Effects of carbonization processing on quality control, chemical compositions, and pharmacological mechanism of Ganjiang (Zingiberis Rhizoma)

Ganjiang (Zingiberis Rhizoma, ZR) and Jiangtan (Carbonized Zingiberis Rhizoma, CZR) have long been used in traditional Chinese medicine (TCM) with a rich history in the treatment of various ailments. While ZR and CZR obviously stem from the same botanical source, their attributes, chemical compositions, pharmacological behaviors, and clinical applications are different owing to variations in the extent of drying and processing they undergo. In this paper, data pertaining to ZR and CZR were retrieved from databases including China National Knowledge Infrastructure (CNKI), PubMed, Web of Science, and Google Scholar. These sources were scrutinized to elucidate the distinctions between ZR and CZR arising from carbonization processing in terms of their ethnopharmacology, quality control, chemical compositions, biological activities, pharmacological mechanisms, and clinical uses. In this study, a total of 56 chemical constituents were identified and isolated from ZR and CZR, which primarily encompassed volatile oils, gingerols, and diphenylheptane compounds. CZR's pharmacological effects include hemostatic, anti-oxidant, analgesic, antibacterial, anti-cancer, and other biological activities. ZR has pungent and warm properties. It is a Yang-supplementing herbal medicine for ailments exacerbated by cold or damp climatic influences. CZR is a product of ZR after undergoing high temperature, with diminished intensity of its pungent and warm attributes. This change leads to a more gradual treatment efficacy, renowned hemostatic effects and its ability to gently invigorate the spleen and effectively alleviate diarrhea. Currently, research on the pharmacological mechanism of CZR is mainly focused on the effects of CZR on coagulation and fibrinolysis. Although the healing effect of CZR has long been known, and some correlation has been found between the changing composition and the changing color of the decoctions, people still lack relatively clear processing mechanisms to reflect the characteristics and specific quality standards of the ingredients of CZR's hemostatic effect. This review provides a systematic summary on quality control, chemical composition, ethnopharmacology, and pharmacology of CZR, offering novel perspectives for advancing the exploration of additional carbonized herbal medicine and fostering their application in clinical settings.