No. 1, August, 1920] PHYSIOLOGY 127 



that the time required for 1 he hydrolysis of starch to dextrine under the action of salivary 

 ferments is conversely proportional to the quantity of ferment. Saccharification is in no way 

 parallel to dextrin formation but remains behind if the quantity of ferment is decreased. It 

 is believed that the diastase enzyme consists of two components; an amylase which splits 

 the starch molecule to dextrine, and a dextrinasc which can attack only the dextrin group. — 

 F. M. Schertz. 



911. Anonymous. [Rev. of: Bijsdermann, W. Fermentstudien. II. Mitteilung. Die 

 Autolyse der Starke. (The autolysis of starch.) Wochenschr. Braucrci 34: 1S3-1S0. 1917.] 

 Biedermann's Zentralbl. Agrikulturchem. 47: 280-2X1. 1918. — The reviewer indicates that 

 previous work of Biedermann shows the rapid hydrolysis of boiled starch solution by saliva 

 ash, which effect is due to a ferment liberated from the starch. It is now shown, according 

 to the reviewer, that a similar hydrolysis occurs without adding any ash, if the starch solution 

 is made at 70-90°C Boiled solutions are hydrolyzed after a longer period, while extracts 

 prepared by grinding starch in water hydrolyze rapidly. The diastatic power of the latter 

 extract is similar to that of a very dilute solution of saliva, and completely transforms starch 

 into sugar. Of the salivary salts calcium chloride promotes maximum diastatic action. 

 The action of salivary ash in promoting the decomposition of starch solutions which have 

 been subjected to boiling suggests that this mixture of salts promotes the formation of amylase 

 from starch. — F. M. Schertz. 



912. Anonymous. [Rev. of: Jacoby, Martin. Uber Fermentbildung. (Formation of 

 enzymes.) Biochem. Zeitschr. 79: 35-50. 1917.] Biedermann's Zentralbl. Agrikulturchem. 

 47: 281-282. 1918. — -Traces of grape sugar were found to greatly increase the activity of en- 

 zymes on urea. Search was then made to see what building stones the enzymes used. Ac- 

 cording to the reviewer there were then tested a number of materials in relation to their action 

 on the decomposition of urea. The formation of urease was greatly stimulated by d-glucose, 

 d-galactose, glycerol, dl-glyceric aldehyde, dihydroxy acetone, pyroracemic acid, and lactic 

 acid. A stimulatory action of less intensity was shown by d-fructose, d- and 1-arabinose. 

 Maltose, ethylene glycol, and propylene glycol produced little action, while d-mannose, 

 d-sorbose, rhamnose, heptose, the polysaccharides, glucosides, and sugar alcohols had no 

 action.— F. M. Schertz. 



913. Anonymous. [Rev. of: Lombbroso, Ugo. Uber die Reversibilitat der Enzym- 

 wirkungen. 1. Mitteilung. Spaltung und Synthesis der Fette durch eine Lipase. (Cleavage 

 and synthesis of fats by the action of one and the same lipase.) Arch. Pharmacol. Sperim. 14: 

 429-459. 1912.] Biedermann's Zentralbl. Agrikulturchem. 47: 287. 1918.— According to the 

 reviewer it is shown that fat hydrolysis begins immediately at 37°C. and can proceed to SO 

 per cent of completion. Synthesis does not begin till after 30-40 hours and then does not 

 proceed to a very great extent. The presence of bile neither increases nor retards the syn- 

 thesis of fat but increases the hydrolysis. Warming at 40°C. for several hours destroys the 

 lipolytic properties but the synthetic activities are not affected. The presence of glycerin 

 lessens the harmful action of heat while oleic acid has no influence. The synthetic power of 

 pancreatic juice is not increased if either glycerin or oleic acid remains in contact with it for 

 a long time. Pancreatic juice which possesses synthetic properties has only small lipolytic 

 capacities. Addition of fat slows down the synthetic activities but does not inhibit them. 

 No synthesis could be demonstrated with the secretion of the small intestine in spite of a 

 well developed lipolytic property. — F. M. Schertz. 



914. Anonymous. [Rev. of: Schweizer, Karl. Zur Kenntnis der Desaminierung. 

 (Deamination.) Biochem. Zeitschr. 78: 37-45. 1917.] Biedermann's Zentralbl. Agri- 

 kulturchem. 47: 282. 1918. — The setting free of ammonia (deamination) in the final stages 

 of protein decomposition has been ascribed to the action of deaminases which, however, have 

 not been isolated. A hydrolytic action was ascribed to the deaminase. Chodat and Schweizer 

 in 1913 showed that tyrosinase possessed deaminizing properties and that deamination may 



