Native American tribes used various woodland and prairie plants for a number of years. They used the plants for food as-well-as for their medicinal purposes. In order to obtain the medicinal properties of the plants they could; grind them up to rub on a

1
Antibacterial Properties of Prairie Plants
Evan Blind, Sophie Gardner, Ingrid Jorud, Amanda
NiemannDepartment of Biology, Concordia College,
Moorhead, Minnesota 56562
Discussion The experiment was conducted in a
traditional manner to parallel the way plant
properties have historically been isolated and
used. This was done to maintain consistency in
methods and results. The properties that have
been shown according to past folklore were not
present within the constraints of the experiment
performed. Multiple variables from this
experiment could be altered for further research.
Changes may include testing different
concentrations of plant extracts, purification
for one characteristic, testing against different
strands of bacteria, or testing at different
growth stages. Errors may have changed results
or malfunctioned, such as insufficient
sterilization of equipment used, causing plate
contamination and growth other than the intended
bacteria. The plant extracts could have also
been contaminated by growth of microscopic
organisms on plant samples. Also, variation in
concentration and potency of plants may have
affected results. After analysis, it has been
shown that when tested against S. epidermidis and
E. coli, antibacterial properties were minimal
when prepared in the executed method. There were
slight zones of inhibition present when testing
Mountain Mint and Rose Hips against S.
epidermidis. There were no antibacterial effects
when tested against E. coli. Further testing
could be done to determine which part of the
bacterial growth was affected. Also, studies
could be done to isolate which part of the mint
and rose hips affected growth. This experiment
is preliminary and could lead to vast and further
research of unique characteristics, such as
analyzing mint oils or testing the effects of
plants on human systems.

Materials and methods The materials used for
this experiment included Echinacea root, Yarrow
leaf, Yarrow root, Milkweed pod, Milkweed root,
Sage, Mountain mint, Rosehips, half pint jars,
40 alcohol, paper filter disks, tweezers, coffee
filters, Bunsen burner, Petri plates, nutrient
agar, incubator, and E. coli and S. epidermidis
pure cultures. The first step in performing
the experiment was to gather samples of each
plant from the prairie. One half-pint canning
jar was filled with the appropriate part (root,
leaf, fruit, etc) of the specific plant. In the
lab, the plants were finely chopped and put back
into the jars along with sufficient 40 alcohol
to cover the chopped plant. They were incubated
at 30C for 10 days to allow for extraction of
the chemical properties of the plant. The
extractions were then strained with a coffee
filter to remove any solid particles. Two
types of bacteria, E. coli and Staphylococcus
epidermidis, were tested against each plant. For
both bacteria, two Petri plates for each plant
were labeled, filled with nutrient agar to cover
the bottom, and plated with the corresponding
bacteria. Three paper filter disks were soaked
in the liquid extractions and placed on each
plate. One control plate was also made for each
bacteria using three disks soaked in just 40
alcohol. The plates were then incubated at 35C.
After 3 days, the plates were removed, and
checked for any inhibition of bacterial growth.
For those that had an antibacterial effect, the
zone of inhibition was measured in millimeters.
Abstract In this experiment, the medicinal
properties of prairie plants were analyzed for
antibacterial effects in accordance with folklore
of natural plant treatments. Six plant species
found on the bluestem prairie were sampled,
including Echinacea, Rosehips, Mountain Mint,
Yarrow (leaf and root), Milkweed (pod and root),
and Sage. A 23 liquid alcohol extraction was
performed on the respective plants. After three
weeks, paper filter disks were soaked in the
extracts and plated on S. epidermidis and E.
coli. The plates were incubated at 35C and
observed over a period of three days. The
results showed that Mountain Mint and Rosehips
showed slight zones of inhibition on S.
epidermidis, while the remaining plants did not
seem to affect the bacteria.
Figure 2. As shown on this graph, there were
antibacterial properties expressed by Mountain
Mint and Rosehip fruit against S. epidermidis.
Zone of Inhibition Measurement (mm)
Introduction Native American tribes used various
woodland and prairie plants for a number of
years. They used the plants for food as-well-as
for their medicinal purposes. In order to obtain
the medicinal properties of the plants they
could grind them up to rub on a wound or make a
tea with the leaves/root and consume the tea.
Sometimes the medicine would be of
success, however, if it was not successful, the
people of the tribe would try some other means of
medicine. When a plant showed some signs of
promise, the plant would then be associated with
the sickness or strain it relieved. Today we
can not test random plant extracts or wraps on
people as they in the past did due to medical
ethics policies, but we can test for
antibacterial properties of plants in a lab. The
purpose of this experiment is to test
anti-bacterial traits of varying prairie plant
species. This experiment will test plants with a
folkloric history of exhibiting medicinal
properties. The plants will be selected and
tested for anti-bacterial chemicals in accordance
with speculated benefits. In this experiment
we will use two types of bacteria with different
cell wall configurations. Using extracts of the
selected plants we will test the possible
antibacterial effects against the chosen
bacteria.
Table 1. Displays the results that were
collected from the measurements of the zones of
inhibition on the Rosehips and Mountain Mint S.
epidermidis Petri plates.
Results In the experiment, there were slight
zones of inhibition for two species Rose Hips
and Mountain Mint. The zones of inhibition
occurred only on the S. epidermidis plates.
The Rose Hips sample exhibited zones of 3 and 4
mm in diameter. The Mountain Mint displayed 4
and 4 mm zones. No zones of inhibition formed
from the other six samples. There were no zones
of inhibition present on the E.coli plates.
A T-test was performed using our measurement of
zones of inhibition to determine if there was
significant difference between the observed
antibiotic properties. Since our ?tob?lt 2.13, it
can be concluded that there is no difference
between the observed properties. This would
not indicate what the antibacterial properties of
the plants were, only that antibacterial
properties were present.
Literature cited Blumenthal et al. The Complete
German Commission E Monographs Therapeutic Guide
to Herbal Medicines. Austin, Texas American
Botanical Council, 1998. Linde K et al. The
Methodological Quality of Randomized Controlled
Trials of Homeopathy, Herbal Medicines and
Acupuncture. Int J Epidemiol. 30.3 (2001)
526-531. Suffredini, I. B., Sader, H. S.,
Gonçalves, A. G., Reis, A. O., Gales, A. C.,
Varella, A. D., et al. (2004). Screening of
antibacterial extracts from plants native to the
Brazilian Amazon rainforest and Atlantic forest.
Brazilian Journal of Medical and Biological
Research, 37(3), 379-384. Tyler, Varro E. Herbs
of Choice The Therapeutic Use of
Phytomedicinals. Pharmaceutical Products Press
1994. Tyler, Varro E. The Honest Herbal A
Sensible Guide to the Use of Herbs and Related
Remedies. New York Pharmaceutical Products
Press An Imprint of the Haworth Press, Inc.,
1993. Yale, Steven H. MD, and Keijan Liu, PhD.
Echinacea purpurea Therapy for the Treatment of
the Common Cold A Randomized, Double-blind,
Placebo-Controlled Clinical Trial. Arch Intern
Med. 164.11 (2004) 1237-1241.

Acknowledgments We thank Colleen Hyde for the
preparation of the nutrient agar, provision of
isolated bacterial samples, and use of lab
equipment. Recognition is also given to Bluestem
Prairie for the reference of prairie plants.
Use of the microbiology incubators and lab area
was greatly appreciated.
Photo 1. Zones of inhibition can be faintly seen
in this photograph. The orange coloring is due
to staining of the agar by the extraction.
Figure 1. This shows that there were no
antibacterial properties expressed against E.
coli.