Cholinesterase, β-amyloid aggregation inhibitory and antioxidant capacities of Chinese medicinal plants

Traditional Chinese medicinal (TCM) plants have a long history of usage in the treatment of different diseases. Neurodegenerative disorder prevention and treatment using TCM have attracted increasing interest in recent year. In current study, the ethanolic extracts of 26 Chinese medicinal plants were prepared, two cholinesterases (ChEs), beta-amyloid aggregation inhibitory, and antioxidant capacities were further investigated for evaluation their anti-Alzheimer's disease (AD) potential as well as total phenolics and flavonoids contents (TPC, TFC). Of these, Polygonum multiflortan and Spatholobus suberectus were the most active ones against acetylcholinesterase (AChE, IC50 = 9.11, 9.27 mu g/mL), butyrylcholinesterase (BChE, IC50 = 4.83, 5.37 mu g/mL), and 2, 2-diphenyl-1-picrilhydrazyl (DPPH, IC50 = 5.69, 3.60 mu g/mL) with highest TPC (267, 377 mg GAE/g dw) and relative higher TFC (80, 594 mg RE/g dw), respectively. The highest activity was observed with the extracts of Rhewn officinale in 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt assay (ABTS, IC50 = 1.60 mu g/mL) and ferric reducing antioxidant power method (FRAP, 5495.43 mu mol Fe2+/g). Meanwhile, both R. officinale and S. suberectus exhibited the strongest inhibition (> 90%) in beta-amyloid peptide (A beta(1-42)) aggregation assay. The present findings may reveal the interesting potential of S. suberectus, P. multiflorum, and R. officinale as a valuable plant source of natural bioactive molecules against AD.