Anti-Haemophilus Activity of Selected Essential Oils Detected by TLC-Direct Bioautography and Biofilm Inhibition

Molecules

Judit Krisch¹  DávidU. Nagy²  Adorján Varga³  Béla Kocsis³  Erika Kerekes⁴  ViktóriaLilla Balázs⁵  Kamilla Ács⁵  Györgyi Horváth⁵  Aleksandar Széchenyi⁶  Barbara Horváth⁶  Andrea Böszörményi⁷ 

[1] Department of Food Engineering, Faculty of Engineering, University of Szeged, H-6724 Szeged, Hungary;Department of Genetics and Molecular Biology, Institute of Biology, Faculty of Sciences, University of Pécs, H-7624 Pécs, Hungary;Department of Medical Microbiology and Immunology, Medical School, University of Pécs, H-7624 Pécs, Hungary;Department of Microbiology, Faculty of Science and Informatics, University of Szeged, H-6726 Szeged, Hungary;Department of Pharmacognosy, Faculty of Pharmacy, University of Pécs, H-7624 Pécs, Hungary;Institute of Pharmaceutical Technology and Biopharmacy, Faculty of Pharmacy, University of Pécs, H-7624 Pécs, Hungary;Institute of Pharmacognosy, Faculty of Pharmacy, Semmelweis University, H-1085 Budapest, Hungary;

关键词: essential oil;    clove;    thyme;    cinnamon bark;    peppermint;    anti-biofilm activity;    Pickering nano-emulsion;    Haemophilus influenzae;    Haemophilus parainfluenzae;   

DOI  :  10.3390/molecules24183301

来源: DOAJ

【 摘 要 】

Essential oils (EOs) are becoming increasingly popular in medical applications because of their antimicrobial effect. Direct bioautography (DB) combined with thin layer chromatography (TLC) is a screening method for the detection of antimicrobial compounds in plant extracts, for example, in EOs. Due to their lipophilic character, the common microbiological assays (etc. disk diffusion) could not provide reliable results. The aim of this study was the evaluation of antibacterial and anti-biofilm properties of the EO of cinnamon bark, clove, peppermint, thyme, and their main components against Haemophilus influenzae and H. parainfluenzae. Oil in water (O/W) type Pickering nano-emulsions stabilized with silica nanoparticles from each oil were prepared to increase their water-solubility. Samples with Tween80 surfactant and absolute ethanol were also used. Results showed that H. influenzae was more sensitive to the EOs than H. parainfluenzae (except for cinnamon bark oil). In thin layer chromatography-direct bioautography (TLC-DB) the ethanolic solutions of thyme oil presented the best activity against H. influenzae, while cinnamon oil was the most active against H. parainfluenzae. Pickering nano-emulsion of cinnamon oil inhibited the biofilm formation of H. parainfluenzae (76.35%) more efficiently than samples with Tween80 surfactant or absolute ethanol. In conclusion, Pickering nano-emulsion of EOs could inhibit the biofilm production effectively.

【 授权许可】

Unknown