132 INFECTION 



furnished. The same microorganism, when grown on different media 

 or under different conditions, may produce totally different ptomains. 



Ptomains may, however, produce disease, and even death, when they 

 are ingested with food that has undergone bacterial decomposition. In 

 most instances of meat-poisoning, however, which are frequently as- 

 cribed to the presence of ptomains, a specific microorganism, the 

 Bacillus botulinus, or a member of the Bacillus enteritidis group of 

 Gartner, is usually responsible. The commonest sources of ptomain 

 poisoning are improperly preserved meats, fish, sausages, cheese, ice- 

 cream, and milk. This subject received full consideration in Vaughan 

 and Novy's "Cellular Toxins." 



A number of ptomains are known, and of some the exact chemical 

 constitution has been established. Brieger has separated one from 

 decomposing flesh and cholera cultures, called cadaverin, which Laden- 

 burg has shown to be pentamethylendiamin, and prepared synthetical^. 

 Muscarin, isolated by Schmiedberg and Brieger, and tyrotoxicon, iso- 

 lated by Vaughan, are also well known. 



In the isolation of bacterial ptomains Brieger's method is generally 

 employed, which consists of acidulating large amounts of culture with 

 hydrochloric acid, boiling, filtering, evaporating the filtrate to a syrupy 

 consistency, dissolving in 96 per cent, alcohol, and precipitating and 

 purifying by means of an alcoholic solution of mercuric chlorid. 



Besides occurring in food-poisoning, ptomains may be formed as the 

 result of putrefactive processes going on in abscesses, gangrenous areas, 

 and within the gastro-intestinal canal, and enough of these may be 

 absorbed to produce symptoms of intoxication. Under these condi- 

 tions it is possible for bacteria to produce ptomains that may be absorbed 

 and produce symptoms of intoxication without the bacteria themselves 

 actually gaining entrance to the tissues, and therefore not constituting, 

 according to our definition, a true infection. Pernicious anemia, 

 chlorosis, and allied conditions have been ascribed to the absorption of 

 such ptomains from the intestinal canal. Obviously it is difficult or im- 

 possible to always differentiate between bacterial toxins and bacterial 

 ptomains, or the products of protein decomposition dependent upon 

 bacterial activity, and we can but admit the possibility of the produc- 

 tion and absorption of both bacterial toxins and ptomains under certain 

 pathologic conditions. Most ptomains probably are produced as the re- 

 sult of decomposition of the dead protein medium upon which the bacteria 

 grow, and to a lesser extent by the destruction of the bacterial cells them- 



