LC-ESI-MS/MS Analysis of Echium asperrimum from the Algerian Aurès Region: Antioxidant, Antimicrobial, Cholinesterase Inhibitory, and Antiproliferative Activities

Abstract

The aim of the present study was to characterize the phenolic profile of hydroethanolic (EAEE) and ethyl acetate (EAAE) extracts of <i>Echium asperrimum</i> and to evaluate their antibacterial, antioxidant, anti-Alzheimer-related (cholinesterase inhibitory) activity, and antiproliferative activities. The DPPH radical scavenging activity of EAEE and EAAE showed IC₅₀ values of 32.53 ± 1.25 and 97.85 ± 2.31 µg/mL, respectively. In addition, both extracts exhibited phosphomolybdenum reduction capacity, with A_0.50 values of 61.60 ± 2.97 µg/mL for EAEE and 23.20 ± 1.55 µg/mL for EAAE. Acetylcholinesterase and butyrylcholinesterase inhibition assays revealed IC₅₀ values comparable to the reference compound galantamine. Both extracts also showed antimicrobial activity against Gram-positive and Gram-negative bacterial strains. LC-ESI-MS/MS analysis indicated that <i>p</i>-coumaric acid (5.12 mg/g), vanillic acid (11.6 mg/g), hydroxybenzaldehyde (3.82 mg/g), and gentisic acid (1.66 mg/g) were the major phenolic constituents of EAAE, whereas <i>p</i>-coumaric acid (0.13 mg/g), salicylic acid (0.141 mg/g), sinapic acid (0.20 mg/g), and trans-ferulic acid (0.20 mg/g) predominated in EAEE. Furthermore, EAAE exhibited dose-dependent antiproliferative activity at concentrations of 50 and 100 µg/mL, with an IC₅₀ value of 83.09 ± 6.50 µg/mL. Taken together, these findings suggest that <i>E. asperrimum</i> represents a promising source of bioactive compounds with potential relevance for future pharmaceutical and nutraceutical research.