128 PHYSIOLOGY [Bot. Absts., Vol. V, 



be due to the oxidizing function of this enzyme. The author isolated tyrosinase from the 

 potato and studied its action upon the amino acids. He detected formaldehyde, ammonia, 

 and small quantities of carbon dioxide as decomposition products. He found that the pres- 

 ence of chlorophyll favored the action of tyrosinase. No deamination occurred when the 

 oxygen was displaced by hydrogen or carbon dioxide. The author shows that the oxidizing 

 ferment tyrosinase has the ascribed properties of the deaminase and so makes the existence 

 of a deaminate doubtful. — F. M. Schertz. 



915. Barton, Arthur Willis. The lipolytic activity of the castor and soy bean. Jour. 

 Amer. Chem. Soc. 42: 620-632. 1920. — The author finds that the lipase from the castor bean 

 splits the esters of fatty acids to a greater degree than does the soy bean lipase. Both seeds 

 contain the same lipases. When lard or olive oil is used as substrate, ether and alcohol must 

 be added before titration. Lipases from both sources act in the same ranges of acidity. — 

 J. M. Brannon. 



916. Carnot, P., and P. Gerard. Mecanisme de Faction toxique de l'urease. [Mechan- 

 ism of the toxic action of urease.] Compt. Rend. Acad. Sci. Paris 169: 88-90. 1919. — There 

 are reported experiments in vitro and in vivo using the urease of soy beans, and an explanation 

 is given of the toxic action of soy beans on the basis of the action of the urease contained in 

 them. — V. H. Young. 



917. Colin, H., and A. Chaudun. Sur la loi d'action de la sucrase. Influence de la 

 viscosite sur la vitesse d'hydrolyse. [On the law of action of sucrase: influence of viscosity 

 on the rate of hydrolysis.] Compt. Rend. Acad. Sci. Paris 168 : 1274-1276. 1919. — If saccharose 

 is in excess with relation to the enzyme sucrase, the rate of hydrolysis is proportional to the 

 viscosity of the solution. — V. H. Young. 



918. H£rissey, M. H. Sur la conservation du ferment oxydant des champignons. [The 

 preservation of the oxidizing ferment (oxydase) of fungi.] Jour, de Pharm. et Chim. 20: 241- 

 245. 1919. — The oxydases of fungi, especially of Russula delica, can easily be preserved in 

 macerations with glycerin (1 part of the sliced fungus and 2 parts of glycerin). They may also 

 be obtained by adding ether to the sliced fungus, allowing the mixture to stand for some time 

 and then drawing off the lower aqueous liquid and keeping this together with an equal volume 

 of ether, water, or glycerin in sealed tubes. The oxydases thus remain intact for more than 

 20 years and form a very important reagent for biologic tests. — H. Engelhardt. 



919. Jacoby, M. Uber den vermeintlichen Abbau der Starke durch Formaldehyde. 

 [The supposed decomposition of starch by formaldehyde.] Ber. Deutsch. Chem. Ges. 52B: 558- 

 562. 1919.- — Formaldehyde action on starch has no relation to diastatic action; that is, 

 formaldehyde is not a "diastase-model." The author disagrees with Woker and agrees with 

 von Kauffman and Sallinger on this point. — G. M. Armstrong. 



920. Kopeloff, Nicholas, and S. By all. Invertase activity of mold spores as affected 

 by concentration and amount of inoculum. Jour. Agric. Res. 18: 537-542. 1920. — Spores of 

 Aspergillus Sydowi, A. niger, and Penicillium expansum exhibit invertase activity in sugar 

 solutions of concentrations varying from 10 to 70 per cent. Maximum activity occurs in 

 concentrations between 50 and 60 per cent. An increase in the number of spores results in 

 an increased invertase activity in a saturated sugar solution. About 5000 spores of A. Sydowi 

 per cubic centimeter of saturated sugar solution cause inversion; but from 50,000 to 110,000 

 spores per cc. of the other two organisms are required. — D. Reddick. 



921. McHargtje, J. S. The significance of the peroxidase reaction with reference to the 

 viability of seeds. Jour. Amer. Chem. Soc. 42: 612-615. 1920.— The author thinks that the 

 peroxidase reaction can be made use of in seed-testing laboratories for detecting non-viable 

 seeds and for distinguishing between seed of high, medium, and low viability. Lettuce, 

 alfalfa, and soy-bean seeds contain both oxidases and peroxidases. The peroxidase can be 

 used to determine the rate at which seeds lose their viability. — J. M. Brannon. 



