Note
Protein extracts from nine species of green and red marine macroalgae (Chlorophyta and Rhodophyta) were invested for the ability to agglutinate human types A, B, and O, sheep and rabbit erythrocytes. All of the protein extracts agglutinated human and rabbit erythrocytes. In general, human erythrocytes were agglutinated more strongly than sheep and rabbit erythrocytes, but none of the algal extracts were blood group specific.