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178 A. Reale et al.

Among the polyunsaturated fatty acids, EPA showed the highest levels (P< 0.05) in
Palinurus elephas followed by Sepia officinalis and the Scorpaenidae.Also, the C20:4 n6 acid
showed the highest levels (P< 0.05) in P. elephas, but no statistical significant differences
were found among the other species.
Statistically significant differences (P< 0.05) were observed among the species for the
sum of saturated, monounsaturated, and polyunsaturated fatty acids and for the sum of n-6
polyunsaturated fatty acids. Data reported in table 3 emphasize that, compared with the other
species, S. officinalis had the highest values of saturated fatty acids and the lowest values
of monounsaturated fatty acids, whereas P. elephas showed the lowest levels of saturated
fatty acids and the highest levels of polyunsaturated fatty acids. No statistically significant
differences were observed between the two Scorpaenidae for saturated and monounsaturated
fatty acids, whereas Scorpaena porcus was found to be the species with the lowest amount of
polyunsaturated fatty acids.
All the species showed a high content of polyunsaturated fatty acids due to high percentages
of n-3 series, especially EPA and DHA, with an n-3/n-6 ratio always >1. The values of n-3
polyunsaturated fatty acids are also higher than those of the same or similar species caught in
different areas [17].
The fatty acids of the n-6 series characterize the lipid composition of terrestrial animals and
Downloaded At: 20:22 7 January 2011 the fatty acid series for the enzymes involved in metabolism, leading to various pathologies
are precursory substances with a strong thrombotic and inflammatory effect.
The ratio n-3/n-6 is of great importance for human health due to the competition of both

[20]. Furthermore, for the phospholipids of the membrane and the plasma, this ratio n-3/n-6
plays a determined role in the fluidity of the membrane, in genetic expression, in the regulation
of lipid levels, and in the immune response. All these factors can prevent or favour the onset
not only of cardiac illnesses, but also of hypertension, diabetes, arthritis, multiple sclerosis,
cancer, and other auto-immune pathologies [21]. The values of indexes relating to dietetic
factors linked with coronary diseases are reported in table 4.
Statisticallysignificantdifferences(P< 0.05)wereobservedamongthedifferentspecies;in
particular, for Palinurus elephas the saturated/polyunsaturated ratio (S/P) and the atherogenic
index (AI) were lower than those calculated for the other three species, on the contrary Sepia
officinalis showed the highest values both for the saturated/polyunsaturated ratio and for
the atherogenic index, whereas no significant differences were observed between the two
Scorpaenidae. Thrombogenic indexes (TI) did not show any significant differences among the
species.
The AI of Sepia was very high, even higher than that reported by Ulbricht and Southgate
[15] for lamb (1.00); the values of AI for Scorpaenidae were very similar to the AI values
reported for bovine meat (0.72), whereas P. elephas showed a good AI value very similar to
that of mackerel (0.28).
Instead, TI were often lower than those of the aforementioned products: lamb (1.58), bovine
meat (1.08), and lean pork (1.37), with the exception of mackerel (0.16), a marine fish with
the highest content of n-3 polyunsaturated fatty acids.

Table 4. Ulbricht and Southgate indexes correlated with cardiovascular disease.
Palinurus elephas Sepia officinalis Scorpaena scrofa Scorpaena porcus
S/P 0.36a 1.22c 0.78b 0.70b
AI 0.25a 1.12c 0.74b 0.71b
TI 0.24 0.48 0.51 0.43

Note: Values in the same row with different letters are significantly different (P< 0.05).
S/P: saturated/polyunsaturated fatty-acid ratio; AI: atherogenicity index; TI: thrombogenicity index.