Oxidative balance in macroalgae from Antarctic waters. Role of Fe

GONZÁLEZ PAULA M.; DEREGIBUS, D.; MALANGA, G.; CAMPANA G.; QUARTINO M.L.; PUNTARULO S.

La Paz

Conferencia; Second International Conference on Oxidative Stress in Aquatic Ecosystems; 2015

Centro de Investigaciones Biológicas del Noroeste

Excessin Fe content was identified as responsible for seaweed stress. In Potter Cove,Antarctic, the particulate Fe content at 0 m near the glacier in D Island (ID)is significantly higher than in Peñón Pesca (PP). The hypothesis of this workwas that the basal oxidative profile of Gigartinaskottsbergii and Himantothallusgrandifolius follows a differential pattern due to adaptive factors. Dailymetabolic carbon balance was significantly lower in both macroalgae taken fromID as compared to those from PP. Lipid radical (LR●) content, measuredby EPR, was significantly higher in G.skottsbergii from ID as compared to PP samples. However, H. grandifolius showed significantlylower values in ID in comparison to those from PP. b-Carotene (b-C) content (measured by HPLC) was significantlylower in G. skottsbergii from ID as comparedto PP, and the ratio LR● content/b-C content was increased by 6-fold in samplesfrom ID as compared to samples obtained from PP. However, the b-C content showed no significantly differences inH. grandifolius from both areas. TheLR● content/b-Ccontent index in this alga was significantly lower (26%) in samples obtained fromID as compared to PP. Total Fe content (measured spectrophotometrically) in G. skotsbergii was significantlydifferent, 1.0±0.5 and 2.9±0.7 nmol/mg FW, in samples from PP and ID,respectively. However, in H. grandifoliusthis parameter showed no significantly differences between both areas. Thepresented results in G. skottsbergiisuggested changes in the oxidative cellular balance at the lipophilic level probablyrelated to the higher environmental Fe in the ID, as compared to the PP region.Contrary to the subtidal red alga G.skottsbergii, the brown macroalga H.grandifolius, that is an endemic species from Antarctic waters predominatingon vertical rocks, could be better adapted to the environmental changes of theregion.