Department of Applied Chemistry, College of Art and Science, Northeast Agricultural University, Harbin 150030, China.
Department of Veterinary Pharmacy, College of Veterinary Medicine, Northeast Agricultural University, Harbin 150030, China.
Molecules. 2021 Feb 27;26(5):1295. doi: 10.3390/molecules26051295.
Syringopicroside is a natural drug with antibacterial activity, which is the main ingredient of Lindl (). In order to further develop the application of and evaluate the ability of syringopicroside against (), this investigation first applied an ultrasonic-assisted method to extract syringopicroside, and then response surface methodology (RSM) was performed to get the optimum condition. Based on RSM analysis, a second-order polynomial equation about the syringopicroside yield and four variables, including ultrasonic power, time, temperature, and liquid-to-solid ratio, was purposed. Through RSM prediction and model verification experiments, the optimum conditions were determined, as follows: ultrasonic time was 63 min, temperature was 60 °C, a liquid-to-solid ratio was set to 63 mL/g, and ultrasonic power was 835 W. Under this condition, a high syringopicroside yield was obtained (3.07 ± 0.13 mg/g), which was not significantly different with a predicated value. After separation and purification by HPD 500 microporous resin, then mass spectrum was applied to identify the main ingredient in aqueous extract. A minimal inhibitory concentration (MIC) assay revealed the value against of syringopicroside was 2.56 µg/µL and syringopicroside with sub-inhibitory concentrations that could effectively inhibit biofilm formation of . Besides, scanning electron microscopy analysis indicated syringopicroside could destroy the multi-layered aggregation structure of . Finally, molecular docking analysis confirmed that syringopicroside was combined with Orfy protein of through hydrogen bonds, hydrophobic interaction, and π-π stacking.
丁香苷是一种具有抗菌活性的天然药物，是 Lindl（）的主要成分。为了进一步开发 的应用并评估丁香苷对 （）的抑制能力，本研究首先采用超声辅助法提取丁香苷，然后应用响应面法（RSM）得到最佳条件。基于 RSM 分析，提出了一个关于丁香苷产率和四个变量（包括超声功率、时间、温度和液固比）的二次多项式方程。通过 RSM 预测和模型验证实验，确定了最佳条件，如下：超声时间为 63 分钟，温度为 60°C，液固比为 63 mL/g，超声功率为 835 W。在该条件下，可获得较高的丁香苷产率（3.07±0.13mg/g），与预测值无显著差异。经 HPD 500 大孔树脂分离纯化后，采用质谱法鉴定水提物中的主要成分。微量稀释法抑菌试验结果表明，丁香苷对 的最小抑菌浓度（MIC）值为 2.56µg/µL，亚抑菌浓度可有效抑制 的生物膜形成。扫描电子显微镜分析表明，丁香苷可破坏 的多层聚集结构。最后，分子对接分析证实丁香苷通过氢键、疏水相互作用和 π-π 堆积与 中的 Orfy 蛋白结合。
