Improved antibacterial potencial of Cistus salvifolius aerial parts on skin pathogens by optimization of cold and hot water extraction

Cistus salvifolius is one of the most spread Cistus species in Cyprus and is a plant rich in phenolic compounds, associated with potent antimicrobial effects [ 1 ]. There is accumulated knowledge for the inhibitory effects of Cistus salvifolius on clinical and foodborne bacteria [ 2 ]. Previous studies also reported the antimicrobial potential of Cistus plants on skin pathogens such as Staphylococcus aureus and Pseudomonas aeruginosa [ 3 ]. The aim of the present work was to optimize cold and hot water extraction of antimicrobial substances from Cistus salvifolius using response surface methodology improving the antimicrobial potency against two common skin pathogens. In particular, the effects of extraction temperature, extraction time and water to plant material ratio on total phenolics, total flavonoids, total tannins and the inhibition of growth of Staphylococcus aureus and Pseudomonas aeruginosa expressed as optical density were studied using Box-Behnken designs. According to the desirability index, the highest antimicrobial potency could be obtained by extraction plant material at 7°C or 88°C for 300 or 13 min by mixing water and plant material at a ratio of 125 mL per g for cold and hot water extraction, respectively. Subsequently, minimum inhibitory and minimum bactericidal concentrations as well as drug-enhancing and biofilm formation inhibition activity were also determined for both extracts. Overall, the present study demonstrates the potential of aqueous extracts of Cistus salvifolius to control the growth of skin pathogens and delivers guidelines for the preparation of cold and hot and cold water extracts. Publication History Article published online: 05 March 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany