Chemical study, antioxidant, anti-hypertensive, and cytotoxic/cytoprotective activities of Centaurea cyanus L. petals aqueous extract

Food Chem Toxicol. 2018 Aug;118:439-453. doi: 10.1016/j.fct.2018.05.046. Epub 2018 May 19.


This study aimed to optimise the experimental conditions of extraction of the phytochemical compounds and functional properties of Centaurea cyanus petals. The following parameters were determined: the chemical composition (LC-ESI-MS/MS), the effects of pH on the stability and antioxidant activity of anthocyanins, the inhibition of lipid peroxidation, antioxidant activity, anti-hemolytic activity, antimicrobial, anti-hypertensive, and cytotoxic/cytoprotective effect, and the measurements of intracellular reactive oxygen species. Results showed that the temperature and time influenced (p ≤ 0.05) the content of flavonoids, anthocyanins, and FRAP. Only the temperature influenced the total phenolic content, non-anthocyanin flavonoids, and antioxidant activity (DPPH). The statistical approach made it possible to obtain the optimised experimental extraction conditions to increase the level of bioactive compounds. Chlorogenic, caffeic, ferulic, and p-coumaric acids, isoquercitrin, and coumarin were identified as the major compounds in the optimised extract. The optimised extract presented anti-hemolytic and anti-hypertensive activity in vitro, in addition to showing stability and reversibility of anthocyanins and antioxidant activity with pH variation. The C. cyanus petals aqueous extract exhibited high IC50 and GI50 (>900 μg/mL) values for all cell lines, meaning low cytotoxicity. Based on the stress oxidative assay, the extract exhibited pro-oxidant action (10-100 μg/mL) but did not cause damage or cell death.

Keywords: Desirability function; Flavonoids; LC-ESI-MS/MS; Phenolic compounds; Protocyanins; Response surface methodology.

MeSH terms

  • Anthocyanins / analysis
  • Antihypertensive Agents / pharmacology*
  • Antineoplastic Agents, Phytogenic / pharmacology*
  • Antioxidants / pharmacology*
  • Caffeic Acids / analysis
  • Cell Line, Tumor
  • Centaurea / chemistry*
  • Chlorogenic Acid / analysis
  • Chromatography, Liquid
  • Coumaric Acids / analysis
  • Coumarins / analysis
  • Drug Evaluation, Preclinical
  • Flowers / chemistry*
  • Hemolysis / drug effects
  • Humans
  • Hydrogen-Ion Concentration
  • Inhibitory Concentration 50
  • Lipid Peroxidation / drug effects
  • Microbial Sensitivity Tests
  • Plant Extracts / chemistry*
  • Plant Extracts / pharmacology*
  • Quercetin / analogs & derivatives
  • Quercetin / analysis
  • Spectrometry, Mass, Electrospray Ionization
  • Tandem Mass Spectrometry
  • Water / chemistry


  • Anthocyanins
  • Antihypertensive Agents
  • Antineoplastic Agents, Phytogenic
  • Antioxidants
  • Caffeic Acids
  • Coumaric Acids
  • Coumarins
  • Plant Extracts
  • Water
  • isoquercitrin
  • Chlorogenic Acid
  • Quercetin
  • coumarin
  • ferulic acid
  • caffeic acid