1 1 6 Green. — On Vegetable Ferments. 
Muntz’s suggestion that the embryo acts as a ferment is not 
borne out by the facts. Neither the cotyledons nor the axis 
of the embryo contains any enzyme, the latter being present in 
the cells of the endosperm only. Its distribution is not limited 
as is that of the ferments in the germinating barley-grain, but 
extends throughout the whole endosperm, the part nearest 
the cotyledons not being at first more attacked than the rest, 
though the absorption of the reserve materials by the embryo 
begins there and leads to the gradual destruction of the 
endosperm from that side. 
In the resting seed of Ricinus this ferment exists in the 
condition of a zymogen ; which can be transformed into the 
active enzyme by the action of weak acids at 45 0 C. for about 
three hours, or by the prolonged action of water at the ordinary 
temperature. 
The ferment, like so many of the others described, is found 
to be very sensitive to changes in the reaction of the medium 
in which it is working. It is most active in a neutral medium, 
is hindered by -o 66 per cent., and stopped by *133 per cent. 
HC 1 . With alkalis the hindering effect is not so marked, *c6 6 
per cent, of Na 2 C 0 3 only retarding it slightly. A little less than 
1 per cent, is quite inhibitory. The ferment is not destroyed 
by the action of these reagents, for on neutralising the solution 
it resumes its activity. It is, however, much more readily 
damaged by acid than alkali, exposure to -133 per cent. HC 1 
for three and a half hours reducing its activity nearly 90 per 
cent., while -66 per cent. Na 2 C 0 3 in the same time only 
lessens its powers one-half. 
The existence of fat-splitting enzymes has since been 
demonstrated by Sigmund 1 in both resting and germinating 
seeds of the Rape, the Opium Poppy, Hemp, Flax, and Maize. 
His mode of experiment was to crush the seeds with water, 
and estimate the free fatty acid in the resulting emulsion 
immediately, and again after allowing it to stand twenty-four 
1 Sigmund, Ueber fettspaltende Fermente im Pflanzenreiche. Sitzungsber. d. k. 
Akad. der Wissensch. Wien, Math.-Nat. Classe, Bd. XCIX, July 1890, and Bd. C, 
July 1891. 
