Rehmannia from Jili District

Rehmannia from Jili District

　　【Also known as】Flask flower, mountain tobacco, mountain cabbage.

【Source】The tuberous root of Rehmannia glutinosa Libosch, a plant of the Scrophulariaceae family.

【Plant morphology】A perennial herb with white long soft hairs and glandular hairs all over the plant. Leaves grow in basal tufts, obovate-lanceolate, with the base gradually narrowing into a petiole, margins irregularly blunt-toothed, leaf surface wrinkled, underside slightly purplish. Flower stems emerge from the leaf tufts, inflorescence racemose; calyx shallowly 5-lobed; corolla bell-shaped, slightly two-lipped, purplish-red, often with yellowish-purple stripes inside. Capsule spherical or ovoid, with persistent calyx and style. Flowers bloom from April to June, fruits from July to August. Grows on slopes, field ridges, and roadsides. Mainly produced in Henan, Liaoning, Hebei, Shandong, and Zhejiang; mostly cultivated.

【Harvesting and processing】Dig in autumn, remove the rhizome head and fibrous roots to obtain fresh Rehmannia; dry the roots until 80% dry and the interior turns black, then knead into lumps to make raw Rehmannia; steam raw Rehmannia until black and glossy to make prepared Rehmannia.

【Characteristics】Fresh Rehmannia is spindle-shaped or cylindrical, often constricted in the middle forming bead-like sections; surface pale orange with wrinkles, lenticels, and bud scars; fleshy, brittle, with yellowish-white cross-section and small orange-red dots in the cortex; taste slightly sweet and slightly bitter. Raw Rehmannia is irregularly lump-shaped; surface grayish-brown or dark brown, highly wrinkled; texture tough, cross-section dark brown, glossy, sticky; taste slightly sweet.

【Chemical components】Contains catalpol, various amino acids and sugars, mannitol, β-sitosterol, and campesterol, among others.

【Properties and flavor】Fresh Rehmannia is cold in nature, with sweet and bitter flavors. Raw Rehmannia is cold in nature, with a sweet flavor.

【Functions and indications】Fresh Rehmannia clears heat, promotes fluid production, cools blood, and stops bleeding; used for wind-heat injuring yin, red tongue with thirst, maculopapular rashes, vomiting blood, nosebleeds, sore throat. Raw Rehmannia clears heat, cools blood, nourishes yin, promotes fluid production; used for fever with thirst, maculopapular rashes, yin deficiency with internal heat, vomiting blood, nosebleeds, diabetes, and infectious hepatitis.