LC–MS/MS Profiling of Algerian Zizyphus lotus Extracts and their in vitro Antioxidant Activity: A Comparative Study

In this study, it was aimed to determine antioxidant activities and chemical composition of leaf and fruit extracts of Zizyphus lotus which has been used traditionally in folk medicine of Algeria. Total phenolic content (TPC) and total flavonoid content (TFC) were determined by the colorimetric assay, respectively. The extracts were analyzed by LC–MS/MS. Furthermore, the antioxidant potential of various extracts was evaluated using different antioxidant assays such as 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, ferric reducing antioxidant power (FRAP) assay, 2,2-azinobis-ethylbenzothiozoline-6-sulphonic acid (ABTS), and Phenanthroline activity using UV spectrophotometer. The quantitative analysis of polyphenols and flavonoids content showed that the leaves have the highest amount (279.07±18.84 mg GAE/g E and 132.74±27.74 mg ER/g E, respectively). The highest antioxidant activity was observed in the leaves with the value of 24.10±3.49 µg/mL, 9.365 ± 0.532 µg/mL, 0.19±0.093, 0.636±0.033 mg AAE/g, and 12.11±0.81 µg/mL for DPPH, ABTS, total antioxidant capacity, FRAP and Phenanthroline activity, respectively. The LC–MS/MS analysis of leaves reveals the presence the major compound, rutin (24392.59 mg/g), when fruits contain hesperidin (311.70 mg/g) as a major compound.