CHAPTER LVII. 



CHEMICAL ACTIVITY OF THE ASPERGILLACE^E. 

 BY PROF. DR. 0. WEHMER. 



289. General Review. 



THE present chapter deals specially with certain chemical effects 

 of the Aspergillacece, many of the representatives of this family 

 being worthy of note, having formed the subject of numerous 

 investigations in this connection. This has already been discussed 

 in various other parts of the present work, so that all we have 

 to do now is to arrange the facts briefly, for the characterisation 

 of the family in this respect as well. 



The presence of enzymes, as the means of producing effects of 

 decomposition, has been confirmed in all the species examined for 

 this purpose. The number of enzymes identified seems to be still in- 

 creasing, so that nearly all the enzymes known are found associated 

 in Aspergillacece. Instances of the decomposition of carbohydrates 

 (disaccharides and polysaccharides), glucosides, fats and proteids, 

 by invertase, maltase, lactase, amylase, (diastase), inulase, cellulase 

 (cytase), pectinase, melecitase, raffinase, emulsin, lipase, pro- 

 tease, &c., have been noticed ; and mention has also been made 

 of lab enzyme, amidase and tannase, as well as of oxidising and 

 reducing enzymes. Aspergillus niger and the collective species 

 " Penieittium glaucum" have particularly served as the subjects 

 of experiment in these researches ; but similar observations have 

 also been recorded with regard to A. oryzce, A. Wentii, A. glaucus, 

 Penic. luteum, and isolated instances of other species of Aspergillus 

 and Penicillium, as well as in the case of Allescheria Gayoni 

 (Eurotiopsis Gayoni). Unfortunately the value of the results has 

 been considerably impaired by the uncertainty regarding the 

 identity of the so-called " Penicillium glaucum " examined by the 

 different authors. Only in a very few instances have the enzymes 

 in question been actually isolated, their presence having been, 

 as a rule, deduced from the reaction with the culture liquid or 

 with extracts from the triturated growths of mould. 



In addition to enzyme action, true fermentative action in the 

 stricter sense is found in only a few species ; and in only one, 

 namely Allescheria Gayoni, has any decided alcoholic fermentation 

 been observed up to the present. On the other hand, oxidising fer- 



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