[Quenching of singlet molecular oxygen by screening pigments-- melanins and ommochromes].
Synthetic DOPA-melanin and natural screening pigments--sepiomelanin and ommochromes are shown to quench the luminescence of singlet molecular oxygen (1O2) in aqueous (D2O, pD = 7.5-8.1) solutions. The rate constants of 1O2 quenching are found to be equal to (1.2 +/- 0.6) 10(8) M-1 s-1 for monomeric units in DOPA-melanin and to (3 +/- 1) 10(6) M-1 s-1 for ommochromes. The data suggest that screening is not the only function of melanins, which may play a role of inhibitors of photodynamic damage in living tissues.
Egorov
S Iu
SIu
Dontsov
A E
AE
Krasnovskiĭ
A A
AA
Ostrovskiĭ
M A
MA
D000818:Animals; D008543:Melanins / Q000494:pharmacology*; D010100:Oxygen; D010640:Phenothiazines / Q000494:pharmacology*; D010777:Photochemistry; D010860:Pigments, Biological / Q000494:pharmacology*; D026082:Singlet Oxygen
D008543:Melanins; D010640:Phenothiazines; D010860:Pigments, Biological; C002772:ommochrome; D026082:Singlet Oxygen; D010100:Oxygen
Tushenie singletnogo molekuliarnogo kisloroda ékraniruiushchimi pigmentami--melaninami i ommokhromami.