Identification of sheep (Ovis aries) meat by alkaline lysis-loop mediated isothermal amplification technique targeting mitochondrial D-loop region

Abstract

Identification of meat species origin using reliable techniques is a critical requirement for ensuring label compliance, protection of consumer preference and prevention of fraudulence in the meat trade. Although a plethora of protein and DNA based meat species identification techniques are in vogue, need for rapid test suitable for under-resourced laboratories catering point-of-care (PoC) services was construed. Present study deals with development of rapid sheep (Ovis aries) meat identification technique using DNA extraction by alkaline lysis (AL) and loop-mediated isothermal amplification (LAMP) technique. The AL–LAMP specifically amplifies sheep-specific signal of mitochondrial D loop region under an isothermal temperature of 60 °C with an analytical sensitivity of 0.5 ng sheep DNA. The test was highly specific to sheep and performed well even in the presence of DNA of closely related meat animal species such as goat, cattle, buffalo and chicken. The novel primers designed for the AL–LAMP successfully detected sheep meat in raw and cooked meat samples heated up to 121 °C for 30 min. Sheep-specific AL–LAMP assay could detect 0.1% mutton-in-beef adulteration. Novel AL–LAMP assay being simple, rapid and reliable for sheep meat authentication in just 120 min; hence, it could be conveniently used by terminal laboratories engaged in rendering on-site or PoC services.