Xanthium strumarium - a potential cheap resource of plant substances for medicinal use

Xanthium strumarium L. (Asteraceae) is an annual herb which reproduces solely by seed. So far its centre of origin was considered Central or South America. Recent archeological research revealed that the burs of X. strumarium were used in Yuergou site (400-200 cal BC) in the Turpan Basin of northwestern China. This plant adventive to Europe reduces germination of various crops and behaves like and aggressive invasive species. X. strumarium is the most frequently recorded plant in the field borders between the crop land and adjacent territories the agricultural areas in Bulgaria. We aim of this study is to reveal the potential of X. strumarium as a cheap source of compounds with valuable pharmacological activities. Here we analyse: 1) the traditional ethnobotanical data from its native habitats; 2) the modern investigations of pharmacological activity and essential secondary compounds. Traditionally the plant is used as febrifuge drug and an immunostimulant, as a diaphoretic agent and against malaria, as well as dysentry cure, astringent, sedative, analgesic, diuretic, against leucorrhoea and urinary diseases, eczema and skin disease, bleeding, insect bite, to treat boils and pimples, against smallpox and stomach diseases, earache and strumous disease, leprosy, headache, fever, etc. X. strumarium contains sesquiterpene lactones, thiazinediones, phenolic acids etc. and posses anticancer, antitussive, antifungal, antiinflammatory, antinociceptive, hypoglycaemic, antioxidant, antitrypanosomal, and antidepressant-like activity, diuretic effects, insecticidal and herbicidal activities as well as antitrypanosomal effect. A pharmaceutical application of this plant in the future would reduce its populations and thus would contribute to the biodiversity conservation.