The investigation of changes in sexual and seasonal variation in proximate composition and tetrodotoxin (TTX) levels in puffer fish (Lagocephalus sceleratus) caught from Mersin gulf

In this study, changes of sexual and seasonal variation in proximate composition and fatty acid profile of puffer fish (Lagocephalus sceleratus) caught from Mersin Gulf during the period of December 2012 and November 2013 were investigated. Changes in the levels of tetrodotoxin (TTX) of gonads, liver and muscle depending on season and sex were also investigated. The samples used seasonally were caught by bottom trawl, longline and fishing line. Nutritional composition analysis showed that the average protein, lipid, moisture and ash content for males were 20.44%, 0.65%, 76.98%, 1.43% and for female individuals were 20.58%, 0.87%, 77.12%, 1.4%, respectively. In terms of fatty acid analysis, 21 different fatty acids have been identified in the muscle of puffer fish. During all four seasons, fatty acids were found as palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1ω9), vassenic acid (C18:1 ω 7), linoleic acid (C18:2 ω 6), arachidonic acid (C20:4ω6), docosadienoic acid (C22:2 cis), eicosapentaenoic acid (EPA, 20:5ω3) and docosahexaenoic acid (DHA, 22:6ω3). The highest TTX levels in female fish were detected in their gonads in the winter season following by fall season. In the male gonads, TTX levels were higher than 10 MU/g only in the autumn season. TTX levels were higher than 10 MU/g in liver of winter and summer female individuals. Although muscle extract of puffer fish that is injected to mice has shown poisoning symptoms of TTX, death of mice was not observed and TTX level was less than 5 MU/g.