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Dal Zotto M.,University of Modena and Reggio Emilia | Santulli A.,Consorzio Universitario Della Provincia Of Trapani | Simonini R.,University of Modena and Reggio Emilia | Todaro M.A.,University of Modena and Reggio Emilia
Zoologischer Anzeiger | Year: 2016

Within the framework of a programme aimed at monitoring the impact of fish farming on the marine biota, we have had the opportunity to study the effect of the organic enrichment caused by the fish farm on meiofauna abundances and Kinorhyncha communities' structure over two farming cycles. Up to now, studies on kinorhynchs have focussed mostly on the taxonomy, biogeography, and the ultrastructure, and, more recently, on the phylogenetic aspects of the taxon. Only few studies have dealt with the ecology of these creatures and studies focusing on the response of these animals to disturbances of anthropogenic origin are rare. The study took place in the Western Mediterranean and fauna was investigated based on three replicate cores collected from eight sites: one beneath the farm, four along a transect with increasing distances from the farm, and three control sites. Density data from beneath the cage and the three control sites was analysed within a beyond-B.A.C.I. (Before-After, Control-Impact) with asymmetrical sampling design, while a Before-After approach was used to analyse data from other sites. The latter approach was applied also to investigate the environmental variables from all the surveyed sites. Overall, 21 major meiofaunal groups were found in the area, with total densities ranging from 595 to 6818ind/10cm2. We recorded a variation of the densities of several taxa after each cycle. In particular, we observed a significant increase of the total meiofauna and nematodes abundances, and a marked decrease of kinorhynchs diversity and density at the sites beneath and near the farming 'Cage'. Conversely, kinorhynch density increased at sites far from the farm. Kinorhynchs were present with ten species, including a representative of the rare genus Condyloderes, and densities up to more than 245ind./10cm2. Analyses indicate that kinorhynchs are particularly sensitive to sulfides. Accumulation of organic matter and high concentration of sulfides caused a marked reduction or even the disappearance of kinorhynchs. If confirmed by additional studies, the nematodes/kinorhynchs ratio could be used as simple and useful tool for the assessment of organic enrichment in marine environments, especially in muddy bottoms. © 2016 Elsevier GmbH.

Abbes M.,University of Sfax | Abbes M.,Consorzio Universitario Della Provincia Of Trapani | Baati H.,University of Sfax | Messina C.,University of Palermo | And 3 more authors.
BMC Complementary and Alternative Medicine | Year: 2013

Background: Bioactive molecules have received increasing attention due to their nutraceutical attributes and anticancer, antioxidant, antiproliferative and apoptosis-inducing properties. This study aimed to investigate the biological properties of carotenoids extracted from Archaea. Methods: Halophilic Archaea strains were isolated from the brine of a local crystallizer pond (TS7) of a solar saltern at Sfax, Tunisia. The most carotenoid-producing strain (M8) was investigated on heptoma cell line (HepG2), and its viability was assessed by the MTT-test. The cells were incubated with different sub-lethal extract rates, with carotenoid concentrations ranging from 0.2 to 1.5 μM. Antioxidant activity was evaluated through exposing the cells to sub-lethal extract concentrations for 24 hours and then to oxidative stress induced by 60 μM arachidonic acid and 50 μM H2O2. Results: Compared to non-treated cells, bacterial carotenoid extracts inhibited HepG2 cell viability (50%). A time and dose effect was observed, with cell viability undergoing a significant (P < 0.05) decrease with extract concentration. After exposure to oxidative stress, control cells underwent a significant (P < 0.05) decrease in viability as compared to the non-treated cells. Conclusions: The bacterial extracts under investigation were noted to exhibit the strongest free radical scavenging activity with high carotenoid concentrations. The carotenoid extract also showed significant antiproliferative activity against HepG2 human cancer cell lines. © 2013 Abbes et al.; licensee BioMed Central Ltd.

