Anti-bacterial Properties of the Annona montana

Bacterial pathogenesis and virulence is linked with cell to cell communication. Many plants have anti-quorum sensing (QS) compounds, which can inhibit the interaction within the bacterial community and weaken its pathogenicity. These compounds can be used to combat infections by interrupting the signaling pathways between bacteria. This approach of decreasing virulence through quorum sensing inhibition is different than killing or stopping the growth of bacteria because it will not lead to antibiotic resistance.  Annona montana has been known for producing acetogenin compounds, which have the potential to cure cancer. Some plants and certain parts of plants have more anti-QS compounds than others. Extracts of the leaves, fruit and bark of a mature A. montana tree were made using water, 80% methanol, 80% ethanol, absolute methanol and absolute ethanol. Biomonitor strains for the anti-QS activity Chromobacterium violaceum, Chromobacterium AHL mutant CV026, Agrobacterium tumefaciens and  Pseudomonas aeruginosa were grown in Lysogeny broth (LB) and LB-agar plates. The extracts were tested through disc diffusion assays on the bacteria to determine which part of the tree contained the most potent anti-QS compounds. The bacterial growth was recorded by counting the colony forming units (CFU) on agar plates and using a spectrometer to monitor the growth by recording the OD₆₀₀ . The objective of this study was to find a new source of anti-QS compounds that can be further developed  for medicinal purposes.