Example 1
As a general procedure, shikonin or a composition comprising shikonin or a derivative thereof is formulated in capsules, optionally in combination with lecithin (phospholipids, comprising primarily phosphatidylcholine) (e.g., at a shikonin-to-lecithin weight ratio of about 1:1). The shikonin or derivative thereof may be substantially pure (from a synthetic or natural source) or a part of an extract of a plant, such as Lithospermum erythrorhizon, Arnebia euchroma or another member of the borage family.
Using the above general procedure, an extract of purple gromwell (Lithospermum erythrorhizon) root (zicao) was prepared using an appropriate solvent, followed by spray drying and sieving, to obtain a purple powder. 175 mg of the powdered purple gromwell extract, containing about 30% shikonin and/or derivatives thereof, was placed with an equal weight of lecithin (Lipoid® PS P 20×, obtained from Lipoid GmbH) in Capsugel® delayed release (DR) capsules.
As an alternative to capsules, a syrup was prepared comprising lecithin and shikonin (95% purity) at a 5:1 lecithin:shikonin ratio, 44% alcohol as solvent, and honey.
Based on literature reports, toxicity of shikonin is not expected at dosages of less than 8 grams per day.
