Quantification and localization of reactive oxygen species in marine macrophytes

Marine macrophytes, including seaweeds and seagrasses often experience risk from a wide range of anthropogenic stressors, climate variation, invasive species, and pathogens, and also from their exposure to low and high tidal cycle on daily bases. This stressful environment in their ecological niche triggers the generation of reactive oxygen species (ROS), including singlet oxygen (¹O₂), superoxide radicals (O₂ ⁻), hydrogen peroxide (H₂O₂), and hydroxyl radicals (OH ^· ). ROS being highly reactive molecules and unstable, their detection largely relies on measuring their reaction end products using diverse analytical approaches, including electron paramagnetic resonance, chemiluminescence, fluorescence, and spectrophotometry. In this chapter, methods for detection and localization of ROS using fluorescent probes such as dihydroethidium (DHE) and dichloro-dihydrofluorescein diacetate (DCFH-DA), and staining techniques using stains such as nitro blue tetrazolium (NBT) and diaminobenzidine tetrahydrochloride (DAB) are described.

Keywords: Seaweeds, seagrass, reactive oxygen species, oxidative stress, fluorescent probes