AGRICULTURAL CHEMISTRY AGROTECHNY. 711 



noted (E. S. R., 30, p. 806), the selective lipolytic actions of glycin, alanln, 

 plienylalanin, and castor beau lipase on metliyl, etiiyl, glyceryl tri- and phenyl 

 acetates, ethyl butyrate, and ethyl and phenyl benzoates have been compared, 

 and that of castor bean lipase on castor oil and olive oil has been measured. 



It is shown that the selective lipolytic action of glycin on methyl acetate and 

 ethyl butyrate is more marked in the preseuce of certain concentrations of hydro- 

 chloric acid. This selective action was measured. With the glycin-hydrochloric 

 acid solution used, the hydrolysis of methyl acetate and. ethyl butyrate was not 

 l)roportional to the hydrogen ion concentrations of the solution, and the dis- 

 jiroportionality, which was measured, was comparatively large. 



Studies on enzym action. — IX, Extraction experiments with, the castor 

 bean lipase, K. G. Falk {Jour. Amer. Chem. Soc, 35 (WIS), No. 12, pp. 1904- 

 1915). — "The result of extraction experiments in which the lipolytic activities 

 of the filtrates and residues of a castor bean preparation after treatment with 

 water, 0.1 molar sodium fluorid, molar sodium chlorid, and molar methyl 

 alcohol solutions, were tested toward ethyl butyrate and triacetin, confirmed 

 the conclusion given in the fifth and sixth papers [E. S. R., 20, pp. 409, 806] 

 that the inhibiting actions of these solutions on the lipase were due to precipi- 

 tating or coagulating actions. 



" Two lipases were shown to be present in the preparation. One of these 

 was soluble in water, the other insoluble. The former exerted a comparatively 

 greater action toward ethyl butyrate than toward triacetin, the latter a greater 

 toward triacetin than toward ethyl butyrate. 



" Extraction experiments with solutions of magnesium and manganous sul- 

 phates which showed acceleration with unfiltered preparations indicated that 

 the accelerations were due mainly to the action of the salts on the residues. 

 Filtration also appeared to decrease the accelerating actions of these salts." 



Quantitative investigation with reference to the action of monochromatic 

 ultraviolet rays upon amylase, A. and Mme. Chauchaed {Compt. Rend. Acad. 

 Sci. [Paris], 156 {WIS), No. 24, pp. 1858-1860; abs. in Chem. Ztg., 37 {1913), 

 No. 108, p. 1036). — The photochemical action of ultraviolet rays upon amylase is 

 proportional to the absorption of these rays by the solution in which the fer- 

 ment is held. A portion of the radiant energy in the experiments was capable 

 of raising the temperature of the solution 0.25° C. and decomposed four-tenths 

 of the enzym present. 



The influence of salicylic acid upon the amylolytic action of aqueous 

 extracts of malt, E. Heusch {Arch. Farmacol. Sper. e Sci. Aff., 13 {1912), No. 7, 

 pp. 307-323, fig. 1; abs. in Zenthl. Biochem. u. Biophys., 14 {1912), No. 7-8, 

 p. 297). — Acids play an important part in the hydrolysis of starch to maltose 

 because when present in small amounts they increase the activity of maltase, 

 while large quantities inhibit the activity. Salicylic acid is the most prominent 

 in this regard, because of the presence of a phenol radical in the molecule. 



About the biolytic cleavage of gluten, V. S. Sadikova {Zhur. Russ. Fiz. 

 Khim. Obshch., Chast Khim., 44 {1912), No. 5, pt. 1, pp. 1026-1053; abs'. in 

 Chem. Ztg., 37 {1913), No. .^7, Repert., p. 220).— Proteus vulgaris and Penicil- 

 lium glaucum, when acting upon gluten, produce more volatile acids and bases 

 than do either acids or enzyms. The experiments also show that P. vulgaris 

 and P. glaucum assimilate atmospheric nitrogen when grown on a gelatin plate. 



Measurement of tryptic protein hydrolysis by determination of the tyrosin 

 liberated, S. J. M. Auld and T. D. Mosscrop {Jour. Chem. Soc. [London], 103 

 {1913), No. 6O4, pp. 281-284; abs. in Analyst, 38 {1913), No. 445, p. 153).— The 

 method is a modification of that described by Brown, Millar, and others, which 

 consists of the estimation of the absorption of bromin by the tyrosin liberated. 



