Bioactivity and Synergistic Analyses of Plant Extracts

1
Bioactivity and Synergistic Analyses of Plant
Extracts

• Suzy Harvey
• Honors Summer Research-HSRP
• Sweet Briar College
• 2004

2
Keeping Track

• Natural Products Research
• Plant extracts
• Bacteria
• Cymbopogon flexuosus
• Background
• Current research
• Future plans

3
Natural Products Research

• Investigation of Plant Extracts
• Bioactivity
• Synergy

http//www.faculty.sbc.edu/jbeck/
4
Microbes

• Gram-negative bacteria
• Cell wall structure mainly lipopolysaccharides
• Cytoplasmic membrane
• Gram-positive bacteria
• Cell wall structure mainly peptidoglycan
• No outer membrane

http//www.apsnet.org/education/K-12PlantPathways/
TeachersGuide/Activities/DNA_Easy/text/Figure5.htm
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Microbes

• Bacillus subtilis
• Gram-positive
• Rod-shaped
• Non-pathogenic to
• Humans
• Animals
• Plants
• Bacitracin

http//www.itg.uiuc.edu/exhibits/iotw/2001-05-10/
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Microbes

• Staphylococcus aureus
• Gram-positive
• Spherical-shaped
• Pathogenic
• Skin infections
• Food poisoning
• Bloodstream infections
• Surgical wound infections
• Pneumonia

http//www.cellsalive.net/photos/
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Microbes

• Klebsiella pneumoniae
• Gram-negative
• Rod-shaped
• Pathogenic typically hospital-acquired
• Pneumonia
• Urinary tract infections
• Intra-abdominal infections

http//www.ac-orleans-tours.fr/svt/theme3/exprocar
yo.htm
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Cymbopogon flexuosus

• Habitat
• Tropics and subtropics
• Historical Medicinal Uses
• Acne, flatulence, insecticide, antiseptic
• Ionones, Vitamin A
• Recent Research
• J. Heimbegner (SBC, 04)
• Antimicrobial activity reported

http//www.surfbreeze.com/plants/lemongrass.jpg
Journal of Essential Oil Research, 2000, 12, (5),
639-649.
Heimbegner, J. Synergistic Bioactivity Testing of
Extracts from a Medicinal Herb of the United
States Virgin Islands, Sweet Briar College
Honors Thesis, 2004.
9
Cymbopogon flexuosus

• Jaimes Research
• Hexanes crude layer
• Partially fractionated
• S. aureus
• EtOAc crude layer
• Partially fractionated
• S. aureus
• B. subtilis

http//www.faculty.sbc.edu/jbeck/researchers/Summe
r20200320Members.htm
Heimbegner, J. Synergistic Bioactivity Testing of
Extracts from a Medicinal Herb of the United
States Virgin Islands, Sweet Briar College
Honors Thesis, 2004.
10
Cymbopogon flexuosus
1
3
4

• Compounds
• S-Limonene
• R-Limonene
• Geraniol
• Citral
• Myrcene
• R-Citronellal
• S-Citronellal

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7
6
5
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Cymbopogon flexuosus-Bioactivity
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Cymbopogon flexuosus-Bioactivity
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Cymbopogon flexuosus-Bioactivity
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Cymbopogon flexuosus-Bioactivity
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Cymbopogon flexuosus-Synergy
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Cymbopogon flexuosus-Synergy
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Citral
trans Neral
cis Geranial
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R S-Citronellal
R-Citronellal
S-Citronellal
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Future Research

• Further research
• Cymbopogon flexuosus
• Synthetic study

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Acknowledgements

• Funding through
• Sweet Briar Honors Summer Research Program
• Commonwealth Health Research Board
• Grant 17-04
• Dr. Beck
• Toni Thomas Co-Op Extension Agent, USVI
• Jaime Heimbegner
• Farzana Sekander and Lauren Martin

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The Debate

• Synergy
• Two common definitions
• 1 Drug synergism occurs when two drugs are
  combined, and the actions of one drug enhances or
  aids the actions of the other.
• OR
• 2 Drug synergism occurs when two drugs are
  combined, and the effect exceeds the sum of their
  individual effects.

Heimbegner, J. Synergistic Bioactivity Testing of
Extracts from a Medicinal Herb of the United
States Virgin Islands, Sweet Briar College
Honors Thesis, 2004.
22
Linear vs. Area
Circle Area     p r 2
http//www.1728.com/diamform.htm
http//www.med.unsw.edu.au/pathology-cds/Section_5
_5.htm