St John's Wort - Hypericum perforatum:
The plant is a low-growing (1-3 inches) perennial with small yellow flowers
which tend to bloom in early summer. The fuzzy appearance of the flower is
due to the many stamens of the flower.
The oil or alcohol extract of St. John's Wort is reddish purple in color.
It is not water soluble, but it is light-sensitive.
The plant grows readily in meadow conditions. A native of central Europe
which has naturalized itself to New England (if not other regions) in North
America. (There are around 25 species of this plant, most research has been
conducted on H. perferatum, with some on H. brasiliense.)
There do not appear to be any culinary uses for St. John's Wort. Using the
extract is recommended over using the plant as-is.
Medicinal Uses in Folklore:
Ointments would be used to treat wounds. Its antidepressant properties were
Scanning the Scientific Literature:
The antiviral and anti-oxidase active ingredients of St. John's Wort appear
to be hypericin and the structurally-related pseudohypericin.
Each seems to have its own pharmacodynamics,
with hypericin the most highly studied, and presumably the most
Hypericin is a naturally occurring
photosensitizer that exhibits potent antiviral activity in the presence of
light. While maintaining a good level of light is a potential problem in the body,
there is at least one clinical study underway investigating the effect
of hypericin on HIV in people with the AIDS virus. Hypericin may also have
beneficial effects against other viral agents, such as FLV, cytomegalovirus
(HCMV), parainfluenza virus, and certain types of herpes simplex viruses.
There is speculation that by using chemoluminescence in the bloodstream,
hypericin could be triggered to act photodynamically against viruses. Such
be triggered by the luciferin-luciferase reaction (which is how fireflies get
their flash). Perhaps exposure to proper wavelengths of light may also help.
Hypericin may also have a lipophilic ("fat-loving") mode of action,
potentially binding the lipid in viral membranes.
Hypericum extract is more than just hypericin/pseudohypericin, and has
been used clinically to treat depression. In Germany, it is marketed as an
anti-depressant. In one
study it yielded results far superior to that of a placebo. There was no
negative effect on cognitive function, nor on concentration or attention
abilities of the subjects. The antidepressive effect of hypericum
extract might be explained in part in terms of a mild monoamine oxidase
although the constituent hypericin itself does not act in this fashion.
It is still uncertain which component(s) of the plant produces the
anti-depressive effect, so the mode of action is still uncertain. The
anti-depressive effect initiates over a period of one to two months.
Hypericum extracts also apparently have some antimutagenic, anti-inflammatory,
and anti-staphylococcal activities.
Another ingredient of the oil extract, hyperforin, may have some
efficacy in wound healing.
Excessive consumption of these extracts can cause rashes if the individual
is exposed to strong light. Varro Tyler rates it a plus on probable safety.
On St. John's Eve, June 24th, these plants would be gathered and hung in windows
and by doors to ward off lightening and evil spirits.
- Cass, H., St. John's Wort: Nature's Blues Buster.
- Klimas, J. E., A Pocket Guide to the Common Wild Flowers of
- Tyler, V.E., The Honest Herbal.
- Tyler, V.E., Herbs of Choice.
- Lavie G. Mazur Y. Lavie D. Meruelo D.
The chemical and biological properties of hypericin--a compound with a
broad spectrum of biological activities [published erratum appears in Med
Res Rev 1995 May;15(3):259]. [Review]
Medicinal Research Reviews. 15(2):111-9, 1995 Mar.
- Staffeldt B. Kerb R. Brockmoller J. Ploch M. Roots I.
Pharmacokinetics of hypericin and pseudohypericin after oral intake of the
hypericum perforatum extract LI 160 in healthy volunteers.
Journal of Geriatric Psychiatry and Neurology. 7 Suppl 1:S47-53, 1994 Oct.
- Utsumi T. Okuma M. Utsumi T. Kanno T. Yasuda T. Kobuchi H.
Horton AA. Utsumi K.
Light-dependent inhibition of protein kinase C and superoxide generation
of neutrophils by hypericin, an antiretroviral agent.
Archives of Biochemistry and Biophysics. 316(1):493-7, 1995 Jan 10.
- Lavie G. Mazur Y. Lavie D. Prince AM. Pascual D. Liebes L.
Levin B. Meruelo D.
Hypericin as an inactivator of infectious viruses in blood components [see
comments]. Transfusion. 35(5):392-400, 1995 May.
- Barnard DL. Huffman JH. Morris JL. Wood SG. Hughes BG. Sidwell RW.
Evaluation of the antiviral activity of anthraquinones, anthrones and
anthraquinone derivatives against human cytomegalovirus.
Antiviral Research. 17(1):63-77, 1992 Jan.
- Andersen DO. Weber ND. Wood SG. Hughes BG. Murray BK. North JA.
In vitro virucidal activity of selected anthraquinones and anthraquinone
Antiviral Research. 16(2):185-96, 1991 Sep.
- Carpenter S. Fehr MJ. Kraus GA. Petrich JW.
Chemiluminescent activation of the antiviral activity of hypericin: a
Proceedings of the National Academy of Sciences of the United States of
America. 91(25):12273-7, 1994 Dec 6.
- Schmidt U. Sommer H.
[St. John's wort extract in the ambulatory therapy of depression.
Attention and reaction ability are preserved]. [German]
Fortschritte der Medizin. 111(19):339-42, 1993 Jul 10.
- Bladt S. Wagner H.
Inhibition of MAO by fractions and constituents of hypericum extract.
Journal of Geriatric Psychiatry and Neurology. 7 Suppl 1:S57-9, 1994 Oct.
- Vukovic-Gacic B. Simic D.
Identification of natural antimutagens with modulating effects on DNA
- Shipochliev T. Dimitrov A. Aleksandrova E.
[Anti-inflammatory action of a group of plant extracts]. [Bulgarian]
- Molochko VA. Lastochkina TM. Krylov IA. Brangulis KA.
[The antistaphylococcal properties of plant extracts in relation to their
prospective use as therapeutic and prophylactic formulations for the
- Maisenbacher P. Kovar KA.
Analysis and stability of Hyperici oleum.
Planta Medica. 58(4):351-4, 1992 Aug.
Photo from Henriette's Herbal
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Last Updated: March 7, 1999.
Last Updated: April 16, 1998.