We are pleased to invite you to attend the dissertation thesis defence of Julien Antih on “Chemical composition and antibacterial activity of essential oils vapours from plants recommended by the European Medicines Agency against respiratory diseases” (Department of Crop Sciences and Agroforestry, Tropical Agrobiology and Bioresource Management). Thesis defence will take place on 12.1.2024 at 10:30 AM, Meeting Room 313 FTA.
Often used as a synonym for pneumonia, lower respiratory tract infections remain among the leading causes of morbidity and mortality worldwide. Antibiotic inhalation therapy, a method involving the precise delivery of aerosolized particles directly into the lungs, offers distinct advantages over systemic antibiotics. However, challenges in executing effective nebulization techniques, coupled with the lack of robust clinical data, have constrained its broader application, especially in cases of lower respiratory tract infections in children under five. In this context, the volatile constituents of essential oils (EOs) appear as a promising alternative in the development of novel inhaled antibiotic therapy. The purpose of this study was first to determine the in vitro antibacterial activity of five EOs recommended by the European Medicines Agency against respiratory infections. The EOs obtained from three commercial samples of Eucalyptus globulus, Foeniculum vulgare, Mentha x piperita, Pimpinella anisum, and Thymus vulgaris were assessed using broth microdilution volatilization method against three standard bacterial strains associated with pneumonia, including Staphylococcus aureus, Streptococcus pyogenes and Haemophilus influenzae. With the aim to optimize a protocol for characterizing EO vapours, we initially determined the chemical profile of the most active EO (T. vulgaris) using dual column/dual detector gas chromatography system. Subsequently, a thorough characterization of the vapour composition was conducted through headspace analyses above a liquid matrix of broth and T. vulgaris EO. This was achieved by employing both Solid Phase MicroExtraction and Gas Tight Syringe sampling techniques. Finally, in our efforts to enhance the antimicrobial activity of T. vulgaris EO vapour, we profiled its composition using a solid matrix composed of cellulose.