Effects of microwave on extracellular vesicles and microRNA in milk

This study demonstrates the effects of microwaves on the microRNA (miRNA) content of milk and milk extracellular vesicles (EV). We determined the miRNA concentration in milk subjected to different treatments using real-time PCR and a spectrophotometer. The miRNA expression and total RNA content of the microwaved milk samples were lower when compared with untreated milk. We measured the microstructure and the size distribution by scanning electron microscopy and dynamic light scattering to verify the loss of miRNA in microwaved milk due to damage to the EV. The results revealed that 2 different-sized EV were present and had an average size of 147.50 and 22.14 nm, respectively. Furthermore, acridine orange staining showed that the total RNA content in microwaved milk EV was lower than that in cow milk. These results suggest that EV may confer the protection and the stability of the miRNA in milk.