Possible Interaction: Carotenoids and Hydrogen Peroxide

“Several mechanisms have been suggested for carotenoid protection in biological systems, which include the deactivation of electronically activated species, such as singlet oxygen and the deactivation of reactive chemical species, such as peroxyl or alkoxyl radicals that can be generated within cells and might otherwise initiate harmful oxidative reactions.”

“The protocol describes a representative feeding experiment by adding carotenoids to the nematode growth medium and after an incubation period, the C. elegans populations fed with carotenoids are exposed to an acute oxidative stress by using H2O2 as oxidative agent.”

“Oxygen vector and oxidative stress induced by hydrogen peroxide can promote carotenoid production significantly under the two-stage culture.”

“When peroxidation was induced by singlet oxygen both carotenoids effectively inhibited the formation of hydroperoxides with quenching activity only observed at low singlet oxygen concentrations, while scavenging still dominated.”

“The presence of carotenoids resulted in tolerance to hydrogen peroxide.”

“It exhibited the highest survival rate under oxidative stress and the carotenoid production thereof was enhanced after exposure to 7 mM H2O2.”

“It is demonstrated that carotenoids react with peroxyl radicals only slightly more reactive than lipidperoxyl radicals neither by electron transfer nor by hydrogen atom donation, but by adduct formation.”

“An increase in hydroperoxidation with dose was coupled with a decrease in carotenoids and vitamin A. Radiolytic decomposition of various amino acids was not random, indicating that the secondary reactions of free radicals from the oxidized lipids were also significant in the selective damage to amino acids.”

“In the red pigmented strains, H2O2 induced a significant decrease in one carotenoid (X5), which could be responsible for the antioxidant activity.”