Achieving Lasting Umbilical Cord Decontamination and Sustainable Stem Cell Sourcing by Combining Plasma-Functionalized Liquid and Ultrasound

The growing demand for alternative meat products is accelerating research into reproductive cell sources for cell-based meat processes, also called cultured meat. Porcine umbilical cord tissue is recognized as an advantageous source of mesenchymal stem cells (MSCs). However, effective decontamination must be achieved without compromising tissue integrity and cell recovery. In this study, we evaluated the decontamination of porcine umbilical cords using plasma-functionalized liquid (PFL) generated by a microwave-driven plasma source. It was applied alone and in combination with ultrasound, with the combined approach demonstrating superior performance. Specifically, the ultrasound-PFL combination treatment reduced the initial microbial load of individual tissue samples, ranging from 4.08 to 7.41 log₁₀ CFU/g, approaching the limit of detection of the applied microbiological assays. Statistical analysis indicated a significant contribution of both PFL and ultrasound to microbial reduction, while mesenchymal stem cell yields (5.4 × 10⁵ cells/g tissue) and cell viability (84%) remained comparable to antibiotic-rinsed controls. Recovered cells retained functional capacity, as demonstrated by successful 3D spheroid formation. These results highlight ultrasound-assisted PFL rinsing as an efficient, long-lasting, and antibiotic-free decontamination strategy without compromising tissue compatibility. This study thereby extends the application of plasma-functionalized liquids and demonstrates the feasibility of sustainable stem cell sourcing. It offers opportunities in cultured meat bioprocessing.