20.500.12556/DKUM-17121 DOLOČANJE VSEBNOSTI BETULINA IN BETULINSKE KISLINE V LUBJU BREZE OBTAINING CONTAIN OF BETULIN AND BETULINIC ACID FROM BIRCH BARK Eni največjih virov prostih radikalov oz. največjih oksidantov so kisik, kajenje, UV-sevanje in onesnaženost, ki prihaja iz okolja. O antioksidantih je bilo narejenih ogromno raziskav in študij, saj so bistvenega pomena za naše zdravje in vitalnost, imajo zavirajoč vpliv na rakave celice, staranje in bolezni nasploh.(1) Betulin in betulinska kislina iz brezinega lubja nas varujeta pred škodljivimi prostimi radikali, saj sodita med antioksidante oziroma lovilce prostih radikalov.(2) V diplomski nalogi smo izolirali betulin in betulinsko kislino iz lubja breze s superkritično ekstrakcijo s CO2. Poskuse smo opravili pri različnih temperaturah, tlakih in času, da smo ugotovili, pri katerih pogojih je izkoristek najboljši. Najboljši izkoristek smo dobili pri ekstrakciji, ki je potekala 2 uri pri 80°C in tlaku 300 bar. K superkritičnemu CO2 smo dodali tudi kotopili metanol in etanol ter primerjali rezultate. Dobljene produkte smo nato analizirali s HPLC, kjer smo predhodno s standardom betulina in betulinske kisline določili vrednosti na kromatogramih pri valovni dolžini 215 nm in z računalniško integracijo ploščin izračunali maso aktivnih komponent na gram ekstrakta pri različnih pogojih in topilih. Določili smo tudi kinetiko poteka ekstrakcije. Some of the biggest free-floating radicals i.e. biggest oxidants are oxygen, smoking, UV-radiation and pollution coming from environment. Many researches and studies on antioxidants have been made, and they are of a crucial importance to our health and vitality, and have obstructive influence upon cancer cells, aging and deseases in general. Betulin and Betulinic acid from birch-tree bark, the cathcers of free radiccals, protect us from harming free-floating radicals, whic belong to antioxidants. In diploma, betulin and betulin-ic acid from bark were isolated by means of extraction with CO2. Experiments were made at different temperatures, pressures and at different times, to find out the influence of conditions on the extraction yield. The best result was obtained when extraction was performed at 80 °C under 300 bar pressure. Co-solvents methane and ethane were added to supercritical CO2 and results were compared. Resulting products were analysed with HPLC, by means of standards betulin and betulinic acid, for which the chromatograms were measured at 215 nm wave length, and with the help of the computer integration of areas, the weight of active components per g of extract were calculated. Kinetic of extraction process was also determined experimentaly. betulin betulinska kislina ekstrakcija breza superkritični fluid betulin betulinic acid extraction birch supercritical fluid true true false [R. Staniša] Slovenski jezik Angleški jezik Diplomsko delo 2010-12-21 18:14:29 2010-12-23 11:50:08 2022-04-13 09:13:18 2023-12-21 03:34:50 2010 0 Maribor 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 665.5.061(043.2) 15002390 URN:SI:UM:DK:5ZGKZ0NU UNI_Stanisa_Robi_2010.pdf UNI_Stanisa_Robi_2010.pdf 1 D1C21F82F44AE994488159C9F64832A3 3f289d6877a4850e032ffb3b5c0bc29fbd6edd535b6a11ae145241eb0a4b8fff d05ea556-7c04-11eb-bb7a-00155d0001ca 20.500.12556/dkum/a3aca2a8-152e-41aa-9e55-de616b90b19e https://dk.um.si/Dokument.php?lang=slv&id=19791 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0