Yuan Yue, Hui Xiuli, Liu Zixuan, Sun Jinlong, Raka Rifat Nowshin, Xiao Junsong, Zhang Zhongwei, Wu Hua
Beijing Technology and Business University, Beijing, 100048, China.
Department of Stomatology, Sixth Medical Center of PLA General Hospital, Beijing, 100048, China.
BMC Complement Med Ther. 2025 Jul 22;25(1):283. doi: 10.1186/s12906-025-05007-5.
Globally, according to WHO estimates, severe periodontitis affects over 1 billion people. Porphyromonas gingivalis (P. gingivalis) is a keystone pathogen in the development of chronic periodontitis. Although two commercial essential oils (EOs) derived from Satureja montana L. (EO1) and Leptospermum scoparium J.R.Forst. & G.Forst. (EO2) have demonstrated promising antibacterial potential, their mechanisms against P. gingivalis and the influence of their distinct metabolite profiles remain unclear.
EO metabolite profiles were analyzed using gas chromatography-mass spectrometry. Antibacterial activity was assessed using the disk diffusion, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and bacterial growth curves. Their effects on hemagglutination, hemolytic, black pigmentation formation, autoaggregation, hydrophobicity, biofilm formation and virulence gene expression were evaluated. Molecular docking simulated interactions between metabolites and the virulence proteins. Cytotoxicity at MIC was tested in RAW264.7 cells using MTT assays.
EO1 showed stronger antibacterial effects than EO2, with inhibition zone diameters (42.06 ± 1.62 versus 40.36 ± 0.47 mm), lower MIC (71.33 versus 305.00 µg/mL), and MBC (142.66 µg/mL versus 1220.00 µg/mL). The bacterial growth curves demonstrated sustained inhibition. EO1 can inhibit P. gingivalis hemagglutination, hemolysis (p < 0.05), and heme accumulation at 1/8 - 1/2 MIC, while EO2 only affected heme accumulation. Both EOs reduced P. gingivalis hydrophobicity levels below 50% at 1/4 to 1/2 MIC and achieved biofilm inhibition rates exceeding 85% at MIC (p < 0.05). The distinct inhibitory mechanisms against the pathogenic processes of P. gingivalis likely stem from their differing metabolite profiles. EO1 was dominated by monoterpenes (56.00 ± 0.55%), and the main metabolites were γ-terpinene (20.20 ± 0.38%), p-cymene (16.01 ± 0.66%), and carvacrol (14.50 ± 0.35%), whereas EO2 contained up to 71.19 ± 0.18% sesquiterpenes, its main metabolites were leptospermone (17.44 ± 0.40%). Molecular docking analysis predicted these metabolites as key active components. Besides, at MIC, cell viability was 86.68% for EO1 and 68.81% for EO2.
The comprehensive analysis reveals that EO1 and EO2 exert multi-mode antibacterial effects through different mechanisms. Notably, EO1 demonstrated greater potential against P. gingivalis, which may be attributed to its unique metabolite composition. These findings offer a theoretical foundation and new insights for advancing the application of EOs in the prevention and adjunctive management of periodontitis.
据世界卫生组织估计，全球范围内，重度牙周炎影响着超过10亿人。牙龈卟啉单胞菌（P. gingivalis）是慢性牙周炎发展过程中的关键病原体。虽然两种源自山地风轮菜（EO1）和新西兰茶树（EO2）的市售精油已显示出有前景的抗菌潜力，但其针对牙龈卟啉单胞菌的作用机制以及它们独特的代谢产物谱的影响仍不清楚。
使用气相色谱 - 质谱法分析精油代谢产物谱。使用纸片扩散法、最低抑菌浓度（MIC）、最低杀菌浓度（MBC）和细菌生长曲线评估抗菌活性。评估它们对血凝、溶血、黑色素形成、自聚集、疏水性、生物膜形成和毒力基因表达的影响。分子对接模拟代谢产物与毒力蛋白之间的相互作用。使用MTT法在RAW264.7细胞中测试MIC时的细胞毒性。
EO1显示出比EO2更强的抗菌作用，抑菌圈直径（42.06±1.62对40.36±0.47毫米）、更低的MIC（71.33对305.00微克/毫升）和MBC（142.66微克/毫升对1220.00微克/毫升）。细菌生长曲线显示出持续抑制。EO1在1/8 - 1/2 MIC时可抑制牙龈卟啉单胞菌的血凝、溶血（p<0.05）和血红素积累，而EO2仅影响血红素积累。两种精油在1/4至1/2 MIC时将牙龈卟啉单胞菌的疏水性水平降低至50%以下，并在MIC时实现超过85%的生物膜抑制率（p<0.05）。针对牙龈卟啉单胞菌致病过程的不同抑制机制可能源于它们不同的代谢产物谱。EO1以单萜类为主（56.00±0.55%），主要代谢产物为γ - 萜品烯（20.20±0.38%）、对伞花烃（16.01±0.66%）和香芹酚（14.50±0.35%），而EO2含有高达71.19±0.18%的倍半萜类，其主要代谢产物为细籽酮（17.44±0.40%）。分子对接分析预测这些代谢产物为关键活性成分。此外，在MIC时，EO1的细胞活力为86.68%，EO2为68.81%。
综合分析表明，EO1和EO2通过不同机制发挥多模式抗菌作用。值得注意的是，EO1对牙龈卟啉单胞菌显示出更大的潜力，这可能归因于其独特的代谢产物组成。这些发现为推进精油在牙周炎预防和辅助治疗中的应用提供了理论基础和新见解。
