the Ferment of Madder on Sugar. 171 



mentation of asparagine, malic acid, and their compounds, is one 

 of the most interesting facts of organic chemistry. As far as I 

 know, however, its direct formation from sugar has not hitherto 

 been observed, and I consider this as the most important fact 

 revealed by this investigation. In future, should its presence 

 be detected in any part of the vegetable or animal organism, its 

 origin need no longer be a subject for doubtful speculation, as it 

 is now known to be a product of the decomposition of sugar, 

 whether it be cane-sugar, grape-sugar, or sugar of milk*. 



I shall venture, in conclusion, to offer a few remarks on the 

 general nature of the process of fermentation here described, 

 and its relation to other processes of the same kind previously 

 known. 



The highly-interesting and peculiar class of bodies called fer- 

 ments, comprises substances which are all of a very complex 

 nature, and are at the same time not characterized by any marked 

 peculiarities in their appearance, form, or general properties. It 

 is chiefly by their action on other bodies, by the different species 

 of decomposition which they induce in the latter, and by the 

 nature of the products thereby formed, that we are enabled to 

 distinguish the ferments from one another, and arrange them in 

 different classes. Now the effects or species of decomposition 

 produced by ferments are of two kinds — general and specific. 

 The general effects are those produced by all ferments, without 

 distinction, or are common to several classes of ferments. The 

 specific effects are those peculiar to each ferment alone! The 

 general effects are again of different kinds ; some being produced 

 during the first stages of the fermentation, others when the pro- 



* The only indication which I can find of the formation of succinic acid 

 from sugar having previously been observed, is a statement of Beissenhirtz 

 {Berlinisches Jahrbucli der Pharmacie, anno 1818, p. 158), v^^ho allov^^ed a 

 mixture of honey, bread, Slliquu diilcis (the fruit of the Ceratonia siliqua), 

 vinegar, spirits of wine, and water to ferment, neutralized the acid with 

 lime, and then subjected the solution of the lime salt to distillation, together 

 with oxide of manganese and sulphuric acid, when he obtained first a di- 

 stillate of acetic acid, and afterwards a sublimate of succinic acid. Here 

 the Siliqua dulcis probably yielded only the ferment, since John could 

 discover in it no succinic acid ready formed, and the honey the sugar acted 

 on. Pliimacher repeated this experiment, but without success. Piria dis- 

 covered that asparn^ine is formed during the germination of the seeds of 

 various Leguminoscc, such as peas, beans and vetches, and that the aspara- 

 gine, by fermentation, yields succinic acid. Dessaignes could not discover 

 what body contained in the seeds it is, which leads to the formation of 

 asparagine ; but he found that pea flour, when allowed to ferment with 

 caseine, produced considerable quantities of succinic acid. It is now evident 

 that this acid may have been formed directly from the starch of the pea 

 flour, though it is possible (and it would be a fact of uncommon interest if 

 it were discovered to be the case) that the latter passes through the inter- 

 mediate stage of asparagine. 



