Isolation of a spermatozoid-releasing and -attracting substance from female gametophytes of Laminaria digitata.

SEVERAL dioecious marine brown algae have been valuable in studying chemical communication during sexual reproduction. For example, female gametes of Ectocarpus siliculosus, Cutleria multifida and Fucus serratus secrete olefinic hydrocarbons into the seawater to attract male gametes(1-3). A more complex system is found in the order Laminariales, which includes the large kelps. Mature female gametophytes in members of this group secrete highly volatile material with spermatozoid-attracting activity, which also induces explosive discharge of antheridia(4). We report here a study of this volatile material. It is now possible to attribute spermatozoid-releasing and -attracting activity to one specific compound.