English common name is alder buckthorn bark from mother plant Rhamnus frangula
Contains hydroxyanthracene derivatives (6,8-O-diglycosides of frangula-emodin: glucofrangulin A and B; 6-O-monoglycosides [rhamnoside and apioside of frangula-emodin] frangulin A and B; aglycone: frangula-emodin).
Used as a stimulant laxative for short-term treatment of occasional constipation.\n\nNote: It can only be used after one year of storage or after heating for at least 1 hour at 100 °C. This process oxidizes the reduced forms of anthraglycosides, which would otherwise cause excessively harsh effects.
It is the dried bark or its fragments from trunks and branches. Usually in short, tubular pieces with a grayish-brown, wrinkled outer surface and an orange-brown to red-brown inner surface. The fracture is short and fibrous on the inside.
The drug is listed in the pharmacopoeia.
In pulverized drug under the microscope we can see:
Periderm with multi-layered red cork
Collenchyma
Phloem fibers with chambers containing prismatic oxalate crystals
