Antifouling activities of N-substituted imides: antimicrobial activities and inhibition of Mytilus edulis phenoloxidase.

In the search for novel biodegradable antifouling agents, a series of imides (N-substituted maleimides and succinimides) have been synthesized. A large majority of N-substituted maleimides and succinimides showed an antimicrobial activity toward gram-positive and gram-negative bacteria and fungi of marine origin with minimal inhibition concentrations in the range of 6 to 24 microg/ml. The imides with an alkyl substituent showed higher activities than aromatic analogues, but structure-activity relationships were not clearly established.

Seasonal variation of antifouling activities of marine algae from the Brittany coast (France).

The antifouling activity of extracts (aqueous, ethanol, and dichloromethane) of 9 marine macroalgae against bacteria, fungi, diatoms, macroalgal spores, mussel phenoloxidase activity, and barnacle cypris larvae has been investigated in relation to season in bimonthly samples from the Bay of Concarneau (France). Of the extracts tested, 48.2% were active against at least one of the fouling organisms, and of these extracts, 31.