An alkaline solution of tartrate of copper is not acted upon by sinistrin. It is transformed into sugar by boiling it for half an hour with water containing 1 per cent. of sulphuric acid. The sugar thus produced is stated by Schmiedeberg to consist of lævulose[2585] and another sugar, which in all probability, when perfectly pure, must prove devoid of rotatory power.
The name sinistrin[2586] has also been applied to a mucilaginous matter extracted from barley (see Hordeum decorticatum); it remains to be proved that the latter is identical with the sinistrin of squill.
We have obtained a considerable amount of an uncrystallizable levogyre sugar by exhausting squill with dilute alcohol.[2587] Alcohol added to an aqueous infusion of squill causes the separation of the mucilage, together with albuminoid matter. If the alcohol is evaporated and a solution of tannic acid is added, the latter will combine with the bitter principle of squill, which has not yet been isolated, although several chemists have devoted to it their investigations, and applied to it the names of Scillitin or Skuleïn. Schroff, to whom we are indebted for a valuable monograph on Squill,[2588] infers from his physiological experiments the presence of a non-volatile acrid principle (Skulein?), together with scillitin, which latter he supposes to be a glucoside.
Merck of Darmstadt has isolated Scillipicrin, soluble in water; Scillitoxin, likewise a bitter principle, insoluble in water, but readily dissolving in alcohol; and Scillin, a crystalline substance, abundantly soluble in boiling ether. The physiological action of these substances and of Scillaïn has been examined (1878) by Moeller, and by Jarmersted (1879); that of scillitoxin and scillaïn was found to be analogous to that of Digitalis.
Commerce—Dried squill, usually packed in casks, is imported into England from Malta.
Use—Commonly employed as a diuretic and expectorant.
Substitutes—There are several plants of which the bulbs are used in the place of the officinal squill, but which, owing to the abundance and low price of the latter, never appear in the European market.
1. Urginea altissima Baker (Ornithogalum altissimum L.), a South African species, very closely related to the common squill, and having, as it would appear, exactly the same properties.[2589]
2. U. indica Kth. (Scilla indica Roxb.), a widely diffused plant, occurring in Northern India, the Coromandel Coast, Abyssinia, Nubia, and Senegambia. It is known by the same Arabic and Persian names as U. maritima, and its bulb is used for similar purposes. But according to Moodeen Sheriff[2590] it is a poor substitute for the latter, having little or no action when it is old and large.
3. Scilla indica Baker[2591] (non Roxb.), (Ledebouria hyacinthina Roth), native of India and Abyssinia, has a bulb which is often confused in the Indian bazaars with the preceding, but is easily distinguishable when entire by being scaly (not tunicated); it is said to be a better representative of the European squill.[2592]