Enzymatic synthesis and characterization of 1‐lipoyl‐2‐palmitoyl phosphatidylcholine: A novel phospholipid containing lipoic acid

Abstract

Bioorganic synthesis of a novel phospholipid, 1‐lipoyl‐2‐palmitoyl phosphatidylcholine (LPPC) was carried out using dipalmitoylphosphotidylcholine (DPPC) and lipoic acid as substrates via lipase catalyzed transesterification reaction at controlled water activity. A high lipoic acid concentration and low water activity were necessary for the enzymatic acidolysis reaction in an organic solvent medium at ambient temperature. Four immobilized lipases were examined for the incorporation of lipoic acid into DPPC. The transesterification reaction resulted in formation of the desired product along with the lyso PC as a by‐product at controlled water activity of 0.11 in 96 h using Lipozyme RM IM lipase. The composition of the modified PC showed that 41.07 mol% of lipoic acid was incorporated into DPPC. The transesterification was regioselective with nearly 91% incorporation of lipoic acid in the sn‐1 position with about 4% incorporation in the sn‐2 position in the product PC. The prepared LPPC can have applications as a lipid based prodrug of lipoic acid and also can have potential applications in drug solubilization and release studies.Practical applications: Novel phospholipid bearing lipoic acid as an active ingredient is synthesized via enzymatic route. It is a smart combination of two biologically active molecules with proven activities. The prepared phospholipid can have potential applications in nutraceuticals, cosmetics, and biomedical fields. This molecule can help to address the bioavailability issues of lipoic acid. The product can have applications in controlled release of lipoic acid due to incorporation into a phospholipid.Lipase‐catalyzed synthesis of 1‐lipoyl‐2‐palmitoyl phosphatidylcholine.