Standardized Common
Name: Gentian
Other Common Names: Bitter Root, Yellow
Gentian
Family: Gentianaceae
Taxonomy: Gentiana includes over 350 mostly Asian species of herbs, which
are often bitter and medicinal. Gentiana lutea ranges from western
Europe into Turkey. It is classified with other species in Sect. Gentiana,
but its floral characters are unique, separating it from all other members of
the genus. Hybridization with related species is known but uncommon.
Description: Perennial herb with
vertical rhizome and long taproots. Rhizome branched or unbranched, with
ring-shaped stem scars, often with fibrous remains of leaf bases on upper
portion. Roots to 0.5(–1) m long, (0.5–)1–2.5(–4) cm in diameter,
longitudinally wrinkled. Stem 0.5–1.5 m high, thick, unbranched. Leaves in
basal rosettes and opposite; basal and lower cauline leaves petiolate with
short thick petioles, upper leaves often sessile with somewhat clasping bases;
lower leaves largest, 7–20(–30) cm long, elliptical to lanceolate or ovate,
yellowish-green, glaucous; base tapering; apex acute to obtuse; underside with
5–7 prominent parallel veins. Inflorescences axillary and terminal, cymose.
Calyx tubular, 10–15 mm long, irregularly (2–)5-toothed, split down one side;
corolla to >5 cm in diameter, star-shaped with short tube and 5(–9) long
spreading lobes, yellow to orange-yellow, often with brown spots, or rarely
red; stamens as many as corolla lobes, filaments fused basally to corolla and
sometimes fused into a tube, anthers elongated; ovary 1-locular, style 10–15 mm
long, stigmas 2. Fruit an ovoid capsule, 20–25 mm long; seeds numerous, brown.
Parts
in Commerce:
Rhizome and roots, dried slowly
Identification:
- (0.5–)1–2.5(–4)
cm in diameter, usually long but cut into segments of several cm before
drying; curved or bent, branching occasionally
- Outside brown to
yellowish brown; bark brownish to yellowish or reddish brown, rather
thick; central portion inside yellowish or orange-brown (white when fresh;
presence of orange color indicates properly prolonged drying)
- Upper portion
(rhizome) has ring-shaped scars; crown at top is thickened (sometimes to 8
cm in diameter) and bears scaly remains of leaf bases
- Roots have deep
longitudinal wrinkles that sometimes curve around root giving a twisted
appearance
- Almost
cylindrical in general shape, slightly flattened, but very irregular in
cross-section due to wrinkles
- Fracture tough
and pliable, becoming brittle when thoroughly dry
- Root
cross-section shows narrow cork layer, typically 4–6 cells thick; broad
ring of parenchyma (pericycle); narrow ring of phloem; conspicuous dark
brown layer of cambium cells; large xylem region consisting mostly of
parenchyma with few large vessels, not clearly radiate (more radiate near
cambium)
- Rhizome
cross-section shows cork layer containing collenchyma; cortex; phloem;
cambium; xylem (appearing weakly radiate outside, near cambium, but less
so near pith); central pith
- Odor unpleasant,
heavy, sweet, characteristic
- Taste initially
sweet, then strongly bitter
Adulterants: Several other
species of Gentiana may be found as substitutes; all contain similar
bitter principles and have been used medicinally in their own right. The
European species G. purpurea L., G. punctata L., and G.
pannonica Scop., which have been most commonly found in European material,
are all classified with G. lutea in Sect. Gentiana, but all have
smaller roots and rhizomes. If G. lutea is to be collected after three
years’ growth, as is desirable, the larger portions of the rhizomes ought to be
at least 2 cm in diameter. The crowns of G. purpurea often produce 8–10
stems, giving a highly branched appearance to the upper end of the rhizome,
whereas G. lutea produces only 1–4 stems; the rhizomes of G.
pannonica are said to have few ring-shaped wrinkles.
Veratrum album L. (Liliaceae or
Melanthiaceae), which is poisonous, appears similar to gentian before
flowering, although the leaves are alternate rather than opposite. Several
illnesses due to accidental use of Veratrum in homemade gentian wine
have been reported in recent years, and historical literature mentions it as a
contaminant in commercial gentian. The roots are easily differentiated from
those of gentian: they are whitish inside and have a conspicuous endodermis
enclosing the central vascular tissue, which contains very large xylem vessels
alternating with phloem patches. The outer portion of the cortex contains
irregular air spaces.
References:
Evans WC. Trease and Evans’ Pharmacognosy, 14th ed. London: WB Saunders
Company Ltd.; 1996:322–323.
Ho
T-N, and Liu S-W. A Worldwide Monograph of Gentiana. Beijing: Science
Press; 2001.
Tutin
TG. Gentiana. In: Tutin TG, Heywood VH, Burges NA, et al., eds. Flora
Europaea. Vol. 3. Cambridge: Cambridge University Press; 1972:59–63.
Wichtl M, ed. Herbal Drugs and
Phytopharmaceuticals, 3rd English
ed. Stuttgart: medpharm Scientific Publishers and Boca Raton, FL: CRC Press;
2004:248–250.
Youngken HW. Text-Book of Pharmacognosy, 5th ed. Philadelphia, PA: The
Blakiston Company; 1943:678–683
and 171–175.
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