Abstract:Naringinase can hydrolyze bitter substances, such as naringin in citrus fruits, which is applied in juice debittering or preparation of pharmaceutical intermediates, for example, prunin. In this study, calcium alginate/carboxymethyl chitosan/silica gel composite microspheres, which were environmental friendly and accessible with abundant resources, were prepared by dropping method and used as carriers for naringinase immobilization. The optimized specific enzyme activity, enzyme loading rate and enzyme activity recovery of immobilized naringinase could reach 203.33 U/g, 36.80% and 62.15%, respectively, under the following conditions: silica gel/carboxymethyl chitosan mass ratio of 1.0∶1.5, crosslinking time of 2.0 h, immobilization temperature of 25 ℃, coupling time of 4 h, and enzyme dosage of 465.6 U/mL. Meanwhile, compared with the free naringinase, this immobilized naringinase exhibited better stability to pH and thermal changes, and showed the feasibility of operation and storage. Besides, the application of naringinase immobilized on calcium alginate/silica gel/carboxymethyl chitosan composite microspheres would further expand the development of naringinase in food, medicine and other fields.