MODIFICATION OF PHOSPHOLIPIDS WITH LIPASES AND PHOSPHOLIPASES

Different commercial lipases and phospholipases were studied iii the h ydrolysis and transesterification of synthetic phosphatidylcholine and soybean lecithin. Wide variations in the lipase and phospholipase act ivities and in the protein contents of the preparations were observed. The substrate specificity varied between different enzymes. A high de gree of hydrolysis of synthetic and soybean phospholipids was achieved with both types of enzymes. Enzymes immobilized on Celite were used i n the transesterification of dimyristoyl phosphatidylcholine and oleic acid. The conversions were carried out both without solvent and in th e presence of toluene. The amount of modified phosphatidylcholine was measured using HPLC. The highest amount of modified phosphatidylcholin e was obtained in solvent-free transesterification. The best results w ere obtained with Aspergillus niger lipase.