In the present study, our objective was to reexamine
cogongrass for potential allelochemicals, using a systematic
bioassay-guided isolation approach that we have successfully
used in the past for discovery of phytotoxic phytochemicals
(e.g., Castro et al. 2010, Morimoto et al. 2009). We identified
a new phytotoxic constituent of the essential oil of the aerial parts of cogongrass, megastigmatrienone, also known as
tabanone. Tabanone caused injury via an unknown mechanism
of action resulting in loss of plasma membrane integrity