Authentication of the Botanical Origins of Curcumae Radix Based on DNA Barcoding and HS-GC-IMS

As a classic multiorigin herbal medicine, the precise authentication of Curcumae Radix (Yujin) is crucial for ensuring market standardization and clinical efficacy. Given the complexity of herbal materials, single-method identification often lacks the resolution required to distinguish between closely related species or handle degraded with significant DNA degradation.

A two-dimensional analytical strategy was applied to 24 batches of Curcumae Radix samples. This approach combined ITS2 DNA barcoding for genetic identification with headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) to analyze volatile organic compound (VOC) profiles. The resulting HS-GC-IMS data were processed using chemometric tools, including principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA), to compare and differentiate the decoction pieces.

The results demonstrated that while ITS2 DNA barcoding effectively identified Curcuma kwangsiensis S. G. Lee et C. F. Liang, it failed to discriminate between the closely related species Curcuma longa L. and Curcuma phaeocaulis Val. and was ineffective for DNA-degraded samples of Curcuma wenyujin Y. H. Chen et C. Ling. Conversely, HS-GC-IMS successfully established distinct VOC fingerprints for each source. When coupled with chemometric analysis, this method pinpointed specific interspecific discriminatory biomarkers that allowed for clear differentiation where genetic barcoding fell short.

By integrating stable genetic information with volatile chemical fingerprints, this study establishes a complementary two-dimensional identification system. This strategy provides an innovative and reliable solution for the botanical authentication and quality control of Curcumae Radix, offering a broadly applicable paradigm for the precise identification of other complex herbal materials.