32 
and closely associated with this remarkable group of substances are 
the peroxidases and catalases, which have the power of decomposing 
hydrogen peroxide or rendering active the oxygen which it contains. 
While in many instances, as pointed out by Wender C 448 ), the precise 
role of these catalysts in the life of the cell has not as yet been deter- 
mined, it is known that they are very widely distributed in the plant 
and animal kingdoms and that they are concerned in many important 
bio-chemical processes. Thus, according to Tolomei ( 423 ) and Mar- 
tinand ( 286 ) the oxidation of the coloring matter of the grape and the 
production of those aromatic substances which confer upon old wine 
its delightful aroma and taste is due to the action of oxidases which 
are present in the grape and in the yeast. Aso ( 15 ) has shown that 
oxidases are concerned in the curing of tea. They probably also play 
a part in the curing of tobacco, and in the change of color of anv vege- 
table tissue from green to brown, which results finally in the produc- 
tion of humus substances. According to Griiss ( 201 ), the oxidases play 
an important role in the formation of starch grains. Hahn ( 204 ) found 
an oxidase in Arum macuiatum which had the power of oxidizing 
grape sugar and which apparently assists in intramolecular respiration, 
and Raciborski ( 337 ) is of the opinion that the vegetable oxidases play 
the same role in the vasculiferous plants as that played by hemoglobin 
in the higher animals and hemocyanin in the lower animals, viz, that 
of the oxygen-laden vehicle of respiration. Woods ( 462 ) has shown 
that oxidases are responsible for the etiolation of green leaves. 
Palladin ( 317a ) and also Miss Wheldale ( 449a ) are of the opinion that 
anthocyanin, the red pigment of certain flowers, results from the 
action of an oxidase on some colorless, chromogenic substance con- 
tained in the flower. 
The oxidases are by no means confined to the plant, but are found 
in many animal tissues, where they are assumed to play an equally < 
important role in oxygen metabolism. Thus, Dubois ( 147 ) attributes the 
phosphorescence of phosphorescent animals and plants to the action 
of an oxidase to which he has given the poetic name of “ Luciferase,” 
and this same observer ( 148 ) has traced the formation of a purple dye 
by the mollusc Murex brandaris, to the action of an oxidase which he 
calls “Purpurase.” Carnot ( m ) found that the saliva and other secre- 
tions contain certain oxidases. Portier ( 33 °) has pointed out that 
oxidases are concentrated in the epidermal and exposed structures of 
Steudel ( 4n ); Zur chemischen Erkenntnis biologischer Oxydationsreaktionen, by 
Engler and Herzog ( 163 ); Contribution a l’Etude des Applications Therapeutiques des 
Oxydases et des Metaux Ferments, by Pierre See( 398 ); Die Bedeutung der Katalyse 
fiir die Medicin, by H. Schade( 360 )| Les Oxidations de l’Organisme, by Enriquez and 
Sicard ( 166 ); Ueber die Oxydationsfermente der Leber, by Jacoby ( 224 ); Die Oxydasen, 
by Neumann Wender ( 448 ) ; The Properties and Classification of the Oxidizing Enzymes, 
and Analogies between Enzymic Activity and the Effects of Immune Bodies and 
Complements, by Moore and Whitley ( 306 ) ; Les Ferments Oxydants, by Chodat ( 116 )/ 
