Recycling of bioresource by-products for the production of cell culture media: research trends and prospects

Cell culture technology underpins biopharmaceutical production, cultured meat, cell therapy, and regenerative medicine. However, the high cost, ethical concerns, safety issues, and batch-to-batch variability of cell culture media remain major barriers to industrialization, highlighting the need for sustainable alternatives. Meanwhile, tons of agricultural by-products are generated annually worldwide and may serve as valuable resources in a circular economy. This review systematically categorizes agricultural by-products into livestock, seafood, plant, and secondary processing groups and evaluates their potential roles in basal media, serum substitutes, growth factors, antibiotic alternatives, scaffolds, and functional additives. Livestock-derived sera and plasma proteins support proliferation comparable to FBS, while fish collagen peptides and microalgal extracts show growth factor-like activity and scaffold potential. Plant protein hydrolysates are already used in large-scale production, and yeast extracts and whey hydrolysates can support serum replacement and media recycling. Despite these advances, challenges remain in compositional variability, long-term safety, scale-up validation, and regulatory standardization. This study introduces a cross-functional applicability matrix that maps by-product sources to specific media functions, providing an integrated framework for material selection and a commercialization-level assessment to evaluate industrial feasibility. Overall, this review provides a comprehensive assessment of agricultural by-products as promising resources for next-generation cell culture media.