Bioluminescence as the Basis for the Detection of Trichothecenes

摘要

The marine dinoflagellate, Pyrocystis lunula, luminesces strongly when subjected to a shear stress such as in stirring. The intensity of the luminescence reaches a maximum after approximately 2 hours of darkness. It was found that certain trichothecenes (popularly known as Yellow Rain compounds) inhibit the luminescence of Pyrocystis lunula; e.g. in the assay developed during this study, 2 micrograms of T-2 quench the luminescence of a test culture by 40%. The assay consists in preparing a suspension containing 100 cells/ml, storing it in the dark for 2 hours, then stirring mechanically for 1-1/2 minutes during which the output of a photometer absorbing the light produced is plotted on a strip chart recorder. Comparisons are then made of the displacement of the recorder pen with control cultures vs those containing a toxin. Because an epoxide group is a necessary component of the trichothecences, there was a possibility that the assay method was simply responding to the epoxide moiety. This is not the case, however, since a series of epoxide-containing compounds failed to inhibit the luminescence of the organism. It is recommended that further studies be conducted to determine the feasibility of adapting this assay to field use. Each assay requires less than two minutes, and no special workup of field samples is required. Keywords: Roridin; Verrucarin; and Weathering.