Sdu-Anu Joint Science College, Shandong University, Weihai 264209, China.
Marine College, Shandong University, Weihai 264209, China.
Molecules. 2022 Jul 20;27(14):4631. doi: 10.3390/molecules27144631.
In response to the need for novel therapeutic strategies to combat the development of microbial resistance, plant essential oils may represent a promising alternative source. This study set out to characterize the chemical composition and assess the antibacterial potential of Less. essential oil (MNEO). Essential oil isolated from by hydrodistillation was analyzed using a GC-MS technique. The antibacterial properties of MNEO alone and combined with antibiotics (chloramphenicol and streptomycin) were tested via the disc diffusion, microbroth dilution, and checkerboard methods. MNEO was represented by oxygenated sesquiterpenes (60.3%) and sesquiterpene hydrocarbons (28.6%), with caryophyllene oxide, spathulenol, humulene epoxide II, β-elemene, neointermedeol, and β-caryophyllene as the main compounds. MNEO exhibited a strong antibacterial effect against Gram-positive bacteria, with MIC and MBC values of 0.039 mg/mL and 0.039-0.156 mg/mL, respectively, and synergistic effects were observed in both combinations with chloramphenicol and streptomycin. Furthermore, the antibiofilm and cytotoxic activities of MNEO were also evaluated. The crystal violet assay was used for quantification of biofilm formation, and an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay was conducted to determine cell viability. The results revealed MNEO could dose-dependently inhibit biofilm formation and possessed potential cytotoxic on both normal and cancer cells (IC values from 13.13 ± 1.90 to 35.22 ± 8.36 μg/mL). Overall, the results indicate that MNEO may have promising applications in the field of bacterial infections.
为了应对新型治疗策略的需求，以对抗微生物耐药性的发展，植物精油可能是一种有前途的替代来源。本研究旨在对来自 Less. 的精油（MNEO）的化学成分进行特征描述，并评估其抗菌潜力。通过 GC-MS 技术对用水蒸气蒸馏法从 中分离出的精油进行分析。单独使用 MNEO 以及与抗生素（氯霉素和链霉素）联合使用的抗菌特性通过圆盘扩散、微量肉汤稀释和棋盘微量稀释法进行测试。MNEO 主要由含氧倍半萜（60.3%）和倍半萜烃（28.6%）组成，其主要化合物为石竹烯氧化物、spathulenol、葎草烯氧化物 II、β-榄香烯、neointermedeol 和 β-石竹烯。MNEO 对革兰氏阳性菌表现出很强的抗菌作用，MIC 和 MBC 值分别为 0.039 mg/mL 和 0.039-0.156 mg/mL，与氯霉素和链霉素联合使用时均表现出协同作用。此外，还评估了 MNEO 的抗生物膜和细胞毒性活性。结晶紫法用于定量测定生物膜形成，MTT（3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐）法用于测定细胞活力。结果表明，MNEO 可以剂量依赖性地抑制 生物膜的形成，并且对正常细胞和癌细胞都具有潜在的细胞毒性（IC 值从 13.13 ± 1.90 至 35.22 ± 8.36 μg/mL）。总的来说，这些结果表明 MNEO 可能在细菌感染领域具有应用前景。