Trocino A.,University of Padua | Xiccato G.,University of Padua | Majolini D.,University of Padua | Tazzoli M.,University of Padua | And 6 more authors.
Food Chemistry | Year: 2012

The study evaluated the levels of dioxin-like polychlorinated biphenyls (DL-PCBs) and metals in the fillet of medium (468 ± 92 g) and large (708 ± 135 g) European sea bass (Dicentrarchus labrax) from 11 Italian fish farms using different rearing systems. DL-PCB contamination was higher in fish grown in extensive coastal lagoons compared with intensive inland basins and intensive sea cages (28.5 vs. 9.13 and 13.1 pg Toxic Equivalents (TEQ)/g fat; P < 0.001). Copper concentrations were lower (0.810 vs. 0.993 and 1.071 mg/kg fw) and mercury was higher (0.025 vs. 0.006 and 0.003 mg/kg fw) (P < 0.001) in sea bass from extensive farms than from intensively farmed fish in inland or sea cage systems. Sea bass size did not affect DL-PCB and metal contamination. Even at the highest contamination levels detected in this study, European sea bass were always below risk for human health concerns and were considered safe for human consumption. © 2012 Elsevier Ltd. All rights reserved.

Messina C.M.,University of Palermo | Faggio C.,Messina University | Laudicella V.A.,Consorzio Universitario Della Provincia Of Trapani | Sanfilippo M.,Messina University | And 3 more authors.
Aquatic Toxicology | Year: 2014

In this study the effects of an anionic surfactant, sodium dodecyl sulfate (SDS), are assessed on the Mediterranean mussel (. Mytilus galloprovincialis), exposed for 18 days at a concentration ranging from 0.1. mg/l to 1. mg/l. The effects are monitored using biomarkers related to stress response, such as regulatory volume decrease (RVD), and to oxidative stress, such as reactive oxygen species (ROS), endogenous antioxidant systems and Hsp70 levels. The results demonstrate that cells from the digestive gland of M. galloprovincialis, exposed to SDS were not able to perform the RVD owing to osmotic stress. Further, SDS causes oxidative stress in treated organisms, as demonstrated by the increased ROS production, in comparison to the controls (. p<. 0.05). Consequently, two enzymes involved in ROS scavenging, superoxide dismutase (SOD) and catalase (CAT) have higher activities and the proportion of oxidized glutathione (GSSG) is higher in hepatopancreas and mantle of treated animals, compared to untreated animals (. p<. 0.05). Furthermore Hsp70 demonstrates an up-regulation in all the analyzed tissues of exposed animals, attesting the stress status induced by the surfactant with respect to the unexposed animals. The results highlight that SDS, under the tested concentrations, exerts a toxic effect in mussels in which the disruption of the osmotic balance follows the induction of oxidative stress. © 2014 Elsevier B.V.

Mahdhi A.,University of Monastir | Messina C.,University of Palermo | Messina C.,Consorzio Universitario Della Provincia Of Trapani | Kamoun F.,National Institute of the science and Technologies of the Sea INSTM | And 3 more authors.
Biologia | Year: 2012

In this study, Artemia salina cysts collected from four Tunisian hypersaline environments were characterized using biometrical, biological and biochemical descriptors. Biometrical analysis revealed that the mean diameter value ranged from 220. 25 to 237. 76 μm, for the untreated cysts, from 199 to 224. 52 μm for decapsulated cysts and that the chorion thickness ranged from 6. 62 to 10. 58 μm. 48 h after hatching, Artemia from Sebkha El Meleh, Sebha Moknine, Sfax saltworks and Sahline saltworks presented a hatching percentage of 52. 7%, 53. 75%, 70. 16% and 43. 74%, respectively. The length of the freshly hatched instar I nauplii varied from 429 to 449. 34 μm. The fatty acids profile showed that the n-3 series was strongly dominant in the samples collected from Sebkha Moknine and Sfax saltworks, representing a percentage ranging from 17. 92% to 22. 45% of the total fatty acids. The data collected in this study can be useful to add new information on biological and biochemical characterization of Artemia strains present in Tunisia. On the basis of fatty acid profile, the Artemia strains collected from Sahline saltworks, Sfax saltworks and Sebkha El Meleh can be as classified as "marine" type, and that from Sebha of Moknine as "freshwater" type. © 2011 Versita Warsaw and Springer-Verlag Wien.

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