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In this research, in situ generated ozone exposure/wash cycles of 1, 3, and 5 min applied to shrimp samples either before (BIS) or during iced storage (DIS) has been used to study the lipid oxidation kinetics using the peroxide values (PV). The induction period (IP) as well as PV at end of the IP (PV IP ) have been obtained. The rate constants ( k ) as well as half-lives ( t 1/2 ) of hydroperoxides formation for different oxidation stages were calculated. The results showed that both IP and PV IP were lower with BIS (IP between 4.35±0.09 and 5.08±0.23 days; PV IP between 2.92±0.06 and 3.40±0.18 mEq kg −1 ) compared with DIS (IP between 5.92±0.12 and 6.14±0.09 days; PV IP between 4.49±0.17 and 4.56±0.10 mEq kg −1 ). The k value for DIS seemed to be the greater compared to BIS. In addition, whilst decreases and increases in t 1/2 were found at propagation, respectively, for BIS and DIS, decreases and increases were only found at the induction of oxidation stage(s) for BIS. Further, the PV of ozone-processed samples would fit first order lipid oxidation kinetics independent of duration of ozone exposures. For the first time, PV measurements and fundamental kinetic principles have been used to describe how increasing ozone exposures positively affects the different oxidation stages responsible for the formation of hydroperoxides in ozone-processed shrimp.

Plastics are widely diffused in the oceans and their ingestion by marine organisms is raising concern for potentially adverse effects. The risk of harmful interactions with marine plastic pollution depends on the biology of the species as well as the distribution and abundance of the different plastic types. The aim of this study was to assess the occurrence of plastic ingestion by the small-spotted catshark (Scyliorhinus canicula), one of the most abundant elasmobranchs in the Mediterranean Sea. The expression levels of genes indicative of total immune system function were analyzed to gather preliminary data for further investigation of any potential correlations between plastic presence and immune activation. One hundred catsharks were collected during the Spring 2018 in two geographic locations in the southern region of the central Mediterranean Sea: 1) near Mazara del Vallo, SW Sicily and 2) near Lampedusa island, Italy's southernmost. Standard measurements were recorded for each specimen and its organs and sex was determined. The gastrointestinal tract (GIT) was preserved for plastic detection and identification. Where present, plastics (macro- and micro-) were characterized in terms of size, shape and polymer typology through microscopy and μ-Raman spectroscopy. Spleen from a subset of thirty samples was preserved for RNA extraction, then used to quantify by real time PCR the transcripts of T cell receptor beta (TCRB), T cell receptor delta (TCRD) and IgM genes. The results indicated that ingestion of plastic is widespread, with microplastics (MP, from 1 μm to 1 cm) in approximately 18% of the specimens collected. A significant increase in the expression of TCRB, TCRD and IgM was observed in the spleen of MaP + specimens from Mazara del Vallo waters, in parallel with 67% increase in liver weight. While the presence of MP alone is not enough to induce a strong activation of the immunity, some type of plastics falling into the MaP category may be more toxic than others and crucial in the activation of the immune response. The results of this study represent a first evidence that plastic pollution represents an emerging threat to S. canicula, the Mediterranean food web and human consumers.

An unusual catch of mature specimens of Pagellus acarne (Risso, 1827) off the south coast of Sicily (Quadro Bank, central Mediterranean Sea) on October 2016 allowed to improve the ongoing knowledge on the age structure of spawners and other reproductive aspects of the species. A sample of 104 (32 female and 72 male) specimens was examined. Females showed size (range TL 1 = 20.5 to 25.5 cm; mean length = 22.3 ± 1.2 cm) longer than males (range TL = 16.5 – 23.5 cm; mean length = 20.0 ± 1.8 cm). About 94% of females and 88% of males were mature. The pooled sex LWR 2 was W 3 (g) = 0.003 TL 3.5207 . The age structure estimated by sagittae readings ranged from age class III to VII in females and II to VI in males with a prevalence of age class VI and IV for females and males, respectively. The precision of age estimates was tested by applying both the APE 4 and the mean CV 5 . Our record suggests that the Quadro Bank is an EFH 6 for P. acarne. Knowing when and where adults aggregate for reproduction, is a prerequisite to develop effective management measures to preserve the replacement capability of exploited stocks and pursue sustainable fisheries strategies.