Singlet molecular oxygen quenching

The basic structure of carotenoids is a conjugated polyprenoid chain. Carotenoids exert a positive impact on human welfare. They show marked singlet molecular oxygen quenching capacity [11] and they protect against photosensitized peroxidation of lipids [12],... 

M. Montenegro, M. Nazareno, E. Durantini and C. Borsarelli, Singlet molecular oxygen quenching ability of carotenoids in a reverse-micelle membrane mimetic system. Photochem. Photobiol. 75 (2002) 353-361. 

S. Egorov et al.. Quenching of singlet molecular oxygen by carnosine and related antioxidants. Monitoring by 1270-NM phosphorescence in aqueous media. Biochem. Molec. Biol. Intern., 41 (1997) 687-694. 

N. Suzuki, I. Mizumoto, Y. Toy a, T. Nomoto, S. Mashiko, H. Inaba (1990). Steady-state near-infrared detection of singlet molecular oxygen A Stern-Volmer quenching experiment with luminol, superoxide dismutase, and Cypridina luciferin analogs. Agric. Biol. Chem., 54,2783-2787. 

The quenching of singlet molecular oxygen ( O ) by carotenoids and the mechanism by which this reaction protects against O mediated photo-oxidation reactions have been much discussed. 

Photo-oxidation.—Turro and co-workers report the rate constants for quenching of singlet molecular oxygen ( O2) by several strained molecules. The authors also discuss a non-photochemical method for determination of quenching constants of singlet oxygen involving thermolysis of l,4-dimethylnaphthalene-l,4-endoperoxide. 

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