48 Chittenden and Cummins—Amylolytic Action 
1 2 3 a 5 6 
0-1 per cent. HCl 0 0°42 c.c. 0°85 ¢.¢. 4:25.¢c.c¢. 8:5 ec. 16-9b1ene: 
0°5 " Na2.Co; )* 10 cc 9°75 9°5 75 50 0 
01 fy HCl j 16°95 16°55 16°1 12°7 8°45 0 
The six solutions were now exactly alike; neutral to test papers 
and contained the same amounts of diastase and sodium chloride. 
They had, however, been exposed to the action of the above percent- 
ages of sodium carbonate for 1 hour at 40° C. Their amylolytic 
power was now determined in the usual manner (action on 1 gram of 
starch in a total dilution of 100 ¢. c.) with the following results : 
Total amount 
No. Wt. Cuin ¥%. reducing bodies. Starch converted. 
1 01739 gram. 0°3558 gram. 32°02 per cent. 
2 071737 0°3554 31POT 
3 06-1745 0°3570 32°13 
4 0°0341 0°0722 6°49 
5 0'0319 0:0678 6°10 
6 0°0281 0°0602 5°41 
No destructive action is apparent until 0°025 per cent. sodium car- 
bonate is reached; warming the malt extract with 0°005 per cent. 
sodium carbonate causes no destruction whatever, while with 0°025 
per cent. destruction is very great. The amount of malt extract 
(30 c. ¢.) experimented with, being the same as was used in deter- 
mining the influence of alkaline carbonate on the amylolytic power 
of the ferment, the two series of results are directly comparable and 
show plainly that the retarding action of small percentages, in the 
present case up to 0°005 per cent., is due to simple retardation with- 
out destruction of the ferment. Beyond this point, however, as in 
the presence of 0:025 per cent. the greatly diminished amylolytic 
action is due to destruction of the ferment. Hence it would appear 
that in the case of the diastase of malt the destructive action of 
sodium carbonate is out of all proportion to its retarding action. 
This apparent difference, however, between diastase and the ptyaline 
of saliva is due, as we shall show later on, to the comparatively 
small amount of pvroteid matter in the malt extract. Saliva very 
greatly diluted, so that the percentage of proteid matter is reduced 
to a minimum, shows similar results. 
Influence of neutral peptone on the amylolytic action of diastase. 
It was demonstrated some time since,} that the presence of neutral 
peptone tends td increase the amylolytic action of neutral saliva. 
* The two equalizing mixtures were united before being added to the main solutions, 
+ Chittenden and Ely, Amer, Chem, Jour., vol, iv, 107, 
