Antioxidant, UV-Protective, and Adsorption Properties of Lignins Extracted from Different Lignocellulosic Biomass Using a Deep Eutectic Solvent

Abstract — The extraction of lignin was carried out from corn cobs, pine and aspen sawdust using a deep eutectic solvent choline chloride/oxalic acid (molar ratio 1 : 1). The extracted lignins were characterized by UV-visible and Fourier transform infrared spectroscopy methods. Their antioxidant and UV-protective properties were compared. Lignins from the pine and aspen had a high antioxidant activity towards DPPH • and ABTS +• free radicals, while lignin from the corn cobs had the highest adsorption capacity towards the synthetic dye methylene blue (30.8 mg/g). All three lignins demonstrated a high efficiency as an active component of UV-shielding films and can be used in food packaging and cosmetics.