Solid phase extraction and subsequent identification by gas-chromatography-mass spectrometry of a germination cue present in smoky water

Aqueous extracts of plant-derived smoke (smoky water) are a complex mixture of thousands of components. Solid phase extraction (SPE) cartridges of varying polarity were trialed for their effectiveness in cleaning up smoky water, prior to subsequent analysis. The most effective SPE cartridge used was normal phase silica bonded with aminopropyl (NH2) with hexane/dichloromethane/methanol mixtures as eluting solvents. This system retained all the active components and permitted elution of two active fractions, separated by an inactive fraction. Other cartridges tested either did not retain all active components or eluted active fractions successively, with more overlap between compositions. Active fractions, as identified by germination tests, were examined by GC-MS and were found to be sufficiently simplified to allow the identification of a new germination cue, 1, 8-cineole.