Submitted to: Journal of Natural Products
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/6/2004
Publication Date: 11/19/2004
Citation: Diers, J.A., Pennaka, H.K., Peng, J., Bowling, J.J., Duke, S.O., Hamann, M.T. 2004. Structural activity relationship studies of zebra mussel antifouling and antimicrobial agents from verongid sponges. Journal of Natural Products. 67(12):2117-2120. Interpretive Summary: Antifouling products that are environmentally benign are needed. A natural compound from a marine sponge was found to prevent adhesion of zebra mussels to a substrate at low concentrations. This compound was not toxic to plants, fungi, or human cells at concentrations that were effective against the zebra mussel as an antifouling agent.
Technical Abstract: Several dibromotyramine derivatives including moloka'iamine were selected as potential zebra mussel (Dreissena polymorpha) antifoulants due to the noteworthy absense of fouling observed on sponges of the Order Verongida. Sponges of the Order Verongida consistently produce these types of bromotyrosine-derived secondary metabolites. Previously reported antifouling data for the barnacle Balanus amphitrite supports the results reported here that the comopund moloka'iamine may be a potential zebra mussel antifoulant compound (EC50 = 10.36 uM). The absence of any phytotoxic activity toward aquatic plants and the compounds significant and selective activity against many cancer cell lines futher supports the potential utility of these compounds as a naturally derived antifoulant lead. Moloka'iamine is cytotoxic to P-388, A-549, HT-29 and CV-1 cell lines, but is not active as an antifungal or immunomodulator agent. The use of natural dibromotyramine derivatives from Verongida sponges as environmentally benign antifouling alternatives to metal-based paints and preservatives is important, not only as a potential control of fouling organisms, but also to highlight the ecological importance of these and similar biochemical defenses.