A new antioxidant compound from Capparis spinosa

Abstract

An activity-directed fractionation and purification process was used to isolate 1,1-diphenyl-2-picrylhydrazyl radical (DPPH•) scavenging components from fruits of Capparis spinosa L. (Capparaeae). Ethyl acetate and aqueous fractions showed greater DPPH• scavenging activities compared to the petroleum ether fractions. The ethyl acetate fraction was subjected to purification using column chromatography. A new antioxidant cappariside (4-hydroxy-5-methylfuran-3-carboxylic acid, 1), together with seven known organic acids (2–8) for the first time from plants of genus Capparis and four known organic acids (9–12) were isolated from C. spinosa. The structures were elucidated by extensive analysis of 1D- and 2D-NMR spectroscopic. In addition, compounds 1, 2, 4, 5, 9, 10 and 12 indicated strong scavenging capacity for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals with a SC₅₀ value of 0.204 ± 0.002, 0.007 ± 0.0, 0.011 ± 0.0, 0.044 ± 0.0016, 0.032 ± 0.0, 0.090 ± 0.001, and 0.350 ± 0.017 mM, respectively.

Keywords::

• Capparis spinosa
• cappariside
• antioxidant
• organic acids

Acknowledgement

This work was supported by a research grant from foundation of Shanghai Municipal Education Commission (No. 05CZ31 awarded to Professor Chang-hong Wang).

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.