23 BRASSICA (SINAPIS) ALBA 



United States, where it has escaped and occurs as an occasional 



weed. 



DC. Syst., ii, p. 620; Syine, E. B., i, p. 125; Hook. ., Stud. FL, 

 p. 30 ; Watson, Comp. Cyb. Br., p. 104 ; Hook, f., Fl. India, i, p. 

 157 ; Gren. & Godr., Fl. France, i, p. 74; Lindl., Fl. Med., p. 92. 



Official Parts and Names. SINAPIS ; the seeds of Sinapis 

 nigra, Linn., and Sinapis alba, Linn., reduced to powder, mixed 

 (B. P.). A mixture of the seeds of both the above species 

 reduced to powder (Sinapis, Mustard) (I. P.). SINAPIS ALBA; 

 the seed of Sinapis alba (U. S. P.). 



SINAPIS ALBA. White mustard seeds are much larger than those 

 of black mustard seeds. They are roundish in form, of a yellow 

 colour, and very finely pitted in a reticulate manner on their 

 surface ; internally they are bright yellow. They are inodorous 

 when entire, and almost entirely so even when triturated with 

 water, as no volatile principle is then formed as with black mustard 

 seeds under the same circumstances. Their taste is similar to, 

 but less pungent than, black mustard seeds. 



White mustard seeds yield by expression a similar fixed oil to 

 that obtained from black mustard seeds. They also contain my rosin, 

 but no myronate of potash or sinigrin, and hence no volatile oilcan 

 be obtained from them by distillation. From the investigations 

 of Will it would appear that white mustard seeds owe their pecu- 

 liarity to the presence of a crystalline principle, called Sinalbin or 

 sulpho-sinapisin, which is a compound of three bodies, namely, 

 Sulphocyanate of Acrinyl, Sulphate of Sinapin, and Sugar. When 

 sinalbin is placed in contact with water and myrosin at ordinary 

 temperatures it is resolved into its three constituent substances ; 

 but the sulphocyanate of acrinyl, which is the active principle of 

 white mustard seeds, does not pre-exist in the seeds, and cannot 

 be obtained from them by distillation. It is owing to the presence 

 of sulphocyanic acid that the infusion of white mustard seeds 

 becomes of a bright red colour when a persalt of iron is added to it. 

 An infusion of black mustard seeds under the same circumstances 

 only assumes an orange tint. 



Medical Properties and Uses. Similar to, but milder than, 

 those of black mustard seeds. When swallowed whole they 



