2025/04/15 by Hongchen Zhu, Junji Takeoka, In Sokra +10
Environmental Science · Earth and Planetary Sciences · Biochemistry, Genetics and Molecular Biology · #Marine Toxins and Detection Methods #Marine Invertebrate Physiology and Ecology #Marine Sponges and Natural Products
paper · doi:10.1016/j.toxicon.2025.108363
The Mekong River in Cambodia is inhabited by approximately ten species of freshwater pufferfish of the family Tetraodontidae. However, limited information is available regarding the toxin profile of these fish. In this study, to obtain sufficient information on the intra-body distribution of toxins in Cambodian freshwater pufferfish, one species of Pao freshwater pufferfish ( Pao sp. A) were collected from Phnom Penh (PNH) in November 2019 (n = 23) and from Kratie (KTI) in March 2023 (n = 21). Toxin analyses of these samples revealed that individuals from both regions possessed saxitoxins (STXs) and contained no tetrodotoxin. Pao sp. A specimens from PNH possessed high STXs levels in the skin, muscle, liver, and gonads, whereas those from KTI showed relatively low levels of STXs concentrated in the skin. STXs amount in the ovaries in PNH individuals increased exponentially with increasing the gonadosomatic index (GSI). We also clarified that STXs concentration in the skin became increasingly higher as KTI individuals grew. These results suggest that differences in living regions may affect the intra-body distribution of STXs in Pao freshwater pufferfish, with maturation and/or growth contributing as well. • A freshwater pufferfish of the genus Pao from Cambodia contained saxitoxins (STXs) and was unsuitable for consumption. • The intra-body distribution of STXs in this species had regional differences. • STXs in the ovaries in individuals collected from Phnom Penh (PNH) increased exponentially with increasing GSI. • STXs concentration in the skin increased linearly as individuals collected from Kratie (KTI) grew.