Essential Oil of Gallesia Integrifolia is Active Against Mycobacteria

Abstract

Background: There is critical need for new therapeutic options for treatment of diseases caused by mycobacteria. Materials & methods:Gallesia integrifolia essential oils (EOs) and crude extracts (CEs) were tested for their anti-Mycobacterium tuberculosis and anti-nontuberculous mycobacteria activity. Results: Minimum inhibitory concentration (MIC) of EOs ranged from 15.63 to 62.5 μg/ml against M. tuberculosis and 62.5 to >250 μg/ml against nontuberculous mycobacteria. CEs showed low activity. All EO tested demonstrated synergism with antituberculosis drugs. The cytotoxicity of EOs and CEs, in different cell lines, showed selectivity index from 2.2 to 9.8 and >0.056 to 2.0, respectively. Conclusion:G. integrifolia EOs are a candidate for the development of new therapeutic options in the treatment of tuberculosis and other mycobacterial diseases.

Keywords::

• anti-Mycobacterium tuberculosis activity
• checkerboard
• cytotoxicity
• essential oils
• Gallesia integrifolia
• multidrug-resistant
• Mycobacterium tuberculosis
• nontuberculous mycobacteria
• resazurin microtiter plate assay

Author contributions

Conceptualization: D Cássia Montaholi, W de Campos Bortoluci, VL Dias Siqueira, K Rizzieri Caleffi-Ferracioli, R Bertin de Lima Scodro, Z Cristiani Gazim and R Fressatti Cardoso. Formal analysis: D Cássia Montaholi, E Gibin Sampiron and T Leite Valverde. Investigation: D Cássia Montaholi, T Leite Valverde, E Gibin Sampiron and W de Campos Bortoluci. Supervision: R Fressatti Cardoso. Writing, original draft: D Cássia Montaholi; writing, review and editing: W de Campos Bortoluci, V Lucia Dias Siqueira, K Rizzieri Caleffi-Ferracioli, R Bertin de Lima Scodro, Z Cristiani Gazim and R Fressatti Cardoso.

Acknowledgments

The authors are grateful to Laboratório de Bacteriologia Médica, Universidade Estadual de Maringá Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Brazil.

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

Additional information

Funding

The authors are grateful to Laboratório de Bacteriologia Médica, Universidade Estadual de Maringá Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Brazil.