本研究旨在揭示辣木叶乙醇提取物（Moringa oleifera leaf ethanolic extract，MOLEE）的抑菌抗炎活性，从而为MOLEE在护肤化妆品中的应用提供理论依据。使用不同质量浓度的MOLEE处理金黄色葡萄球菌和大肠杆菌24 h，分别检测MOLEE对两种菌株的最小抑菌浓度（MIC）和抑菌圈直径。使用CCK-8试剂盒检测了不同质量浓度的MOLEE对RAW264.7细胞活力的影响。之后，将RAW264.7细胞分为对照组（C）、脂多糖（LPS）组和LPS+1，10，50，100，200，300，400，500 μg/mL MOLEE组，然后用1 μg/mL LPS和不同质量浓度的MOLEE处理细胞24 h。使用RT-qPCR检测RAW264.7细胞中的环氧合酶-2（COX-2）、诱导型一氧化氮合酶（iNOS）、肿瘤坏死因子-α（TNF-α）、白介素（IL）-1β和IL-6的转录水平。采用Western blotting检测核因子-κB（NF-κB）的磷酸化水平。结果显示，MOLEE对金黄色葡萄球菌和大肠杆菌的MIC分别为300和400 μg/mL。与0 μg/mL MOLEE组相比，50，100，200，300，400，500 μg/mL MOLEE组的两种菌株的抑菌圈直径均呈MOLEE剂量依赖性升高（P<0.001）。在1~500 μg/mL的MOLEE质量浓度范围内，MOLEE对RAW264.7细胞活力无影响（P>0.05）。与LPS组相比，LPS+50，100，200，300，400，500 μg/mL MOLEE组RAW264.7细胞中NO和PGE2含量降低，COX-2、iNOS、TNF-α、IL-1β和IL-6 mRNA相对水平降低，NF-κB p65相对磷酸化水平降低，且均具有MOLEE剂量依赖性（P<0.05）。本研究表明MOLEE具有良好的抑菌抗炎活性。
This study aims to reveal the antibacterial and anti-inflammatory activity of Moringa oleifera leaf ethanolic extract （MOLEE）, thereby providing a theoretical basis for the application of MOLEE in skin care cosmetics. Staphylococcus aureus and Escherichia coli were treated with different mass concentrations of MOLEE （0, 1, 10, 50, 100, 200, 300, 400, 500 μg/mL） for 24 h. The minimal inhibitory concentration （MIC） and the antimicrobial zone diameter of MOLEE to the two strains were detected respectively. The effects of different mass concentrations of MOLEE on the viability of RAW264.7 cells were detected by CCK-8 kit. After that, RAW264.7 cells were divided into control group （C）, LPS group and LPS+1, 10, 50, 100, 200, 300, 400, 500 μg/mL MOLEE group, and then treated with 1 μg/mL LPS and different mass concentrations of MOLEE for 24 h. The transcriptional levels of cyclooxygenase-2（COX-2）, inducible nitric oxide synthase （iNOS）, tumor necrosis factor-α （TNF-α）, interleukin （IL）-1β and IL-6 in RAW264.7 cells were detected by RT-qPCR. The phosphorylation level of Nuclear factor-κB （NF-κB） was detected by Western blotting. The results show that the MIC of MOLEE against Staphylococcus aureus and Escherichia coli are 300 and 400 μg/mL, respectively. Compared with 0 μg/mL group, the antimicrobial zone diameter of the two strains in 50, 100, 200, 300, 400, 500 μg/mL groups increase in a dose-dependent manner （P<0.001）. In the concentration range of 1-500 μg/mL, MOLEE has no effect on the viability of RAW264.7 cells （P>0.05）. Compared with LPS group, the contents of NO and PGE2, the relative levels of COX-2, iNOS, TNF-α, IL-1β and IL-6 mRNA, and the relative phosphorylation level of NF-κB p65 in RAW264.7 cells in LPS+50, 100, 200, 300, 400, 500 μg/mL MOLEE groups decrease in a dose-dependent manner （P<0.05）. This study shows that MOLEE has good antibacterial and anti-inflammatory activity, suggesting that MOLEE may be a cosmetic additive material.
