Cucurbitin is an

amino acid Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha a ...

and a

carboxy In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl group () attached to an R-group. The general formula of a carboxylic acid is or , with R referring to the alkyl, alkenyl, aryl, or other group. Carboxylic ...

pyrrolidine that is found in ''

Cucurbita ''Cucurbita'' (Latin for gourd) is a genus of herbaceous fruits in the gourd family, Cucurbitaceae (also known as ''cucurbits'' or ''cucurbi''), native to the Andes and Mesoamerica. Five edible species are grown and consumed for their flesh and ...

'' seeds. Cucurbitin causes degenerative changes in the reproductive organs of parasitic flatworms called flukes.Annual Reports in Medicinal Chemistry
Cornelius Kennedy Cain, 1966, Academic Press,

References

Amino acids Pyrrolidines Plant toxins {{heterocyclic-stub