Neuroprotective potential of Viburnum orientale Pallas through enzyme inhibition and antioxidant activity assays

Neurobiological effects of the fruit, leaf, and branch extracts of Viburnum orientale, used in the traditional drink called “gilaburi” in Anatolia, were tested against acetyl- (AChE), butyrylcholinesterase (BChE), and tyrosinase (TYR). Antioxidant effect of the extracts was determined using six in vitro methods. The fruit and branch methanol extracts with the richest total phenolic contents exerted the highest inhibition against all enzymes. These extracts were the most active in DPPH radical scavenging, ferric- (FRAP) and phosphomolibdenum-reducing antioxidant power (PRAP) assays, which was followed by the leaf aqueous extract with the best nitric oxide (75.00 ± 1.22%), DMPD scavenging (33.70 ± 1.13%), and metal-chelating (54.66 ± 3.56%) effects at 2500 μg/mL. We previously reported that the fruits are rich in chlorogenic acid, which might be related to its marked enzyme inhibitory and antioxidant effect. Our results indicated that all methanol and leaf aqueous and branch extracts of the plant are promising for their neuroprotective potential.