Contemporary industrial development and swift urbanization require environmentally sustainable energy sources. Ethanol made from biomass provides unique environmental and economic strategic benefits and can be considered a safe and clean liquid fuel alternative to fossil fuels. Ethanolβs significant advantages, such as low cost, biodegradability, and abundance, make the application of biomass for production of biorenewable energy favorable. However, biomass must be subjected to pretreatment processes to liberate the components needed for effective enzymatic hydrolysis that converts cellulose to sugars prior to fermentation to create biofuel. Production of valueadded co-products besides biofuels, through coordinated bio refinery processes, requires selectivity during pretreatment. The current work concentrates on biomass pretreatment technologies with an emphasis on lignin dissolution using deep eutectic solvents (DES). DES are new βgreen\u27 solvents that have a high potential in biomass processing because of their low cost, low toxicity, biodegradability and easy recycling. The present work focuses on the preparation of three types of DES, pretreatment of abundantly available Loblolly pine needles, dissolution of lignin from the biomass and measurement of the mass yield of pine needles treated with different types of DES. The pretreated and raw biomass underwent FTIR analysis, fiber analysis and enzymatic hydrolysis to compare the pretreatment index of different DES on pine needles and also to investigate one of the applications of lignin as a natural dyeing component