Enzymatic Production of Phosphatidylserine Using a Phospholipase D Immobilized via a Composite Polysaccharide Strategy

Phosphatidylserine (PS), a valuable phospholipid, is widely used in food, pharmaceutical and cosmetic industries. Its enzymatic synthesis, catalyzed by phospholipase D (PLD) via transphosphatidylation under mild conditions, has drawn considerable attention. However, the industrial use of free PLD is limited by poor stability, difficult recovery, and high cost. To address these challenges, a ternary composite carrier—integrating the flexibility of chitosan, the stability of cellulose, and the macroporosity of agarose—was constructed for immobilizing the PLD from Streptomyces antibioticus (saPLD). The resulting saPLD@chitosan–cellulose–agarose biocatalyst demonstrated enhanced immobilization efficiency, catalytic performance, and stability across varying pH and temperatures. After eight consecutive batches of usage, the PS yield of saPLD@chitosan–cellulose–agarose reached over 60% of that from the first batch. Thus, this study established a new method for preparing immobilized saPLD, and developed a robust and promising platform for the efficient and sustainable production of PS.