Authentication of sea cucumber products using NGS-based DNA mini-barcoding

Sea cucumbers are widely consumed in Asia. This study developed a novel DNA mini-barcode mitochondrial cytochrome c oxidase (COI) of 257 bp to discriminate sea cucumbers species in both raw and processed forms. We designed and compared four mini-barcoding primer sets based on PCR amplification rates against 40 authenticated sea cucumber species. The top-performing primer set was successful for most tested sea cucumber varieties. We also tested the DNA mini-barcode COI in 12 highly processed sea cucumber products using both Sanger sequencing and next-generation DNA sequencing (NGS). This is the first report of highly processed sea cucumber products that detected fraudulent replacement of sea cucumber by one or a blend of species using the NGS approach. The established DNA mini-barcoding system revealed that 83.33% (10/12) of highly processed sea cucumber products were mislabeled. This study identified a need for more regulation of the sea cucumber trade and suggested that DNA mini-barcoding combined with NGS could complement existing sea cucumber identification strategies.