Enzymatic Degumming of Arachidonic Acid Oil Using Immobilized Phospholipase A1 on Hollow Double-Layer Mesoporous Silica Nanoparticles

This study explores the application of immobilized phospholipase A1 (PLA1) on hollow double-layer mesoporous silica nanoparticles (PLA1@NH2/C8-HdlMS) for the degumming of crude arachidonic acid (ARA) oil for the first time. The immobilized enzyme was comprehensively characterized, and the reaction conditions were optimized via single-factor experiments. Under the optimized conditions (enzyme dosage 0.3%w/w, 35 °C, water addition 3%, and reaction time 90 min), PLA1@NH2/C8-HdlMS achieved a remarkable phosphorus removal rate of 97.9%, reducing the phosphorus content from 441.21 mg/kg to 9.29 mg/kg in 90 min (well below the food-grade standard of <10 mg/kg). The fatty acid composition of the oil remained almost unchanged, while the oxidative induction time of the degummed oil significantly improved by 42%. Notably, PLA1@NH2/C8-HdlMS demonstrated broad applicability across crude oils, with initial phosphorus contents ranging from 294.98 mg/kg to 537.44 mg/kg, and it maintained ~93% of its initial activity after 11 reuse cycles. Compared to traditional hydration degumming (with a phosphorus removal rate of 56.3%), this enzymatic method offers superior efficiency at lower temperatures, minimizing energy consumption and the thermal degradation of ARA. This green, efficient, and sustainable method for degumming heat-sensitive oils offers significant potential for the industrial application of high-quality functional oils by preserving PUFA integrity and reducing environmental impact.