Optimization of extraction of betalain from red beetroot (Beta vulgaris var. rubra (L.) Moq)

Abstract

Betalain is a pigment found in plants, can be red-violet (betacyanin) or yellow (betaxanthin), soluble in water, a compound widely used in chemistry, medicine and pharmacy with the chemical stability in a wide pH range. Betalain is an antioxidant with antiviral, anti-inflammatory properties. They are found in high levels in red beetroot and are a food coloring additive. The aim of this work was to study factors affecting the extraction of betalain from red beetroots such as solvent type, solvent concentration, material-solvent ratio, temperature and time. The results showed that 2.955 mg/g of dry matter was gained in the suitable extraction conditions such as ethanol 20%, material-to-solvent ratio 1/25 (w/v) at 40 °C for 180 minutes. Optimization of extraction of betalains from red beetroot using the response surface method (RSM) with three-factor central composite rotatable design (CCRD) showed the optimized parameters including material-to-solvent ratio 1:22.96 (w/v), the temperature at 47.71 °C, the period of 183.65 minutes gave the highest content of betalain (3.467 mg/g dry matter).