ダウンストリーム処理

Downstream processing begins after the production stage to recover and purify products like acids, vitamins, or antibiotics.

Centrifugation is often used as the initial step to separate cells from the medium.

For extracellular products, the supernatant is collected after centrifugation.

For intracellular products, cells are disrupted by homogenization to release their contents.

The resulting mixture is then clarified to remove solid debris using techniques like filtration, producing the crude product.

This crude product undergoes primary purification. For example, ammonium sulfate precipitation is commonly used for many protein-based products.

The precipitated product is concentrated using ultrafiltration.

Here, transmembrane pressure is applied to separate molecules by size, retaining the larger target proteins while smaller molecules pass through.

Affinity chromatography then isolates the target protein, yielding a purer product.

Finally, the purified product is stabilized through formulation, which may include adjusting pH, adding stabilizers, or lyophilizing the product.