Species identification of fish maw (Porcupinefish) products sold on the market using DNA sequencing of 16S rRNA and COI genes

Fish maws have been commonly recommended and consumed as delicacies, medicine and tonics in Asia over many centuries. However, the true species of the fish maws in the trade is unknown. It is difficult to identify the fish species just based on their morphological characters of swim bladders. In this study, 96 fish maw products commercialized in the market were analyzed in order to authenticate species. Direct sequencing method based on fragments of the 16S rRNA gene and COI gene were carried out and results showed that the fish maw were extracted from porcupinefish. 53 products were Diodon liturosus, 40 products were Diodon hystrix and three products were Chilomycterus reticulates. Therefore, this work facilitates the identification of fish maw products in the market, support of food control and protection of consumers' rights. Moreover, based on the previous toxicity reports, it is suggested that the Spot-fin porcupinefish D. hystrix maw exists potential food security threat to the consumers.