Anticholinesterase Activities of Selected Polyphenols – a Short Report

Abstract

In this work, anticholinesterase activities of 24 polyphenolic compounds were tested using the modified Ellman's spectrophotometric method. The most efficient acetyl-and butyrylcholinesterase inhibitors were anthocyanins (pelargonidin, delphinidin and cyanidin), flavones (apigenin and luteolin), flavonols (quercetin, kaempferol and myricetin), as well as dihydrochalcone phloridzin and prenylated chalcone xanthohumol. It was established that all the tested compounds were within a narrow molecular weight range of 254.24-354.40 g/mol, which probably was not discriminative for their inhibitory activity. Among all the classes of polyphenolic compounds, the lowest activities were exerted by flavan-3-ols. The inhibitory activity of the tested polyphenols was decreased by the presence of a 3-hydroxyl group. A simultaneous substitution of a carbonyl group at position 4 and a hydroxyl group at position 3 or a lack of both of these substitutions had no effect on the activity of the investigated compounds. The number and position of other hydroxyl groups in the tested molecules played a minor role in this context. Aglycons were more effective cholinesterase inhibitors than their corresponding glycosylated forms. Overall, the results show that phenolic acids can play a role in neuroprotection. However, further in vitro and in vivo studies involving a larger number of polyphenolic compounds simultaneously with well-known cholinesterase inhibitors should be performed in the nearest future to confirm these findings. Unauthenticated Download Date | 5/8/18 4:25 AM

Anticholinesterase activity of selected phenolic acids and flavonoids – interaction testing in model solutions

“…Phenolic compounds were chosen for testing, based on previous studies [2,6,18]. The results obtained in the current study confirm the in vitro anticholinesterase activity of these compounds.…”

“…Anthocyanins pelargonidin (PEL), delphinidin (DEL) and cyanidin (CYA), flavones apigenin and luteolin, flavonols quercetin (QUE), kaempferol (KAE) and myricetin (MYR), dihydrochalcone phloridzin (PHL) and prenylated chalcone xanthohumol are the most efficient in vitro inhibitors of AChE and/or BChE in a study testing 24 polyphenols. The lowest inhibitory activity is exerted by flavan-3-ols [6]. Flavonoids inhibit the formation and extension of amyloid-β (1 -40) or (1 -42) fibrils (in decreasing order: MYR = morin = QUE > KAE > (+)-catechin = (-)-epicatechin [7].…”

Phytochemical Analysis, Antioxidant, Antistress, and Nootropic Activities of Aqueous and Methanolic Seed Extracts of Ladies Finger (Abelmoschus esculentusL.) in Mice

“…Many plant derived phytochemicals claimed for nootropic activity have shown AChE inhibitory effect and/or antioxidant activity [59]. To our knowledge, based on thorough literature search, there was no report on AChE inhibitory effect of Abelmoschus esculentus .…”

Acetylcholinesterase and carbonic anhydrase isoenzymes I and II inhibition profiles of taxifolin

“…Carbamate pesticides show their toxicity by irreversibly modifying the catalytic serine residue of AChE, and the inhibiting the AChE 67 . Recently, several studies supported that many active compounds from plant origins, including anthocyanins and terpenoids have AChE inhibition activity 68,69 . Additionally, some studies demonstrated that grape and blueberry anthocyanin 70,71 , grape skin anthocyanin 72 lycodine-type alkaloids from Lycopodiastrum casuarinoides 73 have neuroprotective roles.…”