1972; Percival et al., 1980) had shown the existence of differences between the polysaccharides exudated by different diatom species (Table 1). For example, the extracellular
1972; Percival et al., 1980) had shown the existence ofdifferences between the polysaccharides exudated by differentdiatom species (Table 1). For example, the extracellular