284 SCIENTIFIC AND APPLIED PHARMACOGNOSY 



Ground Black Mustard or Black Mustard Flour is usually pre- 

 pared from the cake which has been deprived of the hulls and part of 

 the oil. It is customary to mix some of the white mustard with the 

 black mustard, it being supposed that the excess of the ferment 

 in B. alba will change the unconverted glucoside into volatile oil 

 of mustard. It is likely, however, that the enhanced quality of the 

 product is due to the pungent and non-volatile character of the oil 

 in white mustard. 



Mustard Paste is sometimes adulterated with starches. At one 

 time, the addition of other substances was considered to be necessary 

 on account of the pungency of the drug. 



Constituents. Black mustard contains the same constituents 

 as white mustard, save that it contains more fixed oil (30 to 35 per 

 cent); less of the ferment, myrosin; and the sinalbin is replaced by 

 the glucoside, sinigrin (potassium myronate), which is present to 

 the extent of about 1 per cent and yields on interaction with the 

 myrosin a light yellowish volatile oil (allyl isosulphocyanide or vola- 

 tile oil of mustard), which has an acrid, burning taste, pungent odor, 

 and also affects the eyes. In the reaction there is also formed glu- 

 cose and potassium acid sulphate. 



The U. S. Department of Agriculture has ruled that black mus- 

 tard-seed should yield a volatile oil containing not less than 0.6 per 

 cent of allyl iso-thiocyanate. 



Allied Products. Of the seeds of the other Cruciferae, which some- 

 what resemble black mustard, the following may be mentioned: 

 The seeds of Field mustard or Brassica arvensis, which are almost 

 black and perfectly smooth; the seeds of Sarepta mustard (Brassica 

 Besseriana), which are larger and distinctly reticulate; Rape or 

 colza seeds (Brassica Napus), which are larger, not reticulate and of a 

 bluish-black color; Turnip seeds yielded by Brassica campestris, 

 which are somewhat larger but less acrid, and are used in India in 

 place of black mustard; and Brassica juncea, which is cultivated in 

 tropical Asia for the same purpose. 



Adulterants. A large percentage of the black mustard of com- 

 merce is admixed with the seeds of wild mustard or Charlock (Bras- 

 sica arvensis). The plant is very common in the wheat fields of 

 the northwestern States and the seeds are almost always present 

 in the mustard from this territory. A product known as Dakota 

 Mustard consists largely of the seeds of this plant. They are very 

 easily detected by the use of a small magnifying glass, as they are 

 brownish-black, from 1 to 1.5 mm. in diameter, nearly smooth and 

 not reticulated as true black mustard. Charlock, when admixed 



