Cnidarian antioxidant potential and protein content of two anemones sea collected in South West Mediterranean

Protein content and antioxidant enzyme activities were investigated in Anemonia viridis and Anemonia rustica, two symbiotic cnidarians collected from the western Algerian Mediterranean coast. This study aimed to assess the antioxidant defense mechanisms in these organisms. Mediterranean symbiotic cnidarians serve as excellent models for investigating oxidative stress mechanisms and their remarkable resilience to atypical oxidative conditions. Their survival hinges on maintaining a delicate balance of antioxidants. This study evaluated the protein content and the activities of the key antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and reduced glutathione (GSH) of Anemonia viridis (Forskal, 1775) and Anemonia rustica (Risso, 1827) collected from Kristel Bay on the western Algerian Mediterranean coast. The results revealed significant (p<0.05) variability in total tissue proteins, with A. rustica exhibiting higher levels in its body (2.30 ± 0.15 mg/g) compared to its tentacles (1.76 ± 0.39 mg/g) and the body of A. viridis (1.79 ± 0.20 mg/g). CAT and reduced GSH activity did not show significant variation across different body parts or species. In contrast, A. rustica displayed significantly higher SOD levels in its body (67.22 ± 4.92 U/mg protein) compared to A. viridis (24.26 ± 2.79 U/mg protein) and its own tentacles (22.96 ± 2.4 U/mg protein). Correlation analysis demonstrated a moderate negative correlation between protein content and CAT, a moderate positive correlation between protein content and SOD, and a strong negative correlation between protein content and GSH. These findings provide insight into the physiological adaptations of symbiotic cnidarians and highlight their potential as sources of valuable marine bioactive compounds.