Initial product concentration

The next phase of downstream processing usually entails concentration of the crude protein product. This yields smaller product volumes, which are more convenient to work with and can be subsequently processed with greater speed. Concentration may be achieved by inducing product precipitation using salts, such as ammonium sulfate, or solvents, such as ethanol. The precipitate is then collected (usually by centrifugation, but potentially also by filtration) and the precipitate is redissolved in a small volume of processing buffer. Ion-exchange chroma-tography (in which proteins bind to charged beads immobilized in a column) can also potentially be used to concentrate protein solutions. This is discussed later in this chapter. Both of these methods also result in limited protein purification, as not all protein types present in the crude preparation will co-precipitate or bind to the ion exchanger along with the target protein. Ultrafiltration, however, is by far the most common method now used to achieve initial product concentration.

Supplements For Diabetics

Supplements For Diabetics

All you need is a proper diet of fresh fruits and vegetables and get plenty of exercise and you'll be fine. Ever heard those words from your doctor? If that's all heshe recommends then you're missing out an important ingredient for health that he's not telling you. Fact is that you can adhere to the strictest diet, watch everything you eat and get the exercise of amarathon runner and still come down with diabetic complications. Diet, exercise and standard drug treatments simply aren't enough to help keep your diabetes under control.

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