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PHYSIOLOGICAL OXIDATION PROCESSES. 873
idases to heat the views are contradictory. Czyhlauz and v. Fiuni
found that the peroxidases from animal tissues were remarkably resistant
to high temperatures, while Batelli and Stern x
find that animal peroxi-
dases arc destroyed even at 66° C.
According to Bach’s theory on the one hand, substances are nec-
essary for the oxidation, which take up oxygen with the formation of
peroxides (oxygenases) and on the other hand, substances which are
able to transport the oxygen from the peroxides to the oxidizable bodies
(peroxidases). In certain oxidations, for example in the phenols, the
peroxidases can be replaced by certain metallic combinations.2
The
iron, of the blood pigments, acts in this way in the guaiacum reaction
(see Chapter XIV). The oil of turpentine here represents the peroxide
and can be replaced by hydrogen peroxide. The oxidizable substance,
which becomes blue in the reaction, is the guaiaconic acid in the guaiac
gum.3
Irrespective of whether the division of the oxidation enzymes into
oxygenases and peroxidases can be carried out in all cases, there are
various oxidation processes, whose occurrence by a combination of oxy-
genase (or peroxide) with peroxidase (or metallic salt) can be explained only
with difficulty. According to Bertrand’s 4
view the action of plant
oxidation enzymes is connected with their manganese content. Never-
theless Bach 5 has been able to prepare enzymes from plants which were
entirely free from iron as well as manganese salts. Starting from Ber-
trand’s view, Trillat 6 has prepared solutions of manganese salts, alkali
and colloidal substances, which acted like oxidizing enzymes. Dony-
Henault 7 has prepared artificial "oxidases" from a faintly alkaline
solution of gum treated with a solution of manganese salt. According to
Euler and Bolin 8 the salts of certain organic acids have the ability of
setting the oxidation power of manganese salts free. Similar observations
have been made by Wolff.9
In the oxidation of auto-oxidizable substances
the presence of extremely small amounts of iron salts may be of advantage,
1
Czyhlarz and v. Ftirth, Hofmeister’s Beitrage, 10, 358 (1907); Batelli and Stern,
Bioch. Zeitschr., 13, 44 (1908).
2
Ber. d. d. chem. Gesellsch., 43, 366 (1910).
3
C. E. Carlson, Zeitschr. f. physiol. Chem., 48, 69 (1906). P. Richter, Arch.
d. Pharm., 244, 90 (1906).
<Compt. Rend., 124, 1032, 1355 (1897).
6
Ber. d. d. ehem. Gesellsch., 43, 364 (1910).
8
Compt. Rend., 138, 274 (1904).
7
Bull. acad. roy. de Belgique, 1908, 105.
8
Zeitschr. f. physiol. Chem., 57, 80 (1908).
9
Ann. inst. Past., 24 (1910).
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