Biosynthesis of biolubricant catalyzed by lipase B from Candida antarctica immobilized on nanocomposite of cashew apple bagasse lignin

This research investigated the biosynthesis of a promising biolubricant, 2-ethylhexyl oleate (2EHO), catalyzed by Candida antarctica lipase B (CALB) immobilized on low-cost support derived from cashew apple bagasse (CAB) lignin. CAB lignin extraction was ensured through an acid-alkali process and used in the synthesis of a composite with magnetite (Lig-MNP), which was used as enzyme support. In the esterification reactions, the acid:alcohol molar ratios, temperatures, and catalytic loads were evaluated. The extraction yield of the CAB lignin was 73 %, and the synthesis yield of Lig-MNP was 56 %. The immobilization yields were greater than 90 %, and the biocatalyst with the highest activity was obtained using 5 mg of protein∙g−1 support, achieving an activity of 12.9 U/g. In the reactions catalyzed by this biocatalyst, the maximum conversion of 2EHO was 90 % using a catalytic load of 40 mg/mL, 1:5 M ratio at 40 °C and 36 h. The immobilized enzyme exhibited operational stability over cycles and was quickly separated between one cycle and another by magnetic action. Purified 2EHO attained above 90 % purities and presented properties necessary for use within a lubricant. These results underscore the potential of biocatalysts in sustainable biolubricant production, offering eco-friendly solutions by utilizing industrial waste.