Characterization of Anemopsis californica essential oil–β-cyclodextrin inclusion complex as antioxidant prolonged-release system

Antioxidant activity is a property of Anemopsis californica essential oil (ACO). However, ACO possesses volatile compounds that provide strong flavors and that are susceptible to degradation, complicating its application. An alternative is its encapsulation in a β-cyclodextrin (β-CD) matrix. Therefore, the characterization of β-CD–ACO inclusion complexes as an antioxidant prolonged-release system was the objective of this work. The ACO yield was 8.26 mg/g of dry sample. Elemicin (EL) (68.9%) and methyleugenol (ME) (11.7%) comprised the majority compounds identified by gas chromatography (GC). The β-CD–ACO inclusion complex, with a 90:10 ratio based on the precipitation technique, exhibited best percentage of recovery, greater ACO retention, and major antioxidant capacity determined by DPPH [2,2-diphenyl-1-picrylhydrazyl] and ABTS [2,2′-azino-bis-(3 ethylbenzothiazoline-6-sulfonic acid)] assays. Antioxidant activity was maintained during encapsulation. Free β-CD and β-CD:ACO presented the hysteresis phenomenon according to water sorption isotherms. A prolonged-release system was studied using different relative humidities (0, 33, 66, 96 and 100%). EL demonstrated 93.75% of release in highest relative humidity, while ME released completely. These results suggest application of the β-CD–ACO complex in systems in which it can be passively released and in controlled form, as in active food or drug packaging.