Inhibition of Staphylococcus aureus

by Osmorhiza longistylis

Root Extracts

Jason N. Herold, Jennifer Antisdel, Bernadette Corbett, Del Stallwood

Metropolitan Community CollegeOmaha Nebraska

Osmorhiza longistylis

Smooth Sweet Cicely Anise-scented Habitat: moist woods Plant Height: 30-90

cm Flower Color: white Blooms: May-June Native

Source: USDA

ITS

Native American Uses 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 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

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 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

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

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

0

5

10

15

20

25

% Inhibition

Root Stem Leaf

Mean Inhibition Compared To DMSO Control

2 Hour

24 Hour

Future Plans

Dose-response curve of root extracts

Fractionate root extract using HPLC and assay fractions for antibacterial activity

Isolate and Identify active ingredient

Acknowledgment

Paul Evans collected the plants used in this study