Extraction of lutein from targetes erecta using deep eutectic solvents

Abstract

In recent years, huge attention has been focused to replacing the conventional petrochemical solvents by green solvents i.e. deep eutectic solvents (DES). The main goal of this work is to eliminate the toxic and volatile solvents like hexane in the extraction process. Hexane is usually used for extraction, where the extract of final product may carry traces of organic solvent. DESs are eco-friendly solvents for the extraction of plant pigments when compared to petrochemical solvents like hexane. Deep eutectic solvents (DES) considered as an alternative green approach as it maintains ionic liquids merits on tunability, sustainable character and also overcomes the ionic liquids by its shortcomings. The 30-40% production of marigold flowers are wasted and dumped into waterbodies, which can be utilized in various ways and can get wealth out of it, by producing natural dye, Vitamin tablets, capsules from its petals which consists of flavonoid lutein and carotenoid-lutein. The present study focuses on extraction of plant metabolites (Lutein) through green methods, using Marigold is a source to extract Lutein. Different combination of DES used in the lutein extraction are choline chloride+ glucose (ChCl+glucose), choline chloride+glycerol (ChCl+glycerol), and choline chloride+ethanol (ChCl+ethanol) and were compared with commercial solvents (ethyl acetate and hexane). The combination of ChCl+glucose gives the highest yield of lutein oleoresin as 368.64 g/kg, which is higher than the conventional solvents. The analysis of lutein using HPLC have resulted in the highest area percent of lutein was 79.87%, at 474nm in the combination of ChCl+glucose. Results indicated that DES is a more viable and environment-friendly solvent for extraction of pigments from Targetus erecta.L. The present study focuses on extraction of plant metabolites (lutein) through deep eutectic solvents.