n vitro anti leptospiral activity of ethanolic extract of the leaf of Andrographis paniculata Nees (Acanthaceae)

Leptopsirosis is a zoonotic infection with a worldwide distribution that is associated with both endemic and epidemic diseases with the incidence of disease being highest in tropical climates.The MIC of ethanolic extract of the leaf of Andrographis paniculata Nees (Acanthaceae) for a total of 5 leptospiral serovars were tested for their susceptibility to its antileptospiral activity.Among the tested serovars L. australis, L. icterohaemorrhagiae, was found to be most susceptible to ethanolic extract and least in L. javanica were as moderate in L. autumnalis, L. pomona, Minimum MIC was found in L.australis, L.icterohaemorrhagiae, it was about 200µg/ml concentration.MIC was determined based on movement of leptospira.Better results were obtained only after 12hrs at lower concentration where as at 5 fold and 10 fold concentrations effect was noticed after 3 and 5 hrs respectively.Doxycycline used as standard.It was most effective and less toxic particularly for liver and kidney damaged patients.