Anti-inflammatory and antitumor phenylpropanoid sucrosides from the seeds of Raphanus sativus

Abstract

A bioassay-guided fractionation and chemical investigation of the MeOH extract of Raphanus sativus seeds resulted in the isolation and identification of eight phenylpropanoid sucrosides (1 – 8) including two new compounds, named raphasativuside A and B (1 – 2) from the most active CHCl3-soluble fraction. The structures of these new compounds were elucidated through spectral analysis, including extensive 2D-NMR data, and chemical reaction experiments. We evaluated the anti-inflammatory effects of 1 – 8 in lipopolysaccharide (LPS)-stimulated murine microglia BV2 cells. Compounds 2 and 5 exhibited significant inhibitory effect on nitric oxide production in LPS-activated BV-2 cells with IC50 values of 21.63 and 26.96µM, respectively. All isolates were also evaluated for their antiproliferative activities against four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT-15). Compounds 1 – 7 showed consistent cytotoxicity against A549, SK-OV-3, SK-MEL-2, and HCT-15 cell lines with IC50 values of 6.71-27.92µM. Additionally, the free-radical scavenging activity of 1 – 8 was assessed using the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay where compounds 1, 3, and 4 scavenged DPPH radical strongly with IC50 values of 23.05, 27.10, and 29.63 µg/mL, respectively.