrstama (preteŇĺito vrste porodica Boraginaceae, Compositae/Asteraceae, Leguminosae/Fabaceae, Apocynaceae, Ranunculaceae, Scrophulariaceae), a produkt su njihovog sekundarnog metabolizma i primarno im sluŇĺe kao obrana od biljojeda. Njihova akutna toksińćnost, genotoksińćnost i potencijalni karcinogeni uńćinak na ljude poznati su veńá jako dugo vremena, a najńćeŇ°ńáe je toksińćnim uńćinkom u najveńáoj mjeri pogońĎena jetra. Nove spoznaje sve viŇ°e ukazuju na to da biljke koje prirodno ne sadrŇĺe pirolizidinske alkaloide uslijed rasta na istom staniŇ°tu kao i biljke koje ih sadrŇĺe, sluńćajne kontaminacije ili posljedińćnog kriŇĺanja vrsta, postaju biljke u kojima je moguńáe nańái odreńĎeni sadrŇĺaj pirolizidinskih alkaloida. Time se poveńáava sveukupna moguńáa izloŇĺenost pirolizidinskim alkaloidima i to iz viŇ°e razlińćitih izvora te raste moguńánost ispoljavanja Ň°tetnih uńćinaka po zdravlje, osobito kod redovitih potroŇ°ańća. Kako bi se ogranińćila izloŇĺenost pirolizidinskim alkaloidma, Komisija Europske unije je donijela odluku da se dozvoljeni sadrŇĺaj pirolizidinskih alkaloida dodatno ogranińći u proizvodima poput ńćajeva, biljnih infuzija, biljnih dodatka prehrani, pripravaka na bazi peludi i zańćinima te provedba te odluke kreńáe od 1. srpnja 2022. Iako o pirolizidinskim alkaloidima veńá puno toga znamo, svakodnevno dolazimo do novih spoznaja. VaŇĺno je naglasiti da je znanje mońá koja nam omoguńáava da u svjetlu novih spoznaja poduzmemo mjere koje su u naŇ°oj mońái kako bi se osigurala sigurnost i zdravlje opńáe populacije u ńćemu znańćajnu ulogu ima i sam farmaceut.Pyrrolizidine alkaloids are compounds that naturally occur in some herbal species (mostly species of plant families Boraginaceae, Compositae/Asteraceae, Leguminosae/Fabaceae, Apocynaceae, Ranunculaceae, Scrophulariaceae) and they are products of secondary metabolism that plants have developed as defense mechanism against insect herbivores. The acute toxicity, genotoxicity and carcinogenic potential for humans caused by pyrrolizidine alkaloids have been known for a very long time and usually liver is the most affected by its toxic effects. Recently, it has been shown that a lot of plants that naturally do not contain pyrrolizidine alkaloids are starting to show otherwise. Certain content of pyrrolizidine alkaloids has been found in plants due to the same habitat, contamination or crossbreeding of species. By this appearance, rate of possible exposure to pyrrolizidine alkaloids significantly increases and it is spread to more various sources what presents potential health hazard, especially in regular consumers. In order to restrict pyrrolizidine alkaloid exposure, The European Commission has brought the decision to additionally limit content of pyrrolizidine alkaloids that is allowed in products like tea, herbal infusions, herbal supplements, pollen based products and spices which will be implemented on 1. July 2022. Even though we know a lot about pyrrolizidine alkaloids, regularly we come to the new insights. It is important to emphasize the fact that knowledge is power which allows us to implement measures due to the new insights to ensure safety and preserve health of population in which significant role has the pharmacist

