Chemical composition, antioxidant and antibacterial activities of Tamarix balansae J. Gay aerial parts

Abstract

A previously undescribed phenolic sulphate ester, potassium 34-dihydroxy-3-methoxybenzoic acid methyl ester-5-sulphate (1), along with nine known flavonoids, kaempferol-3-O-potassium sulphate-4′,7-dimethyl ether (2), kaempferol-4′,7-dimethyl ether (3), rhamnocitrin-3-O-potassium sulphate (4), rhamnocitrin (5), kaempferol (6), quercetin (7), afzelin (8), quercetin-3-O-α-l-rhamnopyranoside (9) and luteolin-3′-O-potassium sulphate (10) were isolated from the aerial parts of Tamarix balansae. Structures elucidation was performed by comprehensive 1D and 2D NMR analyses, mass spectrometry and by comparison with literature data. The antibacterial assay against Enterococcus faecalis, Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli and Pseudomonas aeruginosa bacteria showed a good activity for 2, 3, 7 and 9, with MICs ranging from 62.5 to 250 μg/mL. The abilities of these compounds to scavenge the DPPH were evaluated. Compounds 1, 7, 9 and 10 exhibited a good antiradical activity potential with IC₅₀ values ranging from 3.0 to 115.5 μg/mL, compared with ascorbic acid (IC₅₀ 7.4 μg/mL) which was used as positive control.

Keywords:

• Tamarix balansae
• Tamaricaceae
• flavonoids
• antibacterial activity
• antioxidant activity

Acknowledgements

The authors are grateful to CNRS, Conseil Régional Champagne Ardenne, Conseil Général de la Marne and to the PlANET CPER project, for financial support. Algeria and French government for the Profas grant to Mr. Abbes Benmerache were also gratefully acknowledged. We also acknowledge Janick Madoux (Laboratory of Bacteriology, CHU Reims) for accessing to multiple inoculators material, and Chantal Grimplet for technical support.