Analysis of Secondary Metabolites of Elaeagnus Angustifolia Leaves Based on UPLC-Q-TOF-MS

Background: The leaves of Elaeagnus angustifolia, belonging to the Elaeagnaceae Juss. family, are known for their medicinal properties for relieving cough and asthma, as well as treating dysentery and diarrhea. Objective: To establish a rapid qualitative method for the detection of secondary metabolites in leaves of Elaeagnus angustifolia, including the identification and analysis of various secondary metabolites in leaves of Elaeagnus angustifolia. Method: Samples were separated using a Waters ACQUITY H-Class ultra-performance liquid chromatography (UPLC) system (FTN autosampler, quaternary LC pump) and ACQUITY UPLC (R) BEH C18 column (1.7 lm, 2.1 mm x 100 mm). The flow rate was set to 0.4 mL/min, the injection volume was 1.0 lL, and the column temperature was set to 45 degrees C. The mobile phase was methanol (A) with -0.1% formic acid in water (B). Samples were analyzed by quadrupole time-of-flight mass spectrometry (Q-TOF-MS). Results: A total of 182 different secondary metabolites were detected from 10 varieties of leaves of Elaeagnus angustifolia, including 77 flavonoids, 20 steroids, 7 alkaloids, 15 amino acids, 18 organic acids, and 45 other compound types. Conclusions: A method for the rapid analysis of leaves of Elaeagnus angustifolia by UPLC-Q-TOF-MS was established, and the secondary metabolites in leaves of Elaeagnus angustifolia were identified. The enrichment of secondary metabolites in leaves of different varieties of Elaeagnus angustifolia was clarified. Highlights: The UPLC-Q-TOF-MS method is very fast and possesses a high degree of selectivity, precision, and sensitivity. These findings provide a reliable foundation for the development of medicinal resources derived from Elaeagnus angustifolia leaves.