I 



RECENT WORK IN AGRICULTURAL SCIENCE. 



AGRICULTURAL CHEMISTRY— AGROTECHNY. 



The germ plasm as a stereochem^ic system, B. T. Reicheet (Science, n. ser., 

 40 (1914), No. 1036, pp. (>^5-66i).— Substantially noted from another source 

 (E. S. R., 32, p. 501). 



On the colloidal swelling- of wheat gluten, F. W. Upson and J. W. Calvin 

 (Jour. Amer. Chcm. Soc, 37 (1915), No. 5, pp. 1295-1304, figs. 5).— "The experi- 

 ments described in this paper show that the mixture of vegetable proteins which 

 comprises wheat gluten behaves in a manner entirely analogous to the animal 

 colloids as studied by Fischer and others. Moist gluten absorbs water from 

 acid solutions and the amount of absorption varies with the kind and con- 

 centration of the acid. The presence of neutral salts retards water absorption 

 by gluten, and in the higher concentrations of salt may even cause loss of water 

 from moist gluten. Gluten which has taken up water in an acid solution loses 

 water and regains its original physical properties when placed in a salt solution. 

 The nouelectrolytes are much less effective than electrolytes in inhibiting the 

 swelling of gluten in acid solutions. These experiments, therefore, contribute 

 to the important problem of the mechanism of water absorption and secretion 

 by living plants, which in animals has been proved by Fischer to be essentially 

 a. colloid phenomenon." 



Studies on enzym action. — ^XHI, The lipase of soy beans, K. G. Falk (Jour. 

 Amer. Cliem. Soc, 31 (1915), No. 3, pp. 649-653). — In continuation of work pi-e- 

 viously noted (E. S. R., 32, p. 803), "the lipolytic properties of soy beans were 

 studied by the methods used in the similar studies of castor beans and of duo- 

 denal contents. A comparison of some of the properties of these hydrolytic 

 enzyms showed the following relations : 



" Roy beans contain a lipase active toward triacetin (and therefore presumably 

 toward fats), somewhat soluble in water, with a maximum solubility in 1..5 

 normal sodium chlorid solution. Castor beans contain an esterase soluble in 

 water, and a lipase insoluble in water and soluble in sodium chlorid solution 

 with a maximum solubility at the concentration 1..5 normal. Duodenal contents 

 contain an esterase and a lipase, the former predominating in the intestinal 

 juice, the latter in the pancreatic juice and bile. Marked similarities in the 

 action of neutral salts and alcohols are shown by the lipases from different 

 sources. The action of heat and of drying on the soy bean lipase was found 

 to be similar to their action on castor bean lipase and esterase. The analyses 

 of the soy bean lipase preparations showed no marked differences in comparison 

 with the analyses of the castor bean preparations." 



Further applications of the boric acid method for determining ammonia, 

 L. W. Winkles (Ztschr. Angeic. Chcm., 28 (1915), No. 10, Aufsatzteil, p. 48; 

 uhs. in Jour. Soc. Chem.. Indus., 34 (1915), No. 6, p. 278). — The author reports 

 that the method previously noted (E. S. R., 33, p. 312) can be employed for de- 



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