Olney C E, Jensen R G, Sampugna J, Quinn J G
Department of Animal Industries, University of Connecticut, 06268, Storrs, Connecticut.
Lipids. 1968 Nov;3(6):498-502. doi: 10.1007/BF02530893.
Acetone powders prepared fromVernonia anthelmintica seed catalyzed the release of 6.4 to 9.6 mu-moles of free fatty acids per milligram of protein when blended with olive oil and phosphate buffer and shaken for 20 min at 43 C. A 20 fold purification was achieved by differential centrifugation of an ammonium hydroxide extract of the acetone powder. Results from Sephadex G-200 chromatography and polyacrylamide gel electrophoresis suggested that the lipase activity was associated with a molecule of molecular weight greater than 200,000. Free fatty acids, 1,2- and 1,3-diglycerides, monoglycerides and glycerol were found in the digestion products. With most substrates the 1,2-to 1,3-diglyceride ratio was approximately 2ratio1 and monoglycerides tended to accumulate. Analysis of the digestion products from synthetic triglycerides of known structure indicated that both primary and secondary ester positions of the triglyceride molecule were hydrolyzed and that considerable isomerization of 1,2-diglyceride to 1,3-diglyceride occurred. The monoglyceride was consistently lower than the 1,2-diglyceride and in the majority of cases also lower than the 1,3-diglyceride in the fatty acid originally present in the 2 position of the triglyceride. No fatty acid preference was observed.
从驱虫斑鸠菊种子制备的丙酮粉与橄榄油和磷酸盐缓冲液混合，在43℃下振荡20分钟后，每毫克蛋白质催化释放6.4至9.6微摩尔游离脂肪酸。通过对丙酮粉氢氧化铵提取物进行差速离心实现了20倍的纯化。葡聚糖G - 200色谱和聚丙烯酰胺凝胶电泳结果表明，脂肪酶活性与分子量大于200,000的分子有关。在消化产物中发现了游离脂肪酸、1,2 - 和1,3 - 甘油二酯、甘油单酯和甘油。对于大多数底物，1,2 - 甘油二酯与1,3 - 甘油二酯的比例约为2:1，甘油单酯倾向于积累。对已知结构的合成甘油三酯消化产物的分析表明，甘油三酯分子的一级和二级酯位置均被水解，并且1,2 - 甘油二酯大量异构化为1,3 - 甘油二酯。甘油单酯始终低于1,2 - 甘油二酯，并且在大多数情况下也低于甘油三酯2位上原本存在的脂肪酸中的1,3 - 甘油二酯。未观察到脂肪酸偏好。
