Find in Library

This study aimed to investigate the polyphenolic composition and antioxidant and antimicrobial potential of six Romanian Stachys species: <i>S. officinalis</i>, <i>S. germanica</i>, <i>S. byzantina</i>, <i>S. sylvatica</i>, <i>S. palustris</i>, and <i>S. recta</i>. The LC-MS/MS method was used to analyze the polyphenolic profile, while the phenolic contents were spectrophotometrically determined. The antioxidant activity was evaluated using the following methods: DPPH, FRAP, nitrite-induced autooxidation of hemoglobin, inhibition of cytochrome <i>c</i>-catalyzed lipid peroxidation, and electron paramagnetic resonance spectroscopy. The in vitro antimicrobial properties were assessed using agar-well diffusion, broth microdilution, and antibiofilm assays. Fifteen polyphenols were identified using LC-MS and chlorogenic acid was the major component in all the samples (1131.8–6761.4 μg/g). <i>S. germanica</i>, <i>S. palustris</i>, and <i>S. byzantina</i> extracts each displayed an intense antiradical action in relation to high contents of TPC (6.40 mg GAE/mL), flavonoids (3.90 mg RE/mL), and caffeic acid derivatives (0.89 mg CAE/mL). In vitro antimicrobial and antibiofilm properties were exhibited towards <i>Candida albicans</i>, Gram-positive and Gram-negative strains, with the most intense efficacy recorded for <i>S. germanica</i> and <i>S. byzantina</i> when tested against <i>S. aureus</i>. These results highlighted Stachys extracts as rich sources of bioactive compounds with promising antioxidant and antimicrobial efficacies and important perspectives for developing phytopharmaceuticals.