Being the third-largest primate population has not made macaque (Macaca fascicularis sp.) monkeys less exposed to threats and dangers. Despite wildlife protection, they have been widely hunted and consumed in several countries because of their purported nutritional values. In addition to trading as pure bush meats in several places, monkey meat has been sold in meatball and soup products in Indonesia. Thus the possibility of macaque meat trafficking under the label of common meats is quite high. This paper reports the development of a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay with the shortest amplicon length for the confirmed detection of monkey meat under compromised states which are known to degrade DNA. We amplified a 120-bp region of d-loop gene using a pair of macaque-specific primers and confirmed their specificity for the target species through cross-challenging against 17 different species using a 141-bp site of an 18 S rRNA gene as an endogenous control for eukaryotes. This eliminated the possibilities of any false-negative detection with complex matrices or degraded specimens. The detection limit was 0.00001 ng DNA in a pure state and 0.1% of meat in mixed matrices and commercial meatball products. RFLP analysis further authenticated the originality of the PCR product and distinctive restriction patterns were found upon AluI and CViKI-1 digestion. A micro-fluidic lab-on-a-chip automated electrophoretic system separated the fragments with high resolution. The assay was validated for screening commercial meatball products with sufficient internal control.

The macaque (Macaca fascicularis) monkeys are the third largest primate population in tropical forests. Being the potential carrier of Simian Immunodeficiency and Ebola and Corona viruses, as well as being a religiously-protected and wildlife-protected species could not save the macaques from being over-hunted and consumed. Despite having needs, methods to detect monkey species in foods are rarely documented. To fill this gap, this article describes a monkey-specific polymerase chain reaction assay targeting a short-site (120 bp) of mitochondrial d-loop gene because the short-length targets are thermodynamically more stable than the longer ones under degrading states. Specificity was tested against 17 terrestrial and aquatic meat and fish species and no cross-species amplification was detected under raw, processed, and admixed states. The sensitivity of the assay was 0.0001 ng DNA under pure states and 0.1% monkey meats in binary meat mixtures. Finally, the assay was validated by digesting the polymerase chain reaction products with AluI and CViKI-1 and distinctive restriction fingerprints for macaque species were demonstrated.