Chemical composition and biological activity of essential oil from bitter orange seeds : bachelor thesis

Gorka naranča (Citrus aurantium L.) je biljka iz porodice Rutaceae koja je nastala križanjem pomela (Citrus maxima Merr.) i mandarine (Citrus reticulata Blanco, 1837). Proizvodi eterična ulja u cvijetu, listu, plodu, kori i sjemenkama. Eterično ulje sjemenki gorke naranče izolirano je metodom vodene destilacije u aparaturi po Clevengeru te mu je određen kemijski sastav vezanim sustavom plinska kromatografija – spektrometrija masa (GC-MS). Analizom je dobiveno da je najzastupljeniji spoj limonen (45,5 %) i upravo je on odgovoran za specifičan miris eteričnog ulja. Antioksidacijska aktivnost određena je metodama FRAP i DPPH te je utvrđeno da ispitivano eterično ulje nema značajnu antioksidacijsku aktivnost što se moglo i pretpostaviti s obzirom na njegov kemijski sastav budući da limonen zauzima gotovo polovicu masenog udjela smjese hlapljivih spojeva u eteričnom ulju. Ispitana je i sposobnost inhibicije enzima acetilkolinesteraze metodom po Ellmanu i utvrđeno je da eterično ulje pokazuje jako malu sposobnost inhibicije acetilkolinesteraze. Bitter orange (Citrus aurantium L.) is a plant of the family Rutaceae which was created by crossing pomelo (Citrus maxima Merr.) and mandarin (Citrus reticulata Blanco, 1837). It produces essential oil in a flower, leaf, fruit and seeds. Essential oil of bitter orange seeds was isolated by water distillation in the apparatus according to Clevenger and a chemical composition analysis was performed by gas chromatography - mass spectrometry (GC-MS). The analysis showed that the most common compound is limonene (45.5 %) and it provides a specific smell of essential oil. The antioxidant activity was determined by FRAP and DPPH methods and it was found that essential oil doesn´t have significant antioxidant activity which could be assumed due to its chemical composition since limonene occupies almost half of the mass fraction of the volatile compounds in essential oil. The ability to inhibit acetylcholinesterase was determined by Ellman´s method and it was found that essential oil has very small activity to inhibit acetylcholinesterase.