Comparative assessment of the antibacterial activity of three tephrosia species against helicobacter pylori

Abstract

The present study was carried out to provide evidence to the traditional use of three species Tephrosia calophylla, Tephrosia maxima and Tephrosia purpurea to treat ulcers in the regions of Andhra Pradesh. The plants were extracted with chloroform, methanol and then subjected to preliminary phytochemical screening. The antibacterial activity of the extracts against Helicobacter pylori was tested in vitro and in vivo. In vitro activity was screened using the disc diffusion method in Brucella agar supplemented with 7 % sheep blood. In vivo activity against Helicobacter pylori was screened in naproxen and Helicobacter pylori-induced ulcers in Swiss mice with triple regimen of clarithromycin, amoxicillin, omeprazole serving as the standard. The parameters evaluated were log CFU/g of stomach tissue, infection status by polymerase chain reaction, rapid test for urease and histopathological studies. Phytochemical screening indicated the presence of similar phytochemicals in all the three extracts. Methanol extracts of the plants exhibited high antibacterial activity in vitro. Tephrosia maxima showed potent activity against Helicobacter pylori-infected ulcer in rodents relative to Tephrosia calophylla and Tephrosia purpurea. Log CFU/g of stomach tissue was observed to be very low after treatment with Tephrosia maxima. Observations on infection status confirmed these findings. These results suggested that Tephrosia maxima to be an effective inhibitor of Helicobacter pylori-infected ulcer. Histopathological studies further supported these results. Mild inflammation and congestion were seen in the gastric mucosa of the mice treated with Tephrosia maxima methanol extract without any ulcer whereas with the other two plant extracts, slight increase in inflammation and congestion was observed.