STUDY OF EXTRACTION AND EVALUATION OF EFFECT OF pH ON STABILITY AND COLOR OF BETACYANINS EXTRACTED FROM PURPLE HEART (Tradescantia pallida) LEAVES

Abstract

This study aimed to determine the conditions suitable in the process of extracting betacyanins and investigating the effect of pH on the color fastness of betacyanins extracted from the purple heart (Tradescantia pallida) leaf. Survey factors included solvents (water, ethanol, and methanol), extraction conditions, and material/solvent ratio (w/v). The total content of betacyanins (determined by UV-Vis spectroscopy method) was used as a control parameter for the experimental process. The results showed that the highest content of betacyanins in the extract when extracted with 50% methanol and the ratio of material/solvent (w/v) was 1: 5, under the ultrasonic condition of 15 minutes at 60 °C, the capacity of 200W. The extract obtained with the highest total amount of betacyanins in the extract was 7,209 ± 0,061 mg/L. Besides, the effect of pH on the durability, color, and maximum absorption of betacyanins extracted from the Tradescantia pallida leaves was also investigated. The survey results showed that betacyanins extracted from the Tradescantia pallida leaf had the color and maximum absorption change with pH, ​​unstable in an alkaline solution.

Keywords: Purple heart (Tradescantia pallida), betacyanins, UV-Visible, ethanol, methanol