Evaluation de la qualite nutritionnelle de la sardinelle ronde Sardinella aurita (Valenciennes, 1847) du golfe de Tunis

Abstract

The aim of this study is to evaluate the levels of oligo-elements (Mg, Ca, Na, K, Fe and Mn) and fatty acids in four tissues (muscle, liver, brain and gonads) of a pelagic teleost species, the Round Sardinella (Sardinella aurita). This pelagic fish is one of the most important landed species in gulf of Tunis. The specie is considered as a common species in this area throughout the all seasons. In this study, organotropism, and seasonal effect of oligo-elements and fatty acids accumulation was determined. The concentrations of Mg, Ca, Na, K, Fe and Mn were performed using Flame Atomic Absorption Spectrophotometry. Fatty acids were analysed by Gas Chromatography. The results showed a seasonal variation in all elements in gonad with a peak in summer. Additionally, the brain is the preferential site for accumulation of Ca and Na and liver for Fe, Mg and Mn. The results concerning fatty acids demonstrate that the levels of monounsaturated and saturated acids increase when the levels of polyunsaturated fatty acids decrease in all tissues of Round Sardinella. Lipid levels of displayed pronounced seasonal fluctuations, with the highest value in summer. In addition, the highest level of index n-3/n-6 was observed in flesh during spring season. It is concluded that the Round Sardinella is a particularly healthy item in the human diet during spring period, when balanced n-3/n-6 ratios and EPA and DHA levels are considered.