Oxidative metabolism related to Fe content in aquatic photosyntetic and non-photosyntetic organisms

GONZÁLEZ PM; MALANGA G; PUNTARULO S

Buenos Aires

Congreso; VIII Meeting of the Society for Free Radical Biology and Medicine-South American Group; 2013

Since natural Fe concentrations may affect oxidative metabolism, digestive gland from bivalves (Mya arenaria, Mytilus edulis platensis, Mytilus edulis chilensis) and algae (Navicula sp.), were analyzed. Fe content in sediments of the respective analyzed species was 7.5 ± 0.6, 1.4 ± 0.4, 15 ± 1 and 33.5 ± 0.7 mg/g DW in Wadden Sea, San Antonio Oeste, Beagle Channel and Carlini Base, respectively. Total Fe content was 0.9 ± 0.2, 0.6 ± 0.05 and 7.8 ± 0.2 nmol/mg FW in M. arenaria, M. edulis plantensis and M. edulis chilensis, respectively and 18 ± 2 nmol/104 cell in Navicula sp. Labile iron pool (LIP) content showed higher values in animals with higher total Fe content. The oxidation rate of dichlorofluorescein diacetate was 264 ± 2, 29 ± 4 and 18 ± 2 a.u./min mg prot FW in M. arenaria, M. edulis plantensis and M. edulis chilensis, respectively. Reactive oxygen species generation seemed controlled by ascorbate content and catalase activity limiting lipid and ascorbyl radical content. These results showed the influence of Fe content in the environment on the oxidative metabolism, and the presence of the LIP could be involved in the basal stress detected.