The Protein Man's Blog | A Discussion of Protein Research

When working on proteins, your sample biological materials should first be homogenized to ensure proper solubilization and extraction. This can be a challenge if you are trying to extract plant proteins because their tissues contain significant amounts of proteases, phosphatases and glycosidases which can interfere with the results. In addition, not all biological materials require the same technique so you should really be careful when choosing the technique that you would use.

Extracting proteins from plants is not the same as extracting proteins from animal sources. There is a very different set of factors that you will need to consider in order to properly process plant proteins. This post explores some of the key ways in which plant-based protein extraction differs from animal-based protein extraction, and details some of the ways you can overcome these differences.

Proteins are highly heterogeneous, complex bio macromolecules consisting of one or more long chains of amino acids. Proteins or peptides fold up to form secondary and tertiary structures, and associate with other protein subunits to form quaternary structures. Proteins are structurally and functionally different from each other and require distinct surrounding environment for their stability and activity. Proteins are susceptible to degradation, denaturation and precipitation when taken out of their native environment.

Extraction of proteins from cells and tissue of organisms is the first step towards isolation of proteins. The extracellular matrix needs to be removed or digested in case of tissue, the cell wall needs to be digested for organisms like bacteria, yeast and plants, and the cell membrane needs to be disrupted to release the proteins in solution. Traditionally, physical methods for disruption of cells and tissues are employed to release cellular proteins including sonication, french press, homogenization, manual grinding or using blenders.  Although one is able to get the active proteins, these physical methods have several limitations: