Abstract
Laurus nobilis essential oil (LEO) was isolated by microwave-assisted hydro-distillation in a yield of 2.7%. The obtained oil from China was analyzed by GC and GC/MS. The main components from the oil were terpinyl acetate (23.14%), followed by terpineol (5.83%), caryophyllene (5.27%), eucalyptol (5.25%), and methyl eugenol (5.25%). Supramolecular micro-capsules of β-cyclodextrin (β-CD), heptakis (2,6-di-methyl)- β-CD (DM-β-CD), mono[2-O-(2-hydroxyethyl)]-β-CD (HE-β-CD), and mono[2-O- (2-hydroxy-propyl)]-β-CD (HP-β-CD) with LEO were prepared and various affecting factors were examined in detail. Furthermore, the formation constants (Ka) and the thermodynamic parameters (ΔG, ΔH and ΔS) were determined in the ranges of 20-50°C. The results indicated that the stoichiometry of the LEO-β-CD supramolecular microcapsules was 1:1 (molar ratio), the Ka decreased with the increase of temperature, and the inclusion abilities were according to following order: β-CD> HE-β-CD > DM-β-CD > HP-β-CD. The antioxidant and DPPH free radical scavenging activity of LEO was higher than those of BHT and PG. But superoxide anion inhibitory activity was weaker than that of PG.