Identification of the geographical indication origin of Gastrodia elata Blume based on FT-NIR spectroscopy

Abstract

The Yunnan Zhaotong G. elata has high attached edible and medicinal value and has been protected by geographical indication (GI). However, for different G. elata variants, Gastrodia elata Bl. f. glauca S. Chow (GB) exhibits quality characteristics superior to other variants. In different growing conditions, wild G. elata typically displays superior quality characteristics compared to cultivated G. elata. Therefore, accurate certification of origin and variety is a prerequisite for protecting consumer interests. In this framework, we analyzed 418 FT-NIR regional spectra of G. elata. FT-NIR spectroscopy combined with principal component analysis (PCA), binary and multi-class partial least squares discriminant analysis (PLS-DA), and data-driven soft independent modeling of class analogy (DD-SIMCA) techniques were used to discriminate and authenticate Yunnan GI G. elata and distinguish it from wild G. elata. The results showed that PCA was only able to distinguish the Gastrodia elata Bl. f. elata (GR) from the Hanzhong, Shaanxi. For multi-class PLS-DA, it is possible to distinguish wild G. elata and Gastrodia elata Bl. f. viridis (Makino) Makino (GG) from the Hezhang, Guizhou. The binary PLS-DA was able to differentiate between Yunnan GI G. elata and non-Yunnan G. elata as well as GB and Non-GB in Yunnan GI G. elata with 100 % sensitivity and specificity. In addition, DD-SIMCA also verified the reliability of the method. Thus, the method is objective, simple, rapid and can be used for routine analysis of G. elata to verify the identity, species and origin statement of G. elata.