Antibacterial property of Aconitum heterophyllum root alkaloid

In our earlier study, alkaloid extract from Aconitum nagarum root was reported for antibacterial activity, where aconitine was identified as bioactive compound. The aim of the current study was to analyze the antibacterial activity of the root alkaloid extract of another important Aconitum species, namely Aconitum heterophyllum. This alkaloid extract showed antibacterial activity against S. aureus, B. bronchiseptica, B. subtilis, P. putida and X. campestris, while this activity was negligible against S. typhimurium, E. coli and P. fluorescence. The extract resolved to 9 bands and none of the band corresponded to aconitine in thin layer chromatography (TLC). These bands were eluted and analyzed for antibacterial activity. Most of the eluted bands displayed antibacterial activity, which was comparatively high with the fifth (Rf: 0.47) and ninth (Rf: 0.91) band. Mode of action of these eluted bands was cidal for S. aureus, B. bronchiseptica and B. subtilis, while the effect was static for other bacterial species. Thus, the present study revealed the antibacterial activity of A. heterophyllum alkaloids from root was due to synergistic effect of different alkaloids.