title: Echinacea purpurea supplementation stimulates select groups of human gastrointestinal tract microbiota.
abstract: OBJECTIVE
  The objective of this research was to determine the effects of the dietary supplement Echinacea purpurea on aerobic and anaerobic bacteria common to the human gastrointestinal (GI) tract. Botanical extracts have shown in vitro antimicrobial effects against certain pathogenic bacteria. It is uncertain if medicinal herbs have any effect against pathogenic bacteria or on the native GI microbiota.
  
  
  METHODS
  Fifteen human subjects consumed 1000 mg of standardized E. purpurea for 10 days. Faecal samples were collected at baseline, 10 days and 17-18 days following supplementation. Samples were tested for select aerobic and anaerobic bacteria using plate culture microbiological methods.
  
  
  CONCLUSIONS
  Significant increases were found for total aerobic bacteria, Bacteroides group and Bacteroides fragilis after E. purpurea exposure. Supplementation did not significantly alter the number of enteric bacteria, enterococci, lactobacilli, bifidobacteria or total anaerobic bacteria.
  
  
  CONCLUSIONS
  Echinacea supplementation has altered the GI microbiota. The health consequences associated with this change are unknown but previous research has shown increased Bacteroides concentrations associated with diarrhoea, inflammatory bowel disease and increased risk of colon cancer. Additional research should delineate the role of Echinacea in the stimulation of Bacteroides and describe the effects of other botanical supplements to the GI microbiota.
authors.affiliation: Food Science and Human Environmental Sciences, Department of Human Environmental Sciences, University of Arkansas, Fayetteville, AR 72701, USA. llhill@uark.edu
authors.forename: L L
authors.initials: LL
authors.lastname: Hill
authors.forename: J C
authors.initials: JC
authors.lastname: Foote
authors.forename: B D
authors.initials: BD
authors.lastname: Erickson
authors.forename: C E
authors.initials: CE
authors.lastname: Cerniglia
authors.forename: G S
authors.initials: GS
authors.lastname: Denny
mesh_terms: D000328:Adult; D015169:Colony Count, Microbial; D019587:Dietary Supplements; D020900:Echinacea; D005260:Female; D041981:Gastrointestinal Tract / Q000382:microbiology*; D006801:Humans; D008297:Male