Discovery of potent in vitro neuroprotective effect of the seed extracts from seven Paeonia L. (peony) taxa and their fatty acid composition

Neuroprotective effect of the seed ethanol extracts of seven Anatolian Paeonia L. taxa (P. arietina, P. × kayae, P. mascula subsp. bodurii and subp. mascula, P. daurica, P. peregrina, and P. tenuifolia) was determined in vitro via acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase (TYRO) inhibition using ELISA microtiter plate assays. Their antioxidant effect was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), N,N-dimethyl-p-phenylendiamine (DMPD), and nitric oxide (NO) radical scavenging activity, metal-chelation capacity, and ferric-reducing antioxidant power (FRAP) assays. Total phenol and flavonoid quantification of the extracts was calculated spectrophotometrically. Fatty acid composition of the seed oils was also determined. The extracts displayed potent inhibition against AChE and BChE and marked TYRO inhibition, while they showed low to moderate activity in the antioxidant tests. The oils were found to have similar fatty acid compositions which are rich in oleic, linoleic, and linolenic acids, with exception the seed oil of P. mascula subsp. bodurii.