Characterization of electrospun Aronia melanocarpa fruit extracts loaded polyurethane nanoweb

In this study, Aronia melanocarpa fruit was extracted with ethanol, distilled water (pH 7), acidified distilled waters (at pH 5 and 3) as the solvent, the total polyphenol content, total flavonoid content, and anti-oxidant activity of the extracts were analyzed. Then, we investigated the possibility of producing nanofibers by the electrospinning process by adding the Aronia melanocarpa fruit extract (AE), which showed the greatest antioxidant effect, to a polyurethane (PU). The electrospinning method used a PU concentration of 10 wt% and 12 wt%, an applied voltage of 10 kV, a tip-to-collector distance of 15 cm, and flowrate of 0.3 mL/h. The analysis confirmed that the total polyphenol, total flavonoid content, and antioxidant activity of the distilled water extract were the highest at a pH value of 3. As the AE was added and its concentration increased, both the viscosity and the diameter of the nanofibers also increased. At PU concentrations of 10%, 12%, relatively uniform nanofibers without beads were prepared by adding 2 to 3 wt% and 0.5 to 2 wt% of the AE, respectively. At the above conditions, the diameters of the nanofibers that were produced were in the range of 227 to 420 nm, so it was evident that PU/AE nanofibers with various diameters could be prepared by controlling the concentration of PU and AE. In addition, the FT-IR, XRD, and DSC analyses confirmed that hydrogen bonding occurred between the AE and the PU. Thus, the resulting crystallinity, melting point, and reduction in the heat capacity confirmed that the AE was well mixed with the PU polymer.

Automated summary

This study investigated the antioxidant properties of Aronia melanocarpa fruit extracts and explored the possibility of producing nanofibers by incorporating the extract into polyurethane. The results showed that acidified distilled water extract at a pH of 3 exhibited the highest antioxidant activity. Additionally, by controlling the concentrations of PU and AE, nanofibers with different diameters could be successfully prepared. Furthermore, FT-IR, XRD, and DSC analyses confirmed the interaction between AE and PU, indicating a good mixing of the two components.