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Daodi medicinal materials (DMMs), with unique characteristics and specific ecological growing environments, are recognized as high-quality medicinal products of Chinese medicinal materials (CMMs). The quality evaluation of CMMs is fundamental for standardization. The concept and application of DMMs have a long history as described in records in ancient books and rooted in practice and experience over generations. DMM is the specific term for pure, superior medicinal herbs with the following characteristics: optimum harvest season (reflecting the appropriate developmental stage of the plant), scrupulous processing, traditional preparation technology, etc. As DMM and high-quality medicinal products are traditionally thought to be closely related, modern scientific studies that confirm the association of these products are described. This article aims to clarify the scientific elucidation of DMMs.

In this study, we aim to determine the chemical constituents of six Chinese medicinal materials from the Citrus genus using high‐performance liquid chromatography and high‐resolution mass spectrometry. Eight flavonoids and one coumarin were identified and further quantified as marker substances by high‐performance liquid chromatography method. The separation was performed on an Agilent TC‐C18 column with 0.1% formic acid and acetonitrile as the mobile phase under gradient elution. The analytical method was fully validated in terms of linearity, sensitivity, intra‐ and inter‐day precision and repeatability, limit of detection, limit of quantitation, and recovery. It was subsequently applied to evaluate the quality of 103 batches of the Chinese medicinal materials from the Citrus genus. In addition, the principal constituent analysis was used to compare the samples of different species from the Citrus genus leading to successful classification of the samples in accordance with their origins. It was found that the contents of nine constituents varied greatly in different ripening stages and varieties of the samples from the Citrus genus. In addition, neoeriocitrin and 5,7‐dimethoxycoumarin were determined as two unique constituents of ‘Zhiqiao’ and ‘Foshou’, respectively. In conclusion, this study provides a chemical basis for quality control of Chinese medicinal materials from the Citrus genus.

Schizonepetae Spica (SS), the dried spike of Schizonepeta tenuifolia Briq., is a traditional Chinese medicinal herb. According to the color of persistent calyx, SS is categorized into two classes: the yellowish-green-type and the brownish-type. Based on the chemometrics analysis of gas chromatography-mass spectrometry (GC-MS), a novel model of identifying and evaluating the quality of SS in different colors was constructed for the first time in this work. 20 batches SS samples of different colors were collected and used to extract essential oils. The average essential oils yield of SS in yellowish-green color was significantly higher than that of SS in brownish color from the same origin (p<0.05). The GC-MS fingerprints of 20 batches SS samples whose correlation coefficients were over 0.964 demonstrated SS samples were consistent to some extent in spite of slightly different chemical indexes. A total of 39 common volatiles compounds were identified. Hierarchical clustering analysis (HCA), principal component analysis (PCA) and partial least-squares discriminate analysis (PLS-DA) were developed to distinguish SS samples characterized by different colors. Consistent results were obtained to show that SS samples could be successfully grouped according to their color. Finally, 4,5,6,7-tetrahydro-3,6-dimethyl-benzofuran and pulegone were detected as the key variables for discriminating SS samples of different colors and for quality control. The obtained results proved that SS of good quality were often yellowishgreen and those of poor quality were often brownish.

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