UPLC-MS/MS-based metabolomics decipher anti-inflammatory metabolites from Ziziphus jujuba Mill. and Ziziphus spina-christi L. collected from diverse geographic localities; an in vitro multivariate statistical approach

Ziziphus is a cosmopolitan genus that has several traditional applications. One of them is alleviation of inflammation. However, Ziziphus mechanisms and exact biomarkers in charge of this effect are not extensively studied. Therefore, the aim of this study is to explore the phytochemical variability between the leaves’ extracts of two Ziziphus species gathered from diverse geographic localities, scrutinizing their in vitro anti-inflammatory effects, identifying the mechanisms and exact biomarkers accountable for these effects utilizing UPLC-MS/MS along with an in vitro multivariate statistical approach. Seventy-eight metabolites were annotated by UPLC-MS/MS. These metabolites were found to belong to different chemical classes such as alkaloids, terpenoids, and flavonoids. Multivariate statistical analysis revealed that samples’ segregation was relied on their species type rather than their origin. Then, testing the effects of the studied extracts on the gene expression of four pro-inflammatory cytokines (IL-1β, IL-6, TNF-α, and INF-γ) using polymerase chain reaction (PCR) showed that Z. jujuba extract originating from China downregulated TNF-α to levels less than those caused by piroxicam, indicating its higher efficacy. The Orthogonal Projection to Latent Structures (OPLS) coefficient plots indicated that zizybeoside I, zizyphine G and lotusine G were among the most potential metabolites downregulating the inflammatory cytokine TNF-α. However, ebelin lactone, oxyphylline B and zizyvoside I were from the more prominent biomarkers responsible for the downregulation of IL-1β. Furthermore, zizyphursolic acid, oxyphylline B and mauritine H, were strongly correlated with the downregulation of IFN-ɣ and IL-6. This study is the first attempt to decipher the anti-inflammatory metabolites from different Ziziphus species, valorizing their significance as a valuable traditional medicine.