title: A comparison of the anti-Staphylococcus aureus activity of extracts from commonly used medicinal plants.
abstract: BACKGROUND
  Resurgences of Staphylococcus aureus infection continue globally, with antibiotic resistance increasing dramatically, making these infections more difficult to treat. S. aureus epidemics impose public health threats, and economic burdens on health care costs worldwide, presenting challenges modern medicine struggles to control.
  
  
  OBJECTIVE
  In order to answer today's call for effective treatments against S. aureus, we evaluated and compared various botanical extracts that have historically been suggested as useful for their antimicrobial properties against S. aureus.
  
  
  METHODS
  Briefly, S. aureus cultures were treated with selected botanical extracts and the minimum inhibitory concentration (MIC) determined. In addition, to obtain more quantitative measures on bacterial growth, 24-hour growth studies were done to examine the temporal activity and stability of various botanicals on bacterial replication.
  
  
  RESULTS
  The antimicrobial activity observed for the botanical extracts used in this comparative evaluation of efficacy included both bacteriostatic and bacteriocidal activity against S. aureus. Highly effective botanicals including Salvia officinalis, Eucalyptus globulus, Coleus forskohlii, Coptis chinensis, Turnera diffusa, and Larrea tridentata exhibited MIC values ranging from 60 to 300 μg/mL and a 10(6)-fold reduction in bacterial replication. Arctostaphylos uva-ursi and Allium sativum were slightly less effective, exhibiting MIC values ranging from 90 to 400 μg/mL and a 10(5)-fold reduction, while Anemopsis californica gave MIC value of 360 μg/mL and a 10(4)-fold reduction in bacterial replication. Many botanicals, especially at lower doses, had an initial inhibitory effect followed by a recovery in bacterial replication. Such botanicals included E. globulus, C. chinensis, T. diffusa, A. californica, and Berberis vulgaris.
  
  
  CONCLUSIONS
  Our data demonstrate that S. officinalis, E. globulus, C. forskohlii, A. uva-ursi, C. chinensis, T. diffusa, A. californica, A. sativum, and L. tridentata all show promising direct antimicrobial activity against S. aureus. For many of these botanicals, strong bacteriocidal activity was observed at higher concentrations, but even at lower concentrations, bacteriostatic activity was evident. Other botanicals including B. vulgaris, Baptisia tinctoria, and Glycyrrhiza glabra showed moderate activity against S. aureus, while Schisandra chinensis, Echinacea angustifolia, and Polygonum multiflorum were shown to be ineffective.
authors.affiliation: 1 Department of Naturopathic Research, Southwest College of Naturopathic Medicine , Tempe, AZ.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Snowden
authors.forename: Heather
authors.initials: H
authors.lastname: Harrington
authors.forename: Kira
authors.initials: K
authors.lastname: Morrill
authors.forename: LaDeana
authors.initials: L
authors.lastname: Jeane
authors.forename: Joan
authors.initials: J
authors.lastname: Garrity
authors.forename: Michael
authors.initials: M
authors.lastname: Orian
authors.forename: Eric
authors.initials: E
authors.lastname: Lopez
authors.forename: Saman
authors.initials: S
authors.lastname: Rezaie
authors.forename: Kelly
authors.initials: K
authors.lastname: Hassberger
authors.forename: Damilola
authors.initials: D
authors.lastname: Familoni
authors.forename: Jessica
authors.initials: J
authors.lastname: Moore
authors.forename: Kulveen
authors.initials: K
authors.lastname: Virdee
authors.forename: Leah
authors.initials: L
authors.lastname: Albornoz-Sanchez
authors.forename: Michael
authors.initials: M
authors.lastname: Walker
authors.forename: Jami
authors.initials: J
authors.lastname: Cavins
authors.forename: Tonyelle
authors.initials: T
authors.lastname: Russell
authors.forename: Emily
authors.initials: E
authors.lastname: Guse
authors.forename: Mary
authors.initials: M
authors.lastname: Reker
authors.forename: Onyria
authors.initials: O
authors.lastname: Tschudy
authors.forename: Jeremy
authors.initials: J
authors.lastname: Wolf
authors.forename: Teresa
authors.initials: T
authors.lastname: True
authors.forename: Oluchi
authors.initials: O
authors.lastname: Ukaegbu
authors.forename: Ezenwanyi
authors.initials: E
authors.lastname: Ahaghotu
authors.forename: Ana
authors.initials: A
authors.lastname: Jones
authors.forename: Sara
authors.initials: S
authors.lastname: Polanco
authors.forename: Yvan
authors.initials: Y
authors.lastname: Rochon
authors.forename: Robert
authors.initials: R
authors.lastname: Waters
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Langland
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D010936:Plant Extracts / Q000494:pharmacology*; D010946:Plants, Medicinal / Q000737:chemistry*; D013211:Staphylococcus aureus / Q000187:drug effects*
chemical_list: D000900:Anti-Bacterial Agents; D010936:Plant Extracts