Cross-linked enzyme aggregates of β-glucosidase from Prunus domestica seeds

Cross-linked enzyme aggregates (CLEAs) of β -glucosidase were prepared and characterized. Under the optimum conditions, the activity recovery of CLEAs reached 84 %. The reduction by NaBH 4 resulted in slightly lower activities of CLEAs, while their thermostability was enhanced. CLEAs were more thermally stable than free enzyme (half lives, 973 vs. 518 min at 50 °C), while less stable than seed meal (half life, 1,090 min). In 90 % (v/v) t -butanol, the half lives of CLEAs and free enzyme were 53 and 6.7 h, respectively. Besides, the catalytic efficiency ( V max / K m ) of CLEAs was comparable to free enzyme (0.42 vs. 0.47 min −1 mg −1 ). This carrier-free immobilized enzyme had a network structure with multiple layers. The productivity of salidroside using CLEAs reached 150 g/l g catalyst, while being 6.3 g/l g with seed meal.