Antimycobacterial Activity of Cinnamaldehyde in a Mycobacterium tuberculosis(H37Ra) Model

• Main Authors: Rafal Sawicki, Joanna Golus, Agata Przekora, Agnieszka Ludwiczuk, Elwira Sieniawska, Grazyna Ginalska
• Format: Article
• Language: English
• Published: MDPI AG 2018-09-01
• Series: Molecules
• Subjects: selectivity index; synergy; cell membrane; stress sensing; clgR expression
• Online Access: http://www.mdpi.com/1420-3049/23/9/2381

The purpose of the study was to evaluate the antimycobacterial activity and the possible action mode of cinnamon bark essential oil and its main constituent—cinnamaldehyde—against the Mycobacterium tuberculosis ATCC 25177 strain. Cinnamaldehyde was proved to be the main bioactive compound responsible for mycobacterial growth inhibition and bactericidal effects. The antimycobacterial activity of cinnamaldehyde was found to be comparable with that of ethambutol, one of the first-line anti-TB antibiotics. The selectivity index determined using cell culture studies in vitro showed a high biological potential of cinnamaldehyde. In M. tuberculosis cells exposed to cinnamaldehyde the cell membrane stress sensing and envelope preserving system are activated. Overexpression of clgR gene indicates a threat to the stability of the cell membrane and suggests a possible mechanism of action. No synergism was detected with the basic set of antibiotics used in tuberculosis treatment: ethambutol, isoniazid, streptomycin, rifampicin, and ciprofloxacin.