Abstract: Salidroside is an important pharmacologically active compound in the traditional Chinese medicinal herb Rhodiola rosea L. In this work, five strains were isolated from soil around the roots of herb, and their catalytic activity for the synthesis of salidroside from D-glucose and tyrosol was tested. F1 strain, which was identified as Aspergillus oryzae, produces the highest amount of salidroside among the five strains. Therefore, its whole cells were used as catalyst for the synthesis of salidroside from D-glucose and tyrosol. The content of salidroside and tyrosol was analyzed by high-performance liquid chromatography. The results show that the highest yield of salidroside is 0.7 g/L under the optimal conditions, i.e., the tyrosol concentration of 5 g/L, reaction time of 48 h, cell concentration of 150 g/L, 30 ℃, and pH of 7. When the tyrosol concentration in the medium is above 5 g/L, the cell growth and the salidroside synthesis are both inhibited. Salidroside is only found inside the cells.

Key words: salidroside, microorganism, Aspergillus oryzae, biocatalysis, tyrosol, glucose, glucosylation