Abstract:Objective This study aimed to develop a catalytic system utilizing immobilized enzyme coupling glycosyltransferase for the synthesis of salidroside. Method The prokaryotically expressed glycosyltransferase UGT85AF8 and sucrose synthase GmSUS were immobilized on nickel-chelated polyacrylic acid resin. The immobilized UGT85AF8 was used to catalyze tyrosol glycosylation, and the immobilized GmSUS was used for the regeneration of uridine diphosphate glucose (UDPG). The reaction system conditions, including temperature, pH, enzyme loading, and substrate concentration, were optimized. The reusability of immobilized enzymes was investigated, and salidroside was separated and purified via the macroporous resin LSA-30. Result Under optimal conditions, the reaction for 12 h achieved a salidroside titer of 11.87 g/L. Moreover, the average molar conversion rate was 88.47% in six consecutive reaction batches. After purification, the purity of salidroside exceeded 99%, with a crystallization recovery rate of 51.49%. Conclusion The immobilized enzyme coupling catalytic system demonstrates promising potential for industrial-scale production of salidroside.
