Hans-Peter Klöcking and Renate Klöcking
Proceedings of the 14th International Peat Congress
bimodal-effect, blood-coagulation, humic-substances, thrombelastography
Theme IV. Chemical, physical and biological characteristics of peat
This study was performed in order to evaluate the dose-dependent effect of different humic acid (HA) preparations on blood coagulation. Using the thrombelastographic method we examined HA from Altteich Peat (Eastern Saxony, Germany), sodium humate from an ombrotrophic mire in Mecklenburg-Western Pomerania, Germany, and the IHSS Reference HA from Waskish Peat (Minnesota, USA). The results revealed a strikingly bimodal behaviour of the tested HA: at high concentrations (250-1000 μg/ml) they prolong the reaction time, i.e. the period of time necessary until the beginning of clot formation, by two- to twelvefold (anticoagulant effect) whereas they at low concentrations (0.9-31.3 μg/ml) tend to reduce the reaction time by an average of 25 % (procoagulant effect).