Fig. 3.

Superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) activities and hydroxyl free radical scavenging capacity (HFRSC) and concentrations of malonaldehyde (MDA) in Kappaphycus alvarezii (a) and Kappaphycus striatum (b) thalli exposed to 26 °C (the control) and low temperatures (23, 20 and 17 °C) for 2 h, respectively. All values of the above parameters are expressed relative to those of their controls (the controls are taken as 1) and are presented in relative units. (Data are means ± SD of three replicates (n = 3). For each parameter, for each species, the treatments with a star (*) are significantly different from the respective control, p < 0.05)