Rethinking Peptones As First-Line Optimization Tools

By Ashwin Gurunathan and Chris Titensor, Thermo Fisher Scientific

Peptones, protein hydrolysates derived from yeast, plant, or animal sources, are valuable yet often overlooked tools for optimizing CHO-based bioprocesses. They can significantly improve culture performance by enhancing cell growth, viability, and protein yield, particularly in processes that have plateaued despite feed or media optimization. By supplying a complex mix of peptides, amino acids, trace elements, and micronutrients, peptones offer functional advantages that chemically defined (CD) media alone may not provide.

Early integration of peptones during screening or medium development can accelerate process optimization, deliver quick titer gains, and extend culture longevity without major process changes. Their nutritional diversity supports robust scalability and reduces risks such as batch variability or rework during tech transfer. Optimal implementation requires careful titration and screening, as over-supplementation can stress cells or disrupt nutrient balance.

Different peptone sources, such as soy, yeast, or cotton, can be evaluated and even blended to maximize benefit and maintain product quality. Case studies have shown that targeted peptone supplementation can more than double IgG titers in CHO cultures, demonstrating their potential to improve productivity, consistency, and cost efficiency. When applied strategically, peptones serve as a powerful complement to CD systems, enabling faster development and more resilient biomanufacturing processes.