Enzyme Inhibitory Activities and RP-HPLC Analysis of <i>Geranium </i>and <i>Erodium</i> Species

The genera Geranium and Erodium (Geraniaceae) have been documented to possess diverse ethnopharmacological uses, including diabetes mellitus. Relevant to their ethnopharmacological use, the current study aimed to evaluate the alpha-glucosidase, alpha-amylase, acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) enzyme inhibitory activity of ethanol extracts from 46 samples belonging to thirty-one species of Geranium (20) and Erodium (11) collected throughout T & uuml;rkiye. The majority of the extracts displayed a marked alpha-glucosidase and alpha-amylase inhibitory activity. Besides, 23 extracts out of 46 exhibited a concentration-dependent inhibitory effect over 50 % towards AChE. The highest AChE inhibition was found in G. subcaulescens collected from Konya with an IC50 value of 4.73 +/- 2.96 mu g/mL. E. somanum, E. leucanthum, and E. sipthorpianum exhibited the most potent alpha-glucosidase inhibitory activity, while E. birandianum and E. pelargoniiflorum were the most active extracts against AChE and BChE, respectively. Three extracts that had inhibitory activity over 50 % against four of the enzymes were selected and proceeded to RP-HPLC analysis. Geraniin and ellagic acid were identified as major compounds in the active extracts. Most species screened in the current study were examined for the first time against alpha-glucosidase, alpha-amylase, AChE, and BChE.