Phytochemical analyses with LC-MS/MS and in vitro enzyme inhibitory activities of an endemic species Allium stylosum O. Schwarz (Amaryllidaceae)

In the present work, the chemical profile of an endemic Allium stylosum O. Schwarz was examined for the first time. In this framework, 28 phenolic constituents were detected in methanol extracts of bulbs, leaves and flower parts both by qualitative and quantitative LC-ESI-MS/MS analyses. The benzoic acid derivative gallic acid was detected with a quantity of 988.0 +/- 6.21 mg g(-1), the highest amount for any compound in the leaf sample of A. stylosum from Manisa (AS-2L). (-)-Epigallocatechin gallate (279.4 +/- 1.62 mg g(-1) of extract) was the most abundant of the flavonols present in leaf samples collected in Izmir (AS-1L). Additionally, these extracts were subjected to in vitro enzyme inhibition assays including acetylcholinesterase (AChE), butyrylcholinesterase (BuChE) and tyrosinase. AS-2L displayed the most potent inhibition with IC50 values of 23.95 +/- 0.08 and 8.95 +/- 1.24 mg/ml against AChE and BuChE, respectively, while AS-1L showed the best inhibition against tyrosinase (IC50 49.87 +/- 1.31 mg/ml). Also, the correlations between polyphenolic composition and the biological results were interpreted and these were supported by principal component analysis. (C) 2020 SAAB. Published by Elsevier B.V. All rights reserved.

Automated summary

The chemical profile of the endemic plant Allium stylosum O. Schwarz was examined for the first time, revealing a variety of phenolic constituents with gallic acid and (-)-epigallocatechin gallate being the most abundant. These extracts showed potential medicinal value in in vitro enzyme inhibition assays, highlighting the importance of further exploration into their therapeutic properties.