Sinem Aslan Erdem ^a, F. Sezer Senol ^b, Esin Budakoglu ^b, Ilkay Erdogan Orhan ^b,*, Bilge Sener ^b

^a Department of Pharmacognosy, Faculty of Pharmacy, Ankara University, Ankara, Turkey
^b Department of Pharmacognosy, Faculty of Pharmacy, Gazi University, Ankara, Turkey

 

The hydroalcoholic extracts of the Turkish traditional coffee samples from 18 commercial brands were tested for their neurobiological effects through enzyme inhibition based on enzyme-linked immunosorbance microtiter assays against acetylcholinesterase, butyrylcholinesterase, and tyrosinase, linked to Alzheimer's and Parkinson's diseases. The extracts were also subjected to several antioxidant test systems to define their antiradical, metal-chelation capacity, and reducing power. Total phenol and flavonoid contents in the extracts were delineated by spectrophotometric methods, while chlorogenic acid in the coffee samples was quantified by high-pressure liquid chromatography. The extracts displayed low to moderate inhibition (from 2.13 ± 0.01% to 36.12 ± 1.07% at 200 μg/mL) against the tested enzymes, whereas they had notable 2,2′-diphenyl-1-picrylhydrazyl radical scavenging activity up to 56.15 ± 2.03% at 200 μg/mL. The extracts exerted a remarkable ferric-reducing antioxidant power values, while chlorogenic acid was found to range between 0.288 ± 0.005% and 2.335 ± 0.010%.

 

Keywords: antioxidant activity, cholinesterase inhibition, chlorogenic acid, high performance liquid chromatography, Turkish coffee