ASSESSMENT OF PROTEIN HYDROLYSATES FROM AGRO-INDUSTRIAL WASTES AS AN ALTERNATIVE TO FETAL BOVINE SERUM FOR CELLULAR AGRICULTURE

Protein hydrolysates derived from non-animal agro-industrial wastes have been investigated as sustainable and low-cost alternatives to fetal bovine serum (FBS) in cell culture media within the emerging field of cellular agriculture. FBS is widely used in animal cell culture; however, it represents a major technological and economic bottleneck due to its high cost, batch variability, risk of contamination, and ethical and sustainability concerns. In this context, this study evaluated the potential for partial or total replacement of FBS using protein hydrolysates obtained from soybean meal, corn dried distillers grains with solubles (DDGS), sunflower meal, and brewery yeast waste. The hydrolysates were produced via enzymatic hydrolysis using Alcalase® and Flavourzyme® under optimized conditions, followed by freeze-drying for cell culture application. The effects of the hydrolysates were evaluated in murine myoblast (C2C12) cells by assessing cytotoxicity and cell viability using the MTT assay. For cytotoxicity, cells were exposed to 100, 500, and 2000 μg/mL of hydrolysates in DMEM supplemented with 10% FBS. Cytotoxic effects were observed only for sunflower meal hydrolysates (500 and 2000 μg/mL) and brewery yeast waste hydrolysate at 2000 μg/mL, with significant differences compared to the control (DMEM + 10% FBS) (p < 0.05). For cell viability, the same concentrations were tested with reduced FBS levels (1% and 2.5%). None of the hydrolysates was able to fully replace FBS, confirming its essential role as a complex source of growth factors, hormones, and bioactive compounds required for cell proliferation. However, partial replacement potential was observed, as no statistically significant differences (p < 0.05) were detected between the 10% FBS control and hydrolysate treatments, particularly at 100 and 500 μg/mL with reduced FBS supplementation (2.5%). Notably, the brewery yeast residue hydrolysate exhibited consistent performance at the same tested concentrations, even under reduced FBS supplementation (1%), highlighting its potential for cell culture applications. This finding has prompted further investigations to elucidate the factors underlying its effectiveness. Overall, the results suggest that agro-industrial residue-derived hydrolysates have potential as functional supplements to reduce FBS dependency in cellular agriculture, thereby supporting the development of more sustainable strategies for animal protein production, including cultivated meat.