Rationale for Manufacturing of Cut-Pressed Granules from Herbal Raw Material Rich in Essential Oil: An Example of Chamomile Flowers and Sweet Flag Rhizome

Background: Currently, there are at least 43 different dosage forms present on the Russian Federation pharmaceutical market. A novel, unique dosage form – cut-pressed granules (CPG) – was developed in order to improve manufacturing characteristics and, therefore, quality of herbal drug products released in tea bags. However, treatment conditions may result in decreased levels of active substances in some of the plants, especially those containing essential oil, which is prone to degradation. The aim of this study was to assess feasibility of CPG manufacturing from herbal raw material rich in essential oil. Materials and Methods: Different morphological groups of raw material from two commonly used medicinal plants, chamomile (Matricaria recutita L.) flowers and sweet flag (Acorus calamus L.) rhizome, were chosen as the objects of the study. Qualitative composition of lipophilic constituents in herbal raw materials and CPG was assessed using thin-layer chromatography. Essential oil content was determined by steam distillation. Results: The results confirmed equivalence of chromatographic profiles for the analyzed raw materials and CPG; thus, granulation didn’t affect qualitative composition of lipophilic components in chamomile flowers and sweet flag rhizome. The study also showed that the granulation process, in fact, promoted stability of the dosage form: during long-term storage the content of essential oil in all of the assessed cut-pressed granules was equivalent or higher than in corresponding herbal raw material. Conclusions: It can be concluded that Matricaria recutita L. flowers and Acorus calamus L. rhizome can be used as herbal raw material for CPG manufacturing.