Synonyms.—Cola Seeds; Gooroo Nuts; Bissy Nuts.
Kola seeds are obtained from Cola vera, Schumann (N.O. Sterculiaceae), a large tree growing wild in Sierra Leone, North Ashanti, near the sources of the Niger, etc., and cultivated in West Africa as well as in the West Indies, Brazil, and Java. Several varieties of kola seeds, derived from different species of Cola, are known, but for medicinal use those derived from Cola vera are generally used, and should be preferred. West Africa and the West Indies supply the commercial drug. The fruit of the tree is a large, woody capsule, containing several large, white (or sometimes crimson) seeds. For exportation to Europe, these are deprived of their seed-coats and dried, during which process they acquire a reddish-brown colour. Large quantities of the seeds are employed in their fresh state in Africa, where they are highly valued on account of their sustaining properties, and where they form a most important article of inland commerce. The drug consists of the kernel of the seed, usually separated into its two cotyledons. These are from 2.5 to 5.0 centimetres long, plano-convex, and of a dull reddish-brown colour, but internally somewhat paler. They are easily cut with a knife, and exhibit a perfectly uniform section. Fresh kola seeds have a bitterish, astringent taste, but this is lost during the drying, the dried seeds being almost odourless and tasteless. Kola seeds with four cotyledons are occasionally seen on the market. They are the seeds of Cola acuminata, Schott and Endl., a tree growing in Cameroon and Congo, and are employed in the same way as the seeds of Cola vera, but are not so highly esteemed. Seeds with six cotyledons are also met with; these are derived from C. Ballayi, Cornu, and contain but little caffeine.
Constituents.—The most important constituents of fresh kola seeds are caffeine (2 to 2.5 per cent.), kolatin, and traces of theobromine. Kolatin is crystalline, only slightly soluble in water, but readily in alcohol. The fresh seeds contain it to the extent of 0.75 per cent.; but, as it is readily converted into kola red by an oxydase present in the seeds, the dried seeds contain little or none. If, however, the oxydase be destroyed by boiling before drying the seeds, the latter remain colourless and contain kolatin. As this substance has a distinct physiological action, it follows that both the fresh seeds and the seeds dried after sterilisation differ in effect from the dried seeds of commerce. It has been stated that the seeds contain a glucoside named kolanin, but this substance appears to be a mixture of kola red and caffeine. It has been given in doses of 1 to 3 decigrams (2 to 5 grains). The seeds contain also starch, fatty matter, sugar, and a lipase or fat-decomposing enzyme, which acts on almond, arachis, castor, cotton-seed, olive, sesame, and theobroma, oils.
Action and Uses.—The properties of kola are virtually those of caffeine, modified slightly by the astringent matter present. The powdered drug is prepared in the form of chocolate and cocoa for its stimulating and sustaining properties; some proprietary cocoas, formerly much advertised as beverages, contained a certain proportion of kola. Pastilles of kola are prepared, and have a similar action. Liquid preparations are Extractum Kolae Liquidum, Tinctura Kolae, and Vinum Kolae. The liquid extract is the more commonly used; it may be combined with liquid extract of coca, as a stimulant to ward off fatigue, or with antipyrine for use in migraine, mucilage being added to suspend resinous matters.
Dose.—1 to 3 grammes (15 to 45 grains).
- Elixir Kolae, B.P.C.—ELIXIR OF KOLA. 1 (liquid extract) in 10.
- A tonic and cerebral stimulant. Dose.—2 to 4 mils (1/2 to 1 fluid drachm).
- Extractum Kolae Liquidum, B.P.C.—LIQUID EXTRACT OF KOLA. 1 in 1.
- Given as a tonic and stimulant, sometimes mixed with liquid extract of coca. Dose.—6 to 12 decimils 10 to 20 minims).
- Tinctura Kolae, B.P.C.—TINCTURE OF KOLA. 1 in 5.
- Given as a cerebral stimulant in headache. Its action is similar to that of caffeine. Dose.—1 to 4 mils (15 to 60 minims).
- Vinum Kolae, B.P.C.—KOLA WINE. 1 (elixir) in 8.
- Used as a stimulant in nervous headache and migraine. Its action is due to caffeine. Dose.—15 to 30 mils (1/2 to 1 fluid ounce).
The British Pharmaceutical Codex, 1911, was published by direction of the Council of the Pharmaceutical Society of Great Britain.