Cellulose nanofibril-stabilized Pickering emulsion as a high-performance interfacial biocatalysis system for the synthesis of phosphatidylserine.

[Display omitted] • A simple ball-milling method with the aid of ionic liquid was successfully applied to product cellulose nanofibrils. • A one-step immobilizing procedure was developed to produce the immobilized-on-cellulose enzyme. • The CNF-CBD1 was used as Pickering emulsions stabilizers for efficient synthesis of phosphatidylserine. • The Pickering emulsion obtained was an attractive Pickering interfacial biocatalysis platform. An efficient and attractive platform for synthesizing phosphatidylserine is indispensable for driving large-scale industrial applications. Given the interfacial effect of phospholipase D (PLD), an adequate oil-water interface surface is essential for the catalytic efficiency of PLD. Herein, a simple ball-milling method with ionic liquid was successfully applied to produce cellulose nanofibrils and immobilized PLD with the cellulose-binding domain through a one-step procedure. Each droplet in the Pickering reaction system was regarded as a microreactor to provide sufficient oil-water interface to the active sites of PLD. The constructed Pickering emulsion system exhibited outstanding catalytic activity, achieving 95.4 % conversion after 2 h with the minimal amount of catalyst (0.8 wt% of CNF-CBD1 addition amount), which was 6-fold higher than the previously reported immobilized MCC-CBD1 and 21-fold higher than free PLD-CBD1. These results demonstrated a sustainable and high-performance biocatalysis method, paving the way for the efficient synthesis of novel phospholipids. [ABSTRACT FROM AUTHOR]