Long-chain triacylglycerol emulsion

Deckelbaum, R. J., Hamilton, J. A., Moser, A., Bengtsson-Olivecrona, G., Butbul, E., Carpentier, Y. A., Gutman, A., and Olivecrona, T. (1990), Medium-chain versus long-chain triacylglycerol emulsion hydrolysis by lipoprotein hpase and hepatic lipase Implications for the mechanisms of lipase action, Biochemistry, 29,1136-1142. 

Gargouri, Y., Pieroni, G., Riviere, C., Sau-NiERE, J.-F., Lowe, P.A., Sarda, L. and Verger, R. (1986b) Kinetic assay ofhuman gastric lipase on short- and long-chain triacylglycerol emulsions. Gastroenterology 91, 919-925. 

All of the described procedures use emulsified substrate. Although the p-nitrophenyl laurate assay cocktail is stable for 3 days at 4°C, the emulsified olive oil substrates (or other triacylglycerol-based substrate systems) should be made fresh daily and rehomogenized periodically and when separation is visually evident. Use of day-old emulsion substrate will yield increased blank values for titratable acidity, and this effectively compromises the limit of detection of activity. Emulsified substrates should be in liquid form at common assay conditions (20° to 50°C), and partially solidified substrates (those rich in long-chain saturated fatty acids) will cause interfacial irregularities and confound the assessment of lipases in ways that cannot be accounted for. 

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