135 
/ 
Senter ( 400 ) isolated from the blood a catalase of remarkable activity, 
which he called “hernase, ” and which was without action upon guaia- 
cum even in the presence of hydrogen peroxide. More recently L. 
Liebermann ( 269 ) has shown that an aqueous extract of the mesenteric 
fat of the hog and rabbit decomposes hydrogen peroxide energetically, 
without being able to oxidize guaiacum. According to Xeumann- 
Wender( 449 ) yeast, by heating to 45° to 50° C., loses its power to 
induce alcoholic fermentation, whereas the yeast catalase is only 
destroyed at 68° to 70° C. He also showed that yeast in which the 
maltase has been destroyed still retained its catalytic power. L. and 
P. Liebermann ( 27 °) have also shown that the catalase of malt is 
destroyed by heating extract of malt to 80° .C., or by shaking it with 
mercuric oxide and magnesia, whereas the solution can still exhibit 
the guaiacum reaction, especially if oil of turpentine be added. 
Hence they conclude that only the peroxidase is concerned in the 
oxidation of the guaiacum. Pure hemoglobin is powerless to effect the 
decomposition of hydrogen peroxide, and yet it acts as a powerful 
oxygen carrier in a mixture of hydrogen peroxide and guaiacum. 
The general drift of modern opinion seems to be, therefore, that the 
catalases and peroxidases are distinctly different ferments. 
So far as its occurrence is concerned, catalase seems to be one of 
the most widel} T distributed of any of the enzymes. Thus from his 
own observations Loew ( 278 ) arrived at the conclusion that there does 
not exist a group of organisms, or any organ, or even a single vegetable 
or animal cell, that does not contain some catalase. 
According to Loew( 278 ), vegetable catalase exists in two forms, 
one insoluble and the other soluble in water. These he designated 
“a-” and “ /5-cat alase,” respectively. According to him, a-catalase 
is probably a compound of /5-catalase with a nucleo-proteid, while 
the /5-catalase is an albumose, and can be liberated from the insoluble 
form (a-catalase) by means of a dilute alkali. He found that cured 
tobacco, contains but little soluble catalase (/5-catalase), whereas 
well-sweated tobacco contains a great deal. Water alone dissolves 
only traces of a-catalase, while the prolonged action of water at 
moderately high temperatures gradually splits off /5-catalase, espe- 
cially if a small amount of sodium carbonate be added. Whether the 
vegetable catalases obtained from different sources are identical in 
composition and nature, and whether they are identical with the 
animal catalases, is as yet unknown. By most observers the cata- 
lases are regarded as enzymes. They may be obtained in perfectly 
clear solution; thus Senter ( 40 °) found that the catalase of blood passes 
through the Berkefeld filter. They are destroyed by heat; Loew ( 278 ) 
found that vegetable catalase is destroyed at 80° C.; according to 
Senter ( 40 °), hemase is destroyed at 65° C.; Neumann Wender ( 449 ) 
