6% of the total gonad fatty acids; the MUFA group represented 14.25% of total fatty acids.The highest levels of selleck chem Navitoclax the PUFA were found in the winter and in the spring, while the lowest occurred in the summer (P < 0.01). Eicosapentaenoic (C20:5 n ? 3, EPA), docosadienoic (C20:2), and docosatetraenoic (C20:4 n ? 3) were the major PUFA in the sea urchin gonads. EPA, which was the major compound, comprised more than 40% of the total PUFA.The seasonal variations of PUFA were primarily due to changes in C20:5 n ? 3 and C20:4 n ? 3. The fatty acid C20:2, which was proportionally the second important PUFA, did not show significant seasonal variations.The trend of changes in PUFA and SFA contents was totally opposite, with a significant reduction of the gonad SFA content during the period ranging between November and March.

The main saturated fatty acids were C16:0, C14:0, and C18:0. The pattern of changes of C16:0 and C14:0 was similar throughout the year. In the winter, the level of the C16:0 and the C14:0 fatty acids decreased to a minimum of 10.76% and 4.52%, respectively. Similarly, in the summer, those fatty acids increased progressively to a maximum percentage (17.03% and 8.17% resp.) in August. The level of C18:0 remained stable throughout the year with a mean value of 2.78%.The MUFA content was lower in the autumn and in the beginning of the summer with minimum value of 11.75% in December. Higher values of MUFA were evident in July (16.73 �� 0.78%), August (16.52 �� 1.02%), and September (17.63 �� 052%). The dominant MUFAs were C18:1 n ? 9 and the C18:1 n ? 7.

In the winter (December), the percentage of the C18:1 n ? 9 decreased to the lowest value of 3.67% and then increased progressively to the highest level of 11.49% in August. During the same period, the percentage of C18:1 n ? 7 dropped down to a minimum of 0.31%, with a percentage significantly lower (P < 0.01) than that of the C18:1 n ? 9. Between October and January, the C18:1 n ? 7 percentages remained significantly higher than that of the C18:1 n ? 9.4.6. Variation of C18:1 n ? 9/C18:1 n ? 7 RatiosIn October, the ratio of C18:1 n ? 9/C18:1 n ? 7 was 0.56 and remained around that value through November and December. In January, it increased significantly (P < 0.05; 0.66) to reach a maximum value of 36.67 in August (Table 1).5. DiscussionVarious studies have investigated different aspects of the gonad cycle in the sea urchin, Paracentrotus lividus [19�C21]. In Mediterranean population, Entinostat single annual spawning period [22] and two annual spawning periods [14, 23] have been reported. Previous studies revealed that, within the same area (Ireland), both single and double spawning may occur [24]. The current study confirmed the presence of a single annual spawning of the sea urchin P.