Genus Caralluma in Yemen: A Comprehensive Review of Taxonomy, Ethnomedicine, Phytochemistry, and Biological Activities

Abstract

This review provides up-to-date and comprehensive information on Caralluma species native to Yemen, linking traditional uses, taxonomy, phytochemistry, biological activities, and toxicology to guide future research. From over 300 scientific database sources, it identifies approximately 25 Caralluma species across Yemen's diverse landscapes, many endemics, with species like Caralluma dolichocarpa, Caralluma chrysostephana, and Caralluma eremastrum classified as endangered. In Yemen and other Asian regions, Caralluma is traditionally used to manage diabetes, gastrointestinal disorders, inflammation, leprosy, obesity, and arthritis. Key phytochemicals, including pregnane-type steroidal aglycones and glycosides, flavone glycosides, megastigmane glycosides, and triterpenes, which support its medicinal properties. in addition to flavone glycosides, megastigmane glycosides, bitter principles, and triterpenes. Pharmacological studies of Yemeni Caralluma extracts and isolated compounds demonstrated notable antibacterial, antioxidant, anticancer, and antidiabetic, and anti-inflammatory activities in both in vitro and in vivo models. These biological activities could be attributed to the occurrence of specific chemical classes in Caralluma genus. The review highlights the urgent need for further research on the conservation of endemic species and for the scientific validation of traditional uses, positioning Caralluma as a valuable resource for future drug discovery and ethnopharmacological studies in Yemen.

Keywords: Caralluma; biological activity; ethnopharmacology; phytochemistry; taxonomy.