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Standardized Common
Name: Marshmallow
Family: Malvaceae
Taxonomy: Althaea
includes about a dozen species, mostly European or Asian. Althaea
officinalis is native to Europe, and is cultivated and sometimes
naturalized in the United States.
Description: Perennial herb, to
1.2(–2) m tall, sometimes with a thick horizontal rhizome; multiple stems
arising from a single rootstock, usually unbranched, the lower portions thick
and woody; upper stems softly pubescent with grayish stellate hairs. Leaves
alternate, ovate, softly pubescent with stellate hairs; base rounded to
subcordate; apex acute; margins irregularly serrate, sometimes palmately
3-lobed, with lobes incised not more than halfway to base; venation palmate.
Inflorescences mostly lateral, short-peduncled racemes, or terminal or flowers
solitary. Flowers with an outer whorl of 6–9 linear to lanceolate, sepal-like
bracts (epicalyx); sepals 5, ovate, curving over fruit; petals 5, pale pink,
15–20 mm long, obovate with notched apices; stamens numerous, the filaments
fused into tube around styles, the anthers purplish-red; gynoecium of numerous
fused carpels with separate styles. Fruit a whorl of mericarps, each 1-seeded,
smooth-surfaced, pubescent with stellate hairs.
Parts
in Commerce:
Roots, usually peeled of outer cork, often sliced or chopped into small pieces
Identification:
- Cylindrical or
slightly tapering, often spirally twisted, longitudinally furrowed, up to
about 20 cm long and 1–2 cm in diameter
- Outer cork, if
present, grayish to yellowish brown with numerous rootlet scars, fibrous,
easily peeled off in long strips
- Outer surface of
peeled roots whitish, finely fibrous; small brown rootlet scars may still
be visible
- Inner tissues
whitish, except for distinct brown to yellowish-brown or grayish cambial
lines, and starchy
- Fracture of bark
fibrous, of wood short and granular
- In
cross-section, has brown cork and periderm (if present); whitish ring of
cortex and secondary phloem with numerous narrow inconspicuous rays;
cambial line; large, whitish to slightly yellowish multiradiate xylem
- Rays more easily
seen, and large clear mucilage cells may be observed, when surface of
cross-section is moistened
- Odor weak,
aromatic
- Taste
mucilaginous, slightly sweet
Because
of its high mucilage content, A. officinalis has a swelling index of 10
or more, meaning that 1 gram of material mixed and allowed to stand in a
measure of water should expand into at least 10 cc of mucilage (see the
treatment of Psyllium for fuller explanation). The material must be ground to a
fine powder before such a test is performed. A simple chemical test can also be
performed by moistening a cut surface with a solution of sodium hydroxide
(lye); the mucilage cells produce a yellow color.
Adulterants: Substitution of
roots of Alcea rosea L. (Hollyhock), which has been previously placed in
Althaea and resembles A. officinalis, is reported. Fractured
surfaces are yellow; the fibers are coarser, and the texture may be harder.
References:
British Herbal Medicine
Association. British Herbal Pharmacopoeia. BHMA; 1996:129–130.
Evans WC. Trease and Evans’ Pharmacognosy, 14th ed. London: WB Saunders
Company Ltd.; 1996:216.
Greenish HG. Materia Medica. Jodhpur: Scientific Publishers (India); 1920
reprinted 1999:314–315.
Tutin TG. Althaea. In: Tutin TG, Heywood VH, Burges NA, et al.,
eds. Flora Europaea. Vol. 4. Cambridge: Cambridge University Press; 1976:253.
Wichtl M, ed. Herbal Drugs and Phytopharmaceuticals, 3rd English ed. Stuttgart:
medpharm Scientific Publishers and Boca Raton, FL: CRC Press; 2004:32–33.
World Health
Organization. WHO Monographs on Selected Medicinal Plants. Vol. 2. Geneva: World Health Organization;
1999–2002:5–11.
Youngken HW. Text-Book of Pharmacognosy, 5th ed. Philadelphia, PA: The
Blakiston Company; 1943:569–571.
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