14 DYNAMICS OF LIVING MATTER 



I think Jacquet * was the first to separate a "ferment of oxidation " 

 from the living organism, and to obtain it in a watery extract from 

 tissues. The oxygen of the air oxidizes benzylalcohol (CeHjCH OH) 

 only slowly to benzoic acid (CeHjCOOH) at body temperature; the 



OTT 



same is true for the oxidation of sahcylaldehyde CeH^Ap-Trto salicylic 



OH i-'Uxl 



acid CsH^p^p^TT- Schmiedeberg had already shown that the animal 



tissues accompHsh this oxidation comparatively rapidly. Jacquet 

 proved that this energetic oxidation of benzylalcohol is not dependent 

 upon Hving protoplasm, as he found that it occurred also in dead tissues. 

 Tissues poisoned with carbolic acid continue to accelerate these oxida- 

 tions, and even tissues which have been preserved in alcohol are capable 

 of so doing. Nor are these oxidations dependent upon the structure 

 of the cells, as watery extract frdin the cells also had oxidative effects 

 upon benzylalcohol. The action of the oxidizing enzymes is annihi- 

 lated when they are heated to a temperature of about ioo° — pos- 

 sibly through a hydrolysis of the enzyme itself. 



Engler and Wild f have found that there exists a group of substances 

 which behave like Traube's autoxidizable substances. These sub- 

 stances have the peculiarity of easily forming peroxides of the following 



These peroxides are capable of giving off one atom of oxygen to dis- 

 oxidizable substances. Through the loss of this atom of oxygen the 

 peroxides are transformed into oxides. This view is supported by an 

 important observation which was first made by van't Hoff and Jorissen. 

 If the quantity of oxygen which disappears in the oxidation of a known 

 quantity of a disoxidizable substance is measured, it is found to be in 

 most cases exactly twice as large as the quantity required for the oxida- 

 tion of the disoxidizable substance. J This finds its explanation in the 

 fact that for every molecule of oxygen which is taken up by the autoxi- 

 dizable substance, only one atom is transferred to the disoxidizable 

 substance. 



The view of Engler and Wild is also supported by the investigations 

 of Kastle and Loevenhart§ on the oxidizing effects of plant tissues, 

 e.g. the potato, and their watery extracts. They found that organic 



* ]3.c(i-aet. Arch, fiir experimentelle Pathologie und Pharmakologie, Vol. 29, p. 386, 1892. 

 t Engler und Wild, Ber. der deutsch. chem. Geselkch., Vol. 30, p. 1669, 1897. Engler und 

 Weissberg, Kritische Studien iiber die Vorgange der Autoxydation, Braunschweig, 1904. 

 } See also Manchot, Zeitsch.fUr anorganische Chemie, Vol. 27, p. 420, 1901. 

 § Kastle and Loevenhart, Am. Chem. Journal, Vol. 26, 1901. 



