St.-Johns-Wort

(Hypericum), a genus of plants of the family Hypericaceae. They are perennial, or more rarely annual, herbs and low, shrubby plants with opposite, entire leaves. The flowers are primarily in paniculate or corymbose inflorescence; they have a pentamerous perianth, yellow petals, and many stamens The fruit is a pod. There are more than 300 species in the temperate and subtropical regions, mainly in the Mediterranean area, as well as in the mountains of the tropics. There are more than 50 species in the USSR. A widely distributed species is perforated St.-John’swort (H. perforatum), which has dotlike glands visible on the leaves. The dried surface parts of the Hypericum are used to make decoctions and infusions (they contain tannins and essential oils), which are applied internally as astringents and antiphlogistics for colitis; the substances are also rubbed on the gums and used for gargling in the case of gingivitis or stomatitis. The decoctions are also applied externally for burns, wounds, and skin diseases. The antibiotic novoimanin is obtained from St.-John’s-wort. Hypericum leaves are used to make St.-John’s-wort vodka. Some Hypericum species are toxic for sheep, horses, and other agricultural animals. Many species are grown as ornamentals.