10191 AGRICULTURAL CHEMISTRY AGROTECHNY. SM."> 



tlally dried while Btanding. Under such conditions a large percentage of the 



hydrocyanic acid would be retained in the fodder. 



Contrary to the results of Avery and Peters (K. S. R., 14, p. 021), the 

 enzyms of the sorghum were apparently not rend. Ted Inactive In the process 

 of curing, as shown by the tad thai the addition <»r emnlsin to the eared 



sorghum did not cause the hydrocyanic acid to be liberated in larger quan- 

 tities. 



The addition of dextrose and of maltose even in small amounts appeared to 

 f'eiard or prevent the liberation of about three-fourths of the hydrocyanic 

 acid. It is assumed that this retention is due either to a reaction between the 

 sugars and the hydrocyanic acid or to a lessening of the activity of the ensym, 

 The suggestion is made that in ease there is any doubt about the poison. .us 

 nature of the sorghum, a concentrate should be fed first in order to produce a 

 considerable quantity of dextrose and maltose which would tend to prevent 

 liberation of the hydrocyanic acid of the sorghum. 



No evidence was obtained that a part of the hydrocyanic acid exists in a 

 nonglucosidic form as claimed by YVillaman (E. S. R., 37, p. 113). 



Determinations of the acid concentrations of the green and dry sorghum 

 indicate that a slightly acid condition would exist in the paunch of ruminants 

 fed upon sorghum and that this acidity would he favorable to the action of the 

 enzyms causing hydrolysis of the glucosid with liberation of hydrocyanic 

 acid. 



New methods of preserving soy bean urease, G. M. ROBINSON and C. J. 

 Oppenheim (Jour. Lab. and Clin. Med., J, (1019), No. 7, pp. .',',S. 449).— Camphor 

 In 0.25 per cent suspension was found to preserve the activity of the soy bean 

 urease for at least 45 days, a much longer period than that of toluol or other 

 preserva fives. A permanent wet preparation of the enzym can be made by 

 triturating 20 gm. of powdered soy bean with 100 cc. of pure glycerol, perco- 

 lating the mixture through a layer of glass wool of approximately 1 in. thick- 

 ness for not less than 48 hours, and titrating the extract for innate alkalinity. 

 The extract thus prepared is said to be more active than aqueous extracts of 

 the enzym, especially when activated at 35° C. 



Mass cultures on solid media, J. Schereschewsky (Berlin. Klin. Wchnschr., 

 55 (1918), No. 41, pp. 972-974, figs. 2).— An apparatus for rapid tilling and in- 

 oculation of agar plates is described, which consists essentially of a cylindrical 

 glass vessel with outlets at the top and bottom and in which is placed a tier 

 Of 12 glass dishes, similar to the ordinary Petri dish but with inward sloping 

 sides so that each rests securely on the dish below. In the bottom of each 

 dish is an opening of from 1.5 to 2 cm. diameter, the dishes being so arranged 

 that the openings of consecutive dishes are on opposite sides. After steriliza- 

 tion the hot agar is admitted through the opening at the top of the cylinder 

 and passes through the holes in each dish to the bottom, forming on cooling a 

 thin layer of the medium in each dish. The inoculation is made by admitting 

 in a similar manner a suspension of the organism in physiological sail solution, 

 a slight rotation of the cylinder being sufficient to cover the media uniformly 

 with the suspension. The usual procedure of incubation, etc.. is then followed. 



Notes on the reactions of bacteriologic media, J. F. NoBTOH (Aincr. Jour. 

 PUb. Health, 9 (1919), No. S, pp. 190-19S).—T>nt:\ are presented on the relation 

 between the titratable acidity, using phenolphthalein as an indicator, and the 

 hydrogen-ion concentration. This relation is considered to depend entirely upon 

 the ingredients of the medium. Sterilization effected an appreciable change in 

 the reaction of neutral and alkaline media and but little change in acid media. 



123007°— 19 2 



