Buffer extracts from five species of marine green algae (Codium sp.) were examined for fibrinolytic and protease activities using a fibrin plate method and chromogenic assay, respectively. Extracts of Codium fragile, C. divaricatum, C. pugniformis, and C. intricatum, contained both activities. From the extract of C. intricatum, which showed the highest activity in both assays, two fibrinolytic enzymes, named CIP-I and CIP-II, were purified to homogeneity by gel filtration followed by ion-exhange chromatography. The two enzymes (M-r, c. 20 k) hydrolyzed fibrinogen with preference to the A alpha chain over B beta or gamma chains. Protease activities peaked between pH 8 and 9, and were completely inhibited by diisopropyl fluorophosphate (DFP), identifying them as serine proteases. (C) 1998 Elsevier Science Inc.