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 for the prevention of biofouling are described. Among these methods, the isolation of biogenic agents produced by several species of micro- and macroalgae and marine invertebrates with antibacterial, antialgal, antiprotozoan and antimacrofouling properties may be the most promising 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, peptides and steroids. The advantage of the utilization of micro- and macroalgae for the isolation of biogenic agents is that algae can be cultivated in a short time in mass culture, independent of season. Furthermore, they can be manipulated to a large extent in the direction of the 'production of biogenic agents'. However, the cultivation of micro- and macroalgae is very expensive. Marine invertebrates must be collected in certain seasons. This collection of marine invertebrates could lead to an uncontrolled exploitation of marine organisms and to a change in the balance of marine ecosystems. Therefore, determination of the chemical structure and the subsequent synthesis of the determined biogenic agents is necessary if marine invertebrates are to be used as producers of biogenic agents. Antifouling systems must be both environmentally safe and effective for at least 3 yr when formulated as antifouling paints. There have been a few attempts at this, but no applicable successes have been reported to date.