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Updated: Jun 11, 2026

Evaluating Leaf Responses to Microbial Secondary Metabolites Using A High-Throughput Format
Published on: December 5, 2025
Antioxidant effects of secondary metabolites from Geranium psilostemon
Didem Söhretoğlu1, Suna Atasayar Sabuncuoğlu, M Koray Sakar
1Department of Pharmacognosy, Faculty of Pharmacy, Hacettepe University, 06100 Ankara, Turkey. didems@hacettepe.edu.tr
Abstract:
An investigation was made of the effects on endogenous antioxidant enzyme activities and H2O2-induced lipid peroxidation inhibition in human red blood cells of the crude MeOH extract and its EtOAc, n-BuOH, and H2O sub-extracts obtained from aerial parts of Geranium psilostemon Ledeb., as well as compounds isolated from the most active EtOAc extract. Gallic acid (1), methyl gallate (2), pusilagin (3), 1,3,6-tri-O-galloyl-beta-glucopyranoside (4), 1,2,3,4,6-penta-O-galloyl-beta-glucopyranoside (5), kaempferol (6), quercetin (7), kaempferol 7-O-alpha-rhamnopyranoside (8), and quercetin 7-O-alpha-rhamnopyranoside (9) were isolated from the aerial parts of the title plant, and their structures identified from spectroscopic (UV, 1D- and 2D- NMR) and spectrometric (TOF-MS) data. All extracts and isolated compounds inhibited H2O2-induced lipid peroxidation and also enhanced the activity of superoxide dismutase (SOD) and catalase (CAT).
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