Decolorization property of living Lichen Evernia prunastri on textile Acid Red P-2BX dye

Abstract

The removal of textile dye using the biosorption technique is important for improving water quality and avoiding the harmful effects of the traditional approach for removing wastewater on human health. Lichens are symbiotic organisms that have great potential for decolorization and degradation of textile dye. The present study evaluates Acid Red P-2BX dye decolorization by living lichen Evernia prunastri at the pH range of 2–10. Dye decolorization rates at pH 2 were 84.62%, 87.5% and 88.54% at 25, 50 and 100 mg/L of initial dye concentrations, respectively. The pigment analysis and mean intensity of chlorophyll autofluorescence results indicated that pH could be the main factor affecting lichen physiology and thalli decolorization capacity. Fourier transform infrared spectroscopy was used as a high-throughput method for understanding biomolecular changes in thalli. The lipid/amide I and carbohydrate/amide I ratio increased at pH 2. The present study also indicated, for the first time, that decolorization rate is related to altering lichen carbohydrate and especially lipid metabolism in the E. prunastri thalli. Thus, we demonstrated that the lichen E. prunastri could be a good candidate for use as a biosorbent.