Atropine is a tropane alkaloid , that can be extracted from the Deadly nightshade ( Atropa belladonna ) , mandrake ( Mandragora officinarum ) and certain other plants . Atropine is a tropane alkaloid extracted from deadly nightshade ( Atropa belladonna ) , jimsonweed ( Datura stramonium ) , mandrake ( Mandragora officinarum ) and other plants of the family Solanaceae .