A novel pyrrolizine alkaloid, 5-(furan-3-carbonyl)-2,3-dihydro-1H-pyrrolizine-7-carboxylic acid, was isolated from the peels of Punica granatum. Its structure was elucidated on the basis of 1D- and 2D-NMR and HR-ESI-MS spectra and then confirmed by X-ray diffraction. It represents a new type of natural pyrrolizine alkaloid, named, punicagranine (1). 1 showed inhibition of nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 cells. To our knowledge, the pyrrolizine alkaloid skeleton was reported in natural products for the first time. © 2019 Elsevier Ltd