Identification of molecular biomarkers for food quality assessment of oysters exposed to hypoxia

Abstract

Hypoxia, corresponding to a low oxygen concentration of less than 2.8 mg O2/L (91.4 mM), may cause serious problems in marine environments. In this study, we applied differential display PCR and fatty acid analysis to investigate molecular biomarkers for assessing hypoxic effects using the oyster, Crassostrea gigas, as a model organism. Oysters were exposed to normoxic (7.6 mg O2/L) or hypoxic (1.8 mg O2/L) concentrations of dissolved oxygen for 2 days. We found that glutamine synthetase (GS) gene expression decreased and glutathione S-transferase (GST) gene expression increased in oysters exposed to hypoxia. In addition, linoleic acid content significantly decreased following hypoxic exposure compared with controls. Collectively, our findings indicate that GS and GST expression levels and linoleic acid content are potentially good biomarkers for analyzing the effects of hypoxia.biomarkers for assessing hypoxic effects using the oyster, Crassostrea gigas, as a model organism. Oysters were exposed to normoxic (7.6 mg O2/L) or hypoxic (1.8 mg O2/L) concentrations of dissolved oxygen for 2 days. We found that glutamine synthetase (GS) gene expression decreased and glutathione S-transferase (GST) gene expression increased in oysters exposed to hypoxia. In addition, linoleic acid content significantly decreased following hypoxic exposure compared with controls. Collectively, our findings indicate that GS and GST expression levels and linoleic acid content are potentially good biomarkers for analyzing the effects of hypoxia.