METABOLIC PRODUCTS 291 



nose are the best hexoses; maltose is the best disaccharide ; starch and 

 its degradation product dextrin are good carbon sources. Streptomyces 

 griseus does not utihze nitrate nitrogen. L-ProHne is the most favorable 

 single amino acid, but addition of this amino acid to other sources of 

 nitrogen does not increase yields (see also Thornberry and Anderson, 

 1948). A popular account of the development of streptomycin is to be 

 found in Epstein and Williams (1946). 



Aureomycin. This antibiotic is produced by Streptomyces aureofaciens. 

 Aureomycin has been prepared in pure crystalline form (Duggar, 1948). 

 In addition to being effective against many Gram-positive and Gram- 

 negative bacteria, aureomycin is also active against certain rickettsial 

 and viral agents. Preliminary reports on the use of aureomycin for 

 treating Rocky Mountain spotted fever have been favorable (Schoenbach 

 et al., 1948). Aureomycin appears to be of great clinical value in treating 

 lymphogranuloma venereum and granuloma inguinale, two virus diseases 

 of man (Wright et al, 1948). 



Chloromycetin. This antibiotic was discovered independently in two 

 laboratories (Ehrlich et al., 1947, and Carter et al., 1948). It is produced 

 by Strepto77iyces venezuelae and is the first useful antibiotic to be produced 

 synthetically on a commercial scale. Chloromycetin is active against 

 certain Gram-positive and Gram-negative bacteria, acid-fast bacteria, 

 and Rickettsia (Smith et al., 1948). It has been reported that this anti- 

 biotic has been used successfully to treat epidemic typhus (Payne and 

 Knaudt, 1948). 



Chloromycetin contains non-ionic chlorine and a nitro group, two 

 unusual features in compounds of biological origin. The formula is given 

 below : 



O H NHCOCHClo 



N— <f >^C— C— CH2OH 



O HO H 



Chloromycetin (Chloramphenicol) 



Ergot. Among the alkaloids produced by fungi, only those obtained 

 from the sclerotia of Claviceps purpurea appear to be used in medicine. 

 Seven related alkaloids have been isolated from ergot. These alkaloids 

 have different pharmacological properties. The most useful alkaloid, 

 ergonovine, is isolated from the others before use. Certain undesirable 

 effects of the other alkaloids are avoided by this procedure. Ergonovine, 

 and formerly a mixture of ergot alkaloids, is used to stimulate uterine 

 contraction. At present there is no satisfactory synthetic substitute for 

 ergonovine (Mass, 1950). 



In 1941, 571,000 lb. and in 1944, 85,000 lb. of ergot sclerotia were 

 imported into the United States. If the sclerotia are consumed in large 



