24 INTRODUCTION. 



As above stated, the chemical processes in animals and plants do 

 not stand in opposition to each other; they offer differences indeed, 

 but still they are of the same kind from a qualitative standpoint. PFLU- 

 GER believes that there exists a blood-relation between all living cells 

 of the animal and vegetable kingdoms, and that they originate from the 

 same root. The animal body is a complex of cells, hence study of the 

 chemical processes must not only be made upon higher plants, but also* 

 upon unicellular organisms in order that we get a proper explanation 

 of the chemical processes in the animal organism. Although a bio- 

 chemical study of the micro-organisms is very important, we must bear 

 in mind also the important role played by such organisms in animal 

 life, chiefly as exciters of disease; hence the study of the conditions of 

 life of these micro-organisms and the chemical investigation of the prod- 

 ucts produced by them must be of infinite importance. 



The products produced by micro-organisms may be of very dif- 

 ferent kinds. Among the substances produced in the decomposition 

 of animal fluids and tissues by putrefactive organisms we find those 

 having a basic nature. To this class belong the cadaver alkaloids called 

 ptomaines, first found by SELMI in human cadavers and then specially 

 studied by BRIEGER and GAUTiER. 1 Certain of these are poisonous, 

 designated as toxines, while others are non-poisonous. They all belong 

 to the aliphatic compounds and generally do not contain oxygen. 

 As an example of these basic substances we must mention the two 

 diamines, cadaverine or pentamethylenediamine, C 5 Hi 4 N 2 , and putrescine 

 or tetramethylenediamine, C 4 Hi 2 N2, which have awakened special 

 interest because they occur in the contents of the intestine and in the 

 urine in certain pathological conditions, especially in cholera and cystin- 

 uria. 2 The putrefaction bases marcitine, CgHigNs, putrine, CnHoe^Oa, 

 and viridinine, CgHi 2^0.3 isolated by ACKERMANN, also belong to this 

 group. Of special interest is the bacterial poison isolated by FAUST 3 , 

 called sepsine, CsHu^Ojj, which is the substance producing the char- 

 acteristic toxic action of putrefactive masses. Sepsine was prepared 

 by FAUST as a crystalline sulphate which, on repeated evaporation of 

 its solution, was readily converted into cadaverine sulphate. 



Those substances of basic nature which are incessantly and rec;ularlv 



1 Selmi, Sulle ptomaine od alcaloidi cadaveric! e loro importanza in tossicologia, 

 Bologna, 1878; Ber. d. d. chem. Gesellsch., 11, Correspond, by H. Schiff ; Brieger, 

 Ueber Ptomaine, Parts 1, 2, and 3, Berlin, 1885-1886; A. Gautier, Traite de chimie 

 appliquee a la physiologic, 2, 1873, and Compt. rend., 94. 



2 See Brieger, Berlin, klin. Wochenschr., 1887; Baumann and Udransky, Zeitschr. 

 f. physiol. Chem., 13 and 15: Brieger and Stadthagen, Berlin, klin. Wochenschr., 1889. 



3 Faust, Arch. f. exp. Path. u. Pharm., 51; Ackermann, Zeitschr. f. physiol. chem.,, 

 54 and 57. 



