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Inhibition of
Staphylococcus aureus
by
Osmorhiza longistylis
Root Extracts
Jason N. Herold, Jennifer Antisdel,
Bernadette Corbett, Del Stallwood
Metropolitan Community College
Omaha Nebraska
Osmorhiza longistylis
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Smooth Sweet Cicely
Anise-scented
Habitat: moist woods
Plant Height: 30-90
cm
Flower Color: white
Blooms: May-June
Native
Source: USDA
Native American Uses
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Omaha
Poultice of pounded root applied to
boils.
Winnebago
Poultice of pounded root applied to
wounds.
Gilmore, M. R. 1919 Uses of Plants used by the Indians of
the Missouri River Region. SI-BAE Annual Report #33
(p.107)
Preparation of the Extracts
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Roots, stems and leaves separated
Plant material washed with distilled
water, then blotted dry
Plant material ground in Waring Blender
in 95% ethanol
Plant material filtered off and discarded
Ethanol distilled off, leaving an aqueous
sample
Preparation of Extracts
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Aqueous samples extracted with
methylene chloride
Dried with anhydrous sodium sulfate
Liquid decanted into round bottomed
flask
Methylene chloride removed by
distillation
Diffusion Disk Method
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24 hour cultures of S. aureus plated on
brain heart agar
100 micrograms extract reconstituted in
20 microliters of DMSO and pipetted
onto filter paper disks
Disks placed on plates and incubated
for 24 hours at 37°C
Zones of inhibition measured and
compared w/DMSO controls
Results
Root Extract
Broth Dilution Method
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24 hour Brain-Heart Broth cultures
100 micrograms of plant extract with 20
microliters DMSO incubated with 180
microliters of S. aureus culture for 2
and 24 hours at 37°C
Incubation mixtures diluted 10,000-fold
and 1,000,000-fold and spread plates
prepared with 100 microliters of S.
aureus
Results
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Stem and leaf extracts did not inhibit
growth when compared to DMSO
control
Root extracts inhibited growth by
12.2% and 25% when incubated for 2
and 24 hours, respectively
Results
Mean Inhibition Compared To DMSO Control
25
20
15
2 Hour
% Inhibition
10
24 Hour
5
0
Root
Stem
Leaf
Future Plans
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Dose-response curve of root extracts
Fractionate root extract using HPLC and
assay fractions for antibacterial activity
Isolate and Identify active ingredient
Acknowledgment
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Paul Evans collected the plants used in
this study