On Vegetable Ferments* 
BY 
J. R. GREEN, M.A., B.Sc., F.L.S., 
Professor of Botany to the Pharmaceutical Society of Great Britain. 
D URING recent years so many investigators have been 
occupied with the study of the several enzymes existing 
in various plants, and so many papers have appeared in 
different scientific journals, that it seems desirable to collect 
together the more important results that have been obtained 
and to present them in something like a consecutive form. 
This is the more needful, as the recent enormous develop- 
ment of bacteriology has led to the isolation of many enzymes 
from the so-called organised ferments, thereby opening to 
discussion the reality or necessity of the division hitherto held 
to exist between the latter and the enzymes themselves. 
In the present paper the writer proposes to give some 
account of the various vegetable enzymes now known to 
exist ; to review their general properties, mode of action, and 
composition, and to discuss briefly their relation to the other 
group. 
Provisionally these bodies may be classified according to 
the materials on which they work. We may thus make four 
well-marked groups, excluding those which are obtainable 
from micro-organisms as well as one or two whose action 
has not been thoroughly investigated. These groups will be — 
(1) Those which attack carbohydrates. These will include 
the different varieties of diastase, the ferment transforming 
inulin, the invertase which breaks up cane-sugar, the cyto- 
hydrolysts attacking cellulose, and the ferment which forms 
vegetable jelly from pectic substances. 
[Annals of Botany, Vol. VII. No. XXV. March, 1893.] 
