INFLUENCE OF PROCESS PARAMETERS ON THE EXTRACTION OF POLYPHENOLS FROM OLIVE TREE LEAVES (Olea Europaea L) WITH SUBCRITICAL WATER
| Autor: | Grušovnik, Mateja |
|---|---|
| Přispěvatelé: | Škerget, Mojca |
| Jazyk: | slovinština |
| Rok vydání: | 2012 |
| Předmět: |
konvencionalna ekstrakcija
total phenols celokupni flavonoidi antioksidativna aktivnost listi oljke antioxidant activity olive tree leaves udc:547.9.056:543.544(043.2) tannins total flavonoids subcritical water extraction celokupni fenoli ekstrakcija s subkritično vodo conventional extraction tanini |
| Zdroj: | Maribor |
| Popis: | V diplomskem delu smo z metodama konvencionalne ekstrakcije in ekstrakcije s subkritično vodo pripravili ekstrakte iz listov oljke. Pri samem eksperimentalnem delu smo se pri konvencionalni metodi ekstrakcije omejili samo na določena topila: vodo ter vodni raztopini etanola in acetona. Ekstrakcije s subkritično vodo pa smo izvajali pri različnih procesnih pogojih: temperaturi, času in tlaku. Določali smo koncentracije celokupnih fenolov, celokupnih flavonoidov in taninov v ekstraktih. Koncentracije fenolnih spojin smo podali na gram ekstrakta ter na gram materiala. Antioksidativno učinkovitost ekstraktov pa smo določevali po metodi DPPH. Razen tega smo določili tudi optimalne procesne pogoje za ekstrakcijo z obema metodama. Ugotovili smo, da je ekstrakcija s subkritično vodo veliko bolj učinkovita metoda od konvencionalnih metod. Ta metoda ekstrakcije nam daje primerljive ali celo boljše rezultate kot konvencionalni postopki, hkrati pa ohranja značilnosti antioksidantov v ekstraktih in omogoča selektivno ekstrakcijo določenih komponent pri določenih procesnih pogojih. In the diploma work extracts from olive tree leaves were prepared by using conventional extraction methods and subcritical water extraction. In the experiments with conventional extraction method following solvents were used: water and aqueous solutions of ethanol and acetone. The subcritical water extraction was performed at different process conditions: temperature, time and pressure. Concentrations of total phenols, total flavonoids and tannins in the extracts were determined. Concentrations of phenolic compounds were expressed in grams per gram of extract and per gram of material. The antioxidant activity of the extracts was determined by using the DPPH method. In addition, the optimal process conditions for the extraction with both methods were determined. It was found that subcritical water extraction is more effective method than the conventional methods. This extraction method gives comparable or even better results than conventional procedures, while maintaining the characteristics of the antioxidants in the extracts and allows selective extraction of certain components at specific process conditions. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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