[Studies to investigate the ecological importance of the mass development of Hydrodictyon reticulatum in infiltration basins for drinking water. III. Identification of the active components by the use of spectroscopic methods and gas chromatography (author's transl)].

Antibacterial substances from H. reticulatum, that was harvested from its natural habitat or grown under culture conditions, could be isolated by extraction with ethanol or by steam destillation from cells as well as from culture filtrate. The active substances were tested by gas chromatography, infrared spectroscopy and mass spectrometry and characterized as a fraction of saturated fatty acids. Its composition seems to depend on external circumstances or culture conditions, respectively, because it differed from experiment to experiment even in samples, harvested at the same day. The most effective acids, active, however, only against grampositive strains are the long chain unsaturated ones with 16 or 18 C-atoms, as shown by bioassay detection (Fig. 3). The C16 = 3-acid was only found in the strain LB236-1b.