Developing an SCAR and ITS reliable multiplex PCR-based assay for safflower adulterant detection in saffron samples

Abstract

Saffron (Crocus sativus L.), one of the most important and expensive medicinal spice products traded internationally, is subject to adulteration by design or default with safflower stamens and corn stigmas, leading to poor quality of saffron samples. The present study aims at the development of specific, sensitive and reproducible PCR-based markers to detect these adulterants in traded saffron. Six putative RAPD markers generated by random primers, OPA-14, MG-11, MG-12 and AJ-05, were identified as saffron specific by comparative RAPD analysis of genuine saffron, safflower and corn. These specific RAPD markers were cloned, sequenced and six pairs of SCAR primers were designed. Specific designed primers were able to amplify reproducible saffron DNA with expected sizes and no amplification in corn and safflower DNA. In this study, a primer pair was also designed based on ITS sequences for specific amplification of safflower DNA. PCR reactions were also specifically amplified 613 bp of ITS region in safflower genome. The multiplex PCR assays were further established for the joint use of some SCAR and ITS markers efficiently. The special feature of this new molecular method was technically rapid and convenient practically and suitable for analyzing large numbers of samples. Thus, the simple rapid PCR-based molecular method could be used as a helpful assistant tool for the identification of adulterant saffron samples. This study described the development of a new SCAR and ITS maker-based multiplex PCR assay for the rapid molecular detection of substitutes in saffron.