ANTIBIOTICS OF ACTINOMYCETES 225 



aureus at dilution of 1/50 million; the pigmented component, at dilu- 

 tion of 1/300,000. 



Toxicity: No data. 



Utilization: None. 



Reference: Brockmann, H., and Bauer, K., Naturwiss., 2, 1950, 492^493; 

 Brockmann, H., and Borchers, I., Chem. Ber., 86, 1953, 261-269. 



Rimocidin 



Produced by: Streptomyces rimosus. 



Method of extraction: Extraction of the mycelium with n-butanol. 



Chemical and physical properties: Amphoteric substance. Analysis: C, 



57.6 per cent; H, 7.8 per cent; N, 1.8 per cent; S, 2.0 per cent. [a]l 5 = 



+75.2°; m.p. 151°C (decomposition). Maximum ultraviolet absorption 



at 279, 291, 304, and 318 m M . 

 Biological activity: Active in concentration of 3 mcg/ml against Candida 



albicans, Histoplasma capsulatum, and many other pathogenic fungi. 



C. neoformans is more resistant. 

 Toxicity: LD 6 o (mice), intravenous, 30 mg/kg. 

 Utilization: Not known yet, if any. 

 Reference: Davisson, J. W., Tanner, F. W. Jr., Finlay, A. C, and Solomons, 



I. A., Antibiotics & Chemotherapy, 1, 1951, 289-290. 



Roseomycin 



Produced by: Streptomyces roseochromogenus. 



Method of extraction: Same as streptomycin and streptothricin. 



Chemical and physical properties: Basic substance similar to streptothricin 



and streptomycin. 

 Biological activity: Active against gram-positive bacteria, gram-negative 



bacteria, and mycobacteria. Very little activity against Clostridia. 



Active against Vibrio comma. Active in vivo against Eberthella typhosa. 

 Toxicity: LD (mice), intravenous and intramuscular, about 1000 mg/kg. 

 Utilization: Not known yet. 

 Reference: Ishida, N., J. Antibiotics (Japan), 3, 1950, 839-853; Nagao, I., 



ibid., C 8, 1950, 20-33; 4, 1951, 24-28. 



Rotaventin 



Produced by: Streptomyces reticuli. 



Method of extraction: Extraction of mycelium with methanol. Concentration 

 in vacuo. Precipitation at pH 2.0. Precipitate washed with ether. 

 Residue dissolved in methanol and precipitated with water. The final 

 purification is accomplished by countercurrent distribution. 



