Rhubarb PH103.14

Recap In the last class we learnt about Aloe contains dried juice obtained by Making incisions of the leave bases of Various species of Aloe. Belongs to the Family Liliaceae Contains Anthraquinone glycosides Used as strong purgative. PH103.14 3

Objectives On completion of this lesson, you would be able to know: The monograph of Rhubarb PH103.14

Rhubarb Synonym : Rheum, Rhizome-Rhei Rhubarb - Rhizome Biological Source : Peeled and dried roots and rhizomes of Rheum palmatum Rheum officinale Rheum emodi Rheum webbianum Family : Polygonaceae Fig.14.1 PH103.14

China, Tibet, Germany, India and other European Rhubarb Geographical Source : China, Tibet, Germany, India and other European Countries In India Kulu and Kulaman Kashmir Sikkim Assam PH103.14

Rhubarb Organoleptic characters: Colour : Brown to yellow Odour : Fragrant Taste : Bitter and Astrigent Size : 2 to 20 cm in length and 1.5 to 2 cm in diameter Shape : Sub-cylindrical, barrel-shaped, conical or in planoconvex pieces. Fig.14.2 PH103.14

Rhubarb Chemical Constituents : Contains Anthraquinone derivatives and their salts. Chrysophanol Aloe-emodin Rein Physicon Gallic acid Rhein acids Starch and Calcium oxalate PH103.14

Rhubarb Chemical tests : 1. With Ammonia, it acquires Pink colour. 2. With 5% Potassium hydroxide it gives Blood Red colour. 3. Under UV-radiation Rheum emodi gives Brown colour. 4. Borntrager’s test for Anthraquinone is positive with Rhubarb. PH103.14

Rhubarb Uses : Mild purgative Astringent In small doses it acts as Stomachic in Diarrhoea of children. PH103.14

Summary In this class we learnt about Rhubarb consists of peeled dried roots and rhizomes of Rheum palmatum, R. officinale, R. emodi and R.webbianum (Indian species) is belongs to the Family Polygonaceae Contains Anthraquinone derivatives as main chemical constituents Used as mild purgative. PH103.14

Quiz 1. Rhubarb belongs to the family Polygonaceae Leguminosae Solanaceae Umbelliferae PH103.14

Quiz 2. Rhubarb is used as Antipyretic Carminative Mild purgative Anti-viral PH103.14

Quiz Rhubarb contains Alkaloids Glycosides Volatile oils Carbohydrates PH103.14

Frequently Asked Questions Give two examples for Laxatives. (Mar/Apr’2005) Mention the Biological Source, Active Chemical Constituents and Uses of Rhubarb. (September’2002) PH103.14