( 1204 ) 
Determination of the influence of acid and alkali on 
fat-splitting by microbic lipase. 
The influence of acid and alkali on fat-splitting by this lipase was 
ascertained as follows. 
Ten experiment tubes were filled with 15 c.c. of a neutral 
thymol-containing culture of lipolytic bacteria, 10 ¢.c. of a 10°/, fat 
emulsion in agar, and into the tubes from 1 to 10 were introduced 
respectively from 2 to 24 drops of a concentrated lactic acid solution 
in water, so that each contained respectively from 1 to 12 ce. 
UT IN acu: 
A second series of tubes treated in the same way, contained 
instead of lactic acid ammonium-carbonate, so that from 1 to 10 they 
contained respectively 1.8 to 18 ecc. '/,, N ammonium-carbonate. 
After 8 hours at 37° C. they were quickly cooled to 7° C. and 
ot For the neutralisation of a 10°/, fat emulsion in agar 0.45 
e.c. '/,, N acid is required. 
The results of these experiments are united in the following tables. 
Influence on fat-splitting by microbie lipase. 
Be | 3 4 VS | 6 
| 
ie Bie P| 
| 
| | | 
PI RERE ae ae ale 25, lo. 95 0. 75 05510: 45) 0.45) 0.05) — i 
1 . | 
c.c. l/o N Lactic acid | 0 1 8 Or 
| 
| | 
after 8 hours at 37° C. | 08/15 5.7.1 5.6 17.5 | 95 ie 
| 
Fat-splitting by Ammoniumearbonate. 
c.c. Yy9 N Amm. carb. |O | 1.8 | 3.6 | 7.2 [10.8 [14.4 |18. 
| | | | 
c.c. 1/j9 N acid used after | 
8 hours at 37° C. | 0.55, O75) 22 L ee De 2 0 
0.4 | | | 
| | 
| 
fatty acid formed. {0 | 0.10] 0.30 0.75, 0.95] 1.30} 1.65 
Injluence of Aimmoniumcarbonate on microbic lipase. 
c.c. 1/49 N acid formed. | 1.25] 1.55) 2.05) 2.95] 3.15) 3.75) 3.90 
| | 
Fatty acid secreted | | he | et 
by 0.10| 0.30) 0.75) 0.95) 1.30, 1.65 
action of Amm. carb. | 
Fatty acid formed by | | 
the action of lipase in | 4.25] 1.45) 4.75] 2.2 | 2.2 
cc io N: | 
2 45) 2.25 
These experiments prove that in a medium with a lactic acid 
concentration of about '/,, N no more fat-splitting by the lipase 
takes place. The action of the lipase on fat is much favoured by 
