Polygodial is a sesquiterpene dialdehyde isolated from the leaves of certain peppers and related plants. Noted for its broad antifungal properties, polygodial is also cytotoxic against bacteria, algae, and sea squirts. In mammals, polygodial produces a pungent flavor, activates the transient receptor potential cation channel TRPA1 (EC50 = 59 nM), and produces antinociception.