Hypericaceae (I)

The st. john’s-wort family (Hypericaceae) is a family of biennial herbaceous plants, shrubs and trees. The family occurs worldwide.

The family has an eventful history and is described differently by different taxonomists. Often, this family is not recognised: the plants are then added to the family Guttiferae or Clusiaceae.

Many members of this family contain the naphthodianthrone derivatives hypericin and pseudohypericin; these are found in glandular tissues that appear as black, orange or translucent spots or lines on petals, leaves and other parts of the plant. These compounds are photosensitive and can cause reactions in grazing animals, such as blistering of the snout, as well as in humans who come into prolonged contact with the plants. The highest concentration of these substances can be found in the common St John's wort (Hypericum perforatum), which is used in herbalism and as a folk remedy.

Hypericum (or St John's wort) is widespread with 370 species, mainly in the northern hemisphere. The name Hypericum is derived from the Greek 'Hyper' - above and 'Eikon' - picture, referring to the traditional hanging of the plants above religious pictures to ward off evil, when they were harvested on St John's (John the Baptist) day (24 June).