title: Antibacterial effect of silver (I) carbohydrate complexes on oral pathogenic key species in vitro.
abstract: BACKGROUND
  It was the aim of this study to evaluate the antibacterial impact of two silver(I) carbohydrate complexes with tripodal thioglycosides, namely tris[2-(β-D-thio-glucopyranosyl)ethyl]-amine-silver(I)-nitrate (3) and tris[2-(α-D-thio-manno-pyranosyl)ethyl]-amine-silver(I)-nitrate (4), on five oral pathogenic bacterial strains. Furthermore, cytocompatibility was tested using human gingival fibroblasts (HGF).
  
  
  METHODS
  Minimum inhibitory concentrations (MIC) were determined on five oral pathogenic bacterial strains by using the broth microdilution method: Fusobacterium nucleatum (ATCC 10953), Aggregatibacter actinomycetemcomitans (ATCC 33384), Porphyromonas gingivalis (ATCC 33277), Streptococcus mutans (ATCC 25175) and Enterococcus faecalis (DSMZ 20376). Furthermore, antimicrobial efficiency was tested using agar diffusion assays. To evaluate cytocompatibility, human gingival fibroblasts (HGFs) were exposed to AgNO3 and complex 3 followed by a live/dead staining.
  
  
  RESULTS
  MIC of the silver(I) complexes ranged between 0.625 and 5.0 mmol/L. The silver complexes 3 and 4 showed higher antibacterial efficiency against all tested species than AgNO3. Antibacterial efficiency of complexes 3 and 4 on F. nucleatum (≥18 mm) and A. actinomycetemcomitans (≥23 mm) was more pronounced than against P. gingivalis (≥15 mm). Complex 3 (20 mM) induced the largest inhibition zones (30 to 31 mm) on Gram-negative strains. For Gram-positive strains, the largest inhibition zones were achieved by complex 3 (20 mM/S. mutans: 28 mm, E. faecalis: 18 mm). Complex 3 had a lower cytotoxic impact on HGFs compared to AgNO3 by the power of ten.
  
  
  CONCLUSIONS
  The findings suggest that silver(I) carbohydrate complexes 3 and 4 might function as novel antimicrobial agents for the treatment of periodontal, carious or endodontic diseases.
authors.affiliation: Department of Conservative Dentistry and Periodontology, Jena University Hospital, An der Alten Post 4, 07743, Jena, Germany. markusreise@gmail.com.
authors.forename: Markus
authors.initials: M
authors.lastname: Reise
authors.affiliation: Laboratory of Organic and Macromolecular Chemistry, Friedrich Schiller University Jena, Humboldtstr. 10, 07743, Jena, Germany.|Jena Center for Soft Matter (JCSM), Philosophenweg 7, 07743, Jena, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Gottschaldt
authors.affiliation: Department of Conservative Dentistry and Periodontology, Jena University Hospital, An der Alten Post 4, 07743, Jena, Germany.
authors.forename: Carina
authors.initials: C
authors.lastname: Matz
authors.affiliation: Department of Conservative Dentistry and Periodontology, Jena University Hospital, An der Alten Post 4, 07743, Jena, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Völpel
authors.affiliation: Jena Center for Soft Matter (JCSM), Philosophenweg 7, 07743, Jena, Germany.|Chair of Materials Science, Otto Schott Institute for Materials Research, Friedrich-Schiller-University Jena, Fraunhoferstraße 6, 07743, Jena, Germany.
authors.forename: Klaus D
authors.initials: KD
authors.lastname: Jandt
authors.affiliation: Laboratory of Organic and Macromolecular Chemistry, Friedrich Schiller University Jena, Humboldtstr. 10, 07743, Jena, Germany.|Jena Center for Soft Matter (JCSM), Philosophenweg 7, 07743, Jena, Germany.
authors.forename: Ulrich S
authors.initials: US
authors.lastname: Schubert
authors.affiliation: Department of Conservative Dentistry and Periodontology, Jena University Hospital, An der Alten Post 4, 07743, Jena, Germany.
authors.forename: Bernd W
authors.initials: BW
authors.lastname: Sigusch
mesh_terms: D016976:Aggregatibacter actinomycetemcomitans / Q000187:drug effects; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002241:Carbohydrates / Q000494:pharmacology*; D002478:Cells, Cultured; D013293:Enterococcus faecalis / Q000187:drug effects; D005347:Fibroblasts / Q000187:drug effects; D016967:Fusobacterium nucleatum / Q000187:drug effects; D005881:Gingiva / Q000166:cytology; D006801:Humans; D008826:Microbial Sensitivity Tests; D016966:Porphyromonas gingivalis / Q000187:drug effects; D012834:Silver / Q000494:pharmacology*; D013295:Streptococcus mutans / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D002241:Carbohydrates; D012834:Silver
keywords: Antibacterial efficiency; Fibroblasts; Silver complexes; Silver nitrate