Seasonal and inter-annual lipid dynamics of spiny cheek grouper (Epinephelus diacanthus) in the southern coast of India

The muscle lipid, fatty acids and total cholesterol profiles of the spiny cheek grouper,Epinephelus diacanthus, collected from south-west (Arabian Sea) and south-east coasts (Bay of Bengal) of India were evaluated over four years (2008–2011) with regard to three seasons (pre-monsoon, monsoon and post-monsoon). Fatty acids were correlated with chlorophyll-aconcentration and sea surface temperature. Lipid content, total polyunsaturated, eicosapentaenoic and docosahexaenoic fatty acids of the samples from the south-west coast showed positive correlation with chlorophyll-aconcentration during the monsoon (r2 = 0.93, 0.97, 0.97 and 0.99, respectively). Higher hypocholesterolaemic/hypercholesterolaemic ratio (>1.0) and low atherogenic (<1.2), thrombogenicity (≤0.6) indices make the groupers collected from the coast of the Arabian Sea a valued candidate species for human nutrition. High levels ofn-3 fatty acids (>19% during post-monsoon), important in the human diet for their platelet anti-aggregating and blood pressure-reducing properties, for groupers collected from the south-west coast, with highern-3/n-6 fatty acid ratio (>5.1) proved this species from the coast of the Arabian Sea to be a desirable item in the human diet.