Sixty-nine natural products derived from Phaeophyta (brown algae), Rho
dophyta (red algae), Porifera (sponges), Cnidaria (soft corals), and M
ollusca (nudibranchs) were investigated for their cytotoxic, antimalar
ial, and antimicrobial effects. Fifty-six were found to mediate a posi
tive response in one or more of these test systems.