▎ 摘　　要

NOVELTY - A modified silk protein-based polyphenol oxidase nano efficient absorption fixing film comprises 23-27 pts. wt. silk protein, 10-11 pts. wt. edible nano graphene, 2-5 pts. wt. 90% sodium hydroxide, 0.8-1 pt. wt. potassium sulfate, 8-10 pts. wt. diatomaceous earth, 6-8 pts. wt. chitosan, 3-4 pts. wt. sodium alginate, 3-5 pts. wt. glutaraldehyde, 16-20 pts. wt oyster shell, and preset amount of deionized water, ethanol, and dilute acetic acid ionic liquid. USE - Modified silk protein-based polyphenol oxidase nano efficient absorption fixing film (claimed). ADVANTAGE - The modified silk protein-based polyphenol oxidase nano efficient absorption fixing film has excellent absorption efficiency and decomposition resistance due to the presence of oyster shell powder, diatomaceous earth, edible nano graphene and modified silk protein, and is prepared by simple method. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of modified silk protein-based polyphenol oxidase nano efficient absorption fixing film, which involves pretreating oyster shell by heating oyster shell with diluted sodium hydroxide solution at 50 degrees C for 50-60 minutes, taking out, rinsing with deionized water to neutral, calcining at 600 degrees C for 2-3 hours, obtaining oyster shell powder, mixing oyster shell powder, diatomaceous earth and edible nano graphene, adding ethanol, stirring, heating to 200 degrees C for 10-12 hours, cooling, activating, obtaining adsorbent, mixing activated adsorbent and silk protein, homogenizing using high-pressure homogenizer at 40 degrees C for 3-4 hours, obtaining modified silk proteins, mixing chitosan, sodium alginate and dilute acetic acid ionic liquid, homogeneously stirring 30-60 minutes, obtaining dissolving liquid, magnetically stirring dissolving liquid, modified silk protein, potassium sulfate, polyphenol oxidase, glutaraldehyde and deionized water using ultrasonic power of 50 W for 20-22 hours, obtaining enzyme immobilization colloid, adding the resultant product to flat groove polyethylene mold at 60 degrees C and preparing film having size of 1-1.6 mm.