关键词: 酶催化, 纳米凝胶, 稳定性, 非水相, 红景天苷

Abstract: To efficiently prepare salidroside, the encapsulation of β-glucosidase into nanogel was accomplished via the two-step in situ polymerization and used as the catalyst to synthesize salidroside with glucose and tyrosol as substrates in a non-aqueous system by reverse hydrolysis. The tolerance of the enzyme nanogel and the effects of different organic solvents, water content, enzyme dosage, pH, temperature and the substrate concentration on the synthesis of salidroside were investigated. Because the enzyme nanogel could effectively enhance the thermo-stability and the tolerance of organic solvents, β-glucosidase nanogel was well suitable for the synthesis of salidroside by reverse hydrolysis. The results showed that t-butanol was the best organic solvent whenthe water content of system was 5%, the enzyme dosage was 4.0U/mL, the pH was 6.0, the reaction temperature was 60℃, and the concentrations of glucose and tyrosol were 300mmol/L and 900mmol/L, respectively. Under the optimized conditions, the concentration of salidroside was 71.13mmol/L, and the yield could reach up to 23.7% after reaction for 96h. The research provided a new and more effective approach for enzymatic synthesis.

Key words: enzymatic catalysis, nanogel, stability, non-aqueous media, salidroside