10 EXPERIMENT STATION EECOED. [Vol.35 



It is indicated tliat in general tlie greater part of silage fermentation is due 

 <o the activity of micro-organisms consisting of four prominent groups, (1) the 

 acid group, (2) the colon group, (3) yeasts, and (4) a miscellaneous type. The 

 most important fermentation is that of acid production which is largely due to 

 a group of organisms belonging to the Bulgarian group. 



The morphology and tlie cultural and biochemical features of the Bulgarian 

 group organisms are described in detail. 



On the urease of the soy bean and its " coenzym," N. Onodeka {Biochem. 

 Jour., 9 {1915), No. 4, pp. 575-590). — It has been shown that "the urease of 

 soy bean loses its activity on dialysis. The lost activity is restored by the 

 addition of a small amount of fresh urease. This indicates that the fresh urease 

 contains coenzym. The coenzym could not be separated, accordingly its nature 

 Is not yet known. It is very likely that the coenzym is a system consisting 

 of two groups of components, one of wliich is dialyzable and the other undialy- 

 zable. Tlie dialyzable component undergoes some irreversible change during 

 dialysis. 



"The coenzym consists of two parts, fixed and free. Heating and dialysis 

 destroy the free coenzym first, then the fixed coenzym. Tlie last portion of the 

 fixed coenzym is found in the precipitate produced by dialysis, resisting the 

 influence of heating and dialysis tenaciously. The inhibitory elTects of heat, 

 acid, and alkali are exerted upon the coenzym, but not upon the iirease 

 proper. In germination urease accunnilates in the germs of the soy beans in 

 large proportion, but free coenzym is absent. Although ox serum has an acceler- 

 ating power, it contains no substance which can be compared Avith the coenzym." 



On the effects of various substances (electrolytes, nonelecti'olytes, alka- 

 loids, etc.) upon the urease of soy bean, N. Onodeka (Biochem. Jour., 9 

 {1915), No. 4, PP- 5ji4-571f, figs. 2). — The experimental data demonstrate that in 

 the inhibitory effects of inorganic and organic acids on urease the hydrogen ion 

 concentration plays a very important role, but does not coincide with this In 

 the inhibitory effects of caustic soda and ammonia. The inhibitory effect of 

 soda can be ascribed to the hydroxyl ion concentration, but ammonia has some 

 further action. Methyl, ethyl, and propyl alcohol in 1-molar solutions and amyl 

 alcohol in ^ -molar solution accelerate the urease action, but stronger solu- 

 tions retard the action. Aldehyde inhibits urease notably. The effect of 

 neutral salts is due to their metallic bases. Tenth-normal solutions retard 

 urease action because metallic bases displaced by the ammonia produce a 

 greater hydroxjd ion concentration than the equivalent of ammonia. Alkaloid 

 salts accelerate the action in the the first stage of hydrolysis. The bases, how- 

 ever, markedly inhibit the action. 



Factors influencing catalase in milk, H. M. Hoyberg {Ztschr. Fleisch. n. 

 Milehhyg., 26 {1915), Nos. 5, pp. 70-71; 6, pp. 85-88; 26 {1916), No. 7, pp. 104- 

 106). — The author concludes that the catalase activity of milk and serum is 

 dependent on the protein, probably the albumin. Serum and milk can possess 

 catalase properties in the absence of bacteria, cell elements, and fibrin. The 

 catalase activity did not change in milk which has stood for 10 hours at 15° C. 

 (.59° F.), and in some cases an increase was evident. The activity was 

 Increased in many cases by heating to 45", and at 68° the catalase is destroyed. 

 Changes in the reaction of the milk do not affect the catalase, which is appar- 

 ently contrary to the enzym theory of action. 



Notes on the catalase reaction of milk, H. B. Taylob (Jour, and Proc. Roy. 

 Hoc. N. »S'. M^alcs, 48 {1914), No. 3, pp. 319-332).— In the course of an investi- 

 gation on the physico-chemical constants of milk the author has observed that 

 the velocity constant in the catalase reaction varies considerably in different 



