Table 1. Main reactive oxygen species.

Name	Formula	Formation
Superoxide	02−	Intermediate in 02 reduction to H2O
Hydroxyl	HO	Powerful oxidant in biological systems
Peroxyl	ROO	Low oxidant ability, but high diffusibility
Alkoxyl	RO	Medium oxidant ability with lipids
Hydrogen peroxide	H202	Originated from 02
Hypochlorous acid	HClO	Formed through mieloperoxidase action
Single oxygen	lO2	Molecularly excited oxygen through sunlight and radiation

On the basis of the report by Olguín and Guzman.²⁹