Oleum Sinapis. - Senfol. - Essence de Moutarde.
Origin. Black mustard is the designation applied to the seeds of Brassica nigra, Koch (Sinapis nigra, L.) and Brassica juncea, Hooker fil. et Thomson (Sinapis juncea, L), family Cruciferae. Brassica nigra belongs to the European-Asiatic floral area. For the sake of the seed, it is cultivated in most civilized countries, but particularly in Holland, Apulia and the Levant. Brassica juncea, however, is cultivated even on a larger scale in Sarepta, in the Russian government-Saratow, in East India and in North America1). By far the largest amount of seed is used for the preparation of table mustard, a much smaller amount for medicinal purposes and for the distillation of mustard oil.
Commercial seed is frequently a mixture of seeds of different species and is sometimes admixed with the seeds of weeds. Inasmuch as the determination of the parent plant is frequently desirable, reference should here be made to an extensive investigation by C. Hartwich and A. Vuillemin2). Not. only does the report contain an exhaustive reference to the literature on the subject, but all questions that may come into consideration, such as the anatomical relations of the several seeds, are discussed in detail. Of special value is a table for the determination of the several species based on the microscopic structure of the seed shells.
Production. Mustard oil as such is not contained in the seed, but is formed by a process of fermentation. First the ground seeds") are deprived of their fatty oil as completely as possible steam. The yield amounts to from 0,5 to more than 1 p.c. of the original seed.
1) Concerning the quantities of mustard seed imported at Hamburg between 1897 and 1909, also concerning their source, a geographical and statistical paper by O. Tunmann supplies interesting information. Apotheker Ztg. 26 (1911), 580.
2) Apotheker Ztg. 20 (1905), 162, 175, 188, 199.
3) According to the fifth edition of the German Pharmacopoeia (comp. also vol. I, p. 605), the mustard oil assay of the seed is conducted in the following manner: To 5 g. of powdered black mustard contained in a flask, 100 cc. of water, having a temperature of from 20 to 25°, are added. The by hydraulic presses. The crushed oil cakes are mixed with lukewarm water and allowed to ferment for some time. As soon as the fermentation is completed, the oil formed is distilled with stoppered flask is set aside for two hours, being shaken repeatedly. 20 cc. of alcohol and 2 cc. of olive oil are then added and the mixture distilled, taking special care to cool the distillate. The 40 to 50 cc. distilling over first are collected in a 100 cc. flask containing 10 cc. of ammonia, and 20 cc. of 1/10-N-silver nitrate solution are added. The opening of the flask having been covered with a small funnel, it is heated in a water-bath for an hour. After cooling, the contents of the flask are diluted to 100 cc; 50 cc. of the clear filtrate, to which 1 cc. of nitric acid and 1 cc. of ferric ammonium sulphate have been added, should require at most 6,5 cc. of 1/10-N-ammonium sulphocyanate solution to produce a red color. This corresponds to 0,7 p. c. allyl mustard oil (1 cc. of 1/10-N-silver nitrate solution = 0,004956 g. of allyl mustard oil, using ferric ammonium sulphate as indicator).
From the results obtained by D. Raquet (Ann. Chim. analyt. appl. 17 (1912), 174; Chem. Zentralbl. 1912, II. 457) in an investigation on the analysis of mustard oil in mustard seed, it becomes evident that it is preferable to replace the aqueous maceration by an alcoholic one. According to Raquet, 5 g. of ground mustard seed, 100 cc. of water and 20 cc. of 90 p.c. alcohol are mixed in a flask of 250 cc. capacity, the flask stoppered and heated for an hour from 30 to 35° or set aside at room temperature for 6 hours with frequent shaking. The distillation is conducted from a glycerin bath, the distillate being collected in a 100 cc. measuring flask containing 10 cc. of ammonia (d15° 0,925). After about 50 cc. have distilled over, 20 cc. 1/10-N-silver nitrate solution are added, the mixture is shaken and the distillation continued until the 100 cc. mark has been reached. The flask is then connected with a reflux condenser and heated to 80 or 85° for an hour. After cooling any loss of water is replaced and the mixture filtered through filter paper free from chlorine. As usual, 50 cc. of the filtrate are titrated with 1/10-N-ammonium sulphocyanate solution. If N represents the number of cc. consumed, 10 - N the number of cc. of 1/10-N-silver solution, then (10 - .N) 0,198 is the amount of allyl mustard oil obtained from the 100 g. of powdered mustard seed.
According to this method English mustard yielded 1,386 p.c, Greek 1,198 p.c, that of Merville 1,08 p.c, Sicilian 0,99 p.c, that of Bari 0,99 p.c and Bombay mustard 0,81 p.c of allyl mustard oil.
Comp. E. Dieterich, Helfenberger Annalen 1896, 332. - J. Gadamer, Arch, der Pharm. 235 (1897), 58; 237 (1899), 110, 372. - P. Roeser, Journ. de Pharm. et Chim. VI. 15 (1902), 361. - R. Firbas, Zeitschr. d. allg. osterr. Apoth. Ver. 42 (1904), 222; Apotheker Ztg. 19 (1904), 53; Report of Schimmel & Co. April 1906, 45. - Schlicht, Pharm. Ztg. 48 (1903), 184. - A.Vuillemin, Pharm. Zentralh. 45 (1904), 384. - C. Pleijel, Apotheker Ztg. 22 (1907), 521. -M. Kuntze, Arch, der Pharm. 246 (1908), 58. - H. Penau, Journ. de Pharm. et Chim. VII. 6 (1912), 160.
At a temperature above 70° fermentation no longer takes place, since the myrosin coagulates and becomes inactive.
It has been claimed that black mustard does not contain sufficient myrosin to hydrolyze all the glucoside sinigrin present. In order to obtain better results, the addition of some white mustard to the fermentation mixture has been recommended. The investigations by H.J. Greenish and D. J. Bartlett1) in respect to this have demonstrated that this supposition is wrong. Mot only do the seeds contain sufficient myrosin to hydrolyze the sinigrin present, but the amount of this enzyme is so great at times that it suffices to hydrolyze thirteen times the quantity of sinigrin present in the seeds. The addition of white mustard during the fermentation does not improve the yield of oil.