Light-induced absorbance changes in the fungus Verticillium agaricinum [action spectrum, carotenogenesis, photo-bleaching]

Light‐induced absorbance changes were investigated in vivo in the fungus Verticillium agaricinum (Link) Corda. There was a broad light‐induced absorbance decrease in the blue and near UV with a maximum at 384 nm. An action spectrum indicated that the absorbance changes were due to photo‐bleaching of a pigment with an absorption spectrum that was similar to the action spectrum. Neither redox reactions nor energy metabolism were involved in the photo‐bleaching process. A direct comparison of action spectra for light‐induced absorbance changes and photo‐induction of carotenogenesis suggests that the photo‐bleaching may not be related to photo‐induction of carotenogenesis.