Immobilization Of The ?-galactosidase In The Inorganic Hybrid Nanoflower For The Lactose Hydrolysis

Lactose is the main source of calories obtained from milk during human infancy.However,some people lack lactase in their bodies and therefore cannot digest lactose.Lactose is fermented by microorganisms in the intestinal tract to cause some uncomfortable symptoms,leading to lactose intolerance and affecting human health.Currently,?-galactosidase hydrolysis is mainly used to remove or reduce lactose in milk or dairy products,which can effectively alleviate lactose intolerance.Enzyme immobilization technology can improve the stability and catalytic activity of the enzyme,and realize the reuse of the enzyme.Inorganic hybrid nanoflowers,a kind of flower-like nanomaterials formed by self-assembly of Cu²⁺and organic components,have been successfully applied in many fields in recent years.The synthesis conditions of the inorganic hybrid nanoflowers are mild,requiring less operation and easy to recycle,which are more suitable for industrial production.Therefore,in this paper,Cu₃(PO₄)₂was selected as the carrier,through the interaction of?-galactosidase(?-Gal)and Cu²⁺,the inorganic hybrid nanoflower complex?-Gal@Nanoflower with porous and petal-like structure was constructed.The composite was systematically characterized by means of thermal weight loss analysis,Fourier infrared spectroscopy,and laser confocal scanning,which confirmed that the immobilization strategy can effectively assemble?-Gal molecules in nanoflowers.We used 2-nitrophenyl-?-D-galactopyranoside as the substrate to determine the enzyme activity of?-Gal@Nanoflower.Compared with free enzymes,?-Gal@Nanoflower still has higher relative activity in extreme environments such as high temperature and alkaline.In addition,when metal ions are present,?-Gal@Nanoflower can effectively protect enzyme molecules from damage by metal ions and maintain stable catalytic activity.Not only that,the inorganic hybrid nanoflower has good storage stability and repetitive utilization rate,which is beneficial to the transportation and long-term storage of enzymes,and at the same time reduces production costs.In summary,by constructing?-Gal@Nanoflower complex,it can not only maintain?-Gal activity,but also improve its stability and prolong storage time;this method can effectively achieve lactose hydrolysis,which has the potential to solve lactose intolerance,and has a good prospect in the industrial application of biocatalysts.