Eterična olja in njihova antioksidativnost

diplomsko delo univerzitetnega študijskega programa I. stopnje

Petra Gjura (Author), Mojca Škerget (Mentor), Petra Kotnik (Co-mentor)

Abstract

Namen diplomske naloge je pridobitev ekstraktov iz kumine, kopra in listov zelene mete pri optimalnih ekstrakcijskih pogojih, kjer je vsebnost karvona in limonena najvišja. Uporabljeni materiali v raziskavah so mleta semena kumine in kopra ter mleti posušeni listi zelene mete. Uporabili smo več različnih tehnik ekstrakcije aromatičnih olj in biološko aktivnih komponent iz rastlinskih materialov za uporabo, tako konvencionalne kot superkritične ekstrakcije. Izvedli smo Soxhlet in ultrazvočno ekstrakcijo. Kot topilo pri Soxhletu smo uporabili 100 % metanol. Eterična olja smo izolirali s konvencionSlno metodo destilacije z vodno paro po Clevengerju, z visokotlačnimi ekstrakcijami s superkritičnimi fluidi (CO2) v laboratorijskem merilu. Dobljenim ekstraktom smo določili antioksidativne lastnosti z uporabo standardnih metod. Antioksidativno učinkovitost ekstraktov smo določevali z uporabo DPPH testa in jo prikazali kot % inhibicije, pri čemer smo merili absorbanco raztopine vzorca in referenčne raztopine. Najvišji % inhibicije je pokazal ekstrakt mete, dobljen s Soxhlet ali ultrazvočno ekstrakcijo. Uporabili smo še β-karotensko metodo, kjer smo merili absorbanco raztopine vzorca, referenčne raztopine in kontrolnega vzorca ter rezultate podali kot % antioksidativne aktivnosti. Diplomsko delo prikazuje študijo povezave med eteričnim oljem, njegovimi komponentami in njihovimi antioksidativnimi učinki. Ekstrakte smo kvalitativno in kvantitativno ovrednotili na vsebnost komponent v ekstraktu (eteričnem olju), s poudarkom na vsebnosti karvona in limonena. Sestavo eteričnih olj ter karvona in limonena smo identificirali s pomočjo ustreznih standardov substanc in jih kvantitativno ovrednotili z metodo eksternega standarda s plinsko kromatografijo, sklopljeno z masno spektrometrijo. Rezultati sestave kažejo na višjo vsebnost D-Limonena in α-Terpineola v meti, D-Limonena in D-Carvona v kumini in D-Limonena, D-Carvona in Apiola v kopru. Za določevanje vsebnosti hlapnih komponent v ekstraktih je bila uporabljena gravimetrična metoda, določili pa smo tudi vsebnosti totanih fenolov v ekstraktih. Koncentracije vsebnosti skupnih fenolov smo podali v miligramih galne kisline na gram ekstrakta ter na gram materiala. Določili smo povezavo med eteričnim oljem in njegovimi komponentami ter antioksidativnimi učinki, ki blagodejno vplivajo na življenje ljudi.

Keywords

antioksidativne aktivnosti;meta;kumina;koper;eterična olja;ekstrakcija;totalni fenoli;diplomske naloge;

Data

Language:	Slovenian
Year of publishing:	2017
Typology:	2.11 - Undergraduate Thesis
Organization:	UM FKKT - Faculty of Chemistry and Chemical Engineering
Publisher:	[P. Gjura]
UDC:	665.5:665.7.038.5(043.2)
COBISS:	20412182
Views:	1993
Downloads:	424
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	Essential oils and their antioxidant properties
Secondary abstract:	The purpose of this study was to obtain extracts from cumin, dill and spearmint leaves at the optimal extraction conditions, where the content of carvone and limonene is the highest. Materials used in the research were ground cumin seeds, dill and ground dried leaves of spearmint. We used several different techniques for extracting aromatic oils and biologically active components of plant materials, i. e. conventional and supercritical extraction. We performed Soxhlet and ultrasonic extraction. As a solvent in the Soxhlet we used 100 % methanol. Essential oils have been isolated by the conventional method of steam distillation acording to Clevenger and by the high-pressure extraction with super-critical fluids (CO2) in a laboratory scale. We used standard methods for determinating antioxidant properties of obtained extracts. The antioxidant effectiveness of the extracts was determined using the DPPH test and presented as percentage of inhibition based on the absorbance of the sample and reference solution. The maximum percent of inhibition showed mint extract obtained by Soxhlet or ultrasonic extraction. We also used β-carotene method where we measured the absorbance of the sample solution, the reference solution and the control sample were measured. The results are presented as percent of antioxidant activity. The thesis shows the study of the links between the essential oil, its components, and their antioxidant effects. The extracts were qualitatively and quantitatively evaluated based on the content of components in the extract (essential oil), with a focus on the content of carvone and limonene. Composition of the essential oils, carvone and limonene were identified by using the appropriate standard substances and quantified by external standard method using gas chromatography coupled with mass spectrometry. The results show higher content of D-limonene and α-terpineol in mint, D-Limonene and D-Carvone in caraway and D-Limonene, D-Carvone and Apiol in Koper. For determining the content of volatile components in the extracts, the relative gravimetric method was used. We also determined the content of total phenols in the extracts, expressed as the extraction yields in %. Concentrations of total phenolics content are expressed per gram of extract and per gram of material. We determined the link between essential oil, its components, and their antioxidant effects, which have a beneficial effect on people's lives.
Secondary keywords:	antioxid antactivicy;mint;cumin;koper;essential oils;extraction;a total phenols;
URN:	URN:SI:UM:
Type (COBISS):	Bachelor thesis/paper
Thesis comment:	Univ. v Mariboru, Fak. za kemijo in kemijsko tehnologijo
Pages:	XII, 86 str.
ID:	9576753