21- Digitalis Leaf (Folium Digitalis) "Foxglove Leaves" Origin: the dried leaves of Digitalis purpurea F. Scrophulariaceae, collected and rapidly dried at temperature not exceeding 65 oC.Morphology: leaves are ovate, petiolate with crenate margin, obtuse apex and decurrent base, the lamina shows chequered appearance.
3Powder: dark green, tea- like odour and very bitter persistent taste, shows fragments of: epidermis with anomocytic stomata.Non-glandular multicellular uniseriate hairs.Glandular hair, unicellular stalk bicellular head.Spiral and annular xylem vessels.
4Active constituents:1- Cardiac glycosides: Purpurea glycosides A and B:
52- Saponins: gigitonin3- Flavonoid glycoside: luteolinUses: cardiotonic and diuretic, increases the force of systolic contractibility and improves the tone of cardiac muscle, so used in treatment of congestive heart failure and auricular fibrillationN.B. digitoxin is cumulative and highly toxic, it should be administered with great care.
6Digitalis lanata "Grecian Foxglove" A substitute for Digitalis purpurea leaves.Active constituents:Cardiac glycosides: lannatoside A (Acetyl purpurea A), lannatoside B (Acetyl purpurea B) and digitoxin, gitoxin.N.B. they are twice to four times as active as official drug.
82- Strophanthus SeedOrigin: the dried seeds of Strophanthus kombe, S. gratus and S. hispidus F. Apocyanaceae.Morphology:The seeds are lanceolate, the testa is prolonged at the apex into a slender thread-like awn which terminates into a plume of silky hairs. The entire length including the awn is cmActive constituents:K-strophanthoside, K-strophanthin-B and cymarin glycosides and Ouabain (G-strophanthin)Uses: it resemble digitalis in its effect, cardiotonic, diuretic, raise the blood pressure and it is not cumulative drug.Chemical tests:1- With 66% H2SO4 → emerald green2- With FeCl3 + H2SO4 → red colour → green colour.
93- Squill BulbOrigin: the sliced and dried scale leaves from the bulb of Urginea maritime F. Liliaceae.Active constituents: cardiac glycosides of bufadienolide type: scillarene A and scillarene BUses: 1- cardiotonic like digitalis.2- expectorant and used in chronic bronchitis.N.B. red squill is a variety of squill contains also anthocyanin dissolved in the cell sap, it is toxic and used only as rat poison.