Detection and identification of marine fish mislabeling in Guangzhou's supermarkets and sushi restaurants using DNA barcoding

Abstract

In this study, DNA barcoding was applied to identify the distinct species of fish products in Guangzhou supermarkets and sushi restaurants in order to confirm whether products were correctly labeled. Samples were analyzed using mitochondrial cytochrome C oxidase subunit I (CO I) gene as the target. Our results showed that the CO I gene of all 139 samples examined was successfully amplified by PCR. When sequenced, 30 samples (21.58%) were mislabeled as the wrong species, 11 samples had insufficient information provided on the label to determine if the labeling was correct (7.91%), and four samples failed sequencing (2.88%). We also found that the use of proper labels for fish products in sushi restaurants was higher than that in supermarkets. As a simple, rapid, and efficient technology, DNA barcoding can be widely used for species identification of fish products. Our work shows that regulation of the labeling of fish products, as we evaluated in Guangzhou and other markets in China, is needed on a global scale.

Analysis of Whole-Genome as a Novel Strategy for Animal Species Identification

“…It is evident that discrepancies between product labels and actual test results, as well as product adulteration, are common in the tested samples. It is no coincidence that product quality issues were also found in commercially available herbal products [ 51 ], fish products [ 52 ], and in the food service industry [ 53 ]. To safeguard consumer rights and avoid the risk of violating certain religious and/or cultural strictures, AGE provides accurate identification of species and enables effective control of the production and distribution of goods.…”

Morphological Development and DNA Barcoding Identification of Pholis fangi Larvae and Juveniles in the Yellow Sea

“…The PCR reaction mixture totaled 50 µL, comprising 5 µL of 10× PCR buffer, 4 µL of dNTPs (2.5 mmol/L), 2 µL ofeach primer (10 mmol/L), 0.8 µL (5 U/µL) of Taq DNA polymerase, 1 µL of template DNA, and 35.2 µL of distilled water. Amplification was performed on an AG-22331PCR system (Eppendorf) with the following protocol: an initial denaturation at 94 • C for 5 min; 35 cycles of 94 • C for 30 s, 52 • C for 45 s, and 72 • C for 1 min; followed by a final extension at 72 • C for 10 min, and storage at 4 • C. The amplification products were verified using 1.0% agarose gel electrophoresis and subsequently sequenced by Shanghai Jieli Biotechnology Co., Ltd., Shanghai, China [14][15][16].…”

“…Subsequently, all sequences were compared and aligned Clustal X, with redundant sequences at both ends being removed. Effective COI gene sequences underwent BLAST analysis in both the Barcode of Life Data System (BOLD) database and GenBank databases to facilitate species identification [15]. These sequences were further aligned and edited in MEGA7 software.…”

“…Due to limited information, traditional morphological identification restricts not only species identification but also the understanding of larval and juvenile stages in many fish species. Molecular technology overcomes the bottleneck in larval and juvenile species identification [14][15][16][17][18], enabling a broader understanding of species diversity. This study combined DNA barcoding with dynamic research methods to identify species at various stages and sizes.…”

DNA Barcoding Is a Useful Tool for the Identification of the Family Scaridae in Hainan

“…Fragments of the mitochondrial COI gene were amplified using the following universal fish barcoding primers: forward fish-F 5 -TCRACYAAYCAYAAAGAYATYGGCAC-3 and reverse fish-R 5 -ACTTCAGGGTGACCGAAGAATCAGAA-3 . The total volume and thermal cycle sequences of the PCR were performed as described previously [35]. The amplified PCR products were checked for optimal fragment sizes on 1.5% agarose gels.…”