Emulsion Systems Stabilized with Nonionic Emulsifier and Cross-Linked Polyacrylic Acid: A Promising Strategy to Enhance the Activity of Immobilized CALB

The application of lipases in biphasic oil–water emulsions offers an efficient and sustainable alternative to conventional chemical synthesis. However, the natural immiscibility of these phases is a substantial limitation. To address this issue, we proposed a dual-stabilized emulsion system combining a nonionic emulsifier (Kolliphor® CS 20) and cross-linked polyacrylic acid (Carbopol® Ultrez 10), exceeding conventional single-stabilized systems. The activity of Candida antarctica lipase B (CALB), both in its free form and immobilized onto an IB-D152 support, was investigated in the prepared emulsion system. The olive oil emulsion stabilized with 10.0% Kolliphor® CS 20 and 0.1% Carbopol® Ultrez 10 significantly enhanced the lipolytic activity of immobilized CALB (156.27 ± 3.91 U/g of support), compared to the activity obtained in the emulsion stabilized only with 10.0% Kolliphor® CS 20 (71.11 ± 3.86 U/g of support). On the other hand, the activity of immobilized CALB in the emulsion containing 5.0% Kolliphor® CS 20 and 0.1% Carbopol® Ultrez 10 (62.22 ± 3.85 U/g of support) was lower than in the corresponding system without Carbopol® Ultrez 10 (72.03 ± 4.63 U/g of support), stabilized with only 5.0% Kolliphor® CS 20. Furthermore, immobilization onto IB-D152 led to lipase hyperactivation, with activity approximately eight-fold higher than that of free CALB. This dual emulsion stabilization strategy not only improves emulsion stability but also enhances lipase activity, offering new opportunities for scalable, high-performance biocatalysis using emulsions in industrial applications.