BIOTECHNOLOGICAL INVESTIGATION FOR THE PREVENTION OF BIOFOULING .1. BIOLOGICAL AND BIOCHEMICAL PRINCIPLES FOR THE PREVENTION OF BIOFOULING

The most important biological and biochemical methods with potential f or the prevention of biofouling are described. Among these methods, th e isolation of biogenic agents produced by several species of micro- a nd macroalgae and marine invertebrates with antibacterial, antialgal, antiprotozoan and antimacrofouling properties may be the most promisin g and effective method for the prevention of biofouling. The isolated substances with the most potent antifoulant activity are fatty acids, terpenes, terpenoids, lipoproteins, glycolipids, phenols, lactons, pep tides and steroids. The advantage of the utilization of micro- and mac roalgae for the isolation of biogenic agents is that algae can be cult ivated in a short time in mass culture, independent of season. Further more, they can be manipulated to a large extent in the direction of th e 'production of biogenic agents'. However, the cultivation of micro- and macroalgae is very expensive. Marine invertebrates must be collect ed in certain seasons. This collection of marine invertebrates could l ead to an uncontrolled exploitation of marine organisms and to a chang e in the balance of marine ecosystems. Therefore, determination of the chemical structure and the subsequent synthesis of the determined bio genic agents is necessary if marine invertebrates are to be used as pr oducers of biogenic agents. Antifouling systems must be both environme ntally safe and effective for at least 3 yr when formulated as antifou ling paints. There have been a few attempts at this, but no applicable successes have been reported to date.