Title PRIMJENA NISKOTEMPERATURNIH EUTEKTIČKIH OTAPALA U EKSTRAKCIJI BIOAKTIVNIH KOMPONENTI IZ BILJNOG MATERIJALA UZ PROCJENU ANTIRADIKALNE I ANTIBAKTERIJSKE AKTIVNOSTI : doktorski rad
Title (english) APPLICATION OF DEEP EUTECTIC SOLVENTS IN THE EXTRACTION OF PLANT BIOACTIVE COMPONENTS WITH THE ASSESSMENT OF ANTIRADICAL AND ANTIBACTERIAL ACTIVITY : doctoral thesis
Author Martina Jakovljević Kovač
Mentor Maja Molnar (mentor)
Committee member Ani Radonić (predsjednik povjerenstva)
Committee member Ante Prkić (član povjerenstva)
Committee member Dajana Gašo-Sokač (član povjerenstva)
Granter University of Split Faculty of Chemistry and Technology (Division of Chemistry) Split
Defense date and country 2024, Croatia
Scientific / art field, discipline and subdiscipline NATURAL SCIENCES Chemistry
Universal decimal classification (UDC ) 54 - Chemistry. Crystallography. Mineralogy
Abstract SAŽETAK U okviru doktorskog rada ekstrahirane su bioaktivne komponente (fenolne kiseline, flavonoidi, diterpeni, kanabinoidi i kumarini) iz različitog biljnog materijala primjenom hidrofilnih i hidrofobnih niskotemperaturnih eutektičkih otapala. Pripremljenim otapalima ispitana je viskoznost, polarnost i pH. Probir otapala proveden je ekstrakcijom miješanjem i zagrijavanjem, a optimiranje uvjeta ekstrakcije provedeno je za svaku komponentu za ekstrakciju miješanjem i zagrijavanjem, ekstrakciju potpomognutu ultrazvukom i mehanoekstrakciju. Za optimizaciju je odabrano najpogodnije otapalo, a praćen je utjecaj temperature, vremena, udjela vode i brzine kretanja kuglica. Dobiveni rezultati su uspoređeni sa rezultatima dobivenima konvencionalnim otapalima. Za dobivene ekstrakte pri optimalnim uvjetima ispitana je mogućnost izolacije bioaktivnih komponenti primjenom makroporoznih smola, kao i antiradikalna i antibakterijska aktivnost. Pripremljena niskotemperaturna eutektička otapala i makroporozne smole su reciklirane i korištene ponovno za ekstrakciju i izolaciju. Ekstraktima s najvećim udjelom bioaktivnih komponenti pripremljenima s niskotemperaturnim eutektičkim otapalima i konvencionalnim otapalima određena je stabilnost pri četiri različite temperature skladištenja kroz tri mjeseca. Primjenom hidrofilnih i hidrofobnih niskotemperaturnih eutektičkih otapala učinkovito su ekstrahirane komponente iz grupe spojeva kao što su diterpeni, flavonoidi, fenolne kiseline, tenini, kanabinoidi i kumarini. Korištenim otapalima određena je viskoznost, polarnost i pH pri čemu je pokazana najveća korelacija između viskoznosti i udjela komponenti u ekstraktima. Sve korištene tehnike ekstrakcije su se pokazale kao učinkovite, s vrlo malim razlikama u udjelima komponenti u ekstraktu. Ispitani uvjeti ekstrakcije su pokazali različit utjecaj ovisno o komponenti, što govori u prilog selektivnosti ovog načina ekstrakcije. Praćenjem stabilnosti ekstrakata sa najvećim udjelom bioaktivnih komponenti kroz tri mjeseca uočava se pozitivno djelovanje niskotemperaturnih eutektičkih otapala na većinu bioaktivnih komponenti, posebice pri sobnoj temperaturi. Izolacija bioaktivnih komponenti iz ekstrakata dobivenima niskotemperaturnim eutektičkim otapalima pomoću različitih makroporoznih smola se pokazuje kao učinkovit proces sa visokom adsorpcijskim i desorpcijskim prinosima. Fizikalno-kemijska svojstva makroporoznih smola, kao i adsorpcijsko i desorpcijsko vrijeme te volumen desorbensa kao ispitani parametri pokazuju različit utjecaj ovisno o bioaktivnoj komponenti što ponovno pokazuje da se ovaj proces može koristiti selektivno. Osim za izolaciju bioaktivnih komponenti, makroporozne smole su korištene i za recikliranje niskotemperaturnih eutektičkih otapala, a samim procesom desorpcije reciklirane su i makroporozne smole. Korištenjem istog otapala i makroporozne smole u tri ciklusa pokazano je da je učinkovitost otapala u ekstrakciji i makroporozne smole u adsorpciji i desorpciji za većinu bioaktivnih komponenti iznad 60 %. Osim u slučaju ekstrakta vrkute, ekstrakti dobiveni niskotemperaturnim eutektičkim otapalima pokazuju bolju antibakterijsku aktivnost u odnosu na ekstrakte dobivene konvencionalnim otapalima, pri čemu uzorci tretirani makroporoznim smolama pokazuju još bolju aktivnost u odnosu na početni ekstrakt. S druge strane, ekstrakt kadulje i koprive te uzorci nakon tretiranja makroporoznim smolama pokazuju bolju antiradikalnu aktivnost u odnosu na ekstrakte dobivene konvencionalnim otapalima, dok je antiradikalna aktivnost bolja za ekstrakte dobivene konvencionalnim otapalima za industrijsku konoplju i lavandu. Korištenjem niskotemperaturnih eutektičkih otapala u ekstrakciji umjesto organskih otapala smanjuje se negativan utjecaj na okoliš, povećava selektivnost, a kombinacija s inovativnim tehnikama ekstrakcije dovodi do smanjenja utroška energije i vremena.
