188 A MANUAL OF THE PENICILLIA 



su7n, and applied to it the name spinulosin. The substance was subse- 

 quently identified from Aspergillus fumigatus and later synthesized by 

 the same investigators (1938b and c). Raistrick in the same year reviewed 

 the production by molds of spinulosin and other quinones, including 

 fumigatin, a metabolic product of Aspergillus fumigatus Fres. Evaluat- 

 ing the possible antibiotic activity of spinulosin, Oxford (1942b) and 

 Oxford and Raistrick (1942) found it to have relatively low antibacterial 

 activity, inhibiting Gram-positive and gram-negative forms only at dilu- 

 tions of 1:20,000. It is of no particular interest as a possible therapeutic 

 agent. 



Hetherington and Raistrick (1931) reported a yellow coloring matter to 

 be produced from glucose by various species of Citromyces, including C. 

 glaber and C. pfefferianus (regarded as probably Penicillium frequentans 

 and P. spinulosum, respectively). The pigment was designated citromy- 

 cetin (C14H10O7) and its detailed characterization published. It is almost 

 insoluble in cold water, slightly soluble in hot water, somewhat soluble 

 in acetone, fairly soluble in cold absolute alcohol and in hot glacial acetic 

 acid, and readily soluble in aqueous NaoCOs and NaHCOs with the evolu- 

 tion of CO2. It can be crystallized from 50 percent aqueous ethanol as 

 lemon yellow needles containing two molecules of water of crystallization. 



Kroeker, Strong, and Peterson (1935) investigated the lipids of Peni- 

 cillium aurantio-hr unneimi (regarded as P. frequentans in this Manual) 

 and found them to consist essentially of glycerides of palmitic, stearic, 

 oleic, and linoleic acids. Ergosterol was isolated from the non-saponifi- 

 able matter. 



The capacity to produce citric acid appears to be fairly common to 

 members of the Penicillium frequentans series, although in no case are 

 yields known to equal those obtained with selected strains of Aspergillus 

 niger. The production of citric acid by molds which are now recognized 

 as belonging to this series was first reported by Wehmer in 1893. He 

 created a new genus, Citromyces, and described two new species, C. glaber 

 and C. pfefferianus, to incude the responsible strains. His patents taken 

 out in Germany (1894), France (1893), Britain (1893), and the United 

 States (1894), were based upon their use. While positive confirmation is 

 impossible, a sufficient continuity of correspondence and observations 

 exists to support the belief that Wehmer 's species approximated P. fre- 

 quentans Westling and P. spinulosum Thom as we now know them. Maze 

 and Perrier (1904) investigated citric acid production in Citromyces and 

 described four new species as follows: C. citricus, C. tartricus, C. oxalicus, 

 and C. lacticus. 



Butkewitsch (1925) investigated conditions favoring the formation of 

 gluconic and citric acids by Citromyces glaber and Penicillium glaucum, 



