Vines . — Tryptophane in Proteolysis. n 
the existence of such an enzyme, and it is generally alluded to 
in books relating to the chemistry of brewing under the name 
of 4 peptase,’ a name which should now be altered. 
My own observations enable me to assert that the enzyme 
is undoubtedly present, and that it is remarkably vigorous. 
The experiments were conducted with ‘ green malt ’ ; that is, 
barley which had germinated on the malting-floor for 1 1 days, 
but had not been dried in the kiln. 
An extract was prepared by pounding in a mortar about 200 grms. 
of the barley with 350 cc. of distilled water to which 2 cc. of chloro- 
form had been added ; the thick liquid was set to filter all night in 
a cold room. On the following morning the filtered liquid was found 
to have a slight acid reaction, and to give distinct evidence of the 
presence of tryptophane. 
About 100 cc. of the liquid were placed in each of three bottles 
1, 2, 3: to (1) nothing was added, except 10 drops of 4°/ 0 HCN 
as an antiseptic; to (2), besides 10 drops of HCN, 0-2 cc. HC 1 was 
added ; (3) was neutralized, and to it were added 10 drops of HCN, 
and 0-5 grm. of Na 2 CO s . The three bottles were placed in the 
incubator at 10 a.m. In two hours (1) and (3) gave a somewhat 
stronger tryptophane-reaction, (2) a weak one; 2 hours later, the 
results were much the same. 24 hours later (1) gave a strong reaction, 
(3) a less strong, and (2) still a weak one; it was observed that (3), 
which had been alkaline on the previous day, was now strongly acid, 
and that (1) had become more acid. 
No proteid was added in any of these experiments, the reserve 
proteid of the grain providing the necessary material for digestion 
(auto-digestion). 
From these observations it is clear that the enzyme acts 
strongly in liquid of natural acidity, and that its action is 
diminished and perhaps inhibited by the presence ofo-s°/ o HC 1 . 
With regard to the effect of an alkaline liquid, the result is 
less distinct : but it appears that some digestion occurred during 
the first day when the reaction was alkaline, whilst the 
stronger reaction on the second day may be attributable to 
the fact that the liquid had become acid. 
I then proceeded to ascertain if tryptophane is present in 
kiln-dried pale malt ; and, as might be expected, I found it. 
