Comparison of the extraction efficiency of phytochemicals from plants used to support respiratory system function

The COVID-19 pandemic has contributed to long-term complications and general population-level weakening of the respiratory system. This situation encourages the search for natural preventive, regenerative methods to support standard therapies used for respiratory system disorders. Herbs have long been recognized as sources of health-promoting compounds. Given that many disorders involve secondary oxidative stress, the antioxidant properties of phytochemicals are especially valuable. The present study compared different extraction methods (infusions, two types of decoctions, and macerates) to optimize their parameters to maximize yield and efficacy of phytochemicals in extracts. Based on a literature review and medical consultations, ten species of safe plants (with no known interactions with conventional drugs) traditionally used in the prevention and supportive treatment of respiratory diseases were selected ( Althaea officinalis, Ammi visnaga, Plantago lanceolata, Pulmonaria officinalis , Thymus serpyllum, Thymus vulgaris, Tussilago farfara, Verbascum densiflorum , Veronica officinalis, Viola tricolor ). In the obtained extracts, total polyphenols were assayed, and multidirectional antioxidant ability was assessed using ABTS, FRAP, and FeMICA tests. Results indicated that the choice of optimal extraction method largely depends on the types of herbal material used. The optimal technique variants varied among the plant species studied, but it was generally observed that decoction was found to promote higher polyphenol content, enhance the reducing power, and improve free radical scavenging properties. However, high-temperature methods significantly reduced the chelating activity of the extracts. Full results and recommendations will be presented in a poster session. The research purposefully focused on simple, average user-accessible extraction methods to maximize the therapeutic potential of herbal raw materials used by patients with respiratory system disorders. Funding : The research project is financed by the Minister of Education and Science under the program Science for Society II (NdS-II/SP/0390/2023/01), as well as by the University of Lodz, including the Faculty of Biology and Environmental Protection. Publication History Article published online: 05 March 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany