This section is from the book "A Text Book Of Materia Medica, Being An Account Of The More Important Crude Drugs Of Vegetable And Animal Origin", by Henry G. Greenish. Also available from Amazon: A Text Book of Materia Medica : Being an Account of the More Important Crude Drugs of Vegetable and Animal Origin.
Stavesacre, Delphinium Staphisagria, Linne (N.O. Ranunculaceoe), a stout erect herb attaining 4 feet in height, is indigenous to Asia Minor and southern Europe. The plant is cultivated in France and Italy, our supplies being derived chiefly from Trieste and from the south of Italy.
Stavesacre was well known to both the Greeks and the Romans. Dioscorides mentions it, and Pliny describes its use as a parasiticide. It continued to be extensively employed throughout the Middle Ages, but is now in much less demand.
The seed, as seen in commerce, are about 6 mm. in length and rather less in breadth. They usually appear to be dark grey in colour, but when freed from the dust with which they are covered are seen to be dark brown, and then the characteristic markings on the surface of the seed become more evident. In shape they are usually irregularly or obscurely four-sided, one side being curved and larger than the others, which are nearly flat or even depressed. The surface of the seed is more or less uniformly reticulate and covered with minute papillae visible under a lens. One end of the seed is usually more pointed than the other; near the pointed end the hilum is visible as a narrow line. By soaking a seed in water and cutting it transversely just below the hilum, the minute embryo may be found embedded in a large, whitish or yellowish oily endosperm.
The seed-coat is nearly tasteless, but the endosperm is intensely bitter and acrid; the seeds have no marked odour. The student should observe
(a) The dull earthy colour of the seed,
(b) The characteristic obscurely quadrangular shape,
(c) The rough as well as pitted surface,
(d) The bitter, oily endosperm.
The seeds contain several alkaloids (in all about 1 per cent.), the most important of which are delphinine, delphisine, and delphinoidine; less important are staphisagroine, of which traces only are present, and staphisagrine, which is probably a mixture.
Delphinine, C31H49N07, is crystalline and extremely poisonous. Delphisine is amorphous, but about twice as poisonous as delphinine, while delphinoidine, which is also amorphous, is much less toxic.
The seeds also contain from 30 to 35 per cent, of fixed oil, which may be extracted either by expression (expressed oil of stavesacre) or by solvents such as petroleum spirit, etc.; in either case the oil carries with it the greater part of the alkaloids, including practically all the delphinine; these may be removed from the oil by shaking it with an aqueous solution of tartaric acid. The drug affords from 10 to 13 per cent, of ash.
Fig. 84. - Stavesacre seed, entire and cut longitudinally, showing embryo. Magnified 2 diam. (Maisch).
Stavesacre seeds are extremely poisonous, delphinine and delphinoidine resembling aconitine in action, but being weaker; the seeds are used only as a parasiticide to kill pediculi, chiefly in the form of the official ointment, the expressed oil, the powdered seeds, or an acid aqueous extract containing the alkaloid.s. Delphinine has also been employed similarly to aconitine both internally and externally for neuralgia, etc.
Delphinium Consolida, Linne, contains three alkaloids apparently not identical with those of D. Staphisagria. Delphinium Ajacis, Linne, contains ajacine and ajaconine. The large size of stavesacre seeds distinguishes them from the seeds of other species of Delphinium.