    Pyrrolizidine alkaloids as contaminants

    No full text
    Pirolizidinski alkaloidi su tvari koje prirodno nalazimo u nekim biljnim vrstama (preteŇĺito vrste porodica Boraginaceae, Compositae/Asteraceae, Leguminosae/Fabaceae, Apocynaceae, Ranunculaceae, Scrophulariaceae), a produkt su njihovog sekundarnog metabolizma i primarno im sluŇĺe kao obrana od biljojeda. Njihova akutna toksińćnost, genotoksińćnost i potencijalni karcinogeni uńćinak na ljude poznati su veńá jako dugo vremena, a najńćeŇ°ńáe je toksińćnim uńćinkom u najveńáoj mjeri pogońĎena jetra. Nove spoznaje sve viŇ°e ukazuju na to da biljke koje prirodno ne sadrŇĺe pirolizidinske alkaloide uslijed rasta na istom staniŇ°tu kao i biljke koje ih sadrŇĺe, sluńćajne kontaminacije ili posljedińćnog kriŇĺanja vrsta, postaju biljke u kojima je moguńáe nańái odreńĎeni sadrŇĺaj pirolizidinskih alkaloida. Time se poveńáava sveukupna moguńáa izloŇĺenost pirolizidinskim alkaloidima i to iz viŇ°e razlińćitih izvora te raste moguńánost ispoljavanja Ň°tetnih uńćinaka po zdravlje, osobito kod redovitih potroŇ°ańća. Kako bi se ogranińćila izloŇĺenost pirolizidinskim alkaloidma, Komisija Europske unije je donijela odluku da se dozvoljeni sadrŇĺaj pirolizidinskih alkaloida dodatno ogranińći u proizvodima poput ńćajeva, biljnih infuzija, biljnih dodatka prehrani, pripravaka na bazi peludi i zańćinima te provedba te odluke kreńáe od 1. srpnja 2022. Iako o pirolizidinskim alkaloidima veńá puno toga znamo, svakodnevno dolazimo do novih spoznaja. VaŇĺno je naglasiti da je znanje mońá koja nam omoguńáava da u svjetlu novih spoznaja poduzmemo mjere koje su u naŇ°oj mońái kako bi se osigurala sigurnost i zdravlje opńáe populacije u ńćemu znańćajnu ulogu ima i sam farmaceut.Pyrrolizidine alkaloids are compounds that naturally occur in some herbal species (mostly species of plant families Boraginaceae, Compositae/Asteraceae, Leguminosae/Fabaceae, Apocynaceae, Ranunculaceae, Scrophulariaceae) and they are products of secondary metabolism that plants have developed as defense mechanism against insect herbivores. The acute toxicity, genotoxicity and carcinogenic potential for humans caused by pyrrolizidine alkaloids have been known for a very long time and usually liver is the most affected by its toxic effects. Recently, it has been shown that a lot of plants that naturally do not contain pyrrolizidine alkaloids are starting to show otherwise. Certain content of pyrrolizidine alkaloids has been found in plants due to the same habitat, contamination or crossbreeding of species. By this appearance, rate of possible exposure to pyrrolizidine alkaloids significantly increases and it is spread to more various sources what presents potential health hazard, especially in regular consumers. In order to restrict pyrrolizidine alkaloid exposure, The European Commission has brought the decision to additionally limit content of pyrrolizidine alkaloids that is allowed in products like tea, herbal infusions, herbal supplements, pollen based products and spices which will be implemented on 1. July 2022. Even though we know a lot about pyrrolizidine alkaloids, regularly we come to the new insights. It is important to emphasize the fact that knowledge is power which allows us to implement measures due to the new insights to ensure safety and preserve health of population in which significant role has the pharmacist

    Diversity of Butterflies in Ledokombo Hillocks Jember, East Java, Indonesia

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    Ledokombo hillocks are small hills located in Jember, East Java that have natural resources and face habitat alteration such as plantation and mining.  However, a study of the diversity of butterflies has not been carried out in this area. We analysed the diversity of butterflies using the Shannon-Wiener diversity index (H’) and Pielou evenness index (E).  We identified 514 individuals from 34 species and demonstrated a moderate diversity of butterflies (H'= 1.907) in this area. Our study results could be used for sustainable ecological management of plantations in Ledokombo Hillocks, Jember, East Java.

