20.500.12556/DKUM-94779 Podkritična voda kot zeleno topilo za separacijo vrednih spojih iz plodov gloga (Crataegus ssp.) magistrsko delo študijskega programa II. stopnje Subcritical water as green solvent for separation of valuable compounds from hawthorn fruits (Crataegus ssp.) V zadnjih letih narašča zanimanje za učinkovito izrabo naravnih virov, kot so zdravilne divje rastline in zelišča, ter njihovo pretvorbo v dragocene sestavine. Med njimi izstopajo plodovi gloga (Crataegus spp.), ki zaradi svojih bioaktivnih lastnosti in možnih zdravilnih učinkov veljajo za posebej obetavne. V magistrskem delu smo raziskali postopek separacije vrednih spojin iz gloga (Crataegus spp.) z uporabo podkritične vode. Ocenili smo vpliv različnih procesnih parametrov, kot so temperatura, tlak in čas ekstrakcije, na izkoristek ekstrakcije in sestavo produktov (fenolne spojine, flavonoidi, maščobne kisline, ogljikovi hidrati, antioksidativna aktivnost). Izvedli smo tudi konvencionalno ekstrakcijo z organskimi topili, s katero smo določili vsebnost maščobnih kislin v materialu. Ekstrakcije so bile izvedene pri različnih temperaturah (130 °C, 150 °C, 170 °C in 190 °C), časih ekstrakcije (15, 30 in 60 minut) ter razmerjih med glogom in vodo (1:10 in 1:5). Najvišji izkoristek ekstrakcije (50,14 %) je bil dosežen pri 190 °C, 15 minutah in razmerju 1:10. Pri enakih pogojih sta bili doseženi tudi najvišji vsebnosti totalnih fenolov (57 mg GA/g materiala) in flavonoidov (4,5 mg QU/g materiala). Najvišja vsebnost celokupnih ogljikovih hidratov (220 mg/g materiala) je bila določena pri 170 °C, 60 min in razmerju 1:10. Najvišja antioksidativna aktivnost (33 %) je bila dosežena pri 190 °C, 60 minutah in razmerju 1:5. HPLC analiza je pokazala največje vsebnosti katehina in epikatehina, pri višjih temperaturah pa tudi epigalokatehin galata (EGKG). Prisotni so bili tudi kvercetin, izokvercetin in kavna kislina. Izvedena je bila tudi FTIR spektroskopija mletega materiala in trdnih produktov ekstrakcije. V oljnem ekstraktu, ki smo ga pridobili s konvencionalno ekstrakcijo sta bili najbolj zastopani linolna in oleinska kislina, zaznane pa so bile tudi palmitinska, stearinska in arahidonska kislina. Metoda ekstrakcije z uporabo podkritične vode kot topila tako predstavlja okolju prijaznejši pristop za izolacijo vrednih spojih iz gloga, saj se s tem izognemo uporabi organskih topil, ki so pogosto toksična in zahtevajo dodatne korake pri odstranjevanju. In recent years, there has been a growing interest in the efficient use of natural resources, such as medicinal wild plants and herbs, and their conversion into valuable ingredients. Among these, hawthorn fruits (Crataegus spp.) stand out as particularly promising due to their bioactive properties and potential medicinal effects. In this master thesis, the separation of valuable compounds from hawthorn (Crataegus spp.) using subcritical water was investigated. The influence of different process parameters such as temperature, pressure and extraction time on the extraction yield and the composition of the products (phenolic compounds, flavonoids, fatty acids, carbohydrates, antioxidant activity) was evaluated. A conventional organic solvent extraction was also carried out to determine the fatty acid content of the material. The extractions were carried out at different temperatures (130 °C, 150 °C, 170 °C and 190 °C), extraction times (15, 30 and 60 minutes) and hawthorn/water ratios (1:10 and 1:5). The highest extraction yield (50.14 %) was obtained at 190 °C, 15 minutes and ratio 1:10. The highest content of total phenolics (57 mg GA/g material) and flavonoids (4.5 mg QU/g material) were also obtained at the same conditions. The highest total carbohydrate content (220 mg/g material) was determined at 170 °C, 60 min and ratio 1:10. The highest total carbohydrate content (220 mg/g material) was determined at 170 °C, 60 min and a 1:10 ratio. The highest antioxidant activity (33 %) was obtained at 190 °C, 60 min and a 1:5 ratio. HPLC analysis showed the highest contents of catechin and epicatechin and, at higher temperatures, of epigallocatechin gallate (EGKG). Quercetin, isoquercetin and caffeic acid were also present. FTIR spectroscopy of the ground material and solid extraction products was also performed. In the oil extract obtained by conventional extraction, linoleic and oleic acids were the most abundant, while palmitic, stearic and arachidonic acids were also detected. The extraction method using subcritical water as a solvent thus represents a more environmentally friendly approach to isolate valuable compounds from hawthorn, as it avoids the use of organic solvents, which are often toxic and require additional removal steps. glog podkritična voda separacija bioaktivne spojine biomasa hawthorn subcritical water separation bioactive compounds biomass true true false [I. Rojko] Slovenski jezik Angleški jezik Magistrsko delo/naloga 2025-08-27 09:02:11 2025-09-23 13:11:15 2025-10-30 03:15:18 0000-00-00 00:00:00 2025 0 Maribor 0 Maribor 1 spletni vir (1 datoteka PDF (X, 52 str.)) 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 66.066.083:634.17(043.2) 255291139 MAG_Rojko_Ina_2025.pdf MAG_Rojko_Ina_2025.pdf 1 5C618815FF39AE7B133598F9143EE4EE 9827201dea40ac7632c4812a70112ecacaef75b6a36de23551f52e4bc5712464 6b152b39-9079-11f0-9526-00155d000105 https://dk.um.si/Dokument.php?lang=slv&id=198336 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0