Detecting adulteration of Dendrobium officinale by real-time PCR coupled with ARMS

The high commercial value of Tiepi Fengdou presents the constant risk of adulteration with cheaper Dendrobium products. Therefore, a novel method, combining SYBR Green II-based real-time PCR (rt-PCR) with amplification refractory mutation system (ARMS), was established. By performing the diagnostic rt-PCR assay, a 109-bp fragment was specifically amplified from the internal transcribed spacer region of D.similar to officinale. The difference between the average cycle threshold (Ct) value of Tiepi Fengdou (20.48) and the mean of those of all reference Dendrobium products (31.83) was statistically significant (P < 0.001). The results indicate that the established system can be able to rapidly and unequivocally discriminate Tiepi Fengdou from its adulterants.