Detection of tilapia, salmon, shark and shrimp in gelatin products by PCR method for the first time in Iran

Gelatin is made from the collagen of the skin and bones of animals and is widely used in food, pharmaceutical, cosmetics. Given the importance of the halal status of gelatin used in these products, the production and supply of halal gelatin are important in terms of global trade. Today, the solubility of gelatinous products is controlled for the origin of pigs or cattle, but in cases where the capsules or supplements are from fish and aquatic gelatin, they are not detected. Specific primers for tilapia, salmon, sharks and shrimp were designed using databases and Bioinformatics studies. Then the PCR method was optimized. Finally, the DNA extracted from the capsules, collagen and supplements were amplified with specific primers and displayed on agarose gel. PCR reaction with specific primers of tilapia, salmon, shark and shrimp showed 113, 122, 200 and 132 bp bands on agarose gel, respectively. The specificity, stability and repeatability of the method were confirmed for each pair of primers. PCR with DNA extracted from gelatin and collagen capsules also confirmed the origin of aquatic animals. In this study, for the first time, the origin of collagen and gelatin capsules were identified using specific primers of tilapia, salmon, shark and shrimp and PCR. The results showed that specific primers are able to amplify the expected band and identify the source. Therefore, with this method, the solubility of the mentioned cases can be checked, approved or rejected in a short period of time before entering the country.