Isolation and purification of lecithin by preparative high-performance liquid chromatography

Separation of phosphatidylcholine from soybean phospholipids by simulated moving bed

A simulated moving bed (SMB), equipped with eight silica-gel columns, was used to separate phosphatidylcholine (PC) from soybean phospholipids. The effects of flow rate in Sections 2 (Q(2)) and 3 (Q(3)), switching time, feed flow rate and feed concentration on the operating performance parameters: purity, recovery, productivity and desorbent consumption were studied. Operating conditions leading to more than 90% purity in both outlet streams have been identified, together with those achieving optimal performance. Regions leading to complete separation are observed and explained theoretically. As the mass-transfer effect was not considered, the triangle theory only gives initial guesses for the optimal operating conditions.

Phosphatidylcholine isolation from egg yolk phospholipids by high-performance liquid chromatography

Cell membrane components have been increasingly recognized as important biochemicals in the fields of biochemistry and pharmacy due to their relationship with metabolite transport in the cells. Among the components, phosphatidylcholine (PC) is considered a valuable biochemical, because it is difficult to commercialize. PC demand has been largely increased in the fields of the nutrient, cosmetic and pharmacy industries, and so the development of a preparative chromatography process is critical to supply a low-cost PC. In this study, we investigated the HPLC separation of phospholipid originated from egg yolk, which contains 80% (w/w) PC and 15% (w/w) phosphatidylethanolamine. Column temperature, mobile phase composition and its flow-rate and kinds of stationary phase were varied to understand the effectiveness of PC separation. For studying the relationship between recovery yield and sample loading amount in HPLC, we performed overloading experiments. In this way, we successfully separated PC with over 99% purity and with 98% yield with the following HPLC operating conditions; pure methanol as a mobile phase, 2.0 ml/min flow-rate and 1000 mg/ml feed concentration in a KR-100-10SIL column.

Chemical synthesis and surface activity of lung surfactant phospholipid analogs. III. Chiral N-substituted ether-amide phosphonolipids

A homologous series of chiral (R) ether-amide phosphonolipid analogs of naturally occurring (R) glycerophospholipids were synthesized and characterized for their interfacial behaviors. The phosphonolipids possess isoteric ether, amide, and phosphonate functions at positions corresponding to the sn-1, sn-2, and sn-3 ester functions, respectively, of naturally occurring glycerophospholipids. All compounds were synthesized with disaturated C16:0 alkyl/acyl moieties to give structural analogy with dipalmitoyl phosphatidylcholine (DPPC), the major glycerophospholipid component of lung surfactant. Further substitutions at the headgroup nitrogen were also used to generate differences in headgroup size and polarity in the synthetic compounds. The surface activity of the ether-amide phospholipids was investigated in terms of adsorption to the air-water interface, together with studies of dynamic respreading after monolayer collapse and surface tension lowering in dynamically compressed spread films and dispersions. Results showed that several ether-amide phosphonolipids had more rapid adsorption and improved dynamic respreading behavior compared to DPPC, plus the ability to lower surface tension into the range of less than 1 to 4 mN/m in spread films and in dispersions under dynamic conditions. In combination with a series of diether phosphonolipids synthetized in a companion study [1], these ether-amide compounds are useful in the development of molecular structure-surface activity correlates for lung surfactant-related materials, and should assist in investigating the specificity of interactions between phospholipids and other pulmonary biological molecules.