Extraction and identification of anthocyanins

The use of organic solvents such as methanol and ethanol to extract anthocyanin pigments causes a toxicity issue.

 Although ethanol is considered as a generally safe extraction medium, isolation of anthocyanins using water-based extraction is consider a greener way.

  This extraction technique uses acidified water (0.01% HCl, pH ~2.3) that is subjected to high temperatures between 110–160°C under a constant pressure of 40 bars

  This increases the solubility of anthocyanins from the plant during extraction with water.

Anthocyanins are extracted from plants as a crude mixture. For that reason, separation or isolation of specific type of anthocyanin is needed for a specific purpose. 

 These include thin layer chromatography, high speed countercurrent chromatography, high-performance liquid chromatography, cellulose column chromatography, and reversed-phase ion-pair chromatography, as well as gas chromatography.

 In addition to separation and identification of anthocyanins, quantification of these compounds is commonly done by various chromatographic methods. High-performance liquid chromatography is the most used method in quantification of anthocyanins.