24 
gen was developed either by the extract or by the residue. In a 
second test, solutions of 0.2 per cent oxalic and sulphurous acids were 
permitted to act for eighteen hours under the same conditions men- 
tioned above. The /-catalase was almost entirely destroyed and the 
a-catalase was also considerably injured. 
The number of cubic centimeters of oxygen developed by a-catalase 
in thirty minutes was as follows: 
ce 
SP oniMol eo deat eats as Eee Se ci eS ee ie Ta ae ee 158 
NV abh O02) percent. Oxalicacid ht tee ae ae ae ee ee 3 
Waith:0:2, per:cent:sulphuroustacide-2. 4.22 BS 2s es eee 28 
A solution of 0.1 per cent acetic acid at the ordinary temperature 
did not injure the catalytic power in one hour, but injured it gradually 
at a temperature of 55° C. 
When sweated tobacco was suspended in fifty times its weight of a 
2 per cent sulphuric acid solution the catalytic power was destroyed in 
fifteen minutes.’ A solution of /-catalase lost its activity in fifteen 
minutes after the addition of 1 per cent sulphuric acid. a@-catalase 
behaves the same, as was shown on suspending tobacco in fifty times 
its weight of 1 per cent sulphuric acid. 
Saturated baryta water kills 4-catalase in two days, but only slowly 
injures a-catalase, as shown” in an experiment with 2 grams cured 
tobacco suspended in twenty-five times its weight of baryta water. 
After neutralization with acetic acid and addition of 5 cc. hydrogen 
peroxid, the amount of oxygen developed in 15 minutes was as follows: 
CC: 
MEAT ANAGC = 232 280d a 2 i pu at a ne nee 
PC malAGG = an Fal Je, 2 ap saith Pe Tees eas) eit eer een eee oa) 
@Gonprol to -catalase 2. 2222 se oS oS cee ee aon ae ee ae 89 
Sodium hydrate in a dilution of 1 per cent kills a- and /-catalase 
almost instantly, while a dilution of 0.1 per cent has no injurious 
influence, at least not within a short time. 
BEHAVIOR TOWARD ALCOHOL. 
Absolute alcohol injures neither a- nor f-catalase at the ordinary 
temperature in twenty hours. One gram of sweated tobacco was 
mixed with 10 ec. absolute alcohol. The alcohol was filtered off 
‘It may here be mentioned that in all such cases the liquid was neutralized with 
dilute caustic soda before the hydrogen peroxid was added. An excess of the dilute 
acid had to be applied, since the tobacco often contains 10 per cent and over of salts 
of organic acids (malic, citric, oxalic acids). 
2 Of course a small part of the dissolved baryta was rendered inactive by combina- 
tion with the acids bound to the ammonia and nicotine contained in the tobacco, 
but this fact, considering the large amount of baryta water, does not essentially alter 
the above inference. 
3 While absolute alcohol does not dissolve a trace of the enzym, alcohol of a strength ~ 
of 50 per cent dissolves a considerable amount. 
