Estragole (ES) is a natural constituent of a number of plants (e.g. tarragon, sweet basil and sweet fennel) and their essential oils have been widely used in foodstuffs as flavouring agents. Estragole ES was given GRAS Generally Recognized As Safe status by the Flavor and Extract Manufacturer’s Association FEMA, 1965 and is approved by the Food and Drug Administration for food use 21 CFR code of Federal Regulation 121.1164 . Several studies with oral, i.p. or s.c. administration to CD-1 and B6C3F1 mice have shown the carcinogenicity of ES. In vivo and in vitro experimental assays have shown that EST has sedative, anticonvulsant, antioxidant, antimicrobial, and anesthetic activity.

Methylcyclopentenolone (also known as methyl cyclopentenolone), a flavor compound that is used in the standard olfactory acuity test in patients with smell disorders.