Nutritional values vs. Toxicity assessment of pufferfish, Tetraodon lineatus (Linnaeus, 1758), from Lake Nasser, Egypt

The nutritional value versus toxicity was conducted in muscles, gonads, livers, and skin of Tetraodon lineatus from Lake Nasser, Egypt, during 2018. Its overall moisture was 74.92 ± 2.27 muscles, 72.45 ± 2.887 gonads and 35.49 ± 5.55 % livers. The livers recorded the highest crude protein (23.66 ± 3.48%) and total lipids (36.45 ± 6.32%). The annual total protein in muscles was 16.91 ± 2.54%, while the annual total lipids were 3.39 ± 1.05 %. Leucine was the most abundant (0.548 mg/g) ˃ isoleucine (0.284 mg/g) of the essential amino acids. Sixteen fatty acids were recorded (12: SFAs, 4: MUSFAs), with butyric acid predominating. Assessment of tetrodotoxin (TTX) as mouse per unit (MU/g), gave the highest toxic abundant for skin (53.13%) ˃ gonads (34.6)  ˃ muscles (12.9) and no detection in the livers. The average toxicity in all organs is at a low level and lower than the maximum permissible limits (<100 MU/g) despite strongly toxic samples. The abundance of all toxic samples was in summer (44.8%) and spring (36.8), followed by winter and autumn (9.2 each one). Muscles, gonads, and livers showed no response to toxicity tests during winter. On the contrary, muscles were highly contaminated with TTX in summer (25%) and spring (22.2). The findings confirmed that T. lineatus has a good nutritional value, toxicity restrictions in specific organs and seasons, recommending its better utilization with more studies to confirm its safety for human consumption.