Rumex japonicus Houtt.: A phytochemical, pharmacological, and pharmacokinetic review

Rumex japonicus Houtt. (RJH-Yang Ti) RJH has been used as a folk medicine in East Asian countries for thousands of years. It has a wide range of therapeutic effects in terms of anti-microorganic, anti-oxidant, anti-inflammatory, and antitumor effects. Therefore, it is urgent to thoroughly review the existing knowledge for this herb from phytochemical, pharmacological, and pharmacokinetic perspectives. "Yang Ti" and its English, botanical and pharmaceutical names used as keywords to perform database search which included the Encyclopaedia of traditional Chinese Medicines, PubMed, EMBASE, AMED, CINAHL, Cochrane Library, MEDLINE, Science Direct, Scopus, Web of Science, and China Network Knowledge Infrastructure. Forty-five compounds identified from RJH. Besides, the therapeutic effects of RJH have been summarized as well. The root of RJH contains derivatives of anthraquinones, phytosterols, nepodin, oxanthrone c-glycosides, phenolic acid, cinnamic acid, flavonoid, epoxynaphthoquinol, triterpenoids, methoxynaphthalene, trihydroxybenzene, anthracene-9,10-dione, and other compounds. The extract of RJH and its chemical compounds showed the potentials as a complementary agent to exert antioxidant, antimicrobial, antisepsis, anticancer, anti-haematological disease, anti-dermatological disease, and antidiabetic activities. For the record, there is no study conducted on RJH regarding its pharmacokinetic aspect. Notably, Emodin may require additional attention due to its multiple organ toxicity concerns.