Abstract
A classical ayurvedic polyherbal formulation namely Triphala was assessed for its anti-pathogenic potential against five different pathogenic bacteria. Virulence of four of them towards the model host Caenorhabditis elegans was attenuated (by 18-45%) owing to pre-treatment with Triphala Formulation (TF) (≤20 µg/ml). TF could also exert significant therapeutic effect on worms already infected with Chromobacterium violaceum (MTCC 2656), Serratia marcescens (MTCC 97) or Staphylococcus aureus (MTCC 737). Prophylactic use of TF allowed worms to score 14-41% better survival in face of subsequent pathogen challenge. Repeated exposure to this formulation induced resistance in S. marcescens, but not in P. aeruginosa. It also exerted a post-extract effect (PEE) on three of the test pathogens. TF was able to modulate production of quorum sensing (QS)-regulated pigments in three of the multidrug-resistant gram-negative test bacteria. Haemolytic activity of S. aureus was heavily inhibited under the influence of this formulation. P. aeruginosa's lysozyme-susceptibility was found to increase by ~25-43% upon TF-pretreatment. These results validate therapeutic potential of one of the most widely used polyherbal ayurvedic formulations called Triphala.