Poster Presentation Australian Society for Microbiology Annual Scientific Meeting 2018

Searching for the remarkable among the unremarkable: Neglected plants from the New England region (NSW) and their antibacterial compounds (#322)

Dane Lyddiard 1 , Ben W Greatrex 1
  1. School of Science & Technology, University of New England, Armidale, NSW, Australia

A variety of antibacterial drug discovery approaches are being undertaken by researchers to fill the treatment gaps left by growing antibiotic resistance. As plants rely heavily on small molecules to protect them from microbial invasion, one approach is to screen the botanical world for antibacterial compounds. While some plant species, such as Melaleuca alternifolia (the source of tea tree oil), have garnered significant interest for potential antibacterial uses in the past, many species remain neglected.  A selection of plants growing in the New England region of NSW, which had been poorly studied for antibacterial phytochemistry, were screened leading to the discovery of an active methanol extract from an endemic species, Olearia aff. elliptica.  Thin layer chromatography bioautography and activity-guided partitioning and fractionation led to the isolation of known and new compounds (such as ent-labdane glycosides and an ent-labdane diacid), including those with antibacterial properties.  Further work is being undertaken to assess the extent of antibacterial activity and the toxicity of isolated compounds.  The limitations of phytochemical screenings are reaffirmed: the problem of ‘rediscovering’ known compounds, toxicity concerns and the prevalence of phytochemicals with low to moderate antibacterial activity.