Accumulation of Protoporphyrin IX in the Presence of Peroxidizing Herbicides

Peroxidizing herbicides were assayed for their capacity to accumulate tetrapyrrole-like compounds in the liquid culture medium when growing the xanthophycean alga Bumilleriopsis filiformis. W e have isolated and purified this compound by H P L C . For identification optical, fluorescence, N M R and mass spectroscopy were employed. All these techniques showed that the accumulation product is protoporphyrin IX. This tetrapyrrole was found, although to a different extent, using either chlorophthalim, oxadiazon, oxyfluorfen or LS 82-556. Accumulation of protoporphyrin IX caused by peroxidizing compounds was also found in light-grown Bumilleriopsis cells and heterotrophically (dark-)grown Scenedesmus cells, but neither in light-grown Scenedesmus cells nor in dark-grown Neurospora.