Abstract: The preparation of salidroside was successfully carried out in fourteen ionic liquids (ILs)-containing systems using β-glycosidase from black plum seeds for the first time. The optimum conditions were determined for C₆MIm?BF₄, pH, phosphate buffer content, and molar ratio of tyrosol to D-glucose to be 1% (v/v), 5.9, 20% (v/v), and 8:1, under which the initial reaction rate and yield were 3.3 mmol/(L·h) and 24.5%, respectively. Moreover, the effects of 1-alkylimidazolium-based ILs possessing different alkyl chain lengths from C₂ to C₁₀ and a variety of anions including BF₄^-, PF₆^-, Cl^-, Br^-, and I^- on enzyme activity in co-solvent systems were investigated. The results indicate that the optimal chain length of the alkyl substituent on the imidazolium ring of the cation was C₆.

Key words: ionic liquid, salidroside, glucosylation, black plum seed meal, co-solvent