Optimisation of phenolic compounds isolation from hawthorn flowers and leaves (Crataegi folium cum flore)

Svrha ovog istraživanja bila je odrediti optimalne uvjete konvencionalnog postupka ekstrakcije fenolnih spojeva iz biljne mješavine cvijeta i lista gloga (Crataegi folium cum flore), vrstu i udio alkohola u otapalu te temperaturu i vrijeme ekstrakcije. Ekstrakti gloga su dobiveni konvencionalnom ekstrakcijom uz refluks primjenom 30, 50 i 70 %-tnih vodenih otopina etanola i metanola. Ekstrakcija je provedena pri temperaturama od 50, 65 i 80 °C u trajanju od 30, 45 i 60 minuta. U ekstraktima su određivani ukupni fenoli, ukupni flavonoidi, ukupne hidroksicimetne kiseline i ukupni flavonoli. Fenolni spojevi pridonose antioksidacijskoj aktivnosti pa je u ekstraktima određivan antioksidacijski kapacitet DPPH i FRAP metodama. Na temelju dobivenih rezultata, utvrđeno je da je najbolja ekstrakcija, odnosno najveći prinosi fenolnih spojeva postignuta uz primjenu 70 % etanola, te pri temperaturi od 80 °C. Istovremeno, vrijeme ekstrakcije nije značajno utjecalo na prinos fenolnih spojeva.The aim of this study was to determine optimal conditions of the conventional extraction process of phenolic compounds from hawthorn leaf and flower herbal mixture (Crataegi folium cum flore), type and alcohol content in solvent, extraction temperature and time. Hawthorn extracts were produced by conventional reflux extraction using 30, 50 and 70 % agueous methanol and ethanol. The extraction process is carried out at temperatures of 50, 65 and 80 °C for 30, 45 and 60 minutes. Total phenolic, total flavonoid, total hydroxicinnamic acid and total flavonol content were determined in extracts. Phenolic compounds contribute to antioxidant activity, so antioxidant capacity by DPPH and FRAP methods was determined. Based on the results, it was found that the best extraction (the highest yields of phenolic compounds) was achieved with the use of 70 % ethanol and at the temperature of 80 °C. At the same time, the extraction time did not significantly affect the yield of phenolic compounds