The Volatile Chemical Compositions of the Essential Oil/SPME and Enzyme Inhibitory and Radical Scavenging Activities of Solvent Extracts and the Essential oils from Coronilla orientalis Miller and C. varia L. grows in Turkey

The volatile organic compounds (VOCs) of two Coronilla species (Coronilla orientalis Miller and Coronilla varia L.) obtained by hydrodistillation (HD) and solid phase microextraction (SPME) techniques were identified by GC-FID/MS. The major compounds identified in the SPME extracts were limonene (43.4%) in C. orientalis, (Z)-β-ocimene and (E)-β-ocimene (34.3% and 32.4%) in C. varia, whereas, the essential oils of C. orientalis and C. varia were rich with γ-terpinene (22.4%) and phytol (30.7%), respectively. In addition, acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), tyrosinase, α-glucosidase enzyme inhibitory, and radical scavenging activities (DPPH) of chloroform, ethyl acetate, methanol, and water extracts, and also essential oils obtained from C. orientalis and C. varia were investigated. The tyrosinase activity was studied at the doses of 25 µg/mL, 50 µg/mL and 100 µg/mL. Tyrosinase inhibition percentage was observed to increase by dose and methanol extracts of the both species were found to have the highest activity. Essential oils of the both species were found to have significant acetylcholinesterase and butyrylcholinesterase inhibition activities. α-Glucosidase enzyme inhibition of the ethyl acetate and water extracts of C. orientalis was determined as 80.11 ± 4.07% and 80.32 ± 3.47% at the 100 µg/mL concentration, respectively. Essential oils, chloroform, ethyl acetate, methanol, and water extracts were determined to have moderate DPPH radical scavenging activities.