XVI International Botanical Congess

Seaweed extracts have been tested for algicidal activity against growth of the red tide microalga Cochlodinium polykrikoides. The red tide bloom is in an escalating and worrisome trend in the incidence of mass mortalities of farmed fish and shellfish. Powder of the seaweed Corallina pilulifera, the most potent species, showed algicidal activity against several red tide microalgae, especially C. polykrikoides, Gymnodinium mikimotoi, G. sanguineum, Heterosigma akashiwo, Prorocentrum triestinum, and Pyraminonas sp. Different products of the seaweed C. pilulifera, methanol extract, water extract, powder, and dry tissue inhibited the cell growth. They showed stable algicidal activity not changed by boiling, light, acidic and alkaline treatments.Yong-Ki HongPukyong National University, Department of BiotechnologyNamku, Pusan 608-737, Korea