    Current Perspectives in the Use of Phytotherapy for the Treatment of Breast Cancer

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    Breast cancer is  the most commonly diagnosed cancer leading to death among women worldwide. However, there is a significant improvement in the treatment of breast cancer. Today, the conventional treatment of breast cancer combines surgery , chemotherapy, radiation, targeted therapy, hormone therapy and immunotherapy.  Despite the advances in the diagnosis skills and in the treatment of breast cancer it has been observed that the recurrence rate experienced by breast cancer patients  is quite high. Moreover, the conventional treatment is often accompained with side effects. Thus, there is a need to search for new bioactive molecules.  Plant derived natural compounds can play a major role as sources of new bioactive substances for the treatment of breast cancer. Many plants have been reported to have anti-breast cancer properties. While investigations are being made to demonstrate the cytotoxic activities of many plants, the use of phytomedicine is not generating fully attention by mainstream practitioners. Some significant results were observed by patients with breast cancer history by combining phytotherapy and the conventional medicines.  Hence, plant extracts are more being used   in the treatment of breast cancer as adjuvant therapy. In this review we will present a summary of the advances of the researches on the efficacity of phytotherapeutic products when discussing their use in the treatment of breast cancer

    Picks in the Fabric of a Polyploidy Complex: Integrative Species Delimitation in the Tetraploid Leucanthemum Mill. (Compositae, Anthemideae) Representatives

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    Based on the results of a preceding species-delimitation analysis for the diploid representatives of the genus Leucanthemum (Compositae, Anthemideae), the present study aims at the elaboration of a specific and subspecific taxonomic treatment of the tetraploid members of the genus. Following an integrative taxonomic approach, species-level decisions on eight predefined morphotaxon hypotheses were based on genetic/genealogical, morphological, ecological, and geographical differentiation patterns. ddRADseq fingerprinting and SNP-based clustering revealed genetic integrity for six of the eight morphotaxa, with no clear differentiation patterns observed between the widespread L. ircutianum subsp. ircutianum and the N Spanish (Cordillera Cantábrica) L. cantabricum and the S French L. delarbrei subsp. delabrei (northern Massif Central) and L. meridionale (western Massif Central). The inclusion of differentiation patterns in morphological (leaf dissection and shape), ecological (climatological and edaphic niches), and geographical respects (pair-wise tests of sympatry vs. allopatry) together with the application of a procedural protocol for species-rank decisions (the ‘Wettstein tesseract’) led to the proposal of an acknowledgement of the eight predefined morphotaxon hypotheses as six species (two of them with two subspecies). Nomenclatural consequences following from these results are drawn and lead to the following new combinations: Leucanthemum delarbrei subsp. meridionale (Legrand) Oberpr., T.Ott & Vogt, comb. nov. and Leucanthemum ruscinonense (Jeanb. & Timb.-Lagr.) Oberpr., T.Ott & Vogt, comb. et stat. nov

    The phenolic constituents and antimicrobial activity of Xanthium spinosum (Asteraceae) extracts

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    Xanthium spinosum is a cosmopolitan annual herb used in traditional medicine worldwide. Although known from ethnobotanical studies, the species is scarcely investigated from the aspects of phytochemistry and biological activity. Therefore, the phenolic composition and biological activity of X. spinosum were examined. Plant specialised metabolites (phenolics) extracted from the roots, leaves and fruits with dichloromethane:methanol (1:1) were analysed by liquid chromatography mass spectrometry (LC-MS). In total 10 phenolic compounds were identified and quantified. Six compounds were common to all the extracts. Chlorogenic acid was the most abundant constituent in all the extracts (4.262 mg/g in the fruit extract, 0.820 mg/g in the leaf extract, and 0.540 mg/g in the root extract). The biological activity (antimicrobial and antibiofilm) of the extracts was tested against 12 microfungi and 12 bacterial strains by the microdilution method. All the extracts exhibited moderate antimicrobial and antibiofilm activity and inhibited the growth of most of the examined microorganisms. The obtained results indicate the potential role of the tested extracts in pharmacy and medicine

