Biological activities and phytochemical composition of organs from Loranthus europaeus

Abstract

Yellow mistletoe (Loranthus europaeus Jacq.) is one of the Turkish hemi-parasitic plants that mostly grows on oak trees and produces its own carbohydrates. The goal of this study was to analyze the antioxidant and enzyme inhibition activities, and the phenolic profiles of methanol extracts of three L. europaeus organs (fruits, stalks and leaves). Results showed that total polyphenols and flavonoids, and the individual phenolic compounds were significantly different among the three organs (p ? 0.05). The screening of individual phenolic compounds in the methanolic extract revealed 22 identified compounds. Five compounds (+)-catechin, (?)-epicatechin, chlorogenic acid, hyperoside and pinoresinol were predominant. Furthermore, important antioxidant activities in all organ extracts were assessed with five different methods. The highest antioxidant capacity was detected in stalks extracts using FRAP (0.30 ± 0.01 mg/mL), CUPRAC (0.08 ± 0.01 mg/mL), ABTS (0.51 ± 0.01 mg/mL), DPPH (0.53 ± 0.01 mg/mL) and phosphomolybdenum (1.60 ± 0.13 mg/mL) assays. However, the methanolic extract from fruits showed the highest activity for ferrous ion chelating activity (6.77 ± 0.25 mg/mL). Besides, the all organs extracts were active against tyrosinase and ?-amylase. However, the inhibition against both enzymes was higher in stalks extracts compared with fruits and leaf extracts. Pearson correlation confirmed that the strong biological activity of methanol extract from L. europaeus stalks was mainly due to its high content of (+)-catechin. © 2019 Elsevier B.V.