Application of DNA technique for identifying the species of different processed products of swordfish meat

Abstract

Polymerase chain reaction technology and sequence analysis were used to identify the species in fresh, frozen, cooked, sterilized, and dressed dried fried meat of swordfish Xiphias gladius. The specific primers L-HS I, II, III, and IV, in conjunction with H-CSBDH, produced 357-, 238-, 137-, and 87-bp fragments, respectively, in the control region of swordfish mitochondrial DNA, but not for other billfish. These fragments were useful for detecting the species used in processed products claiming to be X. gladius. The primers L-HS IV and H-CSBDH produced 87-bp mtDNA fragments to identify the species of dressed dried fried swordfish meat products. Using L-HS IV and H-CSBDH primers’gene fragment to judge, it was found that only 45.8% (11/24) commercial samples of dressed dried fried products were made from swordfish.