Lipid class and fatty acid composition of Whiteleg shrimp, Penaeus vannamei (Boone, 1931) reared in a wide range of water salinities

Abstract

Penaeus vannamei were reared at six different water salinities (3, 10, 20, 30, 40 and 50‰) for 45 days to explore its effect on lipid class and fatty acid composition. The results revealed that the total lipid content was high (p< 0.05) at 30‰ (3.14%), and low (p< 0.05) at 20‰ (2.15%). Both phospholipids and cholesterol were found to be high (p< 0.05) at 40‰ (1.30% and 0.38%, respectively), while it was at 30‰ for triacylglycerides (0.71%). A higher correlation coefficient was observed for phospholipids (R2 = 0.5975) with rearing salinity and triacylglycerides (R2 = 0.8487) with total lipid. A total of saturated fatty acids (SFA), mono unsaturated (MUFA) and polyunsaturated (PUFA) fatty acids was increased in all treatments compared to ambient salinity (20‰), and the increase was quite high with 30‰ (38.83,% 37.07% and 48.76%, respectively), whereas it was 17.47%–24.94% in SFA, 7.85%–26.05% in MUFA and 20.69%–33.82% in PUFA at hypo (3–10‰) and hyper (40–50‰) saline conditions. The correlation coefficient determinant was high for MUFA (R2 = 0.8682) followed by SFA (R2 = 0.7370) and PUFA (R2 = 0.6542) against total lipid, whereas it was much less (R2 = 0.0402–0.0588) when performed against water salinity. The daily value of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) was >100%, and was ranged between 2.81% and 3.24% for α-linolenic acid (ALA). The results concluded that the rearing salinity had a significant effect on lipid class and fatty acid composition in P. vannamei and their deposition was quite high in the group reared at 30‰.