Selenium nanoparticles (Se-NPs) have different applications in various technologies due to their individual properties. In order to investigate the impacts of different concentrations of a green-synthesized selenium nano-complex (0, 20, 40, 60, and 80 mg L⁻¹) on the chemical composition, antioxidant capacity and antimicrobial activity of lemongrass essential oil (EO), an experiment was designed as a completely randomized design (CRD) with four replications. The application of 40 mg L⁻¹ selenium nano-complex caused the highest EO yield (3.96 ± 0.09%). The dominant compounds in EO, geranial (44.12 ± 1.22%) and neral (32.53 ± 1.08%), were achieved by the application of 60 mg L⁻¹ selenium nano-complex. HPLC analysis indicated that the extracts were rich in 5-o-cafeoylquinicacid, luteolin 6-c-pentosyl-8-c-pentoside, and luteolin 2-o-deoxyhexosyl-6-c-glucoside. The extracts of lemongrass plants treated with 40 and 60 mg L⁻¹ selenium nano-complex achieved the highest amount of 5-o-cafeoylquinicacid (25.29±1.31 and 24.16±1.26 µg mL⁻¹, respectively). The highest antioxidant capacity was observed in the 40 mg L⁻¹ selenium nano-complex treated plants. The minimum inhibitory concentration (MIC) of EO derived from the 60 mg L⁻¹ selenium nano-complex treated lemongrass for Salmonella typhimurium, Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Aspergillus niger and Candida albicans was 0.63±0.03, 1.84±0.1, 1.05±0.05, 0.008±0.01, 0.6±0.01 and 0.1±0.01 mg mL⁻¹, respectively. It is expected that the selenium nano-complex would find a wide range of applications in medicine for its antioxidant and antimicrobial properties. It may also be applied to medicinal plants to enhance the quality and quantity of EOs.

硒纳米粒子（Se-NPs）由于其各自的特性而在各种技术中具有不同的应用。为了研究不同浓度的绿色合成硒纳米复合物（0、20、40、60 和 80 mg L ^-1）对柠檬草精油（EO）的化学成分、抗氧化能力和抗菌活性的影响。 )，实验被设计为具有四次重复的完全随机设计 (CRD)。应用 40 mg L ^-1硒纳米复合物导致最高的 EO 产率（3.96 ± 0.09%）。EO 中的主要化合物 Geranial (44.12 ± 1.22%) 和neral (32.53 ± 1.08%) 是通过施用 60 mg L ^-1实现的硒纳米复合物。HPLC分析表明，提取物富含5-o-咖啡酰奎尼酸、木犀草素6-c-戊糖基-8-c-戊糖苷和木犀草素2-o-脱氧己糖基-6-c-葡萄糖苷。用 40 和 60 mg L ^-1硒纳米复合物处理的柠檬草植物提取物达到了最高量的 5-邻咖啡酰奎尼酸（分别为 25.29±1.31 和 24.16±1.26 μg mL ^-1）。^{在 40 mg L -1}硒纳米复合物处理的植物中观察到最高的抗氧化能力。来自 60 mg L ^-1硒纳米复合物处理的柠檬草的 EO 对鼠伤寒沙门氏菌、大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌、黑曲霉和白色念珠菌分别为0.63±0.03、1.84±0.1、1.05±0.05、0.008±0.01、0.6±0.01和0.1±0.01 mg mL ^-1。预计硒纳米复合物将因其抗氧化和抗菌特性而在医学中得到广泛的应用。它也可应用于药用植物以提高 EO 的质量和数量。