Green . — On Vegetable Ferments . 91 
found a similar body in the petals of Robinia pseudacacia 
associated with another enzyme having diastatic powers. It 
has been shown by Kjeldahl 1 and by J. O’Sullivan 2 to be 
present in the embryo of germinated barley, particularly in 
the rootlets, from which however it is by no means easy to 
extract it. J. O’Sullivan finds it also in the plumule. Sachs 
suggests its existence also in the wintering beet-root and the 
fruiting spikes of Zea Mats. Wassezug 3 has found it in 
certain fungi of the genus Fusarum , which have the power of 
growing in cane-sugar solutions, causing in them formation of 
glucose. When the fungus is cultivated in bouillon made 
from veal, he says it excretes a little of the enzyme into the 
liquid at the period when it forms its conidia. Fernbach has 
extracted it from Aspergillus niger 4 . 
It is not confined to the vegetable kingdom, occurring also 
in parts of the mammalian alimentary canal. 
Various methods for its preparation have been given by 
different authors. Berthelot obtained it in solution in i860, 
and Hoppe-Seyler 5 prepared it from yeast in the form of a 
soluble powder in 1871. He killed the yeast with ether, 
extracted it with water and precipitated the invertase by 
alcohol. Other authors have modified the process in their 
experiments, but their methods are based upon Hoppe- 
Seyler’s. Gunning 6 extracted it from washed yeast by means 
of glycerine. O’Sullivan and Tompson 7 obtained it in 
quantity by pressing good sound yeast for several weeks till 
it liquefied, and then filtering off the liquor from the residue. 
This filtrate contained all the invertase of the yeast, amount- 
ing to from 2 to 6 per cent, of the dry solid matter of the 
latter. From this filtrate they separated the enzyme by adding 
alcohol to 47 per cent., when it was precipitated. To purify 
it they washed it with spirit of the same strength, again ex- 
1 Resume du Compte rendu des travaux du Laboratoire de Carlsberg, 1881. 
2 Transactions of the Laboratory Club, No. 5, vol. III. 
3 Ann. de l’lnstitut Pasteur, 1, p. 525, 1887. 
4 Ibid, 1889, p. 473. 
5 N. Rep. Pharm. 20, 764. 6 Ber. 5, 821. 
7 Journ. Chem. Soc., Oct. 1890, p. 834. 
