What Is A Free Radical - Ústav lékařské chemie a biochemie

Further fate of lipid peroxides
Ionising radiation:
Hydroxyl radical originates from ionisation of water:
H 2 O + hν → H· + OH·
Reactive oxygen species in the body:
One-electron reduction of oxygen (mitochondria,
NADPH oxidase) forms superoxide O 2·–
Dismutation of superoxide produces hydrogen peroxide:
O 2·–
+ O 2·–
+ 2 H + → O 2 + H 2 O 2
Fenton reaction with Fe or Cu converts peroxide to
hydroxyl radical:
H 2 O 2 + Fe 2+ → OH – + OH· + Fe 3+
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