Historical Ethnobotany and the Need to Study Medicinal

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Historical Ethnobotany
Hildegard of Bingen
1098 - 1179
Joseph Smith
1805 - 1844
Fertile Crescent
King Assurbanipal – 668-626 BCE
In his garden with Queen and Servants
Babylonian Medicine
Datura stramonium
Cannabis sativa
Mandrake – Atropa mandragora
Mandrake – Atropa mandragora
ca. 1474
Water lily – Nymphaea alba
Vitis vinifera var. Pinot Noir
Opium poppy – Papaver somniferum
Ergot – Claviceps purpurea
Fly agaric – Amanita muscaria
Amanita muscaria ornaments?
Sumerian
Headdress
Sun god Horus and Tuth-Shena
Urgent need to study medicinal plants
1. To rescue knowledge in imminent danger
of being lost
Inventory by WHO found 20,000 plant
species in use for medicine in 90 countries
Only 250 of those species are commonly used
or have been checked for main active
chemical compounds
Urgent need to study medicinal plants
2. The utility of plants in current therapy
There has been a rush to develop synthetic
medicines based on plant medicines, but
often the synthetic medicines don’t work
as well as the original plant medicines.
For example – quinine and malaria
Efficacy of Quinine
• Quinine is traditional and effective preventative of
malaria
• Synthetic preventatives such as chloroquine,
maloprim, and fansidar have largely replaced the
use of quinine
• Many strains of Plasmodium have developed
resistances to the synthetics and the synthetics are
more toxic. It is recommended that people do not
take fansidar for more than 3 months due to
potential liver damage.
Malaria Cycle
Anopheles freeborni mosquito – intermediate
host and vector for Plasmodium sp.
Historical distribution of Malaria
Red areas show countries with malaria today
One of the sources of Quinine –
Cinchona succirubra
Cinchona pubescens
Timeline of Quinine Use
• 1633, a Jesuit priest named Father Calancha described how
to use quinine bark to cure fevers
• 1645 Father Bartolome Tafur took some bark to Rome and
many of the clergy used it
• Cardinal John de Lugo wrote a pamphlet to be distributed
with the bark - use of the bark became so widespread that
in the papal conclave of 1655 no one died of malaria
• 1654 – English aware of use of quinine bark
• 1735, a French botanist named Joseph de Jussieu
journeyed to South America and found and described the
tree that is the source of the bark - he sent samples to
Sweden where in 1739, Carl Linneaus named the tree
genus Cinchona
Timeline of Quinine Use
• 20 to 40 species of Cinchona - the species are very
hard to tell apart and the species will hybridize, so
the exact number of species is unknown – mostly
understorey trees
• 1820 the French chemists Joseph Pelletier and
Joseph Caventou isolated the alkaloid quinine
from the bark and identified it was the active
ingredient in Peruvian bark
• 1861, an Australian named Charles Ledger
obtained seeds from an Aymara Indian named
Manuel Incra
• by 1930, the Dutch orchards in Java produced 22
million pounds of quinine, 97% of the world’s
market
Chemical structure of quinine
Properties of Quinine
• Quinine itself is an odorless white powder with an
extremely bitter taste
• It can be used to treat cardiac arrhythmias as well
as malaria - it is also used as a flavoring agent
• Quinine prevents malaria by suppressing
reproduction of the Plasmodium and also helps
prevent some of the fevers and pain associated
with malaria
Quinine fluoresces under UV light
Raymond Fosberg in the
field in 1948
Cinchona bark drying in the sun in
Ecuador, 1944
Turriabla, Costa Rica agricultural center
Urgent need to study medicinal plants
3. To find new molecular models in plants
Many times we can take a plant chemical and
modify it or make synthetic copies of it that
are very valuable to us.
Lippia dulcis – sweetener from
Pre-Columbian America
Hernandulcin
Lippia as a sweetener
• In Pre-Columbian America, several plants
of the genus Lippia were used as
sweeteners. (F. Verbenaceae – the
verbenas).
• In the 20th century, L. dulcis was
chemically analyzed and a new sweetener
was found, hernandulcin, that is 800 to 1000
times sweeter than sucrose.
Urgent need to study medicinal plants
4. The wide use of plants in folk medicine
One positive aspect of the use of medicinal plants is
their low cost compared to the high price of new
synthetic drugs that are totally inaccessible to the
vast majority of the world’s people. Another
benefit is that most medicinal plants don’t have
the kinds of harmful side effects seen with
synthetic drugs.
Diospyros lycioides – source of
chewing sticks in Namibia
Ceanothus americanus – Native
American chewing stick
Modern Chewing Sticks
• Most chewing stick
plants have a wide range
of antibacterial activity
against a number of
odontopathic bacterial
species, and many also
contained healing and/or
analgesic compounds
Bloodroot – Sanguinaria canadensis
Rhizome of Bloodroot
Bloodroot extracts to treat
dental plaque
• Bloodroot extracts have been identified as
potentially valuable in controlling plaque
• Blood root has many alkaloids, known as
sanguinaria alkaloids, and sanguinarine in
particular, is thought to be a potential problem
limiting the usefulness of blood root as a dental
medicine
• There is an indication that sanguinarine may
provoke glaucoma in predisposed humans and
cats.
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