DEVELOPMENT OF CHEMICAL-SUBSTANCES REGULATING BIOFILM FORMATION

The chemical substances which regulate biofilm formation were examined , and a bioassay system which uses marine bacteria with adhering prope rties was developed. This bioassay system is suitable for screening cr ude extracts from marine organisms. Using this system, those substance s which regulate biofilm formation were isolated from marine organisms . For example, bis(deacetyl)solenolide D was obtained from the marine sponge Psammaplysilla; purpurea. Novel nitroalkanes were also isolated from the Okinawan sponge Callyspongia sp. Ethyl N-(2-phenylethyl)carb amate isolated from the marine bacteria SCRC3P79 (Cytophaga sp.) inhib ited biofilm formation. Furthermore; the N,N-dichloro, isocyanide, iso thiocyanate, and dithiocarbamate derivatives of 2-(4-nitrophenyl)ethyl amine, significantly inhibited the growth of marine attaching bacteria . Interestingly, most of the marine sponges examined contained anti-bi ofilm compounds, such as benzoic acid, aeroplysinin-I, and bromoagelif erin.