Peroxidase inhibitory and antioxidant constituents from Juniperus L. species guided by HPTLC-bioautography and molecular docking studies

Abstract

The application of a newly developed HPTLC-bioautography assay for detecting peroxidase enzyme inhibitors in plant extracts in addition to bioautography methods for detecting antioxidant compounds resulted in the isolation of a new biflavonoid 3′-methoxy sahranflavone along with two known biflavonoids and three flavonoids from the leaves and cones of Juniperus communis, J. horizontalis and J. chinensis. The structures of all compounds were elucidated by means of 1 D and 2 D NMR and MALDI-TOF MS technique in addition to comparison to literature data. Quantitative estimation of antiperoxidase and antioxidative capacity based on DPPH free radical scavenging activity and β-carotene bleaching of extracts, active fraction and constituents was achieved by applying validated high resolution image analyses techniques. 3′-methoxy sahranflavone and quercetrin possessed high mutual antiperoxidase and antioxidant activities. Molecular docking simulations were performed to reveal the interaction of isolated compounds with human myeloperoxidase enzyme on the molecular level indicating the potential anti-inflammatory activity of 3′-methoxy sahranflavone and quercetrin.

Graphical Abstract

Keywords:

• . 3′-Methoxy sahranflavone
• HPTLC-bioautography
• antiperoxidase
• antioxidant
• Juniperus L.
• Molecular docking

Disclosure statement

No potential conflict of interest was reported by the authors.