spongine

Spongine is a name that has appeared in the chemical literature as a label for certain secondary metabolites isolated from marine sponges. Unlike a fixed chemical entity, spongine has been applied to more than one compound over time, and contemporary sources rarely treat it as a single, defined structure. Because of this history, modern reviews generally describe spongine as a provisional or historical designation rather than a catalogued compound with a single molecular formula.

Historically, sponges have been a rich source of bioactive small molecules, including alkaloids, terpenoids, and polyketides. In some older reports, compounds referred to as spongine were reported to have biological activities such as cytotoxicity or antimicrobial effects, but the structural assignments in those studies were often incomplete or later revised. As a result, reported activities of spongine are not consistently reproducible and cannot be taken as definitive without unambiguous structure confirmation.

Spongin, by contrast, is a protein-based fibrous component that forms the sponge's skeleton; it is unrelated to small-molecule spongines and represents a different class of biological material.

If you are researching spongine, consult primary literature for the specific sponge species, isolation methods, and the exact structure associated with the term in that publication, as later work may reclassify or rename the compound.