Antibacterial and anti quorum sensing activity of Justicia adhatoda leaf extract against Salmonella SPP.

Salmonella spp. produce an auto-inducer I (AI-I) molecules for cell to cell communication, which also known as quorum sensing. Justicia adhatoda, commonly known as adulsa is popularly used against cough and related ailments because of its antibacterial activity. During present study antibacterial potential of methanolic, ethyl acetate and n-hexane extracts of Justicia adhatoda leaves has been investigated against pathogenic bacteria belonging to Salmonella spp. The results indicated that methanolic extracts of adulsa have antibacterial activity against Salmonella typhimurium and Salmonella paratyphi A. These extracts were also found to be significantly reducing the levels of AHL(n-acyl homoserine lactone- AI-I) and thereby could interfere with the cell to cell communication and pathogenicity in salmonella spp. The results indicated that methanolic leaf extracts of Justicia adhatoda could act as potential anti- quorum sensor.