PRODUCTION OF ANTITUMOR SUBSTANCE

PURPOSE:To obtain an antitumor substance, by adding penicillin or a related substance to a cultivation filtrate of a bacterium of the genus Streptococcus. CONSTITUTION:A bacterium belonging to the genus Streptococcus, e.g. Streptococcus pyogenes ATCC21060, is cultivated aerobically at 6.0-8.0pH and 30-40 deg.C to separate the resultant microbial cells. Penicillin or a related substance (e.g. in 10-500units/ml, preferably 100 units/ml cultivation filtrate for penicillin G) is added to the resultant cultivation filtrate or a treated filtrate to give the aimed antitumor substance, e.g. physiologically active substance SPE-1 having the following properties; Elementary analysis; C, 41.26-36.64%; H, 4.91-4.10%; N, 6.52-5.40%. Molecular weight; 500-7,000. Decomposition point; Browned at 170 deg.C and blackened at 200 deg.C. Specific rotatory power; [alpha]D =+63.3-64.3 deg.(C= 1.04). Soluble in water and insoluble in methanol, etc. white powder, etc.