2.8. Lipid peroxidation
The amount of lipid peroxidation products in leaves
was estimated by determining the malonyldialdehyde
(MDA) content in the leaves according to Hartley-
Whitaker et al. [31] with minor modifications as in
Spano` et al. [32]. Powder from freeze-dried leaves
material (10 mg) was mixed with TBA reagent (4 mL of
10% w/v trichloroacetic acid + 0.25% w/v thiobarbituric
acid), heated (95 8C for 30 min), cooled for 15 min and
centrifuged at 2000 g for 15 min. The level of MDA
(155 mM/cm extinction coefficient) was measured as
specific absorbance at 532 nm, by subtracting the non-
specific absorbance at 600 nm [33] and expressed as
nmol/g DW