Phenolic Acid Profile and In Vitro Antioxidant and Anticholinesterase Activities of Romanian Wild-Grown Acer spp. (Sapindaceae)

This study investigated, for the first time, the phenolic acid profile along with the in vitro antioxidant and acetylcholinesterase (AChE) inhibitory activities of leaves and fruits from five Romanian wild-grown Acer spp. (Sapindaceae): A. campestre L., A. monspessulanum L., A. platanoides L., A. pseudoplatanus L., and A. tataricum L. High-performance liquid chromatography coupled with ultraviolet and mass spectrometry (HPLC/UV/MS) was employed to identify and quantify key phenolic acids, including gallic, caffeic, protocatechuic, chlorogenic, and p-coumaric acids. Total phenolic content (TPC) ranged from 61.48 ± 3.76 to 512.8 ± 20.54 µg gallic acid equivalents (GAE)/mL. Antioxidant activities, assessed through 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays, demonstrated the strongest radical scavenging capacities for A. tataricum fruits, with half maximal inhibitory concentration (IC50) values of 10.88 ± 3.39 µg/mL and 10.39 ± 2.86 µg/mL, respectively. The ferric-reducing antioxidant power (FRAP) assay revealed the highest reducing power for A. tataricum fruits (1158 ± 48.98 µmol Fe2+/L) and leaves (1119 ± 164.6 µmol Fe2+/L). AChE inhibition was only found in A. tataricum, with an IC50 of 7.91 ± 7.50 mg/mL for leaves and 15.95 ± 8.52 mg/mL for fruits. These results highlight A. tataricum as a promising source of natural antioxidants and neuroprotective agents.