Bitter Tangerine Seed, a traditional Chinese medicine, refers to the seeds or fruits of the leguminous plant Thoroughwort Vine. Bitter Tangerine Seed is highly toxic and is mainly used for treating pain, expelling toxins, eliminating stagnation, and killing parasites. It is commonly used to treat scabies, eczema, sores, carbuncles, abdominal pain, and pediatric malnutrition.
[Botanical Characteristics of Bitter Tangerine Seed]
Thoroughwort Vine, also known as Lesser Thoroughwort Vine, Poison Fish Vine, and Large Vine World.
A perennial climbing shrub with thick stems. The branches are cylindrical with black-green skin, and the young branches have sparse soft hairs.
Alternate compound leaves with odd-pinnate arrangement, measuring 30-50 centimeters in length. Each leaf consists of 13-17 leaflets, which are rectangular with lanceolate shape, approximately 8-14 centimeters long and 3-4 centimeters wide. The tips are blunt, the margins are entire, and the base is slightly blunt. The undersides are covered with rusty yellow soft hairs.
The axillary inflorescence is conical and measures 15-30 centimeters in length. 2-5 flowers cluster on the nodes of the inflorescence axis. The bracts are ovate and sparsely hairy. The calyx is bell-shaped with 5 lobes, which are triangular and light green with short pubescence. The corolla is butterfly-shaped with 5 purple-red petals. There are 10 stamens and 1 pistil, with the ovary superior and linear, and the style curved with a rounded stigma.
The fruit is thick, woody, and ovoid or rectangular with grayish-green color and spots. It contains 1-5 seeds, which are reddish-brown to dark brown. The flowering period is from March to April, and the fruiting period is from October to November.
It grows by streams, in sparse forests, and among shrubs. It is distributed in Sichuan, Yunnan, Fujian, Guangdong, Guangxi, Guizhou, and other regions.
[Medicinal Properties of Bitter Tangerine Seed]
Bitter Tangerine Seed is a dried seed, which is flat and slightly kidney-shaped. The seeds attached to both ends of the fruit are round on one side and flat on the other, while the seeds in the middle of the fruit are flat on both sides. They are approximately 4 centimeters long and 3 centimeters thick.
The surface is reddish-brown to dark brown with a glossy appearance, sometimes with a thin gray-white film. The hilum is located in the middle of the concave waist. There are 2 fleshy, horny cotyledons that are easily longitudinally split. There are irregular protuberances around the hilum, causing the cotyledons to split longitudinally and not be flat.
It has a faint aroma and a mild taste with a tingling sensation. It is considered of good quality if the skin is reddish-brown, large in size, and free from insect damage.
It is harvested after the fruits are ripe in October. The fruit skin is removed, and the seeds are dried.