Abstract (english) SUMMARY In this doctoral thesis, bioactive components (phenolic acids, flavonoids, diterpenes, cannabinoids and coumarins) were extracted from different plant material using hydrophilic and hydrophobic deep eutectic solvents. For prepared solvents for viscosity, polarity and pH were determined. Solvent screening was performed by stirring and heating extraction, and optimization of the extraction conditions was carried out for each component for stirring and heating extraction, ultrasound-assisted extraction and mechanochemical extraction. The most suitable solvent was chosen for optimization, and the influence of temperature, time, water content, and beads speed was monitored. The obtained results were compared to results obtained with conventional solvents. For the extracts obtained under optimal conditions, the possibility of isolating bioactive components using macroporous resin, as well as antiradical and antibacterial activity, was tested. The prepared deep eutectic solvents and macroporous resins were recycled and used again for extraction and isolation. The stability of extracts with the highest amount of bioactive components prepared with deep eutectic solvents and conventional solvents was determined at four different storage temperatures for three months. Using hydrophilic and hydrophobic deep eutectic solvents effectively extracts components from the group of compounds such as diterpenes, flavonoids, phenolic acids, tannins, cannabinoids and coumarins. Viscosity, polarity and pH were determined with the solvents used, and the highest correlation between viscosity and the amount of components in the extracts was shown. All the extraction techniques used proved to be effective, with very little differences in the amount of the components in the extract. The tested extraction conditions showed a different influence depending on the component, which points to the selectivity of this method of extraction. By monitoring the stability of the extracts with the highest amount of bioactive components for three months, a positive effect of deep eutectic solvents on the majority of bioactive components is observed, especially at room temperature. Isolation of bioactive components from extracts obtained with deep eutectic solvents using different macroporous resins is shown to be an efficient process with high adsorption and desorption yields. The physicochemical properties of macroporous resins, as well as the adsorption and desorption time and the volume of the desorbent as tested parameters show a different influence depending on the bioactive component, which again shows that this process can be used selectively. In addition to the isolation of bioactive components, macroporous resins were also used for recycling deep eutectic solvents, and macroporous resins were also recycled through the desorption process itself. Using the same solvent and macroporous resin in three cycles showed that the efficiency of the solvent in extraction and macroporous resin in adsorption and desorption for most bioactive components is above 60 %. Except in the case of lady mantle extract, extracts obtained with deep eutectic solvents show better antibacterial activity compared to extracts obtained with conventional solvents, while samples treated with macroporous resins show even better activity compared to the initial extract. On the other hand, sage and nettle extract and samples after treatment with macroporous resins show better antiradical activity compared to extracts obtained with conventional solvents, while antiradical activity is better for extracts obtained with conventional solvents for industrial hemp and lavender. Using deep eutectic solvents in extraction instead of organic solvents reduces the negative impact on the environment, increases selectivity, and the combination with innovative extraction techniques leads to a reduction in energy and time consumption.
Keywords
niskotemperaturna eutektička otapala
bioaktivne komponente
ekstrakcija potpomognuta ultrazvukom
mehanoekstrakcija
makroporozne smole
stabilnost
optimizacija
Keywords (english)
deep temperature eutectic solvents
bioactive components
ultrasound-assisted extraction
mechanoextraction
macroporous resins
stability
optimization
Language croatian
URN:NBN urn:nbn:hr:167:911847
Promotion 2024
Project Number: UIP-2017-05-6593 Title: Zelene tehnologije u sintezi heterocikličkih spojeva Title: Green Technologies in Synthesis of Heterocyclic Compounds Acronym: GREENNESS Leader: Maja Molnar Jurisdiction: Croatia Funder: Hrvatska zaklada za znanost
Study programme Title: Chemistry of Mediteranean Cultures Study programme type: university Study level: postgraduate Academic / professional title: doktor/doktorica znanosti, područje prirodnih znanosti, polje kemija (doktor/doktorica znanosti, područje prirodnih znanosti, polje kemija)
Type of resource Text
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Access conditions Open access
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Created on 2024-07-23 11:27:55