Multiuse of Bar-HRM for Ophiocordyceps sinensis identification and authentication.

Bar-HRM is a hybrid method which combines DNA barcoding and High Resolution Melting analysis. It has proven to be a fast, cost-effective and reliable molecular approach for species identification and authentication. Here, three aspects of the use of Bar-HRM are focused on. First, Bar-HRM is used to discriminate between closely related Ophiocordyceps species. Second, identification of an unknown powder that is claimed to be Ophiocordyceps species using Bar-HRM. Third, authenticating the O. sinensis products sold on the market by the Bar-HRM. Results from HRM analyses with ITS primers shows that the two Ophiocordyceps species (Ophiocordyceps sinensis and Ophiocordyceps militaris) were easily differentiated. Also, an unknown sample was able to be identified in less time compared with using DNA barcoding alone. In addition, the substitution or adulteration of O. sinensis products sold on market was detected via Bar-HRM. The substitution or adulteration of inferior Ophiocordyceps species, particularly O. militaris in high price O. sinensis products has been a concern throughout Asia. Based on our results, the Bar-HRM was again proved to be a promising tool for species identification and authentication.