Directional anchoring of polymer-lysozyme nanohybrids for adhesive capture and enhanced removal of Alicyclobacillus acidoterrestris in fruit juices

The acidophilic and heat-resistant traits of Alicyclobacillus acidoterrestris (A. acidoterrestris) present a formidable challenge to fruit juices production safety. To address the limitations of conventional thermal sterilization, a novel bacterial capture device MPDEL has been developed. This innovative device utilizes dopamine-coated magnetic nanoparticles that are covalently linked with lysozyme, enabling efficient and rapid capture of A. acidoterrestris in acidic juices, followed by facile magnetic-controlled separation for subsequent removal. Lysozyme not only recognizes and directional anchors the bacterial surface, but facilitates the adhesion of polydopamine to the bacterial surface. Benefiting from the abundant binding sites and rapid adsorption kinetics, this un-thermal treatment completely removes 10⁴ CFU/mL of A. acidoterrestris from the juice within a span of 20 min. The MPDEL exhibits high capture performance, negligible cytotoxicity and no discernable impact on juice quality, offering a novel option for the removal of A. acidoterrestris from fruit juices.