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Phosphatidylcholine
Phosphatidylcholines (PC) are a class of phospholipids that incorporate choline as a headgroup. They are a major component of biological membranes and can be easily obtained from a variety of readily available sources, such as egg yolk or soybeans, from which they are mechanically or chemically extracted using hexane. They are also a member of the lecithin group of yellow-brownish fatty substances occurring in animal and plant tissues. Dipalmitoyl phosphatidylcholine (a.k.a. lecithin) is a major component of pulmonary surfactant and is often used in the L/S ratio to calculate fetal lung maturity. While phosphatidylcholines are found in all plant and animal cells, they are absent in the membranes of most bacteria, including ''Escherichia coli''. Purified phosphatidylcholine is produced commercially. The name ''lecithin'' was derived from Greek λέκιθος, ''lekithos'' 'egg yolk' by Theodore Nicolas Gobley, a French chemist and pharmacist of the mid-19th century, who appli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dipalmitoylphosphatidylcholine
Dipalmitoylphosphatidylcholine (DPPC) is a phospholipid (and a lecithin) consisting of two C16 palmitic acid groups attached to a phosphatidylcholine head-group. It is the main constituent of pulmonary surfactants, which reduces the work of breathing and prevents alveolar collapse during breathing. It also plays an important role in the study of liposomes and human bilayers. Lung surfactant Lung surfactant (LS) is a surface-active material produced by most air-breathing animals for the purpose of reducing the surface tension of the water layer where gas exchange occurs in the lungs, given that the movements due to inhalation and exhalation may cause damage if there is not enough energy to sustain alveolar structural integrity. The monolayer formed by the LS on the interface is composed primarily of phospholipids (80%), in addition to proteins (12%) and neutral lipids (8%). Among the phospholipids, the most prevalent one is phosphatidylcholine (PC, or lecithin) (70–85%), whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
