Antioxidant and antibacterial activity of Buddleja scordioides (Scrophulariaceae) and Flourensia cernua (Asteraceae) extracts

Background and Aims: Buddleja scordioides and Flourensia cernua are plants traditionally used to treat gastrointestinal infection. They belong to the great diversity of medicinal plants in Mexico. The objective of this research was to determine the minimum inhibitory concentration (MIC) and phytochemical compound profile of hydroalcoholic extracts of Buddleja scordioides and Flourensia cernua.Methods: MIC was evaluated against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, and Candida albicans ATCC 10231. Total polyphenol content (TPC) was quantified using the Folin-Ciocalteu method, total flavonoid content (TFC) using the aluminum chloride colorimetric technique, and antioxidant activity (AA) using DPPH, ABTS, and FRAP. Phytochemical compounds were analyzed using HPLC-MS.Key results: Buddleja scordioides showed moderate inhibition against Candida albicans at 1.87 mg/ml and 7.5 mg/ml, in Staphylococcus aureus and Escherichia coli it showed low inhibition at 15 mg/ml. Meanwhile, Flourensia cernua showed moderate activity against Candida albicans (3.75 mg/ml) and low inhibition against Staphylococcus aureus and Escherichia coli (15 mg/ml). The highest concentration of TPC with 76.37±1.56 mg AGE/g, and in TFC with 42.03±0.98 mg QE/g. The AA of Flourensia cernua in DPPH and FRAP was 132.08±2.23 mg TE/g and 128.01±1.52 mg TE/g, respectively, with higher values than in Buddleja scordioides. Finally, Buddleja scordioides showed a higher value in ABTS with 142.25±19.06 mg TE/g compared to Flourensia cernua. In the identification of phytochemicals, the presence of caffeic acid, quercetin, and hydroxybenzoic acid was detected as components of Buddleja scordioides, and carnosol and gallic acid in the extract of Flourensia cernua.Conclusions: Hydroalcoholic extracts of Buddleja scordioides and Flourensia cernua showed antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Candida albicans. Additionally, a high concentration of polyphenols and flavonoids led to significant antioxidant potential.