    Pollination patterns of flora and vegetation in northern Croatia with reference to Apis mellifera

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    Pollination patterns i.e. the proportions of entomophilous, anemophilous, autogamous and hydrophilous plant species and those useful for the European honey bee (Apis mellifera L.) in the flora and vegetation of northern Croatia have been determined. The survey included 507 plant taxa, belonging to 95 plant families. The results show that most plant species depend on insect pollination (73.6%), followed by self-pollination (30%), wind (25%) and water pollination (0.6%). For some plant species there are one, two or more modes of pollination; the largest group consists of pure insect pollination (43%), followed by both insect and self-pollination (27%), pure wind pollination (22%), insect and wind pollination (2.6%), and so on. Overall, 54% of plant species useful to European honey bees were found, of which 51% provide pollen and 47% nectar. These results suggest that A. mellifera could be a potential pollinator for about half of the flora. Analysis shows significant differences in pollination patterns among habitat types and that most entomophilous plant taxa are found in grassland, forest and ruderal sites, indicating that these habitats are most important for pollinators. Other characteristics of plant species, such as flowering time, plant family, life form and origin, were also analysed to determine a possible relationship with pollination

    Atractylenolide I inhibits EMT and enhances the antitumor effect of cabozantinib in prostate cancer via targeting Hsp27

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    ObjectiveTo investigate the effect of Hsp27 and the inhibitory effect of Atractylenolide I (ATL-1) on the proliferation of prostate cancer cell DU145 and PC-3.MethodsMTT assay was used to detect the inhibitory effect of silencing Hsp27 and ATL-1 on DU145 and PC-3 proliferation of prostate cancer cells. TUNEL detected the apoptosis rate of prostate cancer cell DU145 and PC-3 after silencing Hsp27 and ATL-1 treated. qRT-PCR was used to detect the changes of apoptosis related genes caspase-3, PARP, Bax and Bcl-2 in prostate cancer cell DU145 and PC-3 after the effect of silencing Hsp27 and ATL-1 treated. At the same time, the antitumor effect of ATL-1 combined with cabozantinib was analyzed.ResultsHsp27 was highly expressed in human prostate cancer. MTT assay showed that ATL-1 inhibited the proliferation of prostate cancer cells DU145 and PC-3 compared with the control group. TUNEL results showed that silencing Hsp27 and ATL-1 treated could significantly promote the apoptosis of prostate cancer cells DU145 and PC-3 compared with the control group. qRT-PCR results showed that compared with the control group, ATL-1 could promote the expression of caspase-3, PARP and Bax in DU145 and PC-3 prostate cancer cells. Inhibition of Hsp27 by ATL-1 reduced cell viability and induced apoptosis. ATL-1 inhibits the antitumor effect of Hsp27 - enhanced cabozantinib. Hsp27 regulates eIF4E and mediates cell protection.ConclusionSilencing Hsp27 inhibits EMT. ATL-1 can inhibit the malignant evolution of prostate cancer cells by inhibiting Hsp27/eIF4E. ATL-1 also enhanced chemosensitization of cabozantinib in prostate cancer

    Aditivación de materiales biodegradables mediante el uso de derivados de colofonia

