Different origins of Gastrodia elata: Comparative study of FT-NIR characteristics and polyphenol components

Gastrodia elata (GE) serves both edible and medicinal purposes. This study employed fourier transform near-infrared (FT-NIR) technology to preliminarily analyze the chemical components of GE from 9 different geographical origins. The results showed that the spectral profiles of samples from Yunnan were distinctly different from those of Hubei and Guizhou. Phenotypic analysis based on L*, a*, and b* parameters further revealed differences in appearance traits, with results similar to the spectral characteristics obtained through principal component analysis (PCA), indicating a certain correlation between external traits and internal chemical components. To further uncover chemical compositional differences, non-targeted metabolomics using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) identified 810 polyphenol metabolites, including 257 differential metabolites (P < 0.05, VIP > 1), covering phenolic acids, flavonoids, lignans and coumarins, and tannins. Correlation analysis between traits and metabolites showed that a* and b* were significantly negatively correlated with phenolic acids and flavonoids (P < 0.05 or P < 0.01), while L* was significantly positively correlated with flavonoids (P < 0.05 or P < 0.01). Additionally, the study indicated that temperature and humidity are key environmental factors affecting the synthesis and accumulation of metabolites in GE.