CRUCIFERAE BRASSICA 



489 



Fig 256. Charlock (Brassica arvensis). U. S. Dept. Agrl. Fig. 256a. Common Black 

 Mustard (Brassica nigra). U. S. Dept. Agrl. 



Medicinal and Poisonous properties. White mustard contains a glucoside 

 also found in other members of the family sinalbin, C, H 40 N S 9 O 15 -(-H 2 O, and 

 in addition, the ferment known as myrosin which converts the sinalbin into an 

 active principle, o.ry-bensyl-thiocyanate (a very acrid volatile body) sinapin 

 sulphate and glucose. The following formula represents the change that occurs : 

 C ao H 4i N 2 S 2 16 =C 6 H 12 6 +C 7 H 7 0-NCS+C 16 H 24 N0 5 -HS0 4 . 



Oxy- 

 Sinalbin Glucose benzyl-thio- Sinapin sulphate 



cyanate 



Black mustard contains the glucoside sinigrin, and a ferment, myrosin, 

 which produces the following reaction : 



C 10 H 18 NKS 2 10 = C 8 H 8 CNS + C 6 H 18 O 6 + KHSO 4 . 

 Sinigrin Sulpho-cyanate Glucose Hydrogen 



of allyl Potassium sulphate 



(Essential oil of Mustard) 



White Mustard seed when reduced to a powder and made into a paste 

 with cold water, acts as a powerful stimulant. Large doses cause vomiting. 

 Intestinal secretion is increased by the use of mustard, which is rarely used, 

 however, as an emetic because of its pungency. It is extremely valuable for 

 relieving pain or congestion. It is a splendid emetic for dogs in the spoonful 

 doses, given in warm water. Dr. Millspaugh states that in the case of black 



