Abstract: Eight kinds of macroporous resins were comparatively used to immobilize phospholipase A1, and the best carrier was found to be D001. The optimum conditions for immobilization were as follows: pH 5.0, phospholipase dosage 1.5 mL/g and 4 h reaction, yielding an activity of immobilized enzyme as high as 665.8 U/g. The degumming of rapeseed oil with the immobilized enzyme was optimized using response surface methodology. The optimum conditions were determined as follows: immobilized enzyme dosage 1.8 g/kg, pH 5.5, reaction time 3.6 h, and reaction temperature 51 ℃. The phosphorus content of degummed oil prepared under these condition was 5.82 mg/kg. After fifth repeated use, the immobilized enzyme still retained 47.9% of its initial activity and the phosphorus content of degummed oil was 9.78 mg/kg.

Key words: phospholipase A1, immobilization, macroporous resin, degumming