Antioxidant Activity and Chemical Composition of Geranium Oil and Its Synergistic Potential against Pneumococci with Various Antibiotic Combinations

The essential oil of Pelargonium graveolens L. is valuable for its therapeutic benefits, so this study aimed to determine the synergistic effect of the combination of the essential oil of this plant with antibiotics instead of the extracts prepared with various solvents. In addition, the second goal of this study was to determine whether the essential oil combined with various antibiotics increased the overall killing activity in mouse macrophage cells with the aim of introducing an immunotherapeutic approach to the infection treatments used today. Herein, the volatile profile of Geranium oil (G.O) was analyzed using GC/MS. The current study sought to assess the synergistic characteristics of several antibiotic combinations using G.O against pneumococci, as well as the oil's antioxidant and antimicrobial activities. The major components of the oil were citronellol, geraniol, and isomenthone. In the combinations of G.O and antibiotics, the synergism of the Streptococcus pneumoniae to antibiotics advanced. When the time-kill data were evaluated, G.O + antibiotic combinations quickly diminished the viable cell count of S. pneumoniae from the 6th h. In this study, the combined use of existing antibiotics used in infection treatments with G.O could improve antibiotic effectiveness and thus prevent bacteria from developing antibiotic resistance.

Automated summary

This study aimed to determine the synergistic effect of the combination of Pelargonium graveolens L. essential oil with antibiotics and its potential immunotherapeutic approach to infection treatments. The major components of the oil were identified as citronellol, geraniol, and isomenthone. The combination of essential oil and antibiotics showed enhanced effectiveness against Streptococcus pneumoniae, making it a potential solution to prevent antibiotic resistance. Overall, this research is of great importance in exploring new treatment options and improving antibiotic effectiveness.