Oxidative stress, metabolic activity and mercury concentrations in Antarctic krill Euphausia superba and myctophid fish of the Southern Ocean

• Published in: Marine Pollution Bulletin
• Main Authors: Seco, José, Freitas, Rosa, Xavier, José, Bustamante, Paco, Coelho, João, Coppola, Francesca, Saunders, Ryan, Almeida, Ângela, Fielding, Sophie, Pardal, Miguel, Stowasser, Gabriele, Pompeo, Giulia, Tarling, Geraint, Brierley, Andrew, Pereira, Eduarda
• Other Authors: Universidade de Aveiro, Scottish Oceans Institute University of St Andrews (SOI), School of Biology University of St Andrews, University of St Andrews Scotland -University of St Andrews Scotland, British Antarctic Survey (BAS), Natural Environment Research Council (NERC), Marine and Environmental Sciences Centre (MARE UC), Universidade de Coimbra Coimbra, LIttoral ENvironnement et Sociétés - UMR 7266 (LIENSs), Institut national des sciences de l'Univers (INSU - CNRS)-La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2021
• Subjects: Toxicity; Biochemical performance; Antioxidant capacity; Baseline; [SDV.TOX.ECO]Life Sciences [q-bio]/Toxicology/Ecotoxicology; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Antarctic; Southern Ocean; Antarc*; Antarctic Krill; Antarctica; Euphausia superba
• Online Access: https://hal.science/hal-03489978; https://hal.science/hal-03489978/document; https://hal.science/hal-03489978/file/Seco%20et%20al%202021%20MPB.pdf; https://doi.org/10.1016/j.marpolbul.2021.112178

International audience Indicators of oxidative stress and metabolic capacity are key factors in understanding the fitness of wild populations. In the present study, these factors were evaluated in the pelagic Southern Ocean taxa Antarctic krill (Euphausia superba) and myctophid fish (Electrona antarctica, Gymnoscopelus braueri and G. nicholsi) to establish a baseline record for future studies. Mercury (Hg) concentrations were also analysed to evaluate its potential impacts on species biochemical performance. E. superba had higher metabolic activity than most of the myctophid species, which may explain the comparatively lower energy reserves found in the former. The activity of antioxidant enzymes showed, generally, a lower level in E. superba than in the myctophid species. The lack of any relationship between Hg concentrations and organisms’ antioxidant and biotransformation defence mechanisms indicate that levels of Hg accumulated in the studied species were not high enough to affect their biochemical processes adversely.