Studies on anticholinesterase and DPPH radical scavenging effects of 41 species of Fritillaria L. genus of Turkish origin

The genus Fritillaria L. (Liliaceae) is a member of geophytes with attractive flowers, which are cultivated as ornamental plants. Many of the European Fritillaria species are found in the Alps, the Pyrenees, the Balkans, and northern Turkey. There are 41 Fritillaria species growing in Turkey, 26 of which are endemic. The research carried out on Fritillaria species are focused on the alkaloid content of the plant.

In the present study, the dichloromethane and methanol extracts prepared from the bulbs of 59 samples belonging to 41 Fritillaria cultivated in Turkey have been investigated for their cholinesterase inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), the enzymes linked to Alzheimer's disease, at 50, 100, and 200mg mL-1 using ELISA microplate reader. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging effect of the extracts was also tested 12.5, 25, and 50mg mL-1 final concentrations. According to our results; the highest inhibition against AChE was caused by the dichloromethane and methanol extracts of F. persica L. (21.03±0.34% and 27.39±2.26%, respectively). The most active extracts against BChE were found as the dichloromethane extract of F. pinardii Boiss. (49.72±2.56%) and two samples of F. persica (48.27±1.98% and 47.29.±1.72%). Among the methanol extract, the best BChE inhibitions were found to be caused in F. minima Rix (54.69±3.40%), F. persica (51.85±4.68%), and F. caucasica J.F. Adam (46.14±2.96%). On the other hand, all of the extracts displayed low profile of DPPH scavenging effect below 25%. The present results indicate that especially F. persica could be a potential source of natural compounds with anticholinesterase effect.

Keywords: Fritillaria, anticholinesterase activity, free radical scavenging effect