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    [ES] El objetivo general de la presente tesis doctoral fue aditivar pol√≠meros biodegradables con colofonia y sus derivados mediante el uso de t√©cnicas de procesamiento convencionales y no convencionales. En esta tesis se presentan siete trabajos dentro de cuatro bloques de estudio que constituyeron los objetivos espec√≠ficos de la investigaci√≥n. En el primer bloque de estudio se realiz√≥ una caracterizaci√≥n comparativa de cinco colofonias de diferentes fuentes para determinar sus propiedades y establecer las diferencias entre cada colofonia para su posterior uso y aplicaci√≥n como aditivos sostenibles de pol√≠meros biodegradables. En el segundo bloque de estudio se aditiv√≥ colofonia en matrices de pol√≠meros biodegradables para lo cual se realizaron dos trabajos. En el primer trabajo se emple√≥ poli (butilen adipato-co-tereftalato) (PBAT) como matriz polim√©rica y colofonia (GR) y un pentaeritritol √©ster de colofonia (UT) como aditivos. El PBAT se mezcl√≥ con las resinas en varios contenidos y las formulaciones se procesaron por extrusi√≥n y un posterior moldeo por inyecci√≥n. En el segundo trabajo se emple√≥ poli(¬Ņ-caprolactona) (PCL) como matriz polim√©rica, y como aditivos se emplearon GR y cera de abeja (BW). Las formulaciones se prepararon por mezcla por extrusi√≥n y el procesamiento del material se llev√≥ a cabo por una t√©cnica no convencional que es la manufactura aditiva o impresi√≥n 3D.En el tercer bloque de estudio se realiz√≥ la aditivaci√≥n de materiales termopl√°sticos utilizando como base un pol√≠mero biodegradable de alto rendimiento ambiental y como aditivo colofonia y sus derivados. Como pol√≠mero base se emple√≥ almid√≥n termopl√°stico (TPS) y como aditivos de usaron los siguientes derivados de colofonia: colofonia sin modificar (GR), colofonia deshidrogenada (RD), colofonia modificada con anhidrido maleico (CM), pentaeritritol √©ster (LF) y √©ster de glicerol de colofonia (UG). La colofonia se mezcl√≥ con el TPS por extrusi√≥n y el procesamiento de las mezclas se llev√≥ a cabo por moldeo por inyecci√≥n. En el cuarto bloque se estudi√≥ la aditivaci√≥n de colofonia a matrices polim√©ricas mediante la t√©cnica de electropulverizaci√≥n. Se realizaron tres trabajos en los que se optimiz√≥ e implement√≥ el proceso de electrospulverizaci√≥n para la incorporaci√≥n de microesferas de colofonia en matrices polim√©ricas. En el primer trabajo se eval√ļo el uso de un proceso electrohidrodin√°mico como m√©todo de aditivaci√≥n de colofonia en matrices polim√©ricas. En el segundo trabajo se optimiz√≥ el proceso de electropulverizaci√≥n de colofonia a partir de 24 experimentos. Posteriormente, se depositaron microesferas de GR sobre pel√≠culas de PCL para obtener sistemas bicapa. Los resultados obtenidos revelaron un gran potencial para procesar f√°cilmente sistemas bicapa con alto inter√©s en aplicaciones agr√≠colas, de empaque y/o biom√©dicas sostenibles. Finalmente, en el tercer trabajo se us√≥ el m√©todo optimizado de electrospraying para aditivar microesferas de colofonia sobre la capa exterior de una mascarilla quir√ļrgica a base de polipropileno (PP), y se determin√≥ que el revestimiento de microesferas ayud√≥ a mantener la hidrofobicidad original de la capa exterior de la mascarilla quir√ļrgica incluso despu√©s de 6 horas de uso, aumentando en el tiempo de vida √ļtil de la mascarilla. Los resultados de la tesis indican que la colofonia y sus derivados son vers√°tiles como aditivos de matrices termopl√°sticas biodegradables y que el proceso de aditivaci√≥n puede llevarse a cabo por m√©todos de procesamiento tanto convencionales como no convencionales. Los hallazgos del estudio son significativos porque la colofonia es un material natural obtenido de fuentes renovables, no es t√≥xica y es biocompatible, de modo que su uso como aditivo no solo mejora las propiedades de los pol√≠meros biodegradables, sino que promueve el estudio y desarrollo de materiales sostenibles lo que contribuye a la disminuci√≥n del impacto ambiental de los pl√°sticos.[CA] L'objectiu general de la present tesi doctoral va ser additivar pol√≠mers biodegradables amb colof√≤nia i els seus derivats mitjan√ßant l'√ļs de t√®cniques de processament convencionals i no convencionals. En aquesta tesi es presenten set treballs dins de quatre blocs d'estudi que van constituir els objectius espec√≠fics de la investigaci√≥. En el primer bloc d'estudi es va realitzar una caracteritzaci√≥ comparativa de cinc colof√≤nies de diferents fonts, per a determinar les seues propietats i establir les difer√®ncies entre cada colof√≤nia per al seu posterior √ļs i aplicaci√≥ com a additius sostenibles de pol√≠mers biodegradables. En el segon bloc d'estudi es additivar colof√≤nia en matrius de pol√≠mers biodegradables, per a aix√≤ es van realitzar dos treballs. En el primer treball es va emprar poli (butilen adipat-co-tereftalat) (PBAT) com a matriu polim√®rica i colof√≤nia (GR) i un pentaeritritol √®ster de colof√≤nia (UT) com a additius. El PBAT es va mesclar amb les resines en diversos continguts i les formulacions es van processar per extrusi√≥ i un posterior emotlament per injecci√≥. En el segon treball es va emprar poli(¬Ņ-caprolactona) (PCL) com a matriu polim√®rica, i com a additius es van emprar GR i cera d'abella (BW). Les formulacions es van preparar per mescla per extrusi√≥ i el processament del material es va dur a terme per una t√®cnica no convencional que √©s la manufactura additiva o impressi√≥ 3D. En el tercer bloc d'estudi es va realitzar l'additivaci√≥ de materials termopl√†stics utilitzant com a base un pol√≠mer biodegradable d'alt rendiment ambiental i com a additiu colof√≤nia i els seus derivats. Com a pol√≠mer base es va emprar mid√≥ termopl√†stic (TPS) i com a additius de van usar els seg√ľents derivats de colof√≤nia: colof√≤nia sense modificar (GR), colof√≤nia deshidrogenada (RD), colof√≤nia modificada amb anhidrido maleic (CM), pentaeritritol √®ster (LF) i √®ster de glicerol de colof√≤nia (UG). La colof√≤nia es va mesclar amb el TPS per extrusi√≥ i el processament de les mescles es va dur a terme per emotlament per injecci√≥. En el quart bloc es va estudiar l'additivaci√≥ de colof√≤nia a matrius polim√®riques mitjan√ßant la t√®cnica d'electrospulveritzaci√≥. Es van realitzar tres treballs en els quals es va optimitzar i va implementar el proc√©s d'electrospulveritzaci√≥ per a la incorporaci√≥ de microesferes de colof√≤nia en matrius polim√®riques. En el primer treball s'avalue l'√ļs d'un proc√©s electrohidrodin√†mic com a m√®tode d'additivaci√≥ de colof√≤nia en matrius polim√®riques i es van obtindre tant microesferes com microfibres de colof√≤nia depenent de la concentraci√≥ de la soluci√≥ inicial. En el segon treball es va optimitzar el proc√©s d'electrospulveritzaci√≥ de colof√≤nia a partir de 24 experiments. Posteriorment, les microesferes de GR es van depositar sobre pel¬∑l√≠cules de per a obtindre sistemes bicapa. Els resultats obtinguts van revelar un gran potencial per a processar f√†cilment sistemes bicapa. Finalment, en el tercer treball es va usar el m√®tode optimitzat d'electrospulveritzaci√≥ per a additivar microesferes de colof√≤nia sobre la capa exterior d'una m√†scara quir√ļrgica a base de polipropil√® (PP), i es va determinar que el revestiment de microesferes va ajudar a mantindre la hidrofobicitat original de la capa exterior de la m√†scara quir√ļrgica. Els resultats de la tesi indiquen que la colof√≤nia i els seus derivats s√≥n vers√†tils com a additius de matrius termopl√†stiques biodegradables i que el proc√©s de d'additivaci√≥ pot dur-se a terme per m√®todes de processament tant convencionals com no convencionals. Les troballes de l'estudi s√≥n significatius perqu√® la colof√≤nia √©s un material natural obtingut de fonts renovables, no √©s t√≤xica i √©s biocompatible, de manera que el seu √ļs com a additiu no sols millora les propietats dels pol√≠mers biodegradables, sin√≥ que promou l'estudi i desenvolupament de materials sostenibles el que contribueix a la disminuci√≥ de l'impacte ambiental dels pl√†stics[EN] The general objective of this doctoral thesis was to add biodegradable polymers with gum rosin and its derivatives, using conventional and unconventional processing techniques. This thesis presents seven works within four study blocks that constitute the specific objectives of the research. The first study block conducts a comparative characterization of five gum rosins from different sources to determine their properties and establish the differences between each rosin for their subsequent use and application as sustainable additives for biodegradable polymers. The second study block examines the compounding of biodegradable polymer matrices with gum rosin, for which two works were developed. The first work uses poly (butylene adipate-co-terephthalate) (PBAT) as the polymeric matrix and rosin (GR) and a rosin pentaerythritol ester (UT) as additives. PBAT was mixed with the resins in various contents, and the formulations were processed by extrusion and subsequent injection molding. The second work uses poly(¬Ņ-caprolactone) (PCL) as a polymeric matrix and GR and beeswax (BW) as additives. The three materials mentioned are biocompatible and biodegradable. The formulations were mixed by extrusion, and the material was processed by an unconventional technique: additive manufacturing or 3D printing. The third study block compounded thermoplastic materials using a biodegradable polymer with high environmental performance as a base and gum rosin and its derivatives as additives. This study used thermoplastic starch (TPS) as the base polymer and the following gum rosin derivatives were used as additives: unmodified rosin (GR), dehydrogenated rosin (RD), rosin modified with maleic anhydride (CM), pentaerythritol ester (LF) and ester of rosin glycerol (UG). Gum rosin and TPS were mixed by extrusion and processed by injection molding. The fourth study block studies the addition of rosin to polymeric matrices using the electrospraying technique. Three works were carried out to optimize and implement the electrospraying process for adding rosin microspheres in polymeric matrices. The first work evaluated the use of an electrohydrodynamic process to add gum rosin to polymeric matrices. The process allowed gum rosin microspheres and microfibers depending on the concentration of the initial solution. The second work optimized the gum rosin electrospraying process from 24 experiments. Subsequently, GR microspheres were deposited on compression molded PCL films to obtain bilayer systems. The results revealed a great potential to efficiently process bilayer systems with high interest in sustainable agricultural, packaging, and/or biomedical applications. Finally, the third work used the optimized electrospraying method to add gum rosin microspheres to the outer layer of polypropylene (PP)-based surgical mask. The results showed that the microsphere coating helped maintain the original hydrophobicity of the outer layer of the surgical mask. The thesis results indicate that gum rosin and its derivatives are versatile as additives in biodegradable thermoplastic matrices and that both conventional and unconventional processing methods can carry out the additive process. The study findings are significant because rosin is a natural material obtained from renewable sources; it is non-toxic and biocompatible. Therefore, using gum rosin as an additive not only improves the properties of biodegradable polymers but also promotes the study and development of sustainable materials, which contributes to reducing the environmental impact of plastics.Gracias a la Conselleria de Innovaci√≥n, Universidades, Ciencia y Sociedad Digital, por la beca otorgada (GRISOLIAP/2019/113), que me ha permitido dedicarme completamente a la realizaci√≥n de este proyecto. A la Conselleria de Innovaci√≥n, Universidades, Ciencia y Sociedad Digital por la ayuda para ‚ÄúSubvenciones para estancias de contratados predoctorales en centros de investigaci√≥n fuera de la Comunitat Valenciana (BEFPI)‚ÄĚ (CIBEFP/2021/30)Pav√≥n Vargas, CP. (2022). Aditivaci√≥n de materiales biodegradables mediante el uso de derivados de colofonia [Tesis doctoral]. Universitat Polit√®cnica de Val√®ncia. https://doi.org/10.4995/Thesis/10251/19138
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