Nutritional composition and FT-IR functional group analysis of pharaoh cuttlefish (Sepia pharaonis) from Puducherry coastal waters, India

The nutritional composition and functional groups of the edible portion of the most often utilized cuttlefish, Sepia pharaonis of Puducherry coastal waters, India was evaluated. Moisture is the basic component of the mantle with 82.45±0.15% followed by a good source of 14.5±0.1% protein. The ash, lipid, and carbohydrates were found less than 1%. The energetic value of the mantle of cuttlefish S. pharaonis is calculated as 6.06 KJ/g. Na and K were found in considerable quantities of 2772 and 3247 mg/kg respectively and the Na/K ratio (0.85) was less than 1. The amount of Zn, Mn, B, Al, Sr, and As was found to be relatively high when compared to a low or insignificant level of Cu, Mo, Se, Cr, Ni, Pb, and Hg. The fatty acid profile analysis revealed that it contains 71.67% saturated fatty acids,17.87% polyunsaturated fatty acids and 10.38% monounsaturated fatty acids. In all three types, the C16:0 palmitic acid (40.29%), C18:0 stearic acid (16.54%), and C22:6 docosahexaenoic acid (13.52%) represented as the dominant fatty acids. The FT-IR analysis disclosed the presence of various functional groups belonging to protein, lipids, and polysaccharides. Thus, the present study proved that the cuttlefish S. pharaonis is considered as a potential nutraceutical and the right choice of food for greater and wider human consumption.

Pharaoh Cuttlefish, Sepia pharaonis, Genome Reveals Unique Reflectin Camouflage Gene Set

Sepia pharaonis, the pharaoh cuttlefish, is a commercially valuable cuttlefish species across the southeast coast of China and an important marine resource for the world fisheries. Research efforts to develop linkage mapping, or marker-assisted selection have been hampered by the absence of a high-quality reference genome. To address this need, we produced a hybrid reference genome of S. pharaonis using a long-read platform (Oxford Nanopore Technologies PromethION) to assemble the genome and short-read, high quality technology (Illumina HiSeq X Ten) to correct for sequencing errors. The genome was assembled into 5,642 scaffolds with a total length of 4.79 Gb and a scaffold N50 of 1.93 Mb. Annotation of the S. pharaonis genome assembly identified a total of 51,541 genes, including 12 copies of the reflectin gene, that enable cuttlefish to control their body coloration. This new reference genome for S. pharaonis provides an essential resource for future studies into the biology, domestication and selective breeding of the species.