Study on ultrasound assisted extraction of oleoresin from star anise fruit (Illicium verum H.) by using ethyl alcohol and ethyl lactate as a solvent

Abstract

This study aimed at investigation on process conditions for extraction of oleoresin from star anise fruits ((Illicium verum H.). The sample was treated with ultrasound under the change of parameters including time (10, 20, 30 min), temperature (30, 40, 50 oC) and ratio of material to solvent (1:6, 1:8, 1:10). Total phenolic content was evaluated to find out the best condition. As the results, the best condition for oleoresin extraction in this study was observed at 30 min, 50 oC for temperature and the ratio 1:10 (m/s). By comparison, the oleoresin yield extracted by ethanol and ethyl lactate solvent were not significant different (22.43% and 22.80%, respectively). Also, the phenolic compound of oleoresin obtained by ethanol and ethyl lactate was approximately equal (309.20 and 321.15 mg GAE/g (d.m.), respectively). Meanwhile, trans-anethole content in oleoresin by using ethyl lactate was higher than compare to ethanol (69.955% and 15.892% (r.m); 60.579% and 13.587% (r.m), respectively). The content of shikimic acid was found in oleoresin by ethyl lactate extraction (8.22% and 1.57% (r.m) be higher than those extracted by ethanol (7.02% and 1.87% (r.m)). The study was implemented to contribute to the investigation of oleoresin extract methods which was highly effective, environmentally friendly, helps to reduce costs, shorten time and make it be easier for producers. In addition, the success of this study was the basis for the continuous research on other plants and medicinal herbs in extraction.