Triacylglycerol lipase from rape (Brassica napus L.) suitable for biotechnological purposes

Triacylglycerol lipase (EC 3.1.1.3) from rape (Brassica napus L. cv Ceres) is quite easily prepared from the 100,000 x g supernatant of cotyledon homogenates. The lipase is present in a high-molecular-mass fraction ( > 1.5 x 10⁶ dalton by gel filtration), but it can be rapidly extracted from the 100,000 xg supernatant by precipitation with polyethyleneglycol 8000 (4%, w/v) and MgCl₂ (40 mM) giving about a 10-fold purification. After delipidation, the lipase has an M_r of about 300,000. It hydrolyzes triacylglycerols to fatty acids and glycerol, although the fatty acids from the sn-1 or -3 positions are hydrolyzed first to yield 1,2(2,3)-diaclyglycerols. Lipase immobilized onto Celite by precipitation with acetone at-20°C catalyzes the esterification of oleic acid with butanol dissolved in hexane.