▎ 摘　　要

NOVELTY - Magnetic graphene oxide multilayer nano- composite material immobilized tannase, comprises genipin to activate function and tannase bonding on the carrier. The function carrier is ferric oxide nano-particle modified graphene oxide and modified with multi-layer nano composite material. USE - Magnetic graphene oxide multilayer nano- composite material immobilized tannase. ADVANTAGE - The magnetic graphene oxide multilayer nano- composite material immobilized tannase obtains good stability and repeatable usability which can be applied to degradation of torreya extract tannin, obtaining the flexible arm and multiple anchoring sites of the multi-layer polymer genipin activation, and natural biological cross-linking covalently function and unique magnetic separation characteristic, the prepared nano-biological composite material has stable enzyme activity. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for the method for preparing magnetic graphene oxide multilayer nano-composite material immobilized tannase, which involves: 1. synthesizing magnetic graphene oxide multi-layer polymer nano composite material mGP3H2, the mass ratio of 1:150-200, adding GO with a mass of 30-45% of FeCl3asterisk6H2O, Na3Cit with a mass of FeCl3asterisk6H2O of 30-45%, and FeCl3asterisk6H2O with a mass of 4-40%, 7 times of NaAc and 2-4 times of FeCl3asterisk6H2O mass of PEG 2000, blending and dispersing to obtain the blend, stirring the blend, ultrasonically processing to obtain suspension, the suspension sealing heat treatment, collecting product mGO by ethanol and water for cleaning drying for future use; 2. dispersing the 100 mg mGO in 100 mL polyethylene imine and impacting for 16-25 min, the obtained product is named as mGP1 for magnetic separation, water washing the mGP1 re-dispersed in the sodium hyaluronate solution (0.2 mg mL-1, pH5.0), vibration the product is named as mGP1H1 magnetic separation water washing, after repeatedly processing for 4-6 cycles, the collected product is named as mGP3H2 and it is re-dispersed in containing N- hydroxysuccinimide (1 mg mL-1) and 1 - 3- dimethylaminopropyl - 3-ethyl-carbodiimide hydrochloride (1 mg mL-1) of PBS solution (10 mmol L-1, pH5.5), room temperature inducing cross-linking water washing to obtain the product; 3. preparing tannase immobilized nano biological catalyst mGP3H2 tannase preparation of the mGP3H2 dispersed in 4 mL phosphate buffer solution, containing 1.5mg mL-1 genipin, the mixture shaking for 5- 7h at 30degrees Celsius, washing by phosphate buffer solution and adding it into 20 mL phosphate buffer solution containing tannase; 4. culturing the mixed suspension for 6-8 hours at 30degrees Celsius, after magnetic separation washing with phosphate buffer solution to obtain the mGP3H2 tannase.