What is "solanina"

Solanine \Sol"a*nine\, n. [L. solanum nightshade.] (Chem.) A poisonous alkaloid glucoside extracted from the berries of common nightshade ( Solanum nigrum), and of bittersweet, and from potato sprouts, as a white crystalline substance having an acrid, burning taste; -- called also solonia, and solanina.