Family: Hypericaceae
Genus: Hypericum
Species: perforatum
(i) General background on the plant
A group consisting of some 300 species of perennials and deciduous semi-evergreen or evergreen sub-shrubs and shrubs, chiefly of temperate and subtropical regions of the northern hemisphere. Its name, from the Greek hyper, above, and eikon, a picture, alludes to branches being placed, in a pagan festival above images to ward off evil spirits.
H. perforatum is an erect glabrous rhizomatous perennial, 30 - 90cm. Stems are woody at the base with two raised lines. Leaves are 1 - 2cm, sessile, elliptic oblong or linear and obtuse. Leaves are abundantly flourished with translucent glandular dots. The inflorescence is yellow, many-flowered, flowers being 2cm in diameter. Sepals are entire, lanceolate and glandular, being much shorter than the petals.
St John's Wort is common in open woods, hedgebanks and grassland and is common particularly on calcareous soils. It is widespread throughout most of the UK, Europe, West Asia, North Africa, Madeira and the Azores.
(ii) Details of quality characters
St John's Wort is a herb in use since ancient times as a remedy for anxiety and depression. It contains hypericin that inhibits monoamine oxidase, a bodily chemical associated with depression. Hypericin does not act alone, like many herbal medicines, St John's Wort relies on the complex interplay of many constituents for its antidepressant actions. Patients suffering from depression experience relief, increased appetite, more interest in life, greater self esteem and restoration of normal sleeping patterns. Trials have shown that St John's Wort extract compares favourably with standard prescriptive antidepressant drugs, including maprotiline hydrochloride, Prozac, diazepam, imipramine. Also in favour of St John's Wort is the absence of serious side-effects experienced by those taking it, relative to prescribed antidepressants.
Studies have also shown that St John's Wort supports the viral-inhibiting function of the immune system. In experiments with mice infected with the HIV virus, the progress of the virus was halted. This led to testing on human HIV and AIDS patients. The results are inconclusive, but anecdotal information reports a significant improvement in some patients.
(iii) Current production and yields
(iv) Constraints on production
Not fully hardy and will not do well in more Northern European regions.
(v) Markets and market potential
In Europe and especially Germany, St John's Wort is prescribed twice as often as standard antidepressants for depression. In May 1997 St John's Wort was featured in the American 'Newsweek' magazine, as at least 1 in every 20 Americans suffer from depression each year, the market potential is huge. It was also featured in the British Medical Journal "St John's Wort for Depression"in 1996.
St John's Wort also has application as a dye. The flowers yield a yellow dye when alum is used as the mordant, and an orange-red dye when tin is used as the mordant. The stalks yield a brown-red dye using alum as the mordant.
(vi) Other information
St John's Wort does not need any particular care, it is fully to half hardy. It needs sun or semi-shade and fertile soil that is not too dry. The species is propagated by by seed or division in autumn or spring. They are rather short-lived by nature, and when grown near the limits of its climatic tolerance may die apparently inexplicably. It is best harvested when it flowers. St John's Wort blooms from June to August, it is considered at its most potent on St John's Day June 24th, hence its name.
(vii) Contacts
National
Herb Centre, Banbury Road, Warmington, Near
Banbury, OX17 1DF, UK.
Tel: +44 (0) 1295 690999. Fax: +44 (0) 1295 690034
(viii) References
Clapham, A.R., Tutin, T.G. and Warburg, E.F. (1962). Flora of the British Isles. Cambridge University Press.
Zues, J. The Natural Prozac Programme: How to use St John's Wort, the Antidepressant Herb.
Bloomfield, H. Hypericum and Depression.
St John's Wort for Depression (August 3rd 1996). British Medical Journal 313, No 7052.