Folch+Lipid+Extraction

This reliable extraction technique is used to separate lipid molecules from the rest of the cell. A 2:1 solution of chloroform/methanol is used to extract lipids from the biomaterial. The crude solvent is then washed with 0.2 volume of its water and filtered to separate the phases(Folch, Lees, & Stanley, 1957).

The purification of lipids, the main components of the cell membrane, is necessary in order to perform any other analysis on the composition or function of these components.

__History__: The Folch extraction method is named for its creator. Jordi Folch (1911-1979) was a medical doctor who made many contributions to neurochemistry research throughout his career. He developed this method for isolating lipids in 1956 after having worked to improve lipid extractions for many years (Leray 2013). It was a major advancement which allowed Folch to study the changes in lipids during brain diseases and lead his discovery of myelin proteolipid and gangliosides (Leray 2013).

__Examples of Use__: In 2012, a modified version of the Folch method was found to have comparable results to three other common methods of lipid extraction, the International Organization for Standardization method; the Association of Official Analytical Chemists (AOAC) method and an AOAC method using a lower solvent volume (Taha, Metherel, & Stark, 2012). It was found that smaller sample sizes and smaller volumes of solvent with longer incubation time during the extraction produces the greatest yield of lipids for the Folch method (Taha et al., 2012). In 2011, methods for extraction of lipids from macroalgae, a group of organisms important in food and industry, showed that by modifying the Folch method by adding a phosphate buffer to the extraction solvent, a higher yield of lipids was achieved (Kumari, Reddy, & Jha, 2011). In 2013, a study was done that showed that lipid extraction using the Folch technique from macroalgae could be improved by as much as 50% (Bai et al., n.d.)by adding silver nanofibers to the extraction. This however did appear to affect the structure of the lipids which were extracted causing incorrect results.

__References__: Bai, R., Silaban, A. G., Teresa Gutierrez-Wing, M., Benton, M. G., Negulescu, I. I., & Rusch, K. A. (n.d.). Silver nanofiber assisted lipid extraction from biomass of a Louisiana Chlorella vulgaris/Leptolyngbya sp. co-culture. //Chemical Engineering Journal//. doi:10.1016/j.cej.2013.03.075 Folch, J., Lees, M., & Stanley, G. H. S. (1957). A Simple Method for the Isolation and Purification of Total Lipides from Animal Tissues. //Journal of Biological Chemistry//, //226//(1), 497–509. Kumari, P., Reddy, C. R. K., & Jha, B. (2011). Comparative evaluation and selection of a method for lipid and fatty acid extraction from macroalgae. //Analytical Biochemistry//, //415//(2), 134–144. doi:10.1016/j.ab.2011.04.010 Leray, Claude. (2013 3–13). Folch Bibliography. //Cyberlipid Center//. Retrieved from [] Taha, A. Y., Metherel, A. H., & Stark, K. D. (2012). Comparative analysis of standardised and common modifications of methods for lipid extraction for the determination of fatty acids. //Food Chemistry//, //134//(1), 427–433. doi:10.1016/j.foodchem.2012.02.087