Seasonal, body weight and gender variation of tetrodotoxin in horseshoe crab Carcinoscorpius rotundicauda collected from Can Gio coast, Ho Chi Minh city, Vietnam

Abstract

Liquid chromatography–mass spectrometry (LC-MS/MS) was used for measurement of the variation of tetrodotoxin (TTX) in a horseshoe crab Carcinoscorpius rotundicauda collected from Can Gio coast, Ho Chi Minh City, Vietnam from May 2021 to May 2022 over the seasons, body weight and gender. The data revealed that there was significant variation of TTXs level over the months with maximal TTXs toxicity determined of 197.6 ± 134.5 MU/g for specimens collected in May 2021, whereas the C. rotundicauda collected in January 2021 was found to yield minimum TTXs level of 7.8 ± 8.4 MU/g. Interestingly, the difference of TTXs level in different body-weight C. rotundicauda groups was also statistically significant, with maximal TTXs toxicity of 230.3 ± 116.3 MU/g determined for specimens having body weight of greater than 300 g, while the lowest level of TTXs (9.8 ± 12.3 MU/g) was assayed for C. rotundicauda group of body weight less than 150 g. Moreover, there was a significant difference in TTXs levels among female and male C. rotundicauda groups, with notable higher TTXs toxicity determined for female specimens (123.9 ± 45.8 MU/g) than that of male C. rotundicauda (68.7 ± 45.8 MU/g). In particular, the average level of TTXs of 96.3 ± 94.2 MU/g measured in all studied crabs indicated that they are unsafe for human consumption. Fortunately, horseshoe crab collected from Can Gio coast, Ho Chi Minh City, Vietnam is a promising source for isolation and purification of tetrodotoxin for other applications (e.g., drug).