Extraction Kinetics and Anethole Content of Fennel (Foeniculum vulgare) and Anise Seed (Pimpinella anisum) Extracts Obtained by Soxhlet, Ultrasound, Percolation, Centrifugation, and Steam Distillation

Abstract
Foeniculum vulgare (fennel) and Pimpinella anisum (anise) extracts were obtained by Soxhlet, cold percolation, ultrasound assisted extraction, and centrifugal extraction using ethanol as solvent; anise extracts were also obtained by steam distillation. Soxhlet presented the highest yields for both fennel and anise seed (16.8% and 23.3%, respectively). The highest anethole content among ethanolic extracts was obtained for centrifugal extraction (6.8 mg/g and 143 mg/g for fennel and anise extracts, respectively). Steam distillation presented low yield (0.26%), but high anethole content (68- 98%, area). Anise ethanolic extracts also tested positive for flavonoids.