Phytochemistry and pharmacognosy of the genus Psorospermum

The genus Psorospermum Baker (tribe Vismieae, family Guttiferae, subfamily Hypericoideae) comprises 55 species, mainly of which are represented by shrubs or small trees typically growing in tropical regions of South America, Africa, and Madasgascar. Most of the species of the title genus have been used for centuries in the ethnomedical traditions of indigenous African populations as febrifugal, antidote against poisons, purgative, stomachic, and as a remedy for the treatment of leprosy, skin diseases (like dermatitis, scabies and eczemas), and subcutaneous wounds. Phytochemicals isolated from Psorospermum spp. comprise alkaloids, simple and prenylated anthraquinones, flavonoids, long chain alcohols and hydrocarbons, steroids, tannins, terpenes, and simple and prenylated xanthones. The reported biological activities of the above mentioned natural compounds refer to anti-bacterial, anti-protozoal, anti-fungal, anti-viral, anti-cancer, anti-oxidant, and neuroprotective effects. The aim of this review is to examine in detail from a phytochemical and pharmacologically points of view what is reported in the current literature about the properties of phytopreparations or individual active principles obtained from plants belonging to Psorospermum genus.