Cinchona bark 2026-10-31
Medicinal bark obtained from specified species of Cinchona; a historical source of quinine and related cinchona alkaloids.
Decoction suits material whose useful constituents are water-soluble and withstand boiling; infusion avoids sustained boiling and can better preserve delicate or volatile constituents. The choice depends on both the plant's structure and the chemistry of the constituent being extracted.
Hard bark, wood and many kinds of root need comminution and more prolonged contact with hot water to penetrate their tissues; a decoction can assist extraction when the desired material is stable. Boiling is unsuitable when it drives off a needed volatile oil, decomposes the active constituent, or extracts an unwanted excess of starch or other material. A hard root is therefore not automatically an instruction to boil. Period examples suitable for decoction include oak bark, logwood and pareira root; appropriate infusions include aromatic cloves and chamomile. Cold infusion of calumba avoids dissolving its starch, illustrating that suitability depends on the desired selectivity of solvent extraction, not merely on whether a drug is a leaf or a root. [ref]
For an infusion, the appropriately divided drug is left in a measured solvent for a prescribed time, commonly in a covered vessel. Hot water assists extraction, while a cover reduces loss of volatile matter. Cold infusion can be chosen when heat is undesirable. The result must be strained or filtered; time, temperature, particle size and solvent quantity affect its strength. Neither method guarantees that every constituent is extracted in the same proportion.
A liquid extract is made by extracting the specified drug with a suitable solvent, separating the liquid from the exhausted material, and bringing the extract to its prescribed concentration and volume. Maceration can precede percolation; expression or washing recovers retained liquid. A percolator passes fresh solvent through a packed bed, rather than indefinitely soaking the drug in an increasingly saturated liquid. Where concentration is necessary, controlled evaporation limits damage; an alcoholic fraction can be reserved or recombined as the monograph directs. Different liquid extracts can use aqueous, alcoholic or ethereal processes. For example, the liquid extract of male fern is an ethereal extraction of a resinous and oily fraction, whereas the liquid extract of opium is compounded from a previously made aqueous extract. These are chemically different operations. There is no warrant for assigning all 1864 extracts one modern universal drug-to-extract ratio. [ref]
The Prescriber's Analysis of the British Pharmacopoeia by John Birkbeck Nevins (1864). pp. 20–21 and 42–43, differing liquid extracts and strengths; p. 15, percolation
The required sequence is fresh flowers; sliced and dried bulb; unexpanded petals; heartwood; seeds; expressed seed fat; expressed seed oil; and fresh and dried root. The plant organ, its state, and the actual official material must all be specified.
- Sambucus nigra: fresh flowers. The official article is Sambuci flores, elder flowers, gathered from the native plant. The flower stalks are separated when making elder-flower water; the preparation also allows an equivalent quantity of flowers preserved fresh with common salt. Neither elder berries nor elder bark answers the botanical part asked here.[ref]British Pharmacopoeia by the General Medical Council (1867). “Sambuci flores”, p. 274; “Aqua sambuci”, p. 45
- Squill: the sliced and dried bulb. The historical botanical source is Urginea scilla, also identified there as Scilla maritima. The medicinal slices consist of the fleshy bulb scales; this is an underground shoot structure, not a root. The official article is Scilla.[ref]British Pharmacopoeia by the General Medical Council (1867). “Scilla”, pp. 279–280
- Rosa gallica: the fresh and dried unexpanded petals. These are Rosæ gallicæ petala, the red-rose material. “Unexpanded” refers to collection before the flower has opened fully. The petals must be distinguished from the rose hip used for a different official preparation.[ref]British Pharmacopoeia by the General Medical Council (1867). “Rosæ gallicæ petala”, red-rose monograph
- Pterocarpus santalinus: the sliced or rasped heartwood. This is Pterocarpi lignum, red sandalwood. The answer is the wood, rather than bark or the exudate known as kino. Botanical relationship between two medicinal materials does not make their official definitions interchangeable.[ref]British Pharmacopoeia by the General Medical Council (1867). “Pterocarpi lignum”, p. 261
- Physostigma venenosum: the seed. Physostigmatis faba, the Calabar bean, is botanically a seed, not the entire pod. Its two large cotyledons lie inside a hard seed coat. The official alcoholic extract is made from the powdered seed.[ref]British Pharmacopoeia by the General Medical Council (1867). “Physostigmatis faba”, pp. 233–234; “Extractum physostigmatis”, p. 126
- Theobroma cacao: the concrete oil obtained by expression and heat from the ground seeds. The official article is Oleum theobromæ, cocoa butter. Naming the seed gives its source organ, but omits the important fact that the official pharmaceutical material is the separated fat. It is distinct from coconut oil.[ref]British Pharmacopoeia by the General Medical Council (1867). “Oleum theobromæ”, p. 229
- Croton tiglium: the oil expressed from the seeds. The official material is Oleum crotonis, croton oil, rather than the whole plant or an unspecified leaf preparation. The seeds are its source; the expressed oil is the article used in the official formulations.[ref]British Pharmacopoeia by the General Medical Council (1867). “Oleum crotonis”, p. 222
- Taraxacum officinale: the fresh and dried root. The official article is Taraxaci radix, dandelion root, called Taraxacum dens leonis in the 1867 standard, gathered between September and February from British meadows and pastures. The collection season and fresh/dried distinction belong to the historical standard; the answer is not the leaves or flowers.[ref]British Pharmacopoeia by the General Medical Council (1867). “Taraxaci radix”, p. 317
The names in the paper sometimes use the shorter terminology of the first British Pharmacopoeia, whereas the 1867 edition explicitly renamed many entries to identify the medicinal organ. Its alteration list, for example, maps Sambucus to Sambuci flores, Pterocarpus to Pterocarpi lignum, and Taraxacum to Taraxaci radix.[ref]
British Pharmacopoeia by the General Medical Council (1867). “Articles the names of which have been altered”, pp. xix–xxi
That is a nomenclature change, not permission to choose any part of the named plant.TODO: specimens A–E are missing; their identities and observed characters cannot be recovered from the paper. The scanned volume supplies no description, illustration, label key, or preserved samples for those five articles. Each identification and its specimen-specific description therefore remains incomplete.
A valid examination of the missing materials would first record each label separately and describe the actual material: whole or powdered form; size and shape; external and cut surfaces; texture and fracture; and any diagnostic plant organ or animal structure. For a botanical material, microscopy could distinguish bark, wood, root, leaf and seed tissues, with suitable reference material and the historical pharmacopoeia definition used for comparison. A putative chemical preparation would instead require appropriate solubility and reagent tests. No colour, smell, section, chemical reaction, botanical origin or medicinal constituent is asserted for an unseen sample. Historical descriptions involving tasting are documentary evidence, not a method to apply to unknown potentially poisonous materials.