Antioxidants in the black mussel (Mytilus galloprovincialis) as an indicator of Black Sea coastal pollution

The biologically active compounds, antioxidant activities, and free radical scavenging effects of black mussel dry matter (Mytilus galloprovincialis)--(BMDM) were investigated. The extract from BMDM with absolute methanol (BMDMAMet) showed the strongest inhibition of lipid peroxidation as a function of its concentration, and was comparable to the antioxidant activity of butylated hydroxyanisole, at the same concentration of 0.2 mg/ml. The extract with 50%methanol/water (BMDM50%Met) had the weakest antioxidant activity, whereas other extracts such as 1.2 M HCl in 50%methanol/water (BMDM50%Met/HCl) exhibited an average inhibition of lipid peroxidation. BMDMAMet extract showed marked activities in free radical scavenging determined by beta-carotene bleaching (beta-carotene), nitric oxide (NO*) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) radical cation (ABTS*+ methods. The antioxidant activities of BMDMAMet extract determined beta-carotene, NO* and ABTS*+ methods showed the highest correlation coefficients (R2) such as 0.998, 0.9976 and 0.6103, respectively, with the presence of total polyphenols. BMDM50%Met had lower antioxidant ability than BMDM50%Met/HCl in different scavenging methods, indicating that the major antioxidant components in these extracts must be derived from the polyphenols. Correlation between proteins and antioxidants was very low (0.0318 and 0.0433). The mussel extracts from polluted areas have shown by all using methods higher antioxidant activity than from the clean ones. The results presented in this report indicate that the antioxidant activities of mussel extracts could possibly be an additional index of pollution characterization.