UHPLC-MS/MS chemical profiling, preliminary toxicity, in vitro antioxidant potential and antimicrobial activity of Brachyotum naudinii Triana flowers

Abstract

Chemical compounds of Brachyotum naudinii Triana flowers were analyzed using UHPLC-MS/MS. Anthocyanin dry extract was obtained by accelerated solvent extraction with 70% ethanol acidified with citric acid (pH 3.18) and then spray dried. Preliminary toxicity of anthocyanin extract was evaluated using Artemia salina Leach, while its antioxidant capacity was measured by DPPH• and ABTS•+ methods, and reducing capacity was assessed using FRAP assay. Results showed the flowers comprise 39% tannins, 21% flavonol glycosides, 14% organic acids, 11% anthocyanins, 7% coumaric acid derivatives, 4% polar lipids, and 4% disaccharides. Anthocyanin extract exhibited moderate toxicity against Artemia salina (LC50 = 106.9 ± 9.9 µg mL−1) and showed inhibitory effects on DPPH• and ABTS•+ radicals, as well as reducing capacity in FRAP assay, though statistically different from Trolox (p < 0.05). The flowers have demonstrated antimicrobial activity against Staphylococcus aureus and are a source of novel anthocyanin compounds with antioxidant potential.

Keywords

• Melastomataceae
• endemic species of rocky outcrops
• LC-MS/MS
• new bioactive compounds
• antioxidant potential
• Artemia salina Leach