Adulteration Identification of Angelica Sinensis Radix Based on Molecular Matrix Characteristics

Angelica sinensis radix (AS), the dried root of Angelica sinensis (Oliv.) Diels, is widely used in Chinese medicine and food products. However, after conducting market research, at least a quarter of AS on the market is commonly adulterated by Levisticum officinale W. D. J. Koch (LO), Angelica acutiloba (Sieb. et Zucc.) Kitagawa (AA), and Angelica gigas Nakai (AG), to varying degrees, which significantly affects its clinical efficacy and food safety. Therefore, there is a pressing need to establish safe and reliable methods for identifying illicit adulteration. In this study, the mass spectrometry (MS) information of AS, LO, AA, and AG was collected and converted into the data matrix for [t_R-m/z-I]. The top-n proprietary ions of AS, AG, AA, and LO were output as their molecular "matrix characteristics". Test samples were also analyzed, transformed into data matrices, and their own matrix characteristics were matched sequentially. For matching credibility (MC) results, a significant difference was found between the MC of the four herbs compared to their own matrix characteristics, as well as between the MC of the four herbs compared with their non-self matrix characteristics. Research results showed that based on matrix characteristics, AS and its adulterations can be identified with a matching credibility (MC) ≥ 78.0%; 3% adulterations can also be identified, and two market-blind samples were identified as exhibiting adulterations. In addition, chemometrics analysis demonstrated that adulteration identification based on matrix characteristics is reasonable and reliable. The matrix characteristics of AS and its adulterants contribute to adulteration analysis. The identification method, based on matrix characteristics, is safe and reliable which is conducive to AS's quality control and market supervision.