Generation of ¹O₂ (¹Δ_g) by DHN-melanin, polyketides intermediaries and living whole mycelium of <i>M. fijiensis</i>.

<p>A representative monomol light emission spectra of ¹O₂ at 1270 nm obtained after pulsed laser excitation at 532 nm. (<b>A</b>) Melanin pigments adjusted to 0.6 Abs in 0.1 M NaOD. Red line corresponds to secreted melanin and black line is from mycelium melanin. The phosphorescence intensity of secreted melanin was higher than mycelium melanin. (<b>B</b>) phosphorescence emission of synthetic melanin (M8136), (<b>C</b>) Reddish-brown pigment composed by polyketides and naphtoquinones mixture, was dissolved in D₂O at Abs 0.6. Black line shows the phosphorescence of culture amended with tricyclazole and red line shows the phosphorescence of pyroquilon inhibitor. (<b>D</b>) Active whole mycelium grown in potato-dextrose culture medium. 250 mg of mycelium was used for each experiments. A black and red line corresponds to mycelium from green-black <i>Mf-1</i> strain cultured in liquid and agar media respectively. Blue and Green lines are emission spectra of albino<i>102</i> strain cultured in liquid and agar media. (<b>E</b>) Singlet oxygen production of 1,2 DHN used as standard dissolved in acetonitrile; (<b>F</b>) Emission spectra of dimethylnaphthalene endoperoxide.