title: Impact of humic acids on the colonic microbiome in healthy volunteers.
abstract: OBJECTIVE
  To test the effects of humic acids on innate microbial communities of the colon.
  
  
  METHODS
  We followed the effects of oral supplementation with humic acids (Activomin®) on concentrations and composition of colonic microbiome in 14 healthy volunteers for 45 d. 3 × 800 mg Activomin®were taken orally for 10 d followed by 3 × 400 mg for 35 d. Colonic microbiota were investigated using multicolor fluorescencein situhybridization (FISH) of Carnoy fixated and paraffin embedded stool cylinders. Two stool samples were collected a week prior to therapy and one stool sample on days 10, 31 and 45. Forty-one FISH probes representing different bacterial groups were used.
  
  
  RESULTS
  The sum concentration of colonic microbiota increased from 20% at day 10 to 30% by day 31 and remained stable until day 45 (32%) of humic acid supplementation (P< 0.001). The increase in the concentrations in each person was due to growth of preexisting groups. The individual microbial profile of the patients remained unchanged. Similarly, the bacterial diversity remained stable. Concentrations of 24 of the 35 substantial groups increased from 20% to 96%. Two bacterial groups detected with Bac303 (Bacteroides) and Myc657 (mycolic acid-containingActinomycetes) FISH probes decreased (P> 0.05). The others remained unaffected. Bacterial groups with initially marginal concentrations (< 0.1 × 109/mL) demonstrated no response to humic acids. The concentrations of pioneer groups ofBifidobacteriaceae,EnterobacteriaceaeandClostridium difficileincreased but the observed differences were statistically not significant.
  
  
  CONCLUSIONS
  Humic acids have a profound effect on healthy colonic microbiome and may be potentially interesting substances for the development of drugs that control the innate colonic microbiome.
authors.affiliation: Alexander Swidsinski, Vera Loening-Baucke, Christoph Gille, Anne Reißhauer, Onder Göktas, Laboratory for Molecular Genetics, Polymicrobial Infections and Biofilms, Department of Medicine, Section of Gastroenterology, Hepatology and Endocrinology, Charité Universitätsmedizin Berlin, 10098 Berlin, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Swidsinski
authors.affiliation: Alexander Swidsinski, Vera Loening-Baucke, Christoph Gille, Anne Reißhauer, Onder Göktas, Laboratory for Molecular Genetics, Polymicrobial Infections and Biofilms, Department of Medicine, Section of Gastroenterology, Hepatology and Endocrinology, Charité Universitätsmedizin Berlin, 10098 Berlin, Germany.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Dörffel
authors.affiliation: Alexander Swidsinski, Vera Loening-Baucke, Christoph Gille, Anne Reißhauer, Onder Göktas, Laboratory for Molecular Genetics, Polymicrobial Infections and Biofilms, Department of Medicine, Section of Gastroenterology, Hepatology and Endocrinology, Charité Universitätsmedizin Berlin, 10098 Berlin, Germany.
authors.forename: Vera
authors.initials: V
authors.lastname: Loening-Baucke
authors.affiliation: Alexander Swidsinski, Vera Loening-Baucke, Christoph Gille, Anne Reißhauer, Onder Göktas, Laboratory for Molecular Genetics, Polymicrobial Infections and Biofilms, Department of Medicine, Section of Gastroenterology, Hepatology and Endocrinology, Charité Universitätsmedizin Berlin, 10098 Berlin, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Gille
authors.affiliation: Alexander Swidsinski, Vera Loening-Baucke, Christoph Gille, Anne Reißhauer, Onder Göktas, Laboratory for Molecular Genetics, Polymicrobial Infections and Biofilms, Department of Medicine, Section of Gastroenterology, Hepatology and Endocrinology, Charité Universitätsmedizin Berlin, 10098 Berlin, Germany.
authors.forename: Anne
authors.initials: A
authors.lastname: Reißhauer
authors.affiliation: Alexander Swidsinski, Vera Loening-Baucke, Christoph Gille, Anne Reißhauer, Onder Göktas, Laboratory for Molecular Genetics, Polymicrobial Infections and Biofilms, Department of Medicine, Section of Gastroenterology, Hepatology and Endocrinology, Charité Universitätsmedizin Berlin, 10098 Berlin, Germany.
authors.forename: Onder
authors.initials: O
authors.lastname: Göktas
authors.affiliation: Alexander Swidsinski, Vera Loening-Baucke, Christoph Gille, Anne Reißhauer, Onder Göktas, Laboratory for Molecular Genetics, Polymicrobial Infections and Biofilms, Department of Medicine, Section of Gastroenterology, Hepatology and Endocrinology, Charité Universitätsmedizin Berlin, 10098 Berlin, Germany.
authors.forename: Monika
authors.initials: M
authors.lastname: Krüger
authors.affiliation: Alexander Swidsinski, Vera Loening-Baucke, Christoph Gille, Anne Reißhauer, Onder Göktas, Laboratory for Molecular Genetics, Polymicrobial Infections and Biofilms, Department of Medicine, Section of Gastroenterology, Hepatology and Endocrinology, Charité Universitätsmedizin Berlin, 10098 Berlin, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Neuhaus
authors.affiliation: Alexander Swidsinski, Vera Loening-Baucke, Christoph Gille, Anne Reißhauer, Onder Göktas, Laboratory for Molecular Genetics, Polymicrobial Infections and Biofilms, Department of Medicine, Section of Gastroenterology, Hepatology and Endocrinology, Charité Universitätsmedizin Berlin, 10098 Berlin, Germany.
authors.forename: Wieland
authors.initials: W
authors.lastname: Schrödl
mesh_terms: D000328:Adult; D015169:Colony Count, Microbial; D019587:Dietary Supplements; D005260:Female; D000069196:Gastrointestinal Microbiome / Q000187:drug effects* / Q000235:genetics / Q000502:physiology*; D064368:Healthy Volunteers; D006801:Humans; D006812:Humic Substances; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008875:Middle Aged; D055815:Young Adult
chemical_list: D006812:Humic Substances
keywords: Colonic bioreactor; Colonic microbiota; Fluorescence in situ hybridization; Healthy volunteers; Humic acids; Oral supplementation