Name: Dioscorea nipponska – Dioscorea nipponska
Dioscorea nipponica (Dioscorea nipponica); Dioscorea nipponica
A dioecious perennial herbaceous liana of the Dioscoreaceae family. It has a horizontal branched brownish-brown rhizome, from which thin, hard roots depart. The stem is twisted, simple, bare, up to 4-4.5 m long. Leaves alternate, short pubescent; the lower ones are 5-7-lobed, wide-heart-shaped, the upper ones are solid, triangular. The flowers are unisexual, small, yellowish-green, collected in simple spike-shaped inflorescences. The fruit is a box. Blooms in July – August.
Spread. Dioscorea nipponska occurs in thinned broad-leaved forests, on the edges of forests, on gentle slopes of mountains, along river valleys in the south of the Primorsky Krai. The plant is grown in the Far East.
Procurement and storage . Rhizomes are used for the manufacture of medicines, they are harvested from the end of April until late autumn. The excavated rhizomes are shaken off the ground, freed from stems and rotten parts, cut into pieces 7-8 cm long, washed in cold water and, after drying in the sun, dried in dryers at a temperature of 60-70°. The validity period is 1 year. The raw material goes to the production of the polysponin product, it is not sold by pharmacies.
Chemical composition . The rhizomes of this plant contain 6-8% saponins, the most important of which is the steroid dioscin.
Pharmacological properties and use . The plant-derived neogalenic product polysponin has pronounced antisclerotic properties. It reduces the amount of cholesterol in the blood, increases the lecithin/cholesterol ratio, which reduces the likelihood of cholesterol deposition in arterial vessels, lowers blood pressure, improves heart function, expands peripheral vessels, and increases diuresis. The main indication for the appointment of polysponin should be considered atherosclerosis (general, cerebral or coronary), especially if it is accompanied by hypertension or angina pectoris.
Medicinal forms and applications.
Internally – polysponin (Polysponinum) 1 tablet 2-3 times a day after meals. The course of treatment is 3—4 months in 20—30-day cycles, with breaks of 7—10 days between them. If necessary, the course of treatment is repeated after a 4-6 month break.