Source, Etc

Golden seal, Hydrastis canadensis, Linne (N.O. Ranun-culacece), is a small herbaceous plant with perennial rhizome, widely distributed in woods in Canada and the eastern United States, being collected in Ohio, Minnesota, West Ontario, Georgia, and Missouri. It has been successfully cultivated in Europe (Holland, Switzerland). The plant produces but a single leaf, or two leaves and a single flower. The rhizomes are collected in the autumn after the leaves have withered; as the stems persist for some time to ripen the fruits, the remains of them are frequently found attached to the drug. The introduction of the drug into American and European medicine has been of very recent date, although its yellow colour had long attracted attention.

Description - The drug consists of small yellowish brown rhizomes varying from 1 to 4 cm. in length and averaging about 5 mm. in thickness; although they appear to be horizontal and creeping they are often oblique or even erect, as is indicated by the direction of the buds with which some of the branches terminate, as well as by the presence of rootlets on the (apparently) upper as well as under surface. They are knotty, tortuous, and rough, frequently giving off short upright branches terminated by cup-shaped scars left by the aerial stems of previous years. These branches usually bear distinct encircling scars of cataphyllary leaves, and similar scars are borne by the rhizome also, although there they are less distinct.

Thin, shrivelled, wiry, brittle roots of the same colour as the rhizome proceed from all parts of it, but especially from the lateral and ventral surfaces. Many of them break off, leaving small protuberances on the rhizome, which is often therefore rough and comparatively free from roots.

The rhizome is hard, and breaks with a short resinous fracture. The transverse section varies in colour from dark yellow to very dark yellowish brown, and exhibits a comparatively thick bark 1 and a ring of bright yellow, somewhat distant narrow wood-bundles surrounding a large pith. The root also exhibits a dark bark and small, bright yellow wood.

The drug has a faint but characteristic odour; when it is chewed a bitter taste is developed and the saliva is coloured yellow.

The student should observe and should compare the drug with Bloodroot, which usually has a dark reddish brown colour, and exhibits in transverse section a more or less prominent red colour without evident wood-bundles.

(a) The yellow colour,

(b) The structure visible in the transverse section when examined with a lens.

(c) The characteristic odour;

Source Etc 221Fig. 143.   Hydrastis rhizome. Natural size. (Pharmaceutical Journal.)

Fig. 143. - Hydrastis rhizome. Natural size. (Pharmaceutical Journal).

1 I have employed the term ' bark' to designate the collection of tissues exterior to the cambium of the rhizome and root as well as of the stem (compare p. 233). The Pharmacopoeia has adopted the word ' cortex,' but this is liable to misinterpretation owing to the restricted sense in which the term is employed by modern botanists. For the tissue exterior to and including the endodermis (in monocotyle-donous rhizomes) I have used the term ' cortex,' which is correct both in its ordinary and its botanical sense.

Constituents

The principal constituents of golden seal are the alkaloids hydrastine, berberine, and canadine. The drug contains in addition resin, starch, and a trace of volatile oil. It leaves from 5 to 8 per cent, of ash on incineration.

Hydrastine, C21H11NO6 (1.5 to 3.2 per cent.), crystallises in colourless bitter prisms melting at 132°. It yields by oxidation hydrastinine, C11H13NO3, and opianic acid, C10H10O5, the latter body being also obtained when narcotine is boiled with solution of potassium hydroxide, thus indicating a close relationship between hydrastine and narcotine, the latter differing only by the presence of a methoxy group.

Canadine (xanthopuceine), C20H11NO4, forms colourless crystals melting at 132° and becoming yellow when exposed to the light. Berberine (compare p. 235) occurs to the extent of about 3 per cent.

Uses

Hydrastis rhizome is a bitter tonic resembling nux vomica. It also exerts an astringent action due to the alkaloid hydrastine. It is used as a stomachic and nervine stimulant, in menorrhagia and inflammation of the uterine mucous membrane, and is employed locally in various kinds of ulceration and haemorrhage.

Adulterants

Accidental admixture of other rhizomes such as that of Aristolochia Serpentaria, Linne, Stylophorum diphyllum, Nuttall, Cypripedium parviflorum, Salisbury, have been observed, but they are all easily detected.