Evaluation of a Rapid PCR-Based Method for Species Identification of Raw and Processed Fish and Shrimps

Abstract

The increase of mislabeled seafood and illegal fisheries demands rapid methods to control fishery products. We have tested a rapid deoxyribonucleic acid (DNA) extraction and amplification method to identify raw and processed fish and shrimp using polymerase chain reaction (PCR)-based techniques. The KAPA Express Extract Kit delivered DNA from raw, cooked, canned, and marinated products that was suitable for mutation detection. Segments of mitochondrial genes, sized from 123 to 464 base pairs (bp), were amplified by PCR kits from two vendors. Amplicons of raw fish fillets were differentiated by single strand conformation polymorphism (SSCP) analysis, raw or cooked shrimps were analyzed by restriction fragment length polymorphism (RFLP), and the PCR product obtained for marinated herring was sequenced. The extracted DNA was not degraded during storage in the refrigerator for about 1 week or in the freezer-cabinet for 1 month.

Keywords:

• fish
• shrimp
• rapid PCR
• KAPA

Acknowledgments

The authors would like to thank Ron McEwan and Ross Wadsworth at KAPA BIOSYSTEMS for advice and support of this study. Gratitude is expressed to Alexandra Oliveira and Gabi Näumann for providing authenticated fish samples. The skillful technical performance of experiments by Roswitha Koch and Rainer Kündiger is gratefully acknowledged.