RESUMEN
Toxin in the form of sodium salt was extracted from lyophilized algal cells by 0.1 M sodium carbonate-sodium bicarbonate at pH of 8.5. The extract was purified from pigments by using n-butanol and freed from high molecular weight impurities by dialysis. Chemically, the toxic substance exhibit a peptide nature. Chromatographic investigation after the extract indicated that the toxin contained ornithine, serine, arginine, threonine, alanine, valine and leucine, and amino acids. An aqueous solution of the dialyzable fraction, after purification, was used to determine the LD50, it was equal to 9.51 mg/kg body weight. Blood samples were taken 24 hours after intraperitoneal and subcutaneous injections in albino rats. Intraperitoneal injection markedly decreased red blood cell count and hemoglobin contents, more than a subcutaneous injection. Such depletion may be related to the destruction of erythrocytes. With both injections the activities of both S-ALT and S-AST enzymes were higher than the control samples