Abstract:To establish a multiple identification method of animal species in meat by using a universal molecular beacon with probe melting curve analysis. Through multi sequence alignment of the genomes of 9 common edible livestock and poultry, the gene fragments with specific structure in the 16S rDNA of the mitochondrial genome were selected as the detection target sequence. A pair of primers and a long-chain molecular beacon for universal detection were designed by the method of bioinformatics analysis. The characteristic annealing temperature (Tm) of different animal derived components was determined based on real-time polymerase chain reaction (RT-PCR) and melting curve analysis, while the sensitivity and specificity of the identification method were investigated. The RT-PCR based on universal primers and molecular beacon was performed on genome samples derived from 9 animal species. The amplified product of each sample was single, and the sequencing result was consistent with its reference sequence. While a dilution range of 108 to 101 copies/μL of standard DNA of pork was used as template, the RT-PCR was performed validly with incremental Ct value from 15 to 36 cycles, and the characteristic Tm was about (68.0±0.1) ℃ steadily by melting curve analysis. The detection result also showed that identifiable specific annealing temperature was obtained for each sample derived from the livestock and poultry meat investigated with Tm of 68.0 ℃ for pigs, 64.3 ℃ for cattles, 65.1 ℃ for sheep, 65.8 ℃ for donkeys, 63.4 ℃ for horses, 60.6 ℃ for camels, 61.8 ℃ for dogs, 52.6 ℃ for chickens and 56.7 ℃ for ducks. While the mixed genome derived from different animal species was detected, the results could show the independent melting peaks of various species genes or the emergence of a new fusion peak. The RT- PCR detection method based on universal primers and molecular beacon can realize the single-tube multiple identification of common livestock and poultry meat food species with ideal sensitivity and specificity. With high application value, this method could be used in meat adulteration screening.