Chinese study finds potato protein peptides can halve serum in cell culture
Researchers at Northwest Minzu University in Lanzhou, China, reported on 5 Nov 2026 that peptides made from potato protein, added at 1 g/L, let MDCK cells grow in medium with 5% newborn calf serum about as well as in the 10% serum control. The paper appeared in Food Science & Nutrition.
Why it matters
Potato protein is a co-product of starch processing, so new uses for it matter to starch plants. Cell culture media could become a higher-value outlet than feed or food. The work is early-stage lab research with no cost or scale-up data, and the peptides could not replace serum completely.
A team at Northwest Minzu University in Lanzhou, China, has tested peptides made from potato protein as a way to cut the amount of animal serum needed to grow cells. The study was published online on 5 Nov 2026 in Food Science & Nutrition (Food Science & Nutrition paper). The tests used MDCK cells, a canine kidney cell line.
How were the peptides made?
The researchers broke down potato protein with enzymes and reached a degree of hydrolysis of 42.83%. They identified 101 peptides, and 66 of them (65.35%) had molecular weights between 500 and 1,000 Da. The hydrolysate also contained 24 free amino acids.
What did the tests show?
The best dose was 1 g of peptides per liter of medium, combined with 5% newborn calf serum. At passage 9 this mix gave an estimated 9.11 × 10⁴ cells/mL and a doubling time of 15.71 hours. The control with 10% serum gave 8.21 × 10⁴ cells/mL and a doubling time of 15.88 hours, a difference the authors found not statistically significant. Serum at 5% without peptides gave 7.19 × 10⁴ cells/mL. The colony-forming rate was 45.1% with peptides, against 43.6% at 10% serum and 39.8% at 5% serum.
In freezing tests, a mix with 15% serum and peptide medium gave cells that looked the same as the control with 20% serum. The authors note, however, that the peptides alone could not replace serum in cryopreservation, and that medium without any serum gave poor cell attachment.
Is there a commercial product?
Not yet. The paper gives no cost, yield or market figures. The authors list standard preparation methods, checks on batch-to-batch consistency and direct cell counts as next steps. Their growth figures come from an indirect assay and are described as approximate.
Key numbers
| Figure | Value | Date | Source |
|---|---|---|---|
| Optimal potato peptide dose | 1 g per liter of medium | 5 Nov 2026 | Source |
| Serum level with peptides vs control | 5 vs 10 % newborn calf serum | 5 Nov 2026 | Source |
| Cell density at passage 9 with peptides | 9.11 × 10⁴ cells/mL | 5 Nov 2026 | Source |
| Degree of hydrolysis | 42.83 % | 5 Nov 2026 | Source |
| Colony-forming rate with peptides | 45.1 % | 5 Nov 2026 | Source |
Sources
- Potato Protein Peptides as a Serum-Reducing Supplement for MDCK Cell Culture Medium · Food Science & Nutrition (Wiley), via PubMed Central (primary source)