Microbicidal efficacy of thiocyanate hydrogen peroxide after adding lactoperoxidase under saliva loading in the quantitative suspension test

A. Welk, P. Rudolph, Jens Kreth, Ch Schwahn, A. Kramer, H. Below

Research output: Contribution to journalArticle

9 Scopus citations


Objective: As shown in the quantitative suspension test adding lactoperoxidase to a thiocyanate (SCN -) hydrogen peroxide (H 2O 2) combination over the physiological saliva level has significant positive antimicrobial effects to a level of totally killing Streptococcus mutans, Streptococcus sanguinis, and Candida albicans. The aim of this study was to evaluate this positive effect under human saliva loading. Methods: The bactericidal and fungicidal effect of lactoperoxidase was evaluated in a quantitative suspension test by using two test mixtures of a 2.0% thiocyanate and 1.2% hydrogen peroxide solution, one without (Group A) and one with (Group B) lactoperoxidase under saliva loading. Following the quantitative suspension tests (EN-13727/EN-13624), the growth of surviving bacteria and fungi in a nutrient broth was measured. The exposure times were restricted to 1, 3, 5, and 15 min. All statistical analyses were carried out with SPSS 11.5. Results: In the quantitative suspension test, the combination of thiocyanate and hydrogen peroxide showed relatively low antimicrobial effectiveness on S. mutans, S. sanguinis, and C. albicans in the presence of human saliva at measured time points in comparison to the mixture with lactoperoxidase, which showed a high bactericidal activity within 15 min (S. mutans and S. sanguinis) and fungicidal activity within 3 min (C. albicans). Conclusion: The antimicrobial effectiveness of the tested thiocyanate hydrogen peroxide combination was increased significantly by adding lactoperoxidase in the quantitative suspension test under human saliva loading.

Original languageEnglish (US)
Pages (from-to)1576-1582
Number of pages7
JournalArchives of Oral Biology
Issue number12
Publication statusPublished - Dec 1 2011
Externally publishedYes



  • Candida albicans
  • Effectiveness
  • Lactoperoxidase-thiocyanate-hydrogen peroxide system
  • Quantitative suspension test
  • Saliva
  • Streptococcus mutans
  • Streptococcus sanguinis

ASJC Scopus subject areas

  • Otorhinolaryngology
  • Dentistry(all)
  • Cell Biology

Cite this