INHIBITION OF FERTILIZIN AGGLUTINATION AND FERTILIZATION IN ARBACIA BY FUCUS EXTRACTS

Abstract

1. Extracts of the brown alga Fucus vesiculosus inhibit fertilization and the fertilizin agglutination of Arbacia sperm. 2. The inhibition of fertilizin agglutination apparently results from an action on sperm. Sperm washed from the extracts do not agglutinate. Furthermore, fertilizin is not irreversibly inactivated by Fucus extracts. The color and inhibitory properties of Fucus extracts are removed from solution by absorption with sperm. 3. Sperm motility and O₂ consumption were stimulated by Fucus extracts. 4. The inhibition of fertilization is the result of an irreversible action on eggs. The fertilizing capacity of sperm, however, is not destroyed by exposure to inhibitory amounts of Fucus extract. 5. Tannic acid showed inhibitory properties similar to the Fucus extracts. It inhibited fertilization by an irreversible effect on eggs and prevented fertilizin agglutination by an effect on sperm. Tannic acid-treated sperm were capable of fertilizing eggs.