A simple procedure for the extraction of natural products from fennel seeds is reported. Fennel (Foeniculum vulgare) is an Angiospermae (flowering plant) that belongs to the carrot family. Fennel is native to the Mediterranean region but is now widely cultivated. India is the world’s largest producer of fennel, however significant amounts are also cultivated in Bulgaria and China. Fennel bulbs and seeds are used in cooking and as an herbal medicine. Both the bulb and seeds are aromatic. The isolation of trans-anethole, one of the major aromatic compounds in fennel along with a smaller amount of p-allylanisole (estragole), and other more polar components is described here. The protocol, developed as an experiment for introductory organic chemistry laboratories, provides instruction in natural product isolation, qualitative chemical tests and interpretation of IR and NMR spectral data.
Easterday et al. (2023) studied this question.