Effect of Microwave and Ultrasound-Assisted Extraction on the Phytochemical and In Vitro Biological Properties ofWillow (Salix alba) Bark Aqueous and Ethanolic Extracts Alemán, Ricardo S. Duque Soto, Carmen Lozano Sánchez, Jesús Phytochemistry Antioxidant Anti-inflammatory Medicinal plants Acetylcholinesterase inhibition White willow (Salix alba) is a medicinal plant used in folk medicine. In this study, aqueous and ethanolic willow bark extracts were obtained via ultrasonic-assisted extraction (UAE) and microwave-assisted extraction (MAE), and analyzed regarding their phytochemical (total phenolics, phenolic acids, flavonoids, and tannins) content and in vitro biological properties (antibacterial and antifungal activity, acetylcholinesterase AChE inhibitory activity and anti-inflammatory effects). The highest phenolic, tannin, and flavonoid contents were found for willow bark extracts obtained via microwave-assisted extraction using ethanol as a solvent (SA-ME). The polyphenol load of all MAE and UAE extracts was higher when conventional solid–liquid extraction was applied (r < 0.05). The antioxidant capacities were stronger for microwave-assisted ethanolic extracts, with the lowest IC50 values of 12 g/mL for DPPH and a value of 16 g/mL for ABTS +, whereas the conventional extraction had the highest IC50 values (22 g/mL and 28 g/mL, respectively). Willow bark extract showed antibacterial activity against Gram-positive bacteria S. aureus and P. aeruginosa. AChE inhibitory activity was dependent on the extraction method and solvent used, and the highest inhibition among samples was observed for SA-ME. Taken altogether, our findings suggest that willow (Salix alba) bark extract obtained via ethanolic microwave-assisted extraction is a phytochemical-rich resource with in vitro, anti-inflammatory, and AchE inhibitory properties and, therefore, potential multiple medicinal end-uses. 2023-09-26T08:37:11Z 2023-09-26T08:37:11Z 2023-07-03 journal article Aleman, R.S.; Marcia, J.; Duque-Soto, C.; Lozano-Sánchez, J.; Montero-Fernández, I.; Ruano, J.A.; Hoskin, R.T.; Moncada, M. Effect of Microwave and Ultrasound-Assisted Extraction on the Phytochemical and In Vitro Biological Properties of Willow (Salix alba) Bark Aqueous and Ethanolic Extracts. Plants 2023, 12, 2533. [https://doi.org/10.3390/plants12132533] https://hdl.handle.net/10481/84658 10.3390/plants12132533 eng http://creativecommons.org/licenses/by/4.0/ open access Atribución 4.0 Internacional MDPI