Investigation of Antibacterial Properties of St. John's wort oil (Hypericum perforatum L.) and Maryam's plant (Geum urbanum L.)
Abstract
This study aimed to evaluate the in vitro antibacterial activity of St. John’s wort (Hypericum perforatum L.) oil and Geum urbanum L. extracts against standard bacterial strains. Plant materials were collected from mountainous areas of the Karamürsel district in Kocaeli province, Türkiye. St. John’s wort oil was prepared by macerating the plant material in olive oil under dark conditions for six months. Geum urbanum extracts were obtained using different organic solvents, including ethanol, methanol, and chloroform, to assess the effect of solvent type on extraction performance and antibacterial activity. Antibacterial activity was evaluated using the disk diffusion method against Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 15442, and Klebsiella aerogenes ATCC 13048. St. John’s wort oil alone exhibited inhibitory activity against S. aureus (10 ± 0.5 mm) and P. aeruginosa (8 ± 0.6 mm), while no inhibition was observed against K. aerogenes. In contrast, combinations of H. perforatum oil with G. urbanum extracts demonstrated enhanced antibacterial activity against all tested strains. The most pronounced effects were observed with ethanol and methanol extracts. The ethanol combination produced inhibition zones of 15 ± 0.7 mm (S. aureus), 15 ± 0.5 mm (P. aeruginosa), and 13 ± 0.6 mm (K. aerogenes), while methanol extracts yielded 16 ± 0.6 mm, 15 ± 0.4 mm, and 10 ± 0.5 mm, respectively. Chloroform extracts showed comparatively lower antibacterial activity. Standard antibiotics produced higher inhibition zones compared to plant-derived samples, confirming the validity of the assay. Overall, these findings indicate that Hypericum perforatum L. oil and Geum urbanum L. extracts, particularly when obtained using appropriate solvents and applied in combination, possess considerable antibacterial potential and may represent promising natural agents against clinically relevant pathogenic bacteria.
Keywords
Antibacterial effect, Disk diffusion test, St. John's wort, Hypericum perforatum L., St. Maryam's plant, Geum urbanum L.
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Ethical Statement
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References
- Burunkaya, B., Selli, S., & Kelebek, H. (2021). Sarı kantaron (Hypericum perforatum L.) fenoliklerinin karakterizasyonu, antioksidan ve antimikrobiyal potansiyelinin belirlenmesi. Çukurova Journal of Agriculture and Food Science, 36(2), 309–324. https://doi.org/10.36846/CJAFS.2021.58
- Karcı, H. (2025). Sarı kantaron (Hypericum perforatum) bitkisinin antikanser ve antimikrobiyal özellikleri. İnönü Üniversitesi Sağlık Hizmetleri Meslek Yüksekokulu Dergisi, 13(1), 180–190. https://doi.org/10.33715/inonusaglik.1544916
- Tian, J., Zhang, F., Cheng, J., Guo, S., Liu, P., & Wang, H. (2014). Antidepressant-like activity of adhyperforin, a novel constituent of Hypericum perforatum L. Scientific Reports, 4(1), 1–6. https://doi.org/10.1038/srep05915
- Oliveira, A. I., Pinho, C., Sarmento, B., & Dias, A. C. P. (2016). Neuroprotective activity of Hypericum perforatum and its major components. Frontiers in Plant Science, 7, 1004. https://doi.org/10.3389/fpls.2016.01004
- Kisa, O., Oksuz, L., Servi, H., & Aysal, A. I. (2025). Antibacterial activity of Hypericum perforatum L. (St. John's wort) extracts against Gram-positive bacteria and characterisation of its secondary metabolites. Natural Product Research, 39(5), 1019–1026. https://doi.org/10.1080/14786419.2023.2291702
- Ertürk, Ö., Aydın, G., & Ayvaz, M. Ç. (2020). Hypericum perforatum L. esansiyel yağının in vitro antimikrobiyal, antioksidan aktivite ve kimyasal karakterizasyonu. Artvin Çoruh Üniversitesi Orman Fakültesi Dergisi, 21(2), 330–339.
- Yıldırım, N., & Küçük, İ. (2020). Sarı kantaron (Hypericum perforatum) katkılı kitosan ve jelatin esaslı yara örtücü filmlerinin üretimi ve karakterizasyonu. Journal of the Faculty of Engineering and Architecture of Gazi University, 35(1), 127–135.
- Farasati Far, B., Gouranmohit, G., Naimi-Jamal, M. R., Neysani, E., El-Nashar, H. A. S., El-Shazly, M., & Khoshnevisan, K. (2024). The potential role of Hypericum perforatum in wound healing: A literature review on the phytochemicals, pharmacological approaches, and mechanistic perspectives. Phytotherapy Research, 38(7), 3271–3295. https://doi.org/10.1002/ptr.8204
- Yılmazoğlu, E., Metin Hasdemir, İ., Hasdemir, B., & Yaşa, H. (2023). Investigation of essential oil composition, hypericin content, and antioxidant capacity of different extracts from flowers and leaves of Hypericum perforatum L. growing wild in Turkey. Journal of Essential Oil Bearing Plants, 26(6), 1350–1370. https://doi.org/10.1080/0972060X.2023.2292544
- Dimitrova, L., Mileva, M., Georgieva, A., Tzvetanova, E., Popova, M., Bankova, V., & Najdenski, H. (2025a). Redox-modulating capacity and effect of ethyl acetate roots and aerial parts extracts from Geum urbanum L. on the phenotype inhibition of the Pseudomonas aeruginosa Las/Rhl quorum sensing system. Plants, 14(2), 213. https://doi.org/10.3390/plants14020213