522 A MANUAL OF THE PENICILLIA 



Penicillium expansum to be enhanced by the accumulation in the substra- 

 tum of by-products of its metabohsm. 



McAlister (1938) investigated the effect of the species on the oxidation- 

 reduction potentials of liquid culture media. 



Datillo-Rubbo (1938) foimd a mold resembling Penicillium expansum 

 rather than P. roqueforti as the dominant species in two Dolce Verdi (a blue- 

 veined type) cheeses. 



Skinner (1934), investigated the synthesis of amino acids from Ca(N03)2 

 by a mold reported as Penicillium flavo-glaucum (see p. 518). All of the es- 

 sential amino acids were produced, but with cystine only in small amounts. 



Kaess (1934) and Kaess and Schwartz (1935) reported Penicillium flavo- 

 glaucum (regarded as P. crustosum of this Manual) as responsible for the 

 spoilage of refrigerated meat and investigated the effect of air motion and 

 humidities. 



Dox and Neidig (1914) reported the production by Penicillium expansum, 

 of a new polysaccharide, mycodextran, 



"penicillium glaucum" and "penicillium crustaceum" 



Use of the designation Penicillium glaucum Link, or simply P. glaucum, 

 to cover green, yellow-green, or blue-green Penicillia not otherwise iden- 

 tified, is all too common in the published literature — especially in papers 

 whose content is chiefly biochemical or physiological in character. Link 

 originally (1809) differentiated P. glaucum from P. expansum, inadequate 

 as the separation was. Later (1924) he grouped the two together and re- 

 ferred to the lot as P. glaucum. Today the latter name is practically 

 meaningless and altogether inadequate for reporting work on any specific 

 strain or type of Penicillium. Penicillium crustaceum, which goes back to 

 Fries (1829) and is today almost equally meaningless, is less commonly but 

 nevertheless often used in the same general and vague sense as P. glaucum. 

 A large literature has grown up around both species. In some papers 

 they are referred to along with few to several other molds. These can be 

 ignored for the most part. In other cases whole papers are centered around 

 tests or experiments conducted with a single Penicillium referred to as P. 

 glaucum or P. crustaceum. Sometimes the source of the strain (or strains) 

 gives a clue to its identity, or in other cases some particular reaction may 

 serve to more or less identify the culture studied. Generally, however, 

 there is no way of knowing which of many different green species might 

 have been under observation. 



The value of this literature is questionable. However, since we do not 

 wish to ignore it completely, we have included in the Topical Bibliography 

 (Chapter XVI) a number of references to papers centering around these 

 two historic species. Reference to them is introduced at this point in the 



