Preliminary spectroscopic and thermo-optical characterization of anthocyanin unpurified crude extracted from Tradescantia Pallida Purpurea

Abstract Anthocyanins are the most important natural dye structure, which are contained in the orange-red-blue colors of several plants, fruits, vegetables and roots. Anthocyanins derived from ornamental plants have shown a higher degree of acylation that corresponds to a greater chemical stability. This work presents the absorption and fluorescence spectroscopic characterizations of a natural dye in the unpurified crude extracts from leaves of Tradescantia pallida purpurea. Anthocyanin dye extraction from the leaves was performed using different solvents (water, alcohol and acetone) and concentrations without further purification. The thermo-optical parameters, such as the thermal diffusivity ( D ), fractional thermal load ( φ ) and quantum yield ( η ), were determined. The η results in aqueous solutions were compared to those obtained for other dyes.