Nalin Dora You can use either sequential extraction of compounds using hexane, ethyl acetate and ethanol/Methanol or Direct extraction of crude extract using 80-90% Ethanol or Methanol.

The method of extraction could be :

Pressurized Liquid Extraction: has high yield, extracts both polar and non-polar antifouling compounds effectively. It requires the equipment and if not possible there are other methods:

Cold Maceration for Posidonia oceanica. it is suitable for heat-sensitive antifouling compounds

Ultrasound-Assisted Extraction for the invasive microalgae, since it helps break rigid polysaccharide-rich cell walls and releases antifouling secondary metabolites efficiently.

Choose the apt method and the solvent system based on the metabolites in the samples.

All the best.