A Screening Method for Antifouling Substances Using Spores of the Fouling Macroalga Ulva conglobata Kjellman

Abstract

Fouling macroalgae cause serious problems by settling on ships' hulls, power plant cooling systems, aquaculture systems, and other marine infrastructure. In order to solve this problem, it is necessary to find antifouling substances without toxicity or with lower toxicity than that of toxic agents such as TBTO [bis-(n-tributyltin)-oxide]. For this purpose, an assay for antifouling substances is important. First, the effects of environmental factors on attachment and germination of spores of the fouling macroalga Ulva conglobata were examined. The optimum conditions for attachment and germination of spores were: temperature, 20-25°C; salinity, 33; light intensity, 3000 1x under long-day regimen. Under such conditions, a new and efficient assay method for antifouling substances against the attachment of fouling macroalgae was developed. Antifouling activity was statistically examined.