สารบัญ

Category  Expectorant.

       Squill consists of the bulb of Drimia maritima (L.) Stearn  [Urginea maritima (L.) Baker] (Family Asparagaceae), collected soon after the plant has flowered, divested of its dry outer, membranous coats, cut into transverse slices and dried.  It is known in commerce as white squill.

Origin of plant  Squill is native to Mediterranean region and the Canary Islands.

Constituents  Squill contains steroid glycosides, namely bufadienolides, most importantly scillaren A and proscillaridin A. It also contains flavone glycosides such as vitexin and orientin, sterols, and mucilage.

Description  Odourless or almost odourless.
Macroscopical  Transverse slices, occurring as straight or curved triangular pieces, 5 to 50 mm long, 3 to 8 mm wide at mid-point, tapering towards each end, 5 to 8 mm thick, yellowish white, texture horny, somewhat translucent, breaking with an almost glassy fracture when quite dry, but becoming tough and flexible when absorbing moisture.  Transversely cut surface showing a row of prominent vascular bundles near the concave edge and numerous smaller bundles scattered throughout the mesophyll.
Microscopical  Powdered drug of Squill shows epidermis, mesophyll and vascular bundles.  Epidermis:  axially elongated polygonal cells; cuticle stratified; stomata very rare, anomocytic, circular in outline.  Mesophyll:  colourless thin-walled parenchyma cells containing, many of which containing bundles of acicular crystals of calcium oxalate embedded in mucilage; the rests containing sinistrin, and very occasionally starch granules.  Vascular bundles:  collateral, scattered throughout the mesophyll; xylem vessels with spiral and annular wall thickening; trichome absent.  

Other relevant information
     1. It is contra-indicated in patients who are on digitalis glycosides, and those with potassium deficiency, hypercalcemia, or hyperkalemia.
     2. It is contra-indicated in pregnant women as it may lead to spontaneous abortion.
     3. The plant, when overdosing, is an irritant poison that may cause nausea and vomiting, bloody urine, convulsions, and even death from paralysis of the heart in systole.

Packaging and storage  Squill shall be stored in a dry place at a temperature not exceeding 25°.

Identification  The mucilage contained in the cells of the mesophyll is stained red with alkaline corallin TS but produces no red colour with ruthenium red TS and no purple colour with 0.01 M iodine.

Acid-insoluble ash  Not more than 1.5 per cent w/w (Appendix 7.6).

Ethanol (60 per cent)-soluble extractive  Not less than 68.0 per cent w/w (Appendix 6.5).  Use the powdered drug, previously dried at 105° for 1 hour.

SQUILL, POWDERED

Complies with the requirements for Identification, Acid-insoluble ash and Ethanol (60 per cent)-soluble extractive described under Squill and with the following requirements.

Description  White or yellowish white; very hygroscopic.  Diagnostic structures:  abundant, acicular crystals of calcium oxalate, the larger ones frequently broken, some embedded in mucilage which is stained red with alkaline corallin TS but produces no colour with 0.01 M iodine; lignified vessels with spiral and anular thickening; fragments of epidermis with very infrequent stomata.

Packaging and storage  Powdered Squill shall be kept in tightly closed containers with suitable desiccants, protected from light, and stored at a temperature not exceeding 25°.