Identification of volatile organic compounds (VOCs) from bacteria and yeast causing growth inhibition of sapstain fungi

This paper describes an experiment to identify volatile organic compounds (VOCs) from a range of three bacteria and one yeast strain that had previously been shown to be inhibitory to selected sapstain fungi. The bacteria and yeast were cultured on two media, malt extract (ME) and tryptone soya (TS) and the VOCs trapped on chromatographic adsorbant before being analysed by Integrated Thermal Desorption -GC-MS. Since sapstain fungi were only inhibited by VOCs produced on the TS media, it was possible to use Principle Component Analysis to highlight the individual VOCs that are most likely to be responsible for the inhibition. A number of ketones together with dimethyl disulphide and dimethyl trisulphide were highlighted. The importance of VOC production by organisms during the biological control of sapstain is discussed.