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Updated: Feb 6, 2026

Defining Substrate Specificities for Lipase and Phospholipase Candidates
Published on: November 23, 2016
A Continuous and Sensitive Spectrophotometric Assay for Lipase and Phospholipase A Activities Using α-Eleostearic
Meddy El Alaoui1, Laurent Soulère2, Alexandre Noiriel1
1Univ Lyon, Université Lyon 1, Institut de Chimie et de Biochimie Moléculaires et Supramoléculaires, UMR 5246 CNRS, Métabolisme, Enzymes et Mécanismes Moléculaires (MEM²), Villeurbanne Cedex, 69622, France.
Abstract:
To date, several sensitive methods, based on radiolabeled elements or sterically hindered fluorochrome groups, are usually employed to screen lipase and phospholipase A (PLA) activities. Here, a new ultraviolet spectrophotometric assay for lipase or PLA was developed using natural triglycerides or synthetic glycerophosphatidylcholines containing α-eleostearic acid (9Z, 11E, 13E-octadecatrienoic acid) purified from Aleurites fordii seed oil. The conjugated triene present in α-eleostearic acid constitutes an intrinsic chromophore and consequently confers strong UV absorption properties of this free fatty acid as well as of lipid substrates harboring it. The substrate was coated into the wells of a microplate, and the lipolytic activities were measured by the absorbance increase at 272 nm due to the transition of α-eleostearic acid moiety from the adsorbed to the soluble state. This continuous assay is compatible with a high-throughput screening method and can be applied specifically to the screening of new potential lipase, PLA1 and PLA2 inhibitors.
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