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.

Abstract

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

Substances

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