Evaluation of in vitro growth-inhibitory effect of organic volatile compounds against pneumonia causing bacteria in vapor phase

Agáta Moulíková

Bakalářská práce

Abstract:

Pneumonia represents a significant global health burden, with its treatment becoming increasingly challenging due to the growing emergence of antibiotic-resistant bacteria. In response to this trend, alternative therapeutic approaches are being investigated, particularly the antimicrobial potential of volatile organic compounds derived from plants and other biological sources. The objective of this thesis was to determine the growth-inhibitory effects of selected organic compounds, namely citral, 2,5-dihydroxy-1,4-benzoquinone, 2,5-dimethyl-1,4-benzoquinone, and 8-hydroxyquinolinol against Haemophilus influenzae, Staphylococcus aureus, and Streptococcus pneumoniae, which are among the bacterial pathogens responsible for pneumonia. Using the broth microdilution volatilisation method, the antibacterial activity was assessed in both liquid and vapor phases. The results indicated that 2,5-dimethyl-1,4-benzoquinone and 8-hydroxyquinolinol were the most effective agents in the vapor phase, inhibiting bacterial growth at relatively low concentrations. Notably, 8-hydroxyquinolinol demonstrated a minimum inhibitory concentration (MIC) of 8 μg/mL against H. influenzae and S. aureus, whereas 2,5-dimethyl-1,4-benzoquinone exhibited MICs of 32 μg/mL and 64 μg/mL, respectively. Against S. pneumoniae, both substances exhibited MIC values of 128 μg/mL. These findings suggest that such compounds may have potential in the development of inhalation-based strategies for pneumonia treatment, although further research is needed to confirm their efficacy and evaluate their safety.

Keywords

organic volatile compounds, broth microdilution volatilization method, antibacterial activity, vapour phase

Jazyk práce: angličtina

Datum vytvoření / odevzdání či podání práce: 19. 4. 2026

Obhajoba závěrečné práce

• Obhajoba proběhla 27. 5. 2026
• Vedoucí: prof. Ing. Ladislav Kokoška, Ph.D.
• Oponent: Tomáš Kudera, Ph.D.

Česká zemědělská univerzita v Praze

Fakulta tropického zemědělství

Bakalářský studijní program:
Tropické zemědělství