Oral Presentation Australian Society for Microbiology Annual Scientific Meeting 2018

Identifying changes in painted and polyester surfaces during the attachment and proliferation of three species of environmental fungi using Synchrotron-sourced macro ATR-FTIR microspectroscopy (#167)

Vi Khanh Truong 1 , Stephanie Owen 1 , Jitraporn Vongsvivut 2 , Mark J Tobin 2 , Shane MacLaughlin 3 , Russell Crawford 4 , Elena P Ivanova 4
  1. Swinburne University of Technology, Melbourne, VIC, Australia
  2. Infrared Microspectroscopy (IRM) Beamline, Australian Synchrotron, Clayton, VIC, Australia
  3. BlueScope Steel Research, Port Kembla, NSW, Australia
  4. School of Science, RMIT, Melbourne, VIC, Australia

Fungi are able to colonise and grow on many surfaces, including painted surfaces, under a variety of environmental conditions. This leads to surface deterioration and discolouration, eventually requiring costly repair or replacement. The development of surfaces that resist fungal colonisation is inhibited by a lack of research and understanding into the specifics of fungal attachment strategies. In this work, the attachment and proliferation of three characteristics fungal species found in indoor and outdoor environments are studied: Aspergillus niger ATCC 9642, which is particularly prevalent indoors; Aureobasidium pullulans ATCC 42773, the primary coloniser for paint in humid conditions and Epicoccum nigrum ATCC 9348, which has been identified as a coloniser of polymer-coated roof surfaces. Each species was incubated on either polymer-coated steel discs or the same steel discs covered with Interior Taubmans® Easycoat paint. Field-emission SEM was used to quantify cell attachment after 1, 3 and 7 days of incubation.  Synchrotron-sourced macro ATR-FTIR microspectroscopy was used to analyse chemical changes in the fungi and the surfaces as they attached and began to hyphenate. Microscale changes were identified related to fungal hypha, with the degree of change related to the species’ metabolic competency. Using macro ATR-FTIR microspectroscopy, it was found that the polysaccharides were detected at a maximum amount during early colonisation, suggesting that secreted polysaccharides may play an important role during initial fungal surface attachment. By identifying changes in fungal and surface chemistry during attachment and proliferation, we were able to identify potential attachment mechanisms of interest for future research. This will assist in developing surfaces that resist fungal colonisation and degradation.