P084
Antimycobacterial activity of Bulgarian essential oils from Rosa species against reference and clinical Mycobacterium tuberculosis strains
V Valcheva(1) M Mileva(1) M Dogonadze(2) A Dobreva(3) I Mokrousov(4,5)
1:Stephan Angeloff Institute of microbiology, Bulgarian Academy of Sciences; 2:St. Petersburg Research Institute of Phthisiopulmonology, St. Petersburg, Russia; 3:Institute for Roses and Aromatic Plants, Agricultural Academy, Kazanlak, Bulgaria; 4:St. Petersburg Pasteur Institute, St. Petersburg,Russia; 5:Children's Hospital Affiliated to Zhengzhou University, Zhengzhou, China
Based on the valuable biological properties of rose essential oils, the aim of this study was to evaluate the antimycobacterial activity of four Bulgarian oil-bearing roses: Rosa damascena Mill., R. alba L., R. centifolia L., and R. gallica L.. against M. tuberculosis H37Rv and clinical Beijing and LAM genotype. The chemical composition of the essential oils was determined by Gas chromatography (GC-FID/MS). Minimal inhibitory concentrations (MIC) were determined using the REMA method. R. alba oil showed the highest inhibitory activity against all M. tuberculosis strains with MIC in the range of 0.16-0.31 mg/ml, while R. gallica oil was the least active (MIC 0.62-1.25 mg/ml). The obtained results show heterogeneity of rose oil action on different mycobacterial strains. Strain Beijing 396 was relatively more susceptible to the rose oils probably due to multiple and likely deleterious mutations in its efflux pump genes. This study allows us to hypothesize that the combined level of geraniol and nerol is a key factor that underlies the antimycobacterial action of the Rose oils. Further investigations are needed to show a possible synergistic action of the new-generation anti-TB drugs and the most promising rose oil extract on the large panel of different strains. This study was supported by the Bulgarian National Science Fund (Grant KP-06-H41/3, 2020 and KP-06-H36/17, 2019).