Acidity and polarity of five anthraquinones in rhubarb

Acidity and polarity arrangement of five anthraquinones in rhubarb: acidity: rhein >; Emodin > aloe-emodin > emodin methyl ether ≈ chrysophanol; Polarity: rhein >; Emodin > aloe-emodin > emodin methyl ether > chrysophanol

First, the growth habits of rhubarb

Like cold climate, cold tolerance, avoid high temperature. Wild in the mountainous areas of northwest and southwest China at an altitude of about 2000 meters; Most species are distributed in areas above 1400m, with the lowest temperature below-10℃ in winter and below 30℃ in summer. The frost-free period is 150- 180 days, and the annual rainfall is about 500-100.

Rhubarb is strict with soil. Generally speaking, loam or sandy loam with deep soil layer, rich humus and good drainage is the best, and sticky acid soil and low-lying stagnant water areas are not suitable for planting.

Second, the preservation method of rhubarb

Put it in a ventilated and dry place to prevent mildew and moth-eaten; Cooked rhubarb and wine rhubarb are sealed and placed in a ventilated and dry place.

Third, the distribution area of rhubarb

1. Rheum palmatum: distributed in western Sichuan, northwestern Yunnan, eastern Tibet, Shaanxi, southeastern Gansu and Qinghai.

2. Rheum tanguticum: distributed in Sichuan, northeastern Tibet, Gansu and Qinghai.

3. Medicinal rhubarb: distributed in western Henan, western Hubei, Guizhou, Sichuan and southwestern Yunnan.

Processing method of rhubarb

1, rhubarb

Remove impurities from raw materials, divide them into large and small blocks, wash them, fully wet them, cut them into thick blocks or small squares, and dry them in the air or at low temperature.

2, wine rhubarb

Mix rhubarb slices with yellow wine, fully moisten them, put them in a pot, heat them with slow fire, fry them dry, take them out and let them cool. Each piece of yellow film 100 kg, yellow wine 100kg. After the wine is decocted, the strength is slightly slower, which can induce the medicine to rush up and clear the excess heat.

3. Boil rhubarb with wine

Mix slices or pieces of rhubarb with yellow wine, slightly stuffy, put them in a stew pot or a suitable container, stew or steam until the inside and outside are black, and take them out to dry. Yellow pieces or pieces per piece 100kg, yellow wine 30kg.

4. rhubarb charcoal

Put the rhubarb slices in the pot, heat them with strong fire, fry them until the surface is black and the inside is brown, spray a little water to extinguish the sparks, take them out and let them cool thoroughly.

5, vinegar rhubarb

Slice rhubarb, mix well with rice vinegar, fully moisten it, put it in a pot, heat it with slow fire, fry it dry, take it out and let it cool. Each piece of yellow film 100kg, rice vinegar 15kg.

6, honey rhubarb

First, put the honey in a pot, heat it until it boils, add the yellow slices, stir-fry them with slow fire until they don't stick to your hands, take them out and let them cool. Each piece of yellow film 100kg, refined honey 18kg.