Sea cucumbers are marine invertebrates with important ecological roles and a food delicacy with high market value. This study investigated the compositional profile and nutritional features of two Mediterranean sea cucumbers, Holothuria polii and Holothuria tubulosa, harvested in Adriatic Sea and Ionian Sea, Southern Italy. The macronutrients were determined by AOAC methods. The minerals were determined by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and fatty acids by Gas Chromatography-Mass Spectrometry/ Flame Ionization Detector (GC-MS/FID). Total mercury content was analyzed by Thermal Decomposition-Amalgamation-Atomic Absorption Spectrophotometry. Results showed that holothurians from the two basins are good protein (average 38-60 % dry mass) and mineral (32-37 % dry mass) sources, have a very low lipid content (1-3.7 % dry mass) and negligible mercury levels (0.016-0.038 mg kg-1 dry mass). H. polii showed a higher nutrient density, especially regarding minerals, with calcium, sodium and magnesium as the major ones. The analysis of fatty acid profiles enabled the identification of specific markers, reflecting habitat characteristics, seasonality, and dietary attitudes of holothurians. High percentages of arachidonic acid (47-65 % of total polyunsaturated fatty acids) and remarkable levels of branched-chain (6-9 % of total fatty acids) and odd-chain saturated fatty acids (1.7-3.8 % of total fatty acids), trophic markers of benthic food webs and sediment microbiota, were characterizing traits. Principal Component Analysis showed a neat discrimination of holothurians based on the species and harvesting site. Results underscore the nutritional properties of Mediterranean holothurian as part of a balanced diet, highlighting their potentialities as sources of molecules of nutritional and nutraceutical interest.

Proximate composition, unsaponifiable lipid components (cholesterol, squalene, tocopherols, all-trans retinol, total carotenoids) and fatty acid profile were evaluated on red mullet (Mullus barbatus) caught in the Central Tyrrhenian and Central Adriatic seas (Italy). The study was conducted in spring, the reproduction period, and in autumn, the period of maximum recruitment and market demand for this species. Results showed that, in fish from both sites, protein (18.1-18.8 g 100 g(-1)), nonprotein nitrogen (0.32-0.35 g 100 g(-1)), ash (1.27-1.42 g 100 g(-1)) and cholesterol (56.8-73.7 mg 100 g(-1)) contents were almost stable. Total lipid levels were highly variable, with very low levels in spring (0.96-1.48 g 100 g(-1)) and high levels in autumn (7.28-8.72 g 100 g(-1)). On a total fatty acids basis, polyunsaturated fatty acids (PUFA) were significantly higher in spring (30-40% of total fatty acids), when fish was lean, than in autumn (20%), while monounsaturated fatty acids were significantly higher in autumn (35-38%) than in spring (18-29%). Saturated fatty acids were almost stable throughout the year (34-39% of total fatty acids). Red mullet from the two sites showed a good nutritional value; in particular they proved to be a good source of n-3 PUFA, which accounted for 75-80% of total PUFA, regardless of the fishing season. However, it was in autumn that red mullet exhibited the highest content of n-3 PUFA (>1000 mg 100 g(-1) wet fillet). The comparison of samples by geographical origin showed no difference in autumn, while slight differences were observed in spring. (C) 2015 Elsevier Inc. All rights reserved.

European perch (Perca fluviatilis) harvested from three lakes of Central Italy were studied in different seasonal periods of a year to evaluate their nutritional quality and some safety aspects related to the pollution of the aquatic environment. The lakes considered, located in the Latium region, differed with respect to their volcanic (Bolsena and Bracciano Lakes) or artificial (Salto Lake) origin. Fillets of fish caught in the three lakes were characterised by good protein (17–19%) and mineral contents and low lipid levels (0.6–1.2%) throughout the year. Total lipids were characterised by low cholesterol levels (41.9–74.7 mg/100 g) and high percentages of total n − 3 polyunsaturated fatty acids (27.7–33.8% of total fatty acids), in particular docosahexaenoic acid (14.2–25.3% of total fatty acids). The qualitative analysis of the stomach content of perch confirmed their predatory feeding behaviour. The chemical and nutritional profiles of perch from the three lakes were comparable except for rubidium and cesium levels, which were higher in the muscle tissues of perch from the volcanic lakes. These minerals may represent elements of traceability of the origin of fish. Low levels of organochlorine pesticides and polychlorinated biphenyls, well below the Italian and European action limits, were detected in the muscle tissue of perch from all three lakes.

Whitefish (Coregonus lavaretus) from Italian lakes of volcanic or artificial origin were studied in different seasonal periods for their nutritional properties and for some safety aspects. Fish fillets were characterized by good protein levels (17.6–20.4g/100g wet fillet) and low total lipid contents (1.1–4.2g/100g), variable during the year, the highest levels being attained in the summer season. Whitefish were also a good source of essential minerals like selenium, zinc and iron, while very low mercury levels were detected in all samples. Rubidium and caesium were found at significantly higher levels in muscle of fish from the lakes of volcanic origin. These minerals may represent elements of traceability of the origin of fish. Total lipids were mainly characterized by low cholesterol levels (43.0–60.4mg/100g wet fillet) and by high proportions of total n-3 polyunsaturated fatty acids (21.5–32.1% of total fatty acids). The qualitative analysis of the stomach content of whitefish evidenced a prevalence of zooplanktonic species, mainly Daphnia spp., in their diet. The levels of organochlorine pesticides and polychlorinated biphenyls detected in whitefish from the lakes under study were always well below the Italian and European action limits.