Abstract: Objective: This study aimed to comprehensively analyze metabolites in Lycium fruits and identify differential metabolites among different Lycium species for the purpose of providing a reference for in-depth exploitation and utilization of Lycium fruits of different species. Methods: Metabolites in the dried fruits of Lycium ruthenicum Murr and Lycium barbarum L. var. auranticarpum K. F. Ching were identified and compared by widely targeted metabolomic analysis based on ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Results: A total of 1 098 metabolites were detected belonging to 12 classes including amino acids and their derivatives, phenolic acids, flavonoids, alkaloids and lipids, among which phenolic acids, flavonoids and alkaloids accounted for the highest proportions. Through principal component analysis (PCA) and cluster analysis, it was found that 235 differential metabolites were up-regulated and 252 differential metabolites were down-regulated in L. ruthenicum Murr compared with L. barbarum L. var. auranticarpum K. F. Ching. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that the differential metabolites between the two Lycium species were mainly involved in the biosynthesis of flavonoids, tropane, piperidine and pyridine alkaloids, secondary metabolites, and ABC transport. Conclusion: Lycium fruits of different species have significant differences in the contents of metabolites. This study provides some theoretical guidance for the development and utilization of Lycium ruthenicum Murr and Lycium barbarum L. var. auranticarpum K. F. Ching.

Key words: Lycium ruthenicum Murr; Lycium barbarum L. var. auranticarpum K. F. Ching; metabolomics; metabolites; flavonoids; alkaloids