To evaluate the chemical composition difference of Cassia angustifolia Vahl leaves and Cassia auriculata L. leaves by high-resolution mass spectrometry and omics analysis, so as to establish the detection method of Cassia auriculata L. leaves adulterated in Cassia angustifolia Vahl leaves.

The positive and negative MS^E data of 13 batches of Cassia angustifolia Vahl leaves and 9 batches of Cassia auriculata L. leaves were collected by ultra performance liquid chromatography coupled with electrospray ionization quadrupole time of flight mass spectrometry(UPLC-Q TOF MS). The mobile phase was acetonitrile(A)-1% acetic acid(B). The column temperature was 30 ℃. The flow rate was 0.3 mL·min^-1. Injection volume was 1 μL. The mass range was m/z 50-1 200. The chemical composition difference of Cassia angustifolia Vahl leaves and Cassia auriculata L. leaves were processed by the omics analysis QI software based on the orthogonal partial least-squares discrimination analysis(OPLS-DA) after the negative MS^E data were obtained. One out of seven specific components from Cassia auriculata L. leaves was separated and identified. A method with the specific component as the reference substance for the detection of adulterated Cassia auriculata L. leaves in Cassia angustifolia Vahl leaves was established by UPLC, and it was used in 27 batches of Cassia angustifolia Vahl leaves samples and 3 batches of laboratory-made positive samples.

Cassia angustifolia Vahl leaves and Cassia auriculata L. leaves were significantly different from each other. The specific component separated from Cassia auriculata L. leaves was identified as kaempferol 3-O-(2”-O-apiofuranosyl) rutinoside. In the method for the detection of adulterated Cassia auriculata L. leaves in Cassia angustifolia Vahl leaves by UPLC, the precision(RSD=1.3%), repeatability(RSD=1.3%) and stability(RSD=0.58%) met the requirements. No kaempferol 3-O-(2”-O-apiofuranosyl) rutinoside was detected in 23 out of 27 batches of Cassia angustifolia Vahl leaves samples, but it was detected in 4 batches of Cassia angustifolia Vahl leaves samples and 3 batches of positive samples made in the laboratory.

In this study, the difference of Cassia angustifolia Vahl leaves and Cassia auriculata L. leaves is distinguished clearly based on the technology of UPLC-Q TOF MS and OPLS-DA. The specific component of Cassia auriculata L. leaves is separated and identified. A method for the detection of adulterated Cassia auriculata L. leaves in Cassia angustifolia Vahl leaves is established by UPLC, and it provides the basis for quality control and quality standard improvement of Cassia angustifolia Vahl leaves. The technology is helpful to solve the problem of adulteration identification of traditional Chinese medicine.