PCR-Based Method for Authentication of Meat and Processed Meat from Three Commercially Important Catfish Species

Meat in forms of fresh-cut pieces or fillet or processed meat from broadhead catfish (Clarias macrocephalus), African catfish (Clarias gariepinus), and black eel-tail catfish (Plotosus canius) shares similarity in appearance and texture. This may easily cause the adulteration or substitution between these three species. This problem is related with mislabeling for illegal benefits. The polymerase chain reaction (PCR)-based authentication method was then established to tackle such a problem. Three pairs of primers were designed based on cytochrome c oxidase (COI) gene for each catfish using PrimerExplorer. The specificity toward seven other freshwater fish species and the sensitivity using 0.7-50 ng of positive DNA were further tested. The results showed that all primer pairs specifically amplified the responsible DNA and had the limit of detection at 0.7 ng for all catfish species tested. The processing methods, including boiling, frying, and steaming, did not affect the efficiency of the PCR amplification. Therefore, this procedure could be applicable for species identification or adulteration among all three catfishes.