Historical and pharmacological studies on rehmannia root processing- Trends in usage and comparison of the immunostimulatory effects of its products with or without steam processing and pretreatment with liquor.

Ethnopharmacological Relevance: The dried root of Rehmannia glutinosa (RR) is a crude drug used in traditional Japanese Kampo medicine and traditional Chinese medicine (TCM). Sometimes, the crude drug is subjected to additional processing before use.

Aim Of The Study: To determine the effects of steam processing and pretreatment with liquor of RR through historical investigation, analytical chemistry, and pharmacological experiments.