Study on Quality Evaluation of Tibetan Dracocephali tangutici Herba Based on DNA Barcode and HPLC Fingerprinting

Objectives: The quality of 30 batches of the Tibetan Dracocephali tangutici Herba was evaluated using HPLC fingerprinting and DNA sequences.

Methods: Botanical identification of 30 batches of D. tangutici herba was conducted using the DNA barcoding approach, specifically analyzing the ITS and rbcL sequences. HPLC fingerprints of Tibetan Dracocephali tangutici Herba were established. The quality of 30 batches of D. tangutici herba was comprehensively evaluated using principal component analysis (PCA), orthogonal partial least squares discriminant analysis (OPLS-DA), and entropy weighting method (EWM) combined with grey relation analysis (GRA).

Results: The botanical provenance of all 30 batches of herbs was proven to be Dracocephali tangutici Maxim. using DNA barcoding techniques, namely, ITS sequence and rbcL sequence testing. A total of 17 common peaks were chosen from the HPLC fingerprinting analysis. Among these, three peaks were recognized by comparing them with three reference standards: chlorogenic acid, cryptochlorogenic acid, and salvianolic acid B. The similarity scores of the 30 batches of D. tangutici herba varied between 0.846 and 0.991. The 30 batches of samples were categorized into two groups using PCA. The findings from OPLS-DA indicated that chlorogenic acid and four flavonoids could be the crucial components for evaluating the quality of D. tangutici herba. Additionally, the combined evaluation results of EWM and GRA suggested that the quality of the 30 batches of samples varied significantly.

Conclusion: The results of this study can provide a reference basis for the development of quality standards for D. tangutici herba in Tibet.