*4.8. Glutathione Levels*

GSH content was determined following the Hissin and Hilf (1976) method with some modifications [46]. In 96-well plates, phosphate-EDTA buffer (pH 8.0, 150 μL) was mixed with total extract samples (50 μL). Then, O-phthalaldehyde (OPT) was added (20 μL) and samples were incubated for 15 min in the dark. Fluorescence was measured at an excitation/emission wavelength 360/460 nm. A standard curve of reduced GSH was used.
