PHYSIOLOGICAL AND BIOCHEMICAL RESPONSES OF PALYTHOA VARIABILIS (CNIDARIA, ANTHOZOA) FROM INTERTIDAL ZONE AFTER LOW TIDE EMERSION

Abstract

The objective was to investigate the biochemical responses in the intertidal zoanthid Palythoa variabilis following aerial exposure followed by immersion. The tidal regime was simulated in the laboratory to test whether emersion (3 hours) followed by immersion (1 and 3 hours) would elevate antioxidant defences, namely the activity of glutathione S-transferase (GST) and catalase (CAT). There was no effect of exposure on CAT; however, GST activity increased during emersion and after 1 hour of immersion, showing values nearly 3 times greater compared to the control. The results of this study provide evidence of the biochemical responses caused by aerial exposure in the coral Palythoa variabilis and its adaptive capabilities to cope with this stressor.

Key words: Intertidal; air exposure; Palythoa; DNA; Oxidative stress.