The antioxidant activity of the Calluna vulgaris (L.) Hull. extracts obtained by supercritical CO2 extraction

Abstract

Calluna vulgaris (L.) Hull. is an evergreen perennial plant of the Ericaceae family possesses noteworthy pharmacological properties and has long been used in traditional medicine for addressing many medical conditions [1]. A plethora of bioactive compounds have been discovered in C. vulgaris, with phenolics being the primary source of its diverse health benefits, including antioxidant, anti-inflammatory, and antimicrobial properties, among others [2, 3]. However, a detailed study of its antiradical activity has not been conducted before. Herein, the supercritical CO2 extraction of C. vulgaris branches has been employed to obtain an extract rich in polyphenolic compounds. Supercritical CO2 extraction, a green technology method, replaces classical solvent-based extraction, enabling the isolation of plant compounds in their purest form without degradation of the sample [4]. Owing to its high sensitivity and specificity, Electron paramagnetic resonance (EPR) spectroscopy has been utilized to access the extract's scavenging activity against free radical species (DPPH and hydroxyl radicals). The spin-trapping technique was employed to detect activity against short-lived hydroxyl radicals. The results demonstrate that the C. vulgaris branch extract is a significant free-radical scavenger. It exhibited remarkable selectivity in eliminating hydroxyl radicals (68.5% compared to 21.7% for DPPH), which is particularly noteworthy as hydroxyl radicals are considered the most reactive oxygen radical species, biologically relevant, and responsible for a number of pathologies. These findings underscore the therapeutic potential of C. vulgaris branch extract in combating oxidative stress-related medical conditions but also suggest possibilities for further investigation into its mechanism of action and formulation into pharmaceutical or nutraceutical products.