134 Journal of Agricultural Research vol. xx, no. t 



isothiocyanate : i cc. the first day, 1.5 cc. the second day, and 2 cc. the 

 third day. Except for an increased urine excretion, no disturbance was 

 observed; the urine was free from albumen. In experimenting with 

 cattle, Moussu (30) used the pure oil of allyl isothiocyanate as well as 

 cakes containing crotonyl isothiocyanate. Concerning allyl isothio- 

 cyanate given internally, he concludes that it is very toxic and may cause 

 in doses of 2 gm. per 100 kilos speedy death, with the symptoms of an 

 acute inflammation of the intestines. 



No injury was observed from feeding large and varying amounts of 

 rape-seed cakes, either dry or mixed with water, though cows of different 

 ages were fed with the cakes which, according to Brioux (6), contained 

 over % per cent of crotonyl isothiocyanate. One old cow, not in milking 

 condition, weighing about 400 kgm., was fed in four periods of five days 

 each the amount of 1 kgm. of cake per day, increasing to 3 kgm. per day. 

 Apparently no injury was caused, although the cow received in the final 

 period about 17 gm. of crotonyl isothiocyanate in the form of a cake, 

 yielding 0.57 per cent of this oil. Brioux, on the basis of Moussu's 

 experiments, concludes that allyl isothiocyanate is six or seven times as 

 toxic as crotonyl isothiocyanate. He pointed however, to the fact 

 that Moussu fed the volatile oil of allyl isothiocyanate directly, while 

 previous authors, using the mustard cake, could feed without causing 

 injury to the animal amounts which contained decidedly larger quanti- 

 ties of volatile mustard oil. For other experiments with allyl mustard 

 oil see Carlier (9). 



BACTERICIDAL ACTION 



The bactericidal effect, so strong in the case of allyl mustard oil and 

 so essential for the keeping qualities of prepared mustard, as Kossowicz 

 (24, p. 329) and others have pointed out, is lacking or very weak so far 

 as crotonyl isothiocyanate is concerned. Stein made the following inter- 

 esting experiments. 



To a number of test tubes containing 10 cc. of raw milk a small amount 

 (on point of knife) of liver of sulphur and also increasing but definite 

 amounts of allyl isothiocyanate and crotonyl isothiocyanate, respec- 

 tively, were added. A test paper, moistened with lead salt solution, 

 was fastened in the opening of the tube. The opening was then closed 

 with cotton, and the tubes were set aside at from 38 to 40 C. for 24 

 hours. The blackening of the lead paper, caused by the bacterial 

 formation of hydrogen sulphid and subsequent formation of lead sulphid, 

 indicated in which experiments bacterial activity was not inhibited by 

 the addition of either of the volatile oils. His results are given in 

 Table VI. 



The far greater bactericidal effect of allyl mustard oil is clearly evident. 

 Further interesting data on the bactericidal action of allyl mustard oil 

 and the amounts which prevent the growth of bacteria or yeasts belonging 

 to different species are reported by Kossowicz (23, p. 149-161). 



