HPLC-PDA/ESI-MS Analysis of Phenolic Compounds and Bioactivities of the Ethanolic Extract from Flowers of Moroccan Anacyclus clavatus

Abstract

In this work, polyphenols were extracted from Anacylus clavatus flowers using a hydroethanolic solvent, and the obtained extract was studied for its total phenol and flavonoid contents and evaluated for its antioxidant and antibacterial capacities. The contents of total phenols and flavonoids were measured by employing gallic acid and quercetin as references, respectively, and the phenolic composition analysis was conducted using high-performance liquid chromatography combined with a photodiode array and electrospray ionization mass spectrometry (HPLC-PDA/ESI-MS). The antioxidant capacity of the extracts was tested using a potassium ferric reducing antioxidant power (PFRAP) assay, and the antibacterial activity assay was carried out against Gram-negative bacteria (Escherichia coli and Salmonella typhimirium) and Gram-positive bacteria (Staphyloccocus aureus and Listeria monocytogenes) using the broth microdilution assay. The phenolic and flavonoid contents of the extracts equaled 9.53 ± 0.48 mg GAE/g dm and 1.31 ± 0.06 mg QE/g dm, respectively. The chromatographic analysis of the phenolic profile detected 26 phenolic compounds belonging to phenolic acids, flavones and flavonols, and with the caffeoylquinic acid derivatives being the major phenolic compounds present in 12 isomers. Only one organic compound, viz. citric acid, was found. The extracts exhibited interesting antioxidant activity. Bacteriostatic activity towards Escherichia coli and bactericidal activity against Salmonella typhimirium, Staphyloccocus aureus and Listeria monocytogenes were determined. This study revealed that Anacyclus clavatus flower extracts contain phenolic compounds with interesting bioactivities.