TV.—Tue Amy.oryric action or Diastase or MALrt, AS MODIFIED 
BY VARIOUS CONDITIONS; STUDIED QUANTITATIVELY. By R. H. 
CHITTENDEN AND Gro. W. Cummins, Pu.B. 
Tue close relationship existing between the diastase of malt and 
the amylolytic ferment of saliva has led us to make a careful study 
of the conditions favorable to the action of the former, in the hope 
of obtaining confirmation of previous results obtained with the sali- 
vary ferment.* The widespread use, moreover, of malt extracts as 
therapeutic agents lends to the work in question a practical interest, 
which in no wise detracts from its value. 
Falkt+ has recorded that the diastase of malt loses its amylolytic 
power under the influence of dilute acid, similar to the ferment of 
saliva; that it is made inactive by gastric juice and that the retard- 
ing influence of a dilute acid (say 0°0135 per cent.) on its amylolytic 
power is diminished by the presence of peptone, owing to the proba- 
ble formation of a peptone-acid: compound. Falk, moreover, states 
that the retarding action of hydrochloric acid is due to destruction 
of the ferment, since on neutralization of the acid, amylolytic power 
is not restored. Kjeldahlf{ has recorded that dilute acids in very 
small quantity retard the amylolytic action of diastase; if, however, 
smaller, minimum quantities of acid are added the amylolytic power 
of diastase is increased. The same investigator§ has also noticed 
a like accelerating action of very small quantities of acid on invertin. 
Basnitz|| has found that the presence of carbonic acid invariably in- 
creases the amylolytic power of diastase. Detmer{{ has recorded the 
same fact and in addition, that small quantities of citric acid as well 
as of phosphoric and hydrochloric acid increase the diastatic power 
of malt. Larger quantities of these acids render the malt extract in- 
active. Detmer has also found that the presence of a very slight 
alkaline reaction diminishes the amylolytic power of the ferment. 
Brown and Heron** state that a malt extract neutralized with barium 
hydroxide has its amylolytic power somewhat weakened; thus im- 
* Chittenden and Smith, Trans. Conn, Acad., vol. vi, p. 343. 
+ Virchow’s Archiv, vol. Ixxxiv, p. 119. 
+ Jahresbericht fiir Thierchemie, 1879, p. 382. 
§ Jahresbericht fiir Thierchemie, 1881, p. 449. 
|| Berichte der deutsch chem. Gesell., vol. xi, p. 1443. 
§] Zeitschrift fir physiol. chemie, vol. vii, p. 2. 
** Liebig’s Annalen der Chemie, vol. excix, pp. 236-238. 
SS Te